diff options
| author | Ian Lewis <ianmlewis@gmail.com> | 2020-08-17 21:44:31 -0400 |
|---|---|---|
| committer | Ian Lewis <ianmlewis@gmail.com> | 2020-08-17 21:44:31 -0400 |
| commit | ac324f646ee3cb7955b0b45a7453aeb9671cbdf1 (patch) | |
| tree | 0cbc5018e8807421d701d190dc20525726c7ca76 /pkg/sentry/syscalls/linux | |
| parent | 352ae1022ce19de28fc72e034cc469872ad79d06 (diff) | |
| parent | 6d0c5803d557d453f15ac6f683697eeb46dab680 (diff) | |
Merge branch 'master' into ip-forwarding
- Merges aleksej-paschenko's with HEAD
- Adds vfs2 support for ip_forward
Diffstat (limited to 'pkg/sentry/syscalls/linux')
78 files changed, 9391 insertions, 1294 deletions
diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD index 4c0bf96e4..4a9b04fd0 100644 --- a/pkg/sentry/syscalls/linux/BUILD +++ b/pkg/sentry/syscalls/linux/BUILD @@ -1,4 +1,4 @@ -load("//tools/go_stateify:defs.bzl", "go_library") +load("//tools:defs.bzl", "go_library") package(licenses = ["notice"]) @@ -8,11 +8,11 @@ go_library( "error.go", "flags.go", "linux64.go", - "linux64_amd64.go", - "linux64_arm64.go", "sigset.go", "sys_aio.go", "sys_capability.go", + "sys_clone_amd64.go", + "sys_clone_arm64.go", "sys_epoll.go", "sys_eventfd.go", "sys_file.go", @@ -30,6 +30,7 @@ go_library( "sys_random.go", "sys_read.go", "sys_rlimit.go", + "sys_rseq.go", "sys_rusage.go", "sys_sched.go", "sys_seccomp.go", @@ -39,6 +40,8 @@ go_library( "sys_socket.go", "sys_splice.go", "sys_stat.go", + "sys_stat_amd64.go", + "sys_stat_arm64.go", "sys_sync.go", "sys_sysinfo.go", "sys_syslog.go", @@ -46,28 +49,31 @@ go_library( "sys_time.go", "sys_timer.go", "sys_timerfd.go", - "sys_tls.go", + "sys_tls_amd64.go", + "sys_tls_arm64.go", "sys_utsname.go", "sys_write.go", + "sys_xattr.go", "timespec.go", ], - importpath = "gvisor.dev/gvisor/pkg/sentry/syscalls/linux", visibility = ["//:sandbox"], deps = [ "//pkg/abi", "//pkg/abi/linux", "//pkg/binary", "//pkg/bpf", + "//pkg/context", "//pkg/log", "//pkg/metric", "//pkg/rand", + "//pkg/safemem", "//pkg/sentry/arch", - "//pkg/sentry/context", "//pkg/sentry/fs", "//pkg/sentry/fs/anon", "//pkg/sentry/fs/lock", "//pkg/sentry/fs/timerfd", "//pkg/sentry/fs/tmpfs", + "//pkg/sentry/fsbridge", "//pkg/sentry/kernel", "//pkg/sentry/kernel/auth", "//pkg/sentry/kernel/epoll", @@ -82,15 +88,18 @@ go_library( "//pkg/sentry/loader", "//pkg/sentry/memmap", "//pkg/sentry/mm", - "//pkg/sentry/safemem", "//pkg/sentry/socket", "//pkg/sentry/socket/control", "//pkg/sentry/socket/unix/transport", "//pkg/sentry/syscalls", "//pkg/sentry/usage", - "//pkg/sentry/usermem", + "//pkg/sentry/vfs", + "//pkg/sync", "//pkg/syserr", "//pkg/syserror", + "//pkg/usermem", "//pkg/waiter", + "//tools/go_marshal/marshal", + "//tools/go_marshal/primitive", ], ) diff --git a/pkg/sentry/syscalls/linux/error.go b/pkg/sentry/syscalls/linux/error.go index 1d9018c96..46060f6f5 100644 --- a/pkg/sentry/syscalls/linux/error.go +++ b/pkg/sentry/syscalls/linux/error.go @@ -16,13 +16,14 @@ package linux import ( "io" - "sync" "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/log" "gvisor.dev/gvisor/pkg/metric" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) @@ -31,20 +32,58 @@ var ( partialResultOnce sync.Once ) +// HandleIOErrorVFS2 handles special error cases for partial results. For some +// errors, we may consume the error and return only the partial read/write. +// +// op and f are used only for panics. +func HandleIOErrorVFS2(t *kernel.Task, partialResult bool, ioerr, intr error, op string, f *vfs.FileDescription) error { + known, err := handleIOErrorImpl(t, partialResult, ioerr, intr, op) + if err != nil { + return err + } + if !known { + // An unknown error is encountered with a partial read/write. + fs := f.Mount().Filesystem().VirtualFilesystem() + root := vfs.RootFromContext(t) + name, _ := fs.PathnameWithDeleted(t, root, f.VirtualDentry()) + log.Traceback("Invalid request partialResult %v and err (type %T) %v for %s operation on %q", partialResult, ioerr, ioerr, op, name) + partialResultOnce.Do(partialResultMetric.Increment) + } + return nil +} + // handleIOError handles special error cases for partial results. For some // errors, we may consume the error and return only the partial read/write. // // op and f are used only for panics. -func handleIOError(t *kernel.Task, partialResult bool, err, intr error, op string, f *fs.File) error { +func handleIOError(t *kernel.Task, partialResult bool, ioerr, intr error, op string, f *fs.File) error { + known, err := handleIOErrorImpl(t, partialResult, ioerr, intr, op) + if err != nil { + return err + } + if !known { + // An unknown error is encountered with a partial read/write. + name, _ := f.Dirent.FullName(nil /* ignore chroot */) + log.Traceback("Invalid request partialResult %v and err (type %T) %v for %s operation on %q, %T", partialResult, ioerr, ioerr, op, name, f.FileOperations) + partialResultOnce.Do(partialResultMetric.Increment) + } + return nil +} + +// handleIOError handles special error cases for partial results. For some +// errors, we may consume the error and return only the partial read/write. +// +// Returns false if error is unknown. +func handleIOErrorImpl(t *kernel.Task, partialResult bool, err, intr error, op string) (bool, error) { switch err { case nil: // Typical successful syscall. - return nil + return true, nil case io.EOF: // EOF is always consumed. If this is a partial read/write // (result != 0), the application will see that, otherwise // they will see 0. - return nil + return true, nil case syserror.ErrExceedsFileSizeLimit: // Ignore partialResult because this error only applies to // normal files, and for those files we cannot accumulate @@ -53,20 +92,20 @@ func handleIOError(t *kernel.Task, partialResult bool, err, intr error, op strin // Do not consume the error and return it as EFBIG. // Simultaneously send a SIGXFSZ per setrlimit(2). t.SendSignal(kernel.SignalInfoNoInfo(linux.SIGXFSZ, t, t)) - return syserror.EFBIG + return true, syserror.EFBIG case syserror.ErrInterrupted: // The syscall was interrupted. Return nil if it completed // partially, otherwise return the error code that the syscall // needs (to indicate to the kernel what it should do). if partialResult { - return nil + return true, nil } - return intr + return true, intr } if !partialResult { // Typical syscall error. - return err + return true, err } switch err { @@ -75,14 +114,14 @@ func handleIOError(t *kernel.Task, partialResult bool, err, intr error, op strin // read/write. Like ErrWouldBlock, since we have a // partial read/write, we consume the error and return // the partial result. - return nil + return true, nil case syserror.EFAULT: // EFAULT is only shown the user if nothing was // read/written. If we read something (this case), they see // a partial read/write. They will then presumably try again // with an incremented buffer, which will EFAULT with // result == 0. - return nil + return true, nil case syserror.EPIPE: // Writes to a pipe or socket will return EPIPE if the other // side is gone. The partial write is returned. EPIPE will be @@ -90,32 +129,29 @@ func handleIOError(t *kernel.Task, partialResult bool, err, intr error, op strin // // TODO(gvisor.dev/issue/161): In some cases SIGPIPE should // also be sent to the application. - return nil + return true, nil case syserror.ENOSPC: // Similar to EPIPE. Return what we wrote this time, and let // ENOSPC be returned on the next call. - return nil + return true, nil case syserror.ECONNRESET: // For TCP sendfile connections, we may have a reset. But we // should just return n as the result. - return nil + return true, nil case syserror.ErrWouldBlock: // Syscall would block, but completed a partial read/write. // This case should only be returned by IssueIO for nonblocking // files. Since we have a partial read/write, we consume // ErrWouldBlock, returning the partial result. - return nil + return true, nil } switch err.(type) { case kernel.SyscallRestartErrno: // Identical to the EINTR case. - return nil + return true, nil } - // An unknown error is encountered with a partial read/write. - name, _ := f.Dirent.FullName(nil /* ignore chroot */) - log.Traceback("Invalid request partialResult %v and err (type %T) %v for %s operation on %q, %T", partialResult, err, err, op, name, f.FileOperations) - partialResultOnce.Do(partialResultMetric.Increment) - return nil + // Error is unknown and cannot be properly handled. + return false, nil } diff --git a/pkg/sentry/syscalls/linux/flags.go b/pkg/sentry/syscalls/linux/flags.go index 444f2b004..07961dad9 100644 --- a/pkg/sentry/syscalls/linux/flags.go +++ b/pkg/sentry/syscalls/linux/flags.go @@ -50,5 +50,6 @@ func linuxToFlags(mask uint) fs.FileFlags { Directory: mask&linux.O_DIRECTORY != 0, Async: mask&linux.O_ASYNC != 0, LargeFile: mask&linux.O_LARGEFILE != 0, + Truncate: mask&linux.O_TRUNC != 0, } } diff --git a/pkg/sentry/syscalls/linux/linux64.go b/pkg/sentry/syscalls/linux/linux64.go index 68589a377..80c65164a 100644 --- a/pkg/sentry/syscalls/linux/linux64.go +++ b/pkg/sentry/syscalls/linux/linux64.go @@ -15,6 +15,16 @@ // Package linux provides syscall tables for amd64 Linux. package linux +import ( + "gvisor.dev/gvisor/pkg/abi" + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/syscalls" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + const ( // LinuxSysname is the OS name advertised by gVisor. LinuxSysname = "Linux" @@ -25,3 +35,702 @@ const ( // LinuxVersion is the version info advertised by gVisor. LinuxVersion = "#1 SMP Sun Jan 10 15:06:54 PST 2016" ) + +// AMD64 is a table of Linux amd64 syscall API with the corresponding syscall +// numbers from Linux 4.4. +var AMD64 = &kernel.SyscallTable{ + OS: abi.Linux, + Arch: arch.AMD64, + Version: kernel.Version{ + // Version 4.4 is chosen as a stable, longterm version of Linux, which + // guides the interface provided by this syscall table. The build + // version is that for a clean build with default kernel config, at 5 + // minutes after v4.4 was tagged. + Sysname: LinuxSysname, + Release: LinuxRelease, + Version: LinuxVersion, + }, + AuditNumber: linux.AUDIT_ARCH_X86_64, + Table: map[uintptr]kernel.Syscall{ + 0: syscalls.Supported("read", Read), + 1: syscalls.Supported("write", Write), + 2: syscalls.PartiallySupported("open", Open, "Options O_DIRECT, O_NOATIME, O_PATH, O_TMPFILE, O_SYNC are not supported.", nil), + 3: syscalls.Supported("close", Close), + 4: syscalls.Supported("stat", Stat), + 5: syscalls.Supported("fstat", Fstat), + 6: syscalls.Supported("lstat", Lstat), + 7: syscalls.Supported("poll", Poll), + 8: syscalls.Supported("lseek", Lseek), + 9: syscalls.PartiallySupported("mmap", Mmap, "Generally supported with exceptions. Options MAP_FIXED_NOREPLACE, MAP_SHARED_VALIDATE, MAP_SYNC MAP_GROWSDOWN, MAP_HUGETLB are not supported.", nil), + 10: syscalls.Supported("mprotect", Mprotect), + 11: syscalls.Supported("munmap", Munmap), + 12: syscalls.Supported("brk", Brk), + 13: syscalls.Supported("rt_sigaction", RtSigaction), + 14: syscalls.Supported("rt_sigprocmask", RtSigprocmask), + 15: syscalls.Supported("rt_sigreturn", RtSigreturn), + 16: syscalls.PartiallySupported("ioctl", Ioctl, "Only a few ioctls are implemented for backing devices and file systems.", nil), + 17: syscalls.Supported("pread64", Pread64), + 18: syscalls.Supported("pwrite64", Pwrite64), + 19: syscalls.Supported("readv", Readv), + 20: syscalls.Supported("writev", Writev), + 21: syscalls.Supported("access", Access), + 22: syscalls.Supported("pipe", Pipe), + 23: syscalls.Supported("select", Select), + 24: syscalls.Supported("sched_yield", SchedYield), + 25: syscalls.Supported("mremap", Mremap), + 26: syscalls.PartiallySupported("msync", Msync, "Full data flush is not guaranteed at this time.", nil), + 27: syscalls.PartiallySupported("mincore", Mincore, "Stub implementation. The sandbox does not have access to this information. Reports all mapped pages are resident.", nil), + 28: syscalls.PartiallySupported("madvise", Madvise, "Options MADV_DONTNEED, MADV_DONTFORK are supported. Other advice is ignored.", nil), + 29: syscalls.PartiallySupported("shmget", Shmget, "Option SHM_HUGETLB is not supported.", nil), + 30: syscalls.PartiallySupported("shmat", Shmat, "Option SHM_RND is not supported.", nil), + 31: syscalls.PartiallySupported("shmctl", Shmctl, "Options SHM_LOCK, SHM_UNLOCK are not supported.", nil), + 32: syscalls.Supported("dup", Dup), + 33: syscalls.Supported("dup2", Dup2), + 34: syscalls.Supported("pause", Pause), + 35: syscalls.Supported("nanosleep", Nanosleep), + 36: syscalls.Supported("getitimer", Getitimer), + 37: syscalls.Supported("alarm", Alarm), + 38: syscalls.Supported("setitimer", Setitimer), + 39: syscalls.Supported("getpid", Getpid), + 40: syscalls.Supported("sendfile", Sendfile), + 41: syscalls.PartiallySupported("socket", Socket, "Limited support for AF_NETLINK, NETLINK_ROUTE sockets. Limited support for SOCK_RAW.", nil), + 42: syscalls.Supported("connect", Connect), + 43: syscalls.Supported("accept", Accept), + 44: syscalls.Supported("sendto", SendTo), + 45: syscalls.Supported("recvfrom", RecvFrom), + 46: syscalls.Supported("sendmsg", SendMsg), + 47: syscalls.PartiallySupported("recvmsg", RecvMsg, "Not all flags and control messages are supported.", nil), + 48: syscalls.PartiallySupported("shutdown", Shutdown, "Not all flags and control messages are supported.", nil), + 49: syscalls.PartiallySupported("bind", Bind, "Autobind for abstract Unix sockets is not supported.", nil), + 50: syscalls.Supported("listen", Listen), + 51: syscalls.Supported("getsockname", GetSockName), + 52: syscalls.Supported("getpeername", GetPeerName), + 53: syscalls.Supported("socketpair", SocketPair), + 54: syscalls.PartiallySupported("setsockopt", SetSockOpt, "Not all socket options are supported.", nil), + 55: syscalls.PartiallySupported("getsockopt", GetSockOpt, "Not all socket options are supported.", nil), + 56: syscalls.PartiallySupported("clone", Clone, "Mount namespace (CLONE_NEWNS) not supported. Options CLONE_PARENT, CLONE_SYSVSEM not supported.", nil), + 57: syscalls.Supported("fork", Fork), + 58: syscalls.Supported("vfork", Vfork), + 59: syscalls.Supported("execve", Execve), + 60: syscalls.Supported("exit", Exit), + 61: syscalls.Supported("wait4", Wait4), + 62: syscalls.Supported("kill", Kill), + 63: syscalls.Supported("uname", Uname), + 64: syscalls.Supported("semget", Semget), + 65: syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil), + 66: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, IPC_STAT, SEM_STAT, SEM_STAT_ANY, GETNCNT, GETZCNT not supported.", nil), + 67: syscalls.Supported("shmdt", Shmdt), + 68: syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 69: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 70: syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 71: syscalls.ErrorWithEvent("msgctl", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 72: syscalls.PartiallySupported("fcntl", Fcntl, "Not all options are supported.", nil), + 73: syscalls.PartiallySupported("flock", Flock, "Locks are held within the sandbox only.", nil), + 74: syscalls.PartiallySupported("fsync", Fsync, "Full data flush is not guaranteed at this time.", nil), + 75: syscalls.PartiallySupported("fdatasync", Fdatasync, "Full data flush is not guaranteed at this time.", nil), + 76: syscalls.Supported("truncate", Truncate), + 77: syscalls.Supported("ftruncate", Ftruncate), + 78: syscalls.Supported("getdents", Getdents), + 79: syscalls.Supported("getcwd", Getcwd), + 80: syscalls.Supported("chdir", Chdir), + 81: syscalls.Supported("fchdir", Fchdir), + 82: syscalls.Supported("rename", Rename), + 83: syscalls.Supported("mkdir", Mkdir), + 84: syscalls.Supported("rmdir", Rmdir), + 85: syscalls.Supported("creat", Creat), + 86: syscalls.Supported("link", Link), + 87: syscalls.Supported("unlink", Unlink), + 88: syscalls.Supported("symlink", Symlink), + 89: syscalls.Supported("readlink", Readlink), + 90: syscalls.Supported("chmod", Chmod), + 91: syscalls.PartiallySupported("fchmod", Fchmod, "Options S_ISUID and S_ISGID not supported.", nil), + 92: syscalls.Supported("chown", Chown), + 93: syscalls.Supported("fchown", Fchown), + 94: syscalls.Supported("lchown", Lchown), + 95: syscalls.Supported("umask", Umask), + 96: syscalls.Supported("gettimeofday", Gettimeofday), + 97: syscalls.Supported("getrlimit", Getrlimit), + 98: syscalls.PartiallySupported("getrusage", Getrusage, "Fields ru_maxrss, ru_minflt, ru_majflt, ru_inblock, ru_oublock are not supported. Fields ru_utime and ru_stime have low precision.", nil), + 99: syscalls.PartiallySupported("sysinfo", Sysinfo, "Fields loads, sharedram, bufferram, totalswap, freeswap, totalhigh, freehigh not supported.", nil), + 100: syscalls.Supported("times", Times), + 101: syscalls.PartiallySupported("ptrace", Ptrace, "Options PTRACE_PEEKSIGINFO, PTRACE_SECCOMP_GET_FILTER not supported.", nil), + 102: syscalls.Supported("getuid", Getuid), + 103: syscalls.PartiallySupported("syslog", Syslog, "Outputs a dummy message for security reasons.", nil), + 104: syscalls.Supported("getgid", Getgid), + 105: syscalls.Supported("setuid", Setuid), + 106: syscalls.Supported("setgid", Setgid), + 107: syscalls.Supported("geteuid", Geteuid), + 108: syscalls.Supported("getegid", Getegid), + 109: syscalls.Supported("setpgid", Setpgid), + 110: syscalls.Supported("getppid", Getppid), + 111: syscalls.Supported("getpgrp", Getpgrp), + 112: syscalls.Supported("setsid", Setsid), + 113: syscalls.Supported("setreuid", Setreuid), + 114: syscalls.Supported("setregid", Setregid), + 115: syscalls.Supported("getgroups", Getgroups), + 116: syscalls.Supported("setgroups", Setgroups), + 117: syscalls.Supported("setresuid", Setresuid), + 118: syscalls.Supported("getresuid", Getresuid), + 119: syscalls.Supported("setresgid", Setresgid), + 120: syscalls.Supported("getresgid", Getresgid), + 121: syscalls.Supported("getpgid", Getpgid), + 122: syscalls.ErrorWithEvent("setfsuid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) + 123: syscalls.ErrorWithEvent("setfsgid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) + 124: syscalls.Supported("getsid", Getsid), + 125: syscalls.Supported("capget", Capget), + 126: syscalls.Supported("capset", Capset), + 127: syscalls.Supported("rt_sigpending", RtSigpending), + 128: syscalls.Supported("rt_sigtimedwait", RtSigtimedwait), + 129: syscalls.Supported("rt_sigqueueinfo", RtSigqueueinfo), + 130: syscalls.Supported("rt_sigsuspend", RtSigsuspend), + 131: syscalls.Supported("sigaltstack", Sigaltstack), + 132: syscalls.Supported("utime", Utime), + 133: syscalls.PartiallySupported("mknod", Mknod, "Device creation is not generally supported. Only regular file and FIFO creation are supported.", nil), + 134: syscalls.Error("uselib", syserror.ENOSYS, "Obsolete", nil), + 135: syscalls.ErrorWithEvent("personality", syserror.EINVAL, "Unable to change personality.", nil), + 136: syscalls.ErrorWithEvent("ustat", syserror.ENOSYS, "Needs filesystem support.", nil), + 137: syscalls.PartiallySupported("statfs", Statfs, "Depends on the backing file system implementation.", nil), + 138: syscalls.PartiallySupported("fstatfs", Fstatfs, "Depends on the backing file system implementation.", nil), + 139: syscalls.ErrorWithEvent("sysfs", syserror.ENOSYS, "", []string{"gvisor.dev/issue/165"}), + 140: syscalls.PartiallySupported("getpriority", Getpriority, "Stub implementation.", nil), + 141: syscalls.PartiallySupported("setpriority", Setpriority, "Stub implementation.", nil), + 142: syscalls.CapError("sched_setparam", linux.CAP_SYS_NICE, "", nil), + 143: syscalls.PartiallySupported("sched_getparam", SchedGetparam, "Stub implementation.", nil), + 144: syscalls.PartiallySupported("sched_setscheduler", SchedSetscheduler, "Stub implementation.", nil), + 145: syscalls.PartiallySupported("sched_getscheduler", SchedGetscheduler, "Stub implementation.", nil), + 146: syscalls.PartiallySupported("sched_get_priority_max", SchedGetPriorityMax, "Stub implementation.", nil), + 147: syscalls.PartiallySupported("sched_get_priority_min", SchedGetPriorityMin, "Stub implementation.", nil), + 148: syscalls.ErrorWithEvent("sched_rr_get_interval", syserror.EPERM, "", nil), + 149: syscalls.PartiallySupported("mlock", Mlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 150: syscalls.PartiallySupported("munlock", Munlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 151: syscalls.PartiallySupported("mlockall", Mlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 152: syscalls.PartiallySupported("munlockall", Munlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 153: syscalls.CapError("vhangup", linux.CAP_SYS_TTY_CONFIG, "", nil), + 154: syscalls.Error("modify_ldt", syserror.EPERM, "", nil), + 155: syscalls.Error("pivot_root", syserror.EPERM, "", nil), + 156: syscalls.Error("sysctl", syserror.EPERM, "Deprecated. Use /proc/sys instead.", nil), + 157: syscalls.PartiallySupported("prctl", Prctl, "Not all options are supported.", nil), + 158: syscalls.PartiallySupported("arch_prctl", ArchPrctl, "Options ARCH_GET_GS, ARCH_SET_GS not supported.", nil), + 159: syscalls.CapError("adjtimex", linux.CAP_SYS_TIME, "", nil), + 160: syscalls.PartiallySupported("setrlimit", Setrlimit, "Not all rlimits are enforced.", nil), + 161: syscalls.Supported("chroot", Chroot), + 162: syscalls.PartiallySupported("sync", Sync, "Full data flush is not guaranteed at this time.", nil), + 163: syscalls.CapError("acct", linux.CAP_SYS_PACCT, "", nil), + 164: syscalls.CapError("settimeofday", linux.CAP_SYS_TIME, "", nil), + 165: syscalls.PartiallySupported("mount", Mount, "Not all options or file systems are supported.", nil), + 166: syscalls.PartiallySupported("umount2", Umount2, "Not all options or file systems are supported.", nil), + 167: syscalls.CapError("swapon", linux.CAP_SYS_ADMIN, "", nil), + 168: syscalls.CapError("swapoff", linux.CAP_SYS_ADMIN, "", nil), + 169: syscalls.CapError("reboot", linux.CAP_SYS_BOOT, "", nil), + 170: syscalls.Supported("sethostname", Sethostname), + 171: syscalls.Supported("setdomainname", Setdomainname), + 172: syscalls.CapError("iopl", linux.CAP_SYS_RAWIO, "", nil), + 173: syscalls.CapError("ioperm", linux.CAP_SYS_RAWIO, "", nil), + 174: syscalls.CapError("create_module", linux.CAP_SYS_MODULE, "", nil), + 175: syscalls.CapError("init_module", linux.CAP_SYS_MODULE, "", nil), + 176: syscalls.CapError("delete_module", linux.CAP_SYS_MODULE, "", nil), + 177: syscalls.Error("get_kernel_syms", syserror.ENOSYS, "Not supported in Linux > 2.6.", nil), + 178: syscalls.Error("query_module", syserror.ENOSYS, "Not supported in Linux > 2.6.", nil), + 179: syscalls.CapError("quotactl", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_admin for most operations + 180: syscalls.Error("nfsservctl", syserror.ENOSYS, "Removed after Linux 3.1.", nil), + 181: syscalls.Error("getpmsg", syserror.ENOSYS, "Not implemented in Linux.", nil), + 182: syscalls.Error("putpmsg", syserror.ENOSYS, "Not implemented in Linux.", nil), + 183: syscalls.Error("afs_syscall", syserror.ENOSYS, "Not implemented in Linux.", nil), + 184: syscalls.Error("tuxcall", syserror.ENOSYS, "Not implemented in Linux.", nil), + 185: syscalls.Error("security", syserror.ENOSYS, "Not implemented in Linux.", nil), + 186: syscalls.Supported("gettid", Gettid), + 187: syscalls.Supported("readahead", Readahead), + 188: syscalls.PartiallySupported("setxattr", SetXattr, "Only supported for tmpfs.", nil), + 189: syscalls.PartiallySupported("lsetxattr", LSetXattr, "Only supported for tmpfs.", nil), + 190: syscalls.PartiallySupported("fsetxattr", FSetXattr, "Only supported for tmpfs.", nil), + 191: syscalls.PartiallySupported("getxattr", GetXattr, "Only supported for tmpfs.", nil), + 192: syscalls.PartiallySupported("lgetxattr", LGetXattr, "Only supported for tmpfs.", nil), + 193: syscalls.PartiallySupported("fgetxattr", FGetXattr, "Only supported for tmpfs.", nil), + 194: syscalls.PartiallySupported("listxattr", ListXattr, "Only supported for tmpfs", nil), + 195: syscalls.PartiallySupported("llistxattr", LListXattr, "Only supported for tmpfs", nil), + 196: syscalls.PartiallySupported("flistxattr", FListXattr, "Only supported for tmpfs", nil), + 197: syscalls.PartiallySupported("removexattr", RemoveXattr, "Only supported for tmpfs", nil), + 198: syscalls.PartiallySupported("lremovexattr", LRemoveXattr, "Only supported for tmpfs", nil), + 199: syscalls.PartiallySupported("fremovexattr", FRemoveXattr, "Only supported for tmpfs", nil), + 200: syscalls.Supported("tkill", Tkill), + 201: syscalls.Supported("time", Time), + 202: syscalls.PartiallySupported("futex", Futex, "Robust futexes not supported.", nil), + 203: syscalls.PartiallySupported("sched_setaffinity", SchedSetaffinity, "Stub implementation.", nil), + 204: syscalls.PartiallySupported("sched_getaffinity", SchedGetaffinity, "Stub implementation.", nil), + 205: syscalls.Error("set_thread_area", syserror.ENOSYS, "Expected to return ENOSYS on 64-bit", nil), + 206: syscalls.PartiallySupported("io_setup", IoSetup, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 207: syscalls.PartiallySupported("io_destroy", IoDestroy, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 208: syscalls.PartiallySupported("io_getevents", IoGetevents, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 209: syscalls.PartiallySupported("io_submit", IoSubmit, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 210: syscalls.PartiallySupported("io_cancel", IoCancel, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 211: syscalls.Error("get_thread_area", syserror.ENOSYS, "Expected to return ENOSYS on 64-bit", nil), + 212: syscalls.CapError("lookup_dcookie", linux.CAP_SYS_ADMIN, "", nil), + 213: syscalls.Supported("epoll_create", EpollCreate), + 214: syscalls.ErrorWithEvent("epoll_ctl_old", syserror.ENOSYS, "Deprecated.", nil), + 215: syscalls.ErrorWithEvent("epoll_wait_old", syserror.ENOSYS, "Deprecated.", nil), + 216: syscalls.ErrorWithEvent("remap_file_pages", syserror.ENOSYS, "Deprecated since Linux 3.16.", nil), + 217: syscalls.Supported("getdents64", Getdents64), + 218: syscalls.Supported("set_tid_address", SetTidAddress), + 219: syscalls.Supported("restart_syscall", RestartSyscall), + 220: syscalls.ErrorWithEvent("semtimedop", syserror.ENOSYS, "", []string{"gvisor.dev/issue/137"}), + 221: syscalls.PartiallySupported("fadvise64", Fadvise64, "Not all options are supported.", nil), + 222: syscalls.Supported("timer_create", TimerCreate), + 223: syscalls.Supported("timer_settime", TimerSettime), + 224: syscalls.Supported("timer_gettime", TimerGettime), + 225: syscalls.Supported("timer_getoverrun", TimerGetoverrun), + 226: syscalls.Supported("timer_delete", TimerDelete), + 227: syscalls.Supported("clock_settime", ClockSettime), + 228: syscalls.Supported("clock_gettime", ClockGettime), + 229: syscalls.Supported("clock_getres", ClockGetres), + 230: syscalls.Supported("clock_nanosleep", ClockNanosleep), + 231: syscalls.Supported("exit_group", ExitGroup), + 232: syscalls.Supported("epoll_wait", EpollWait), + 233: syscalls.Supported("epoll_ctl", EpollCtl), + 234: syscalls.Supported("tgkill", Tgkill), + 235: syscalls.Supported("utimes", Utimes), + 236: syscalls.Error("vserver", syserror.ENOSYS, "Not implemented by Linux", nil), + 237: syscalls.PartiallySupported("mbind", Mbind, "Stub implementation. Only a single NUMA node is advertised, and mempolicy is ignored accordingly, but mbind() will succeed and has effects reflected by get_mempolicy.", []string{"gvisor.dev/issue/262"}), + 238: syscalls.PartiallySupported("set_mempolicy", SetMempolicy, "Stub implementation.", nil), + 239: syscalls.PartiallySupported("get_mempolicy", GetMempolicy, "Stub implementation.", nil), + 240: syscalls.ErrorWithEvent("mq_open", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 241: syscalls.ErrorWithEvent("mq_unlink", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 242: syscalls.ErrorWithEvent("mq_timedsend", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 243: syscalls.ErrorWithEvent("mq_timedreceive", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 244: syscalls.ErrorWithEvent("mq_notify", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 245: syscalls.ErrorWithEvent("mq_getsetattr", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 246: syscalls.CapError("kexec_load", linux.CAP_SYS_BOOT, "", nil), + 247: syscalls.Supported("waitid", Waitid), + 248: syscalls.Error("add_key", syserror.EACCES, "Not available to user.", nil), + 249: syscalls.Error("request_key", syserror.EACCES, "Not available to user.", nil), + 250: syscalls.Error("keyctl", syserror.EACCES, "Not available to user.", nil), + 251: syscalls.CapError("ioprio_set", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) + 252: syscalls.CapError("ioprio_get", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) + 253: syscalls.PartiallySupported("inotify_init", InotifyInit, "inotify events are only available inside the sandbox.", nil), + 254: syscalls.PartiallySupported("inotify_add_watch", InotifyAddWatch, "inotify events are only available inside the sandbox.", nil), + 255: syscalls.PartiallySupported("inotify_rm_watch", InotifyRmWatch, "inotify events are only available inside the sandbox.", nil), + 256: syscalls.CapError("migrate_pages", linux.CAP_SYS_NICE, "", nil), + 257: syscalls.Supported("openat", Openat), + 258: syscalls.Supported("mkdirat", Mkdirat), + 259: syscalls.Supported("mknodat", Mknodat), + 260: syscalls.Supported("fchownat", Fchownat), + 261: syscalls.Supported("futimesat", Futimesat), + 262: syscalls.Supported("fstatat", Fstatat), + 263: syscalls.Supported("unlinkat", Unlinkat), + 264: syscalls.Supported("renameat", Renameat), + 265: syscalls.Supported("linkat", Linkat), + 266: syscalls.Supported("symlinkat", Symlinkat), + 267: syscalls.Supported("readlinkat", Readlinkat), + 268: syscalls.Supported("fchmodat", Fchmodat), + 269: syscalls.Supported("faccessat", Faccessat), + 270: syscalls.Supported("pselect", Pselect), + 271: syscalls.Supported("ppoll", Ppoll), + 272: syscalls.PartiallySupported("unshare", Unshare, "Mount, cgroup namespaces not supported. Network namespaces supported but must be empty.", nil), + 273: syscalls.Supported("set_robust_list", SetRobustList), + 274: syscalls.Supported("get_robust_list", GetRobustList), + 275: syscalls.Supported("splice", Splice), + 276: syscalls.Supported("tee", Tee), + 277: syscalls.PartiallySupported("sync_file_range", SyncFileRange, "Full data flush is not guaranteed at this time.", nil), + 278: syscalls.ErrorWithEvent("vmsplice", syserror.ENOSYS, "", []string{"gvisor.dev/issue/138"}), // TODO(b/29354098) + 279: syscalls.CapError("move_pages", linux.CAP_SYS_NICE, "", nil), // requires cap_sys_nice (mostly) + 280: syscalls.Supported("utimensat", Utimensat), + 281: syscalls.Supported("epoll_pwait", EpollPwait), + 282: syscalls.PartiallySupported("signalfd", Signalfd, "Semantics are slightly different.", []string{"gvisor.dev/issue/139"}), + 283: syscalls.Supported("timerfd_create", TimerfdCreate), + 284: syscalls.Supported("eventfd", Eventfd), + 285: syscalls.PartiallySupported("fallocate", Fallocate, "Not all options are supported.", nil), + 286: syscalls.Supported("timerfd_settime", TimerfdSettime), + 287: syscalls.Supported("timerfd_gettime", TimerfdGettime), + 288: syscalls.Supported("accept4", Accept4), + 289: syscalls.PartiallySupported("signalfd4", Signalfd4, "Semantics are slightly different.", []string{"gvisor.dev/issue/139"}), + 290: syscalls.Supported("eventfd2", Eventfd2), + 291: syscalls.Supported("epoll_create1", EpollCreate1), + 292: syscalls.Supported("dup3", Dup3), + 293: syscalls.Supported("pipe2", Pipe2), + 294: syscalls.Supported("inotify_init1", InotifyInit1), + 295: syscalls.Supported("preadv", Preadv), + 296: syscalls.Supported("pwritev", Pwritev), + 297: syscalls.Supported("rt_tgsigqueueinfo", RtTgsigqueueinfo), + 298: syscalls.ErrorWithEvent("perf_event_open", syserror.ENODEV, "No support for perf counters", nil), + 299: syscalls.PartiallySupported("recvmmsg", RecvMMsg, "Not all flags and control messages are supported.", nil), + 300: syscalls.ErrorWithEvent("fanotify_init", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), + 301: syscalls.ErrorWithEvent("fanotify_mark", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), + 302: syscalls.Supported("prlimit64", Prlimit64), + 303: syscalls.Error("name_to_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), + 304: syscalls.Error("open_by_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), + 305: syscalls.CapError("clock_adjtime", linux.CAP_SYS_TIME, "", nil), + 306: syscalls.PartiallySupported("syncfs", Syncfs, "Depends on backing file system.", nil), + 307: syscalls.PartiallySupported("sendmmsg", SendMMsg, "Not all flags and control messages are supported.", nil), + 308: syscalls.ErrorWithEvent("setns", syserror.EOPNOTSUPP, "Needs filesystem support", []string{"gvisor.dev/issue/140"}), // TODO(b/29354995) + 309: syscalls.Supported("getcpu", Getcpu), + 310: syscalls.ErrorWithEvent("process_vm_readv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), + 311: syscalls.ErrorWithEvent("process_vm_writev", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), + 312: syscalls.CapError("kcmp", linux.CAP_SYS_PTRACE, "", nil), + 313: syscalls.CapError("finit_module", linux.CAP_SYS_MODULE, "", nil), + 314: syscalls.ErrorWithEvent("sched_setattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) + 315: syscalls.ErrorWithEvent("sched_getattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) + 316: syscalls.ErrorWithEvent("renameat2", syserror.ENOSYS, "", []string{"gvisor.dev/issue/263"}), // TODO(b/118902772) + 317: syscalls.Supported("seccomp", Seccomp), + 318: syscalls.Supported("getrandom", GetRandom), + 319: syscalls.Supported("memfd_create", MemfdCreate), + 320: syscalls.CapError("kexec_file_load", linux.CAP_SYS_BOOT, "", nil), + 321: syscalls.CapError("bpf", linux.CAP_SYS_ADMIN, "", nil), + 322: syscalls.Supported("execveat", Execveat), + 323: syscalls.ErrorWithEvent("userfaultfd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/266"}), // TODO(b/118906345) + 324: syscalls.ErrorWithEvent("membarrier", syserror.ENOSYS, "", []string{"gvisor.dev/issue/267"}), // TODO(gvisor.dev/issue/267) + 325: syscalls.PartiallySupported("mlock2", Mlock2, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + + // Syscalls implemented after 325 are "backports" from versions + // of Linux after 4.4. + 326: syscalls.ErrorWithEvent("copy_file_range", syserror.ENOSYS, "", nil), + 327: syscalls.Supported("preadv2", Preadv2), + 328: syscalls.PartiallySupported("pwritev2", Pwritev2, "Flag RWF_HIPRI is not supported.", nil), + 329: syscalls.ErrorWithEvent("pkey_mprotect", syserror.ENOSYS, "", nil), + 330: syscalls.ErrorWithEvent("pkey_alloc", syserror.ENOSYS, "", nil), + 331: syscalls.ErrorWithEvent("pkey_free", syserror.ENOSYS, "", nil), + 332: syscalls.Supported("statx", Statx), + 333: syscalls.ErrorWithEvent("io_pgetevents", syserror.ENOSYS, "", nil), + 334: syscalls.PartiallySupported("rseq", RSeq, "Not supported on all platforms.", nil), + + // Linux skips ahead to syscall 424 to sync numbers between arches. + 424: syscalls.ErrorWithEvent("pidfd_send_signal", syserror.ENOSYS, "", nil), + 425: syscalls.ErrorWithEvent("io_uring_setup", syserror.ENOSYS, "", nil), + 426: syscalls.ErrorWithEvent("io_uring_enter", syserror.ENOSYS, "", nil), + 427: syscalls.ErrorWithEvent("io_uring_register", syserror.ENOSYS, "", nil), + 428: syscalls.ErrorWithEvent("open_tree", syserror.ENOSYS, "", nil), + 429: syscalls.ErrorWithEvent("move_mount", syserror.ENOSYS, "", nil), + 430: syscalls.ErrorWithEvent("fsopen", syserror.ENOSYS, "", nil), + 431: syscalls.ErrorWithEvent("fsconfig", syserror.ENOSYS, "", nil), + 432: syscalls.ErrorWithEvent("fsmount", syserror.ENOSYS, "", nil), + 433: syscalls.ErrorWithEvent("fspick", syserror.ENOSYS, "", nil), + 434: syscalls.ErrorWithEvent("pidfd_open", syserror.ENOSYS, "", nil), + 435: syscalls.ErrorWithEvent("clone3", syserror.ENOSYS, "", nil), + }, + Emulate: map[usermem.Addr]uintptr{ + 0xffffffffff600000: 96, // vsyscall gettimeofday(2) + 0xffffffffff600400: 201, // vsyscall time(2) + 0xffffffffff600800: 309, // vsyscall getcpu(2) + }, + Missing: func(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, error) { + t.Kernel().EmitUnimplementedEvent(t) + return 0, syserror.ENOSYS + }, +} + +// ARM64 is a table of Linux arm64 syscall API with the corresponding syscall +// numbers from Linux 4.4. +var ARM64 = &kernel.SyscallTable{ + OS: abi.Linux, + Arch: arch.ARM64, + Version: kernel.Version{ + Sysname: LinuxSysname, + Release: LinuxRelease, + Version: LinuxVersion, + }, + AuditNumber: linux.AUDIT_ARCH_AARCH64, + Table: map[uintptr]kernel.Syscall{ + 0: syscalls.PartiallySupported("io_setup", IoSetup, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 1: syscalls.PartiallySupported("io_destroy", IoDestroy, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 2: syscalls.PartiallySupported("io_submit", IoSubmit, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 3: syscalls.PartiallySupported("io_cancel", IoCancel, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 4: syscalls.PartiallySupported("io_getevents", IoGetevents, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), + 5: syscalls.PartiallySupported("setxattr", SetXattr, "Only supported for tmpfs.", nil), + 6: syscalls.PartiallySupported("lsetxattr", LSetXattr, "Only supported for tmpfs.", nil), + 7: syscalls.PartiallySupported("fsetxattr", FSetXattr, "Only supported for tmpfs.", nil), + 8: syscalls.PartiallySupported("getxattr", GetXattr, "Only supported for tmpfs.", nil), + 9: syscalls.PartiallySupported("lgetxattr", LGetXattr, "Only supported for tmpfs.", nil), + 10: syscalls.PartiallySupported("fgetxattr", FGetXattr, "Only supported for tmpfs.", nil), + 11: syscalls.PartiallySupported("listxattr", ListXattr, "Only supported for tmpfs", nil), + 12: syscalls.PartiallySupported("llistxattr", LListXattr, "Only supported for tmpfs", nil), + 13: syscalls.PartiallySupported("flistxattr", FListXattr, "Only supported for tmpfs", nil), + 14: syscalls.PartiallySupported("removexattr", RemoveXattr, "Only supported for tmpfs", nil), + 15: syscalls.PartiallySupported("lremovexattr", LRemoveXattr, "Only supported for tmpfs", nil), + 16: syscalls.PartiallySupported("fremovexattr", FRemoveXattr, "Only supported for tmpfs", nil), + 17: syscalls.Supported("getcwd", Getcwd), + 18: syscalls.CapError("lookup_dcookie", linux.CAP_SYS_ADMIN, "", nil), + 19: syscalls.Supported("eventfd2", Eventfd2), + 20: syscalls.Supported("epoll_create1", EpollCreate1), + 21: syscalls.Supported("epoll_ctl", EpollCtl), + 22: syscalls.Supported("epoll_pwait", EpollPwait), + 23: syscalls.Supported("dup", Dup), + 24: syscalls.Supported("dup3", Dup3), + 25: syscalls.PartiallySupported("fcntl", Fcntl, "Not all options are supported.", nil), + 26: syscalls.Supported("inotify_init1", InotifyInit1), + 27: syscalls.PartiallySupported("inotify_add_watch", InotifyAddWatch, "inotify events are only available inside the sandbox.", nil), + 28: syscalls.PartiallySupported("inotify_rm_watch", InotifyRmWatch, "inotify events are only available inside the sandbox.", nil), + 29: syscalls.PartiallySupported("ioctl", Ioctl, "Only a few ioctls are implemented for backing devices and file systems.", nil), + 30: syscalls.CapError("ioprio_set", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) + 31: syscalls.CapError("ioprio_get", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) + 32: syscalls.PartiallySupported("flock", Flock, "Locks are held within the sandbox only.", nil), + 33: syscalls.Supported("mknodat", Mknodat), + 34: syscalls.Supported("mkdirat", Mkdirat), + 35: syscalls.Supported("unlinkat", Unlinkat), + 36: syscalls.Supported("symlinkat", Symlinkat), + 37: syscalls.Supported("linkat", Linkat), + 38: syscalls.Supported("renameat", Renameat), + 39: syscalls.PartiallySupported("umount2", Umount2, "Not all options or file systems are supported.", nil), + 40: syscalls.PartiallySupported("mount", Mount, "Not all options or file systems are supported.", nil), + 41: syscalls.Error("pivot_root", syserror.EPERM, "", nil), + 42: syscalls.Error("nfsservctl", syserror.ENOSYS, "Removed after Linux 3.1.", nil), + 43: syscalls.PartiallySupported("statfs", Statfs, "Depends on the backing file system implementation.", nil), + 44: syscalls.PartiallySupported("fstatfs", Fstatfs, "Depends on the backing file system implementation.", nil), + 45: syscalls.Supported("truncate", Truncate), + 46: syscalls.Supported("ftruncate", Ftruncate), + 47: syscalls.PartiallySupported("fallocate", Fallocate, "Not all options are supported.", nil), + 48: syscalls.Supported("faccessat", Faccessat), + 49: syscalls.Supported("chdir", Chdir), + 50: syscalls.Supported("fchdir", Fchdir), + 51: syscalls.Supported("chroot", Chroot), + 52: syscalls.PartiallySupported("fchmod", Fchmod, "Options S_ISUID and S_ISGID not supported.", nil), + 53: syscalls.Supported("fchmodat", Fchmodat), + 54: syscalls.Supported("fchownat", Fchownat), + 55: syscalls.Supported("fchown", Fchown), + 56: syscalls.Supported("openat", Openat), + 57: syscalls.Supported("close", Close), + 58: syscalls.CapError("vhangup", linux.CAP_SYS_TTY_CONFIG, "", nil), + 59: syscalls.Supported("pipe2", Pipe2), + 60: syscalls.CapError("quotactl", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_admin for most operations + 61: syscalls.Supported("getdents64", Getdents64), + 62: syscalls.Supported("lseek", Lseek), + 63: syscalls.Supported("read", Read), + 64: syscalls.Supported("write", Write), + 65: syscalls.Supported("readv", Readv), + 66: syscalls.Supported("writev", Writev), + 67: syscalls.Supported("pread64", Pread64), + 68: syscalls.Supported("pwrite64", Pwrite64), + 69: syscalls.Supported("preadv", Preadv), + 70: syscalls.Supported("pwritev", Pwritev), + 71: syscalls.Supported("sendfile", Sendfile), + 72: syscalls.Supported("pselect", Pselect), + 73: syscalls.Supported("ppoll", Ppoll), + 74: syscalls.PartiallySupported("signalfd4", Signalfd4, "Semantics are slightly different.", []string{"gvisor.dev/issue/139"}), + 75: syscalls.ErrorWithEvent("vmsplice", syserror.ENOSYS, "", []string{"gvisor.dev/issue/138"}), // TODO(b/29354098) + 76: syscalls.PartiallySupported("splice", Splice, "Stub implementation.", []string{"gvisor.dev/issue/138"}), // TODO(b/29354098) + 77: syscalls.Supported("tee", Tee), + 78: syscalls.Supported("readlinkat", Readlinkat), + 79: syscalls.Supported("fstatat", Fstatat), + 80: syscalls.Supported("fstat", Fstat), + 81: syscalls.PartiallySupported("sync", Sync, "Full data flush is not guaranteed at this time.", nil), + 82: syscalls.PartiallySupported("fsync", Fsync, "Full data flush is not guaranteed at this time.", nil), + 83: syscalls.PartiallySupported("fdatasync", Fdatasync, "Full data flush is not guaranteed at this time.", nil), + 84: syscalls.PartiallySupported("sync_file_range", SyncFileRange, "Full data flush is not guaranteed at this time.", nil), + 85: syscalls.Supported("timerfd_create", TimerfdCreate), + 86: syscalls.Supported("timerfd_settime", TimerfdSettime), + 87: syscalls.Supported("timerfd_gettime", TimerfdGettime), + 88: syscalls.Supported("utimensat", Utimensat), + 89: syscalls.CapError("acct", linux.CAP_SYS_PACCT, "", nil), + 90: syscalls.Supported("capget", Capget), + 91: syscalls.Supported("capset", Capset), + 92: syscalls.ErrorWithEvent("personality", syserror.EINVAL, "Unable to change personality.", nil), + 93: syscalls.Supported("exit", Exit), + 94: syscalls.Supported("exit_group", ExitGroup), + 95: syscalls.Supported("waitid", Waitid), + 96: syscalls.Supported("set_tid_address", SetTidAddress), + 97: syscalls.PartiallySupported("unshare", Unshare, "Mount, cgroup namespaces not supported. Network namespaces supported but must be empty.", nil), + 98: syscalls.PartiallySupported("futex", Futex, "Robust futexes not supported.", nil), + 99: syscalls.Error("set_robust_list", syserror.ENOSYS, "Obsolete.", nil), + 100: syscalls.Error("get_robust_list", syserror.ENOSYS, "Obsolete.", nil), + 101: syscalls.Supported("nanosleep", Nanosleep), + 102: syscalls.Supported("getitimer", Getitimer), + 103: syscalls.Supported("setitimer", Setitimer), + 104: syscalls.CapError("kexec_load", linux.CAP_SYS_BOOT, "", nil), + 105: syscalls.CapError("init_module", linux.CAP_SYS_MODULE, "", nil), + 106: syscalls.CapError("delete_module", linux.CAP_SYS_MODULE, "", nil), + 107: syscalls.Supported("timer_create", TimerCreate), + 108: syscalls.Supported("timer_gettime", TimerGettime), + 109: syscalls.Supported("timer_getoverrun", TimerGetoverrun), + 110: syscalls.Supported("timer_settime", TimerSettime), + 111: syscalls.Supported("timer_delete", TimerDelete), + 112: syscalls.Supported("clock_settime", ClockSettime), + 113: syscalls.Supported("clock_gettime", ClockGettime), + 114: syscalls.Supported("clock_getres", ClockGetres), + 115: syscalls.Supported("clock_nanosleep", ClockNanosleep), + 116: syscalls.PartiallySupported("syslog", Syslog, "Outputs a dummy message for security reasons.", nil), + 117: syscalls.PartiallySupported("ptrace", Ptrace, "Options PTRACE_PEEKSIGINFO, PTRACE_SECCOMP_GET_FILTER not supported.", nil), + 118: syscalls.CapError("sched_setparam", linux.CAP_SYS_NICE, "", nil), + 119: syscalls.PartiallySupported("sched_setscheduler", SchedSetscheduler, "Stub implementation.", nil), + 120: syscalls.PartiallySupported("sched_getscheduler", SchedGetscheduler, "Stub implementation.", nil), + 121: syscalls.PartiallySupported("sched_getparam", SchedGetparam, "Stub implementation.", nil), + 122: syscalls.PartiallySupported("sched_setaffinity", SchedSetaffinity, "Stub implementation.", nil), + 123: syscalls.PartiallySupported("sched_getaffinity", SchedGetaffinity, "Stub implementation.", nil), + 124: syscalls.Supported("sched_yield", SchedYield), + 125: syscalls.PartiallySupported("sched_get_priority_max", SchedGetPriorityMax, "Stub implementation.", nil), + 126: syscalls.PartiallySupported("sched_get_priority_min", SchedGetPriorityMin, "Stub implementation.", nil), + 127: syscalls.ErrorWithEvent("sched_rr_get_interval", syserror.EPERM, "", nil), + 128: syscalls.Supported("restart_syscall", RestartSyscall), + 129: syscalls.Supported("kill", Kill), + 130: syscalls.Supported("tkill", Tkill), + 131: syscalls.Supported("tgkill", Tgkill), + 132: syscalls.Supported("sigaltstack", Sigaltstack), + 133: syscalls.Supported("rt_sigsuspend", RtSigsuspend), + 134: syscalls.Supported("rt_sigaction", RtSigaction), + 135: syscalls.Supported("rt_sigprocmask", RtSigprocmask), + 136: syscalls.Supported("rt_sigpending", RtSigpending), + 137: syscalls.Supported("rt_sigtimedwait", RtSigtimedwait), + 138: syscalls.Supported("rt_sigqueueinfo", RtSigqueueinfo), + 139: syscalls.Supported("rt_sigreturn", RtSigreturn), + 140: syscalls.PartiallySupported("setpriority", Setpriority, "Stub implementation.", nil), + 141: syscalls.PartiallySupported("getpriority", Getpriority, "Stub implementation.", nil), + 142: syscalls.CapError("reboot", linux.CAP_SYS_BOOT, "", nil), + 143: syscalls.Supported("setregid", Setregid), + 144: syscalls.Supported("setgid", Setgid), + 145: syscalls.Supported("setreuid", Setreuid), + 146: syscalls.Supported("setuid", Setuid), + 147: syscalls.Supported("setresuid", Setresuid), + 148: syscalls.Supported("getresuid", Getresuid), + 149: syscalls.Supported("setresgid", Setresgid), + 150: syscalls.Supported("getresgid", Getresgid), + 151: syscalls.ErrorWithEvent("setfsuid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) + 152: syscalls.ErrorWithEvent("setfsgid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) + 153: syscalls.Supported("times", Times), + 154: syscalls.Supported("setpgid", Setpgid), + 155: syscalls.Supported("getpgid", Getpgid), + 156: syscalls.Supported("getsid", Getsid), + 157: syscalls.Supported("setsid", Setsid), + 158: syscalls.Supported("getgroups", Getgroups), + 159: syscalls.Supported("setgroups", Setgroups), + 160: syscalls.Supported("uname", Uname), + 161: syscalls.Supported("sethostname", Sethostname), + 162: syscalls.Supported("setdomainname", Setdomainname), + 163: syscalls.Supported("getrlimit", Getrlimit), + 164: syscalls.PartiallySupported("setrlimit", Setrlimit, "Not all rlimits are enforced.", nil), + 165: syscalls.PartiallySupported("getrusage", Getrusage, "Fields ru_maxrss, ru_minflt, ru_majflt, ru_inblock, ru_oublock are not supported. Fields ru_utime and ru_stime have low precision.", nil), + 166: syscalls.Supported("umask", Umask), + 167: syscalls.PartiallySupported("prctl", Prctl, "Not all options are supported.", nil), + 168: syscalls.Supported("getcpu", Getcpu), + 169: syscalls.Supported("gettimeofday", Gettimeofday), + 170: syscalls.CapError("settimeofday", linux.CAP_SYS_TIME, "", nil), + 171: syscalls.CapError("adjtimex", linux.CAP_SYS_TIME, "", nil), + 172: syscalls.Supported("getpid", Getpid), + 173: syscalls.Supported("getppid", Getppid), + 174: syscalls.Supported("getuid", Getuid), + 175: syscalls.Supported("geteuid", Geteuid), + 176: syscalls.Supported("getgid", Getgid), + 177: syscalls.Supported("getegid", Getegid), + 178: syscalls.Supported("gettid", Gettid), + 179: syscalls.PartiallySupported("sysinfo", Sysinfo, "Fields loads, sharedram, bufferram, totalswap, freeswap, totalhigh, freehigh not supported.", nil), + 180: syscalls.ErrorWithEvent("mq_open", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 181: syscalls.ErrorWithEvent("mq_unlink", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 182: syscalls.ErrorWithEvent("mq_timedsend", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 183: syscalls.ErrorWithEvent("mq_timedreceive", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 184: syscalls.ErrorWithEvent("mq_notify", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 185: syscalls.ErrorWithEvent("mq_getsetattr", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) + 186: syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 187: syscalls.ErrorWithEvent("msgctl", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 188: syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 189: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) + 190: syscalls.Supported("semget", Semget), + 191: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, IPC_STAT, SEM_STAT, SEM_STAT_ANY, GETNCNT, GETZCNT not supported.", nil), + 192: syscalls.ErrorWithEvent("semtimedop", syserror.ENOSYS, "", []string{"gvisor.dev/issue/137"}), + 193: syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil), + 194: syscalls.PartiallySupported("shmget", Shmget, "Option SHM_HUGETLB is not supported.", nil), + 195: syscalls.PartiallySupported("shmctl", Shmctl, "Options SHM_LOCK, SHM_UNLOCK are not supported.", nil), + 196: syscalls.PartiallySupported("shmat", Shmat, "Option SHM_RND is not supported.", nil), + 197: syscalls.Supported("shmdt", Shmdt), + 198: syscalls.PartiallySupported("socket", Socket, "Limited support for AF_NETLINK, NETLINK_ROUTE sockets. Limited support for SOCK_RAW.", nil), + 199: syscalls.Supported("socketpair", SocketPair), + 200: syscalls.PartiallySupported("bind", Bind, "Autobind for abstract Unix sockets is not supported.", nil), + 201: syscalls.Supported("listen", Listen), + 202: syscalls.Supported("accept", Accept), + 203: syscalls.Supported("connect", Connect), + 204: syscalls.Supported("getsockname", GetSockName), + 205: syscalls.Supported("getpeername", GetPeerName), + 206: syscalls.Supported("sendto", SendTo), + 207: syscalls.Supported("recvfrom", RecvFrom), + 208: syscalls.PartiallySupported("setsockopt", SetSockOpt, "Not all socket options are supported.", nil), + 209: syscalls.PartiallySupported("getsockopt", GetSockOpt, "Not all socket options are supported.", nil), + 210: syscalls.PartiallySupported("shutdown", Shutdown, "Not all flags and control messages are supported.", nil), + 211: syscalls.Supported("sendmsg", SendMsg), + 212: syscalls.PartiallySupported("recvmsg", RecvMsg, "Not all flags and control messages are supported.", nil), + 213: syscalls.Supported("readahead", Readahead), + 214: syscalls.Supported("brk", Brk), + 215: syscalls.Supported("munmap", Munmap), + 216: syscalls.Supported("mremap", Mremap), + 217: syscalls.Error("add_key", syserror.EACCES, "Not available to user.", nil), + 218: syscalls.Error("request_key", syserror.EACCES, "Not available to user.", nil), + 219: syscalls.Error("keyctl", syserror.EACCES, "Not available to user.", nil), + 220: syscalls.PartiallySupported("clone", Clone, "Mount namespace (CLONE_NEWNS) not supported. Options CLONE_PARENT, CLONE_SYSVSEM not supported.", nil), + 221: syscalls.Supported("execve", Execve), + 222: syscalls.PartiallySupported("mmap", Mmap, "Generally supported with exceptions. Options MAP_FIXED_NOREPLACE, MAP_SHARED_VALIDATE, MAP_SYNC MAP_GROWSDOWN, MAP_HUGETLB are not supported.", nil), + 223: syscalls.PartiallySupported("fadvise64", Fadvise64, "Not all options are supported.", nil), + 224: syscalls.CapError("swapon", linux.CAP_SYS_ADMIN, "", nil), + 225: syscalls.CapError("swapoff", linux.CAP_SYS_ADMIN, "", nil), + 226: syscalls.Supported("mprotect", Mprotect), + 227: syscalls.PartiallySupported("msync", Msync, "Full data flush is not guaranteed at this time.", nil), + 228: syscalls.PartiallySupported("mlock", Mlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 229: syscalls.PartiallySupported("munlock", Munlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 230: syscalls.PartiallySupported("mlockall", Mlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 231: syscalls.PartiallySupported("munlockall", Munlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + 232: syscalls.PartiallySupported("mincore", Mincore, "Stub implementation. The sandbox does not have access to this information. Reports all mapped pages are resident.", nil), + 233: syscalls.PartiallySupported("madvise", Madvise, "Options MADV_DONTNEED, MADV_DONTFORK are supported. Other advice is ignored.", nil), + 234: syscalls.ErrorWithEvent("remap_file_pages", syserror.ENOSYS, "Deprecated since Linux 3.16.", nil), + 235: syscalls.PartiallySupported("mbind", Mbind, "Stub implementation. Only a single NUMA node is advertised, and mempolicy is ignored accordingly, but mbind() will succeed and has effects reflected by get_mempolicy.", []string{"gvisor.dev/issue/262"}), + 236: syscalls.PartiallySupported("get_mempolicy", GetMempolicy, "Stub implementation.", nil), + 237: syscalls.PartiallySupported("set_mempolicy", SetMempolicy, "Stub implementation.", nil), + 238: syscalls.CapError("migrate_pages", linux.CAP_SYS_NICE, "", nil), + 239: syscalls.CapError("move_pages", linux.CAP_SYS_NICE, "", nil), // requires cap_sys_nice (mostly) + 240: syscalls.Supported("rt_tgsigqueueinfo", RtTgsigqueueinfo), + 241: syscalls.ErrorWithEvent("perf_event_open", syserror.ENODEV, "No support for perf counters", nil), + 242: syscalls.Supported("accept4", Accept4), + 243: syscalls.PartiallySupported("recvmmsg", RecvMMsg, "Not all flags and control messages are supported.", nil), + 260: syscalls.Supported("wait4", Wait4), + 261: syscalls.Supported("prlimit64", Prlimit64), + 262: syscalls.ErrorWithEvent("fanotify_init", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), + 263: syscalls.ErrorWithEvent("fanotify_mark", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), + 264: syscalls.Error("name_to_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), + 265: syscalls.Error("open_by_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), + 266: syscalls.CapError("clock_adjtime", linux.CAP_SYS_TIME, "", nil), + 267: syscalls.PartiallySupported("syncfs", Syncfs, "Depends on backing file system.", nil), + 268: syscalls.ErrorWithEvent("setns", syserror.EOPNOTSUPP, "Needs filesystem support", []string{"gvisor.dev/issue/140"}), // TODO(b/29354995) + 269: syscalls.PartiallySupported("sendmmsg", SendMMsg, "Not all flags and control messages are supported.", nil), + 270: syscalls.ErrorWithEvent("process_vm_readv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), + 271: syscalls.ErrorWithEvent("process_vm_writev", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), + 272: syscalls.CapError("kcmp", linux.CAP_SYS_PTRACE, "", nil), + 273: syscalls.CapError("finit_module", linux.CAP_SYS_MODULE, "", nil), + 274: syscalls.ErrorWithEvent("sched_setattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) + 275: syscalls.ErrorWithEvent("sched_getattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) + 276: syscalls.ErrorWithEvent("renameat2", syserror.ENOSYS, "", []string{"gvisor.dev/issue/263"}), // TODO(b/118902772) + 277: syscalls.Supported("seccomp", Seccomp), + 278: syscalls.Supported("getrandom", GetRandom), + 279: syscalls.Supported("memfd_create", MemfdCreate), + 280: syscalls.CapError("bpf", linux.CAP_SYS_ADMIN, "", nil), + 281: syscalls.Supported("execveat", Execveat), + 282: syscalls.ErrorWithEvent("userfaultfd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/266"}), // TODO(b/118906345) + 283: syscalls.ErrorWithEvent("membarrier", syserror.ENOSYS, "", []string{"gvisor.dev/issue/267"}), // TODO(gvisor.dev/issue/267) + 284: syscalls.PartiallySupported("mlock2", Mlock2, "Stub implementation. The sandbox lacks appropriate permissions.", nil), + + // Syscalls after 284 are "backports" from versions of Linux after 4.4. + 285: syscalls.ErrorWithEvent("copy_file_range", syserror.ENOSYS, "", nil), + 286: syscalls.Supported("preadv2", Preadv2), + 287: syscalls.PartiallySupported("pwritev2", Pwritev2, "Flag RWF_HIPRI is not supported.", nil), + 288: syscalls.ErrorWithEvent("pkey_mprotect", syserror.ENOSYS, "", nil), + 289: syscalls.ErrorWithEvent("pkey_alloc", syserror.ENOSYS, "", nil), + 290: syscalls.ErrorWithEvent("pkey_free", syserror.ENOSYS, "", nil), + 291: syscalls.Supported("statx", Statx), + 292: syscalls.ErrorWithEvent("io_pgetevents", syserror.ENOSYS, "", nil), + 293: syscalls.PartiallySupported("rseq", RSeq, "Not supported on all platforms.", nil), + + // Linux skips ahead to syscall 424 to sync numbers between arches. + 424: syscalls.ErrorWithEvent("pidfd_send_signal", syserror.ENOSYS, "", nil), + 425: syscalls.ErrorWithEvent("io_uring_setup", syserror.ENOSYS, "", nil), + 426: syscalls.ErrorWithEvent("io_uring_enter", syserror.ENOSYS, "", nil), + 427: syscalls.ErrorWithEvent("io_uring_register", syserror.ENOSYS, "", nil), + 428: syscalls.ErrorWithEvent("open_tree", syserror.ENOSYS, "", nil), + 429: syscalls.ErrorWithEvent("move_mount", syserror.ENOSYS, "", nil), + 430: syscalls.ErrorWithEvent("fsopen", syserror.ENOSYS, "", nil), + 431: syscalls.ErrorWithEvent("fsconfig", syserror.ENOSYS, "", nil), + 432: syscalls.ErrorWithEvent("fsmount", syserror.ENOSYS, "", nil), + 433: syscalls.ErrorWithEvent("fspick", syserror.ENOSYS, "", nil), + 434: syscalls.ErrorWithEvent("pidfd_open", syserror.ENOSYS, "", nil), + 435: syscalls.ErrorWithEvent("clone3", syserror.ENOSYS, "", nil), + }, + Emulate: map[usermem.Addr]uintptr{}, + Missing: func(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, error) { + t.Kernel().EmitUnimplementedEvent(t) + return 0, syserror.ENOSYS + }, +} + +func init() { + kernel.RegisterSyscallTable(AMD64) + kernel.RegisterSyscallTable(ARM64) +} diff --git a/pkg/sentry/syscalls/linux/linux64_amd64.go b/pkg/sentry/syscalls/linux/linux64_amd64.go deleted file mode 100644 index 3021440ed..000000000 --- a/pkg/sentry/syscalls/linux/linux64_amd64.go +++ /dev/null @@ -1,386 +0,0 @@ -// Copyright 2018 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package linux - -import ( - "gvisor.dev/gvisor/pkg/abi" - "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/syscalls" - "gvisor.dev/gvisor/pkg/sentry/usermem" - "gvisor.dev/gvisor/pkg/syserror" -) - -// AMD64 is a table of Linux amd64 syscall API with the corresponding syscall -// numbers from Linux 4.4. -var AMD64 = &kernel.SyscallTable{ - OS: abi.Linux, - Arch: arch.AMD64, - Version: kernel.Version{ - // Version 4.4 is chosen as a stable, longterm version of Linux, which - // guides the interface provided by this syscall table. The build - // version is that for a clean build with default kernel config, at 5 - // minutes after v4.4 was tagged. - Sysname: LinuxSysname, - Release: LinuxRelease, - Version: LinuxVersion, - }, - AuditNumber: linux.AUDIT_ARCH_X86_64, - Table: map[uintptr]kernel.Syscall{ - 0: syscalls.Supported("read", Read), - 1: syscalls.Supported("write", Write), - 2: syscalls.PartiallySupported("open", Open, "Options O_DIRECT, O_NOATIME, O_PATH, O_TMPFILE, O_SYNC are not supported.", nil), - 3: syscalls.Supported("close", Close), - 4: syscalls.Supported("stat", Stat), - 5: syscalls.Supported("fstat", Fstat), - 6: syscalls.Supported("lstat", Lstat), - 7: syscalls.Supported("poll", Poll), - 8: syscalls.Supported("lseek", Lseek), - 9: syscalls.PartiallySupported("mmap", Mmap, "Generally supported with exceptions. Options MAP_FIXED_NOREPLACE, MAP_SHARED_VALIDATE, MAP_SYNC MAP_GROWSDOWN, MAP_HUGETLB are not supported.", nil), - 10: syscalls.Supported("mprotect", Mprotect), - 11: syscalls.Supported("munmap", Munmap), - 12: syscalls.Supported("brk", Brk), - 13: syscalls.Supported("rt_sigaction", RtSigaction), - 14: syscalls.Supported("rt_sigprocmask", RtSigprocmask), - 15: syscalls.Supported("rt_sigreturn", RtSigreturn), - 16: syscalls.PartiallySupported("ioctl", Ioctl, "Only a few ioctls are implemented for backing devices and file systems.", nil), - 17: syscalls.Supported("pread64", Pread64), - 18: syscalls.Supported("pwrite64", Pwrite64), - 19: syscalls.Supported("readv", Readv), - 20: syscalls.Supported("writev", Writev), - 21: syscalls.Supported("access", Access), - 22: syscalls.Supported("pipe", Pipe), - 23: syscalls.Supported("select", Select), - 24: syscalls.Supported("sched_yield", SchedYield), - 25: syscalls.Supported("mremap", Mremap), - 26: syscalls.PartiallySupported("msync", Msync, "Full data flush is not guaranteed at this time.", nil), - 27: syscalls.PartiallySupported("mincore", Mincore, "Stub implementation. The sandbox does not have access to this information. Reports all mapped pages are resident.", nil), - 28: syscalls.PartiallySupported("madvise", Madvise, "Options MADV_DONTNEED, MADV_DONTFORK are supported. Other advice is ignored.", nil), - 29: syscalls.PartiallySupported("shmget", Shmget, "Option SHM_HUGETLB is not supported.", nil), - 30: syscalls.PartiallySupported("shmat", Shmat, "Option SHM_RND is not supported.", nil), - 31: syscalls.PartiallySupported("shmctl", Shmctl, "Options SHM_LOCK, SHM_UNLOCK are not supported.", nil), - 32: syscalls.Supported("dup", Dup), - 33: syscalls.Supported("dup2", Dup2), - 34: syscalls.Supported("pause", Pause), - 35: syscalls.Supported("nanosleep", Nanosleep), - 36: syscalls.Supported("getitimer", Getitimer), - 37: syscalls.Supported("alarm", Alarm), - 38: syscalls.Supported("setitimer", Setitimer), - 39: syscalls.Supported("getpid", Getpid), - 40: syscalls.Supported("sendfile", Sendfile), - 41: syscalls.PartiallySupported("socket", Socket, "Limited support for AF_NETLINK, NETLINK_ROUTE sockets. Limited support for SOCK_RAW.", nil), - 42: syscalls.Supported("connect", Connect), - 43: syscalls.Supported("accept", Accept), - 44: syscalls.Supported("sendto", SendTo), - 45: syscalls.Supported("recvfrom", RecvFrom), - 46: syscalls.Supported("sendmsg", SendMsg), - 47: syscalls.PartiallySupported("recvmsg", RecvMsg, "Not all flags and control messages are supported.", nil), - 48: syscalls.PartiallySupported("shutdown", Shutdown, "Not all flags and control messages are supported.", nil), - 49: syscalls.PartiallySupported("bind", Bind, "Autobind for abstract Unix sockets is not supported.", nil), - 50: syscalls.Supported("listen", Listen), - 51: syscalls.Supported("getsockname", GetSockName), - 52: syscalls.Supported("getpeername", GetPeerName), - 53: syscalls.Supported("socketpair", SocketPair), - 54: syscalls.PartiallySupported("setsockopt", SetSockOpt, "Not all socket options are supported.", nil), - 55: syscalls.PartiallySupported("getsockopt", GetSockOpt, "Not all socket options are supported.", nil), - 56: syscalls.PartiallySupported("clone", Clone, "Mount namespace (CLONE_NEWNS) not supported. Options CLONE_PARENT, CLONE_SYSVSEM not supported.", nil), - 57: syscalls.Supported("fork", Fork), - 58: syscalls.Supported("vfork", Vfork), - 59: syscalls.Supported("execve", Execve), - 60: syscalls.Supported("exit", Exit), - 61: syscalls.Supported("wait4", Wait4), - 62: syscalls.Supported("kill", Kill), - 63: syscalls.Supported("uname", Uname), - 64: syscalls.Supported("semget", Semget), - 65: syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil), - 66: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, IPC_STAT, SEM_STAT, SEM_STAT_ANY, GETNCNT, GETZCNT not supported.", nil), - 67: syscalls.Supported("shmdt", Shmdt), - 68: syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 69: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 70: syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 71: syscalls.ErrorWithEvent("msgctl", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 72: syscalls.PartiallySupported("fcntl", Fcntl, "Not all options are supported.", nil), - 73: syscalls.PartiallySupported("flock", Flock, "Locks are held within the sandbox only.", nil), - 74: syscalls.PartiallySupported("fsync", Fsync, "Full data flush is not guaranteed at this time.", nil), - 75: syscalls.PartiallySupported("fdatasync", Fdatasync, "Full data flush is not guaranteed at this time.", nil), - 76: syscalls.Supported("truncate", Truncate), - 77: syscalls.Supported("ftruncate", Ftruncate), - 78: syscalls.Supported("getdents", Getdents), - 79: syscalls.Supported("getcwd", Getcwd), - 80: syscalls.Supported("chdir", Chdir), - 81: syscalls.Supported("fchdir", Fchdir), - 82: syscalls.Supported("rename", Rename), - 83: syscalls.Supported("mkdir", Mkdir), - 84: syscalls.Supported("rmdir", Rmdir), - 85: syscalls.Supported("creat", Creat), - 86: syscalls.Supported("link", Link), - 87: syscalls.Supported("unlink", Unlink), - 88: syscalls.Supported("symlink", Symlink), - 89: syscalls.Supported("readlink", Readlink), - 90: syscalls.Supported("chmod", Chmod), - 91: syscalls.PartiallySupported("fchmod", Fchmod, "Options S_ISUID and S_ISGID not supported.", nil), - 92: syscalls.Supported("chown", Chown), - 93: syscalls.Supported("fchown", Fchown), - 94: syscalls.Supported("lchown", Lchown), - 95: syscalls.Supported("umask", Umask), - 96: syscalls.Supported("gettimeofday", Gettimeofday), - 97: syscalls.Supported("getrlimit", Getrlimit), - 98: syscalls.PartiallySupported("getrusage", Getrusage, "Fields ru_maxrss, ru_minflt, ru_majflt, ru_inblock, ru_oublock are not supported. Fields ru_utime and ru_stime have low precision.", nil), - 99: syscalls.PartiallySupported("sysinfo", Sysinfo, "Fields loads, sharedram, bufferram, totalswap, freeswap, totalhigh, freehigh not supported.", nil), - 100: syscalls.Supported("times", Times), - 101: syscalls.PartiallySupported("ptrace", Ptrace, "Options PTRACE_PEEKSIGINFO, PTRACE_SECCOMP_GET_FILTER not supported.", nil), - 102: syscalls.Supported("getuid", Getuid), - 103: syscalls.PartiallySupported("syslog", Syslog, "Outputs a dummy message for security reasons.", nil), - 104: syscalls.Supported("getgid", Getgid), - 105: syscalls.Supported("setuid", Setuid), - 106: syscalls.Supported("setgid", Setgid), - 107: syscalls.Supported("geteuid", Geteuid), - 108: syscalls.Supported("getegid", Getegid), - 109: syscalls.Supported("setpgid", Setpgid), - 110: syscalls.Supported("getppid", Getppid), - 111: syscalls.Supported("getpgrp", Getpgrp), - 112: syscalls.Supported("setsid", Setsid), - 113: syscalls.Supported("setreuid", Setreuid), - 114: syscalls.Supported("setregid", Setregid), - 115: syscalls.Supported("getgroups", Getgroups), - 116: syscalls.Supported("setgroups", Setgroups), - 117: syscalls.Supported("setresuid", Setresuid), - 118: syscalls.Supported("getresuid", Getresuid), - 119: syscalls.Supported("setresgid", Setresgid), - 120: syscalls.Supported("getresgid", Getresgid), - 121: syscalls.Supported("getpgid", Getpgid), - 122: syscalls.ErrorWithEvent("setfsuid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) - 123: syscalls.ErrorWithEvent("setfsgid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) - 124: syscalls.Supported("getsid", Getsid), - 125: syscalls.Supported("capget", Capget), - 126: syscalls.Supported("capset", Capset), - 127: syscalls.Supported("rt_sigpending", RtSigpending), - 128: syscalls.Supported("rt_sigtimedwait", RtSigtimedwait), - 129: syscalls.Supported("rt_sigqueueinfo", RtSigqueueinfo), - 130: syscalls.Supported("rt_sigsuspend", RtSigsuspend), - 131: syscalls.Supported("sigaltstack", Sigaltstack), - 132: syscalls.Supported("utime", Utime), - 133: syscalls.PartiallySupported("mknod", Mknod, "Device creation is not generally supported. Only regular file and FIFO creation are supported.", nil), - 134: syscalls.Error("uselib", syserror.ENOSYS, "Obsolete", nil), - 135: syscalls.ErrorWithEvent("personality", syserror.EINVAL, "Unable to change personality.", nil), - 136: syscalls.ErrorWithEvent("ustat", syserror.ENOSYS, "Needs filesystem support.", nil), - 137: syscalls.PartiallySupported("statfs", Statfs, "Depends on the backing file system implementation.", nil), - 138: syscalls.PartiallySupported("fstatfs", Fstatfs, "Depends on the backing file system implementation.", nil), - 139: syscalls.ErrorWithEvent("sysfs", syserror.ENOSYS, "", []string{"gvisor.dev/issue/165"}), - 140: syscalls.PartiallySupported("getpriority", Getpriority, "Stub implementation.", nil), - 141: syscalls.PartiallySupported("setpriority", Setpriority, "Stub implementation.", nil), - 142: syscalls.CapError("sched_setparam", linux.CAP_SYS_NICE, "", nil), - 143: syscalls.PartiallySupported("sched_getparam", SchedGetparam, "Stub implementation.", nil), - 144: syscalls.PartiallySupported("sched_setscheduler", SchedSetscheduler, "Stub implementation.", nil), - 145: syscalls.PartiallySupported("sched_getscheduler", SchedGetscheduler, "Stub implementation.", nil), - 146: syscalls.PartiallySupported("sched_get_priority_max", SchedGetPriorityMax, "Stub implementation.", nil), - 147: syscalls.PartiallySupported("sched_get_priority_min", SchedGetPriorityMin, "Stub implementation.", nil), - 148: syscalls.ErrorWithEvent("sched_rr_get_interval", syserror.EPERM, "", nil), - 149: syscalls.PartiallySupported("mlock", Mlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 150: syscalls.PartiallySupported("munlock", Munlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 151: syscalls.PartiallySupported("mlockall", Mlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 152: syscalls.PartiallySupported("munlockall", Munlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 153: syscalls.CapError("vhangup", linux.CAP_SYS_TTY_CONFIG, "", nil), - 154: syscalls.Error("modify_ldt", syserror.EPERM, "", nil), - 155: syscalls.Error("pivot_root", syserror.EPERM, "", nil), - 156: syscalls.Error("sysctl", syserror.EPERM, "Deprecated. Use /proc/sys instead.", nil), - 157: syscalls.PartiallySupported("prctl", Prctl, "Not all options are supported.", nil), - 158: syscalls.PartiallySupported("arch_prctl", ArchPrctl, "Options ARCH_GET_GS, ARCH_SET_GS not supported.", nil), - 159: syscalls.CapError("adjtimex", linux.CAP_SYS_TIME, "", nil), - 160: syscalls.PartiallySupported("setrlimit", Setrlimit, "Not all rlimits are enforced.", nil), - 161: syscalls.Supported("chroot", Chroot), - 162: syscalls.PartiallySupported("sync", Sync, "Full data flush is not guaranteed at this time.", nil), - 163: syscalls.CapError("acct", linux.CAP_SYS_PACCT, "", nil), - 164: syscalls.CapError("settimeofday", linux.CAP_SYS_TIME, "", nil), - 165: syscalls.PartiallySupported("mount", Mount, "Not all options or file systems are supported.", nil), - 166: syscalls.PartiallySupported("umount2", Umount2, "Not all options or file systems are supported.", nil), - 167: syscalls.CapError("swapon", linux.CAP_SYS_ADMIN, "", nil), - 168: syscalls.CapError("swapoff", linux.CAP_SYS_ADMIN, "", nil), - 169: syscalls.CapError("reboot", linux.CAP_SYS_BOOT, "", nil), - 170: syscalls.Supported("sethostname", Sethostname), - 171: syscalls.Supported("setdomainname", Setdomainname), - 172: syscalls.CapError("iopl", linux.CAP_SYS_RAWIO, "", nil), - 173: syscalls.CapError("ioperm", linux.CAP_SYS_RAWIO, "", nil), - 174: syscalls.CapError("create_module", linux.CAP_SYS_MODULE, "", nil), - 175: syscalls.CapError("init_module", linux.CAP_SYS_MODULE, "", nil), - 176: syscalls.CapError("delete_module", linux.CAP_SYS_MODULE, "", nil), - 177: syscalls.Error("get_kernel_syms", syserror.ENOSYS, "Not supported in Linux > 2.6.", nil), - 178: syscalls.Error("query_module", syserror.ENOSYS, "Not supported in Linux > 2.6.", nil), - 179: syscalls.CapError("quotactl", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_admin for most operations - 180: syscalls.Error("nfsservctl", syserror.ENOSYS, "Removed after Linux 3.1.", nil), - 181: syscalls.Error("getpmsg", syserror.ENOSYS, "Not implemented in Linux.", nil), - 182: syscalls.Error("putpmsg", syserror.ENOSYS, "Not implemented in Linux.", nil), - 183: syscalls.Error("afs_syscall", syserror.ENOSYS, "Not implemented in Linux.", nil), - 184: syscalls.Error("tuxcall", syserror.ENOSYS, "Not implemented in Linux.", nil), - 185: syscalls.Error("security", syserror.ENOSYS, "Not implemented in Linux.", nil), - 186: syscalls.Supported("gettid", Gettid), - 187: syscalls.Supported("readahead", Readahead), - 188: syscalls.Error("setxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 189: syscalls.Error("lsetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 190: syscalls.Error("fsetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 191: syscalls.ErrorWithEvent("getxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 192: syscalls.ErrorWithEvent("lgetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 193: syscalls.ErrorWithEvent("fgetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 194: syscalls.ErrorWithEvent("listxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 195: syscalls.ErrorWithEvent("llistxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 196: syscalls.ErrorWithEvent("flistxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 197: syscalls.ErrorWithEvent("removexattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 198: syscalls.ErrorWithEvent("lremovexattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 199: syscalls.ErrorWithEvent("fremovexattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 200: syscalls.Supported("tkill", Tkill), - 201: syscalls.Supported("time", Time), - 202: syscalls.PartiallySupported("futex", Futex, "Robust futexes not supported.", nil), - 203: syscalls.PartiallySupported("sched_setaffinity", SchedSetaffinity, "Stub implementation.", nil), - 204: syscalls.PartiallySupported("sched_getaffinity", SchedGetaffinity, "Stub implementation.", nil), - 205: syscalls.Error("set_thread_area", syserror.ENOSYS, "Expected to return ENOSYS on 64-bit", nil), - 206: syscalls.PartiallySupported("io_setup", IoSetup, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 207: syscalls.PartiallySupported("io_destroy", IoDestroy, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 208: syscalls.PartiallySupported("io_getevents", IoGetevents, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 209: syscalls.PartiallySupported("io_submit", IoSubmit, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 210: syscalls.PartiallySupported("io_cancel", IoCancel, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 211: syscalls.Error("get_thread_area", syserror.ENOSYS, "Expected to return ENOSYS on 64-bit", nil), - 212: syscalls.CapError("lookup_dcookie", linux.CAP_SYS_ADMIN, "", nil), - 213: syscalls.Supported("epoll_create", EpollCreate), - 214: syscalls.ErrorWithEvent("epoll_ctl_old", syserror.ENOSYS, "Deprecated.", nil), - 215: syscalls.ErrorWithEvent("epoll_wait_old", syserror.ENOSYS, "Deprecated.", nil), - 216: syscalls.ErrorWithEvent("remap_file_pages", syserror.ENOSYS, "Deprecated since Linux 3.16.", nil), - 217: syscalls.Supported("getdents64", Getdents64), - 218: syscalls.Supported("set_tid_address", SetTidAddress), - 219: syscalls.Supported("restart_syscall", RestartSyscall), - 220: syscalls.ErrorWithEvent("semtimedop", syserror.ENOSYS, "", []string{"gvisor.dev/issue/137"}), // TODO(b/29354920) - 221: syscalls.PartiallySupported("fadvise64", Fadvise64, "Not all options are supported.", nil), - 222: syscalls.Supported("timer_create", TimerCreate), - 223: syscalls.Supported("timer_settime", TimerSettime), - 224: syscalls.Supported("timer_gettime", TimerGettime), - 225: syscalls.Supported("timer_getoverrun", TimerGetoverrun), - 226: syscalls.Supported("timer_delete", TimerDelete), - 227: syscalls.Supported("clock_settime", ClockSettime), - 228: syscalls.Supported("clock_gettime", ClockGettime), - 229: syscalls.Supported("clock_getres", ClockGetres), - 230: syscalls.Supported("clock_nanosleep", ClockNanosleep), - 231: syscalls.Supported("exit_group", ExitGroup), - 232: syscalls.Supported("epoll_wait", EpollWait), - 233: syscalls.Supported("epoll_ctl", EpollCtl), - 234: syscalls.Supported("tgkill", Tgkill), - 235: syscalls.Supported("utimes", Utimes), - 236: syscalls.Error("vserver", syserror.ENOSYS, "Not implemented by Linux", nil), - 237: syscalls.PartiallySupported("mbind", Mbind, "Stub implementation. Only a single NUMA node is advertised, and mempolicy is ignored accordingly, but mbind() will succeed and has effects reflected by get_mempolicy.", []string{"gvisor.dev/issue/262"}), - 238: syscalls.PartiallySupported("set_mempolicy", SetMempolicy, "Stub implementation.", nil), - 239: syscalls.PartiallySupported("get_mempolicy", GetMempolicy, "Stub implementation.", nil), - 240: syscalls.ErrorWithEvent("mq_open", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 241: syscalls.ErrorWithEvent("mq_unlink", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 242: syscalls.ErrorWithEvent("mq_timedsend", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 243: syscalls.ErrorWithEvent("mq_timedreceive", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 244: syscalls.ErrorWithEvent("mq_notify", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 245: syscalls.ErrorWithEvent("mq_getsetattr", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 246: syscalls.CapError("kexec_load", linux.CAP_SYS_BOOT, "", nil), - 247: syscalls.Supported("waitid", Waitid), - 248: syscalls.Error("add_key", syserror.EACCES, "Not available to user.", nil), - 249: syscalls.Error("request_key", syserror.EACCES, "Not available to user.", nil), - 250: syscalls.Error("keyctl", syserror.EACCES, "Not available to user.", nil), - 251: syscalls.CapError("ioprio_set", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) - 252: syscalls.CapError("ioprio_get", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) - 253: syscalls.PartiallySupported("inotify_init", InotifyInit, "inotify events are only available inside the sandbox.", nil), - 254: syscalls.PartiallySupported("inotify_add_watch", InotifyAddWatch, "inotify events are only available inside the sandbox.", nil), - 255: syscalls.PartiallySupported("inotify_rm_watch", InotifyRmWatch, "inotify events are only available inside the sandbox.", nil), - 256: syscalls.CapError("migrate_pages", linux.CAP_SYS_NICE, "", nil), - 257: syscalls.Supported("openat", Openat), - 258: syscalls.Supported("mkdirat", Mkdirat), - 259: syscalls.Supported("mknodat", Mknodat), - 260: syscalls.Supported("fchownat", Fchownat), - 261: syscalls.Supported("futimesat", Futimesat), - 262: syscalls.Supported("fstatat", Fstatat), - 263: syscalls.Supported("unlinkat", Unlinkat), - 264: syscalls.Supported("renameat", Renameat), - 265: syscalls.Supported("linkat", Linkat), - 266: syscalls.Supported("symlinkat", Symlinkat), - 267: syscalls.Supported("readlinkat", Readlinkat), - 268: syscalls.Supported("fchmodat", Fchmodat), - 269: syscalls.Supported("faccessat", Faccessat), - 270: syscalls.Supported("pselect", Pselect), - 271: syscalls.Supported("ppoll", Ppoll), - 272: syscalls.PartiallySupported("unshare", Unshare, "Mount, cgroup namespaces not supported. Network namespaces supported but must be empty.", nil), - 273: syscalls.Error("set_robust_list", syserror.ENOSYS, "Obsolete.", nil), - 274: syscalls.Error("get_robust_list", syserror.ENOSYS, "Obsolete.", nil), - 275: syscalls.Supported("splice", Splice), - 276: syscalls.Supported("tee", Tee), - 277: syscalls.PartiallySupported("sync_file_range", SyncFileRange, "Full data flush is not guaranteed at this time.", nil), - 278: syscalls.ErrorWithEvent("vmsplice", syserror.ENOSYS, "", []string{"gvisor.dev/issue/138"}), // TODO(b/29354098) - 279: syscalls.CapError("move_pages", linux.CAP_SYS_NICE, "", nil), // requires cap_sys_nice (mostly) - 280: syscalls.Supported("utimensat", Utimensat), - 281: syscalls.Supported("epoll_pwait", EpollPwait), - 282: syscalls.PartiallySupported("signalfd", Signalfd, "Semantics are slightly different.", []string{"gvisor.dev/issue/139"}), - 283: syscalls.Supported("timerfd_create", TimerfdCreate), - 284: syscalls.Supported("eventfd", Eventfd), - 285: syscalls.PartiallySupported("fallocate", Fallocate, "Not all options are supported.", nil), - 286: syscalls.Supported("timerfd_settime", TimerfdSettime), - 287: syscalls.Supported("timerfd_gettime", TimerfdGettime), - 288: syscalls.Supported("accept4", Accept4), - 289: syscalls.PartiallySupported("signalfd4", Signalfd4, "Semantics are slightly different.", []string{"gvisor.dev/issue/139"}), - 290: syscalls.Supported("eventfd2", Eventfd2), - 291: syscalls.Supported("epoll_create1", EpollCreate1), - 292: syscalls.Supported("dup3", Dup3), - 293: syscalls.Supported("pipe2", Pipe2), - 294: syscalls.Supported("inotify_init1", InotifyInit1), - 295: syscalls.Supported("preadv", Preadv), - 296: syscalls.Supported("pwritev", Pwritev), - 297: syscalls.Supported("rt_tgsigqueueinfo", RtTgsigqueueinfo), - 298: syscalls.ErrorWithEvent("perf_event_open", syserror.ENODEV, "No support for perf counters", nil), - 299: syscalls.PartiallySupported("recvmmsg", RecvMMsg, "Not all flags and control messages are supported.", nil), - 300: syscalls.ErrorWithEvent("fanotify_init", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), - 301: syscalls.ErrorWithEvent("fanotify_mark", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), - 302: syscalls.Supported("prlimit64", Prlimit64), - 303: syscalls.Error("name_to_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), - 304: syscalls.Error("open_by_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), - 305: syscalls.CapError("clock_adjtime", linux.CAP_SYS_TIME, "", nil), - 306: syscalls.PartiallySupported("syncfs", Syncfs, "Depends on backing file system.", nil), - 307: syscalls.PartiallySupported("sendmmsg", SendMMsg, "Not all flags and control messages are supported.", nil), - 308: syscalls.ErrorWithEvent("setns", syserror.EOPNOTSUPP, "Needs filesystem support", []string{"gvisor.dev/issue/140"}), // TODO(b/29354995) - 309: syscalls.Supported("getcpu", Getcpu), - 310: syscalls.ErrorWithEvent("process_vm_readv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), - 311: syscalls.ErrorWithEvent("process_vm_writev", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), - 312: syscalls.CapError("kcmp", linux.CAP_SYS_PTRACE, "", nil), - 313: syscalls.CapError("finit_module", linux.CAP_SYS_MODULE, "", nil), - 314: syscalls.ErrorWithEvent("sched_setattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) - 315: syscalls.ErrorWithEvent("sched_getattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) - 316: syscalls.ErrorWithEvent("renameat2", syserror.ENOSYS, "", []string{"gvisor.dev/issue/263"}), // TODO(b/118902772) - 317: syscalls.Supported("seccomp", Seccomp), - 318: syscalls.Supported("getrandom", GetRandom), - 319: syscalls.Supported("memfd_create", MemfdCreate), - 320: syscalls.CapError("kexec_file_load", linux.CAP_SYS_BOOT, "", nil), - 321: syscalls.CapError("bpf", linux.CAP_SYS_ADMIN, "", nil), - 322: syscalls.Supported("execveat", Execveat), - 323: syscalls.ErrorWithEvent("userfaultfd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/266"}), // TODO(b/118906345) - 324: syscalls.ErrorWithEvent("membarrier", syserror.ENOSYS, "", []string{"gvisor.dev/issue/267"}), // TODO(b/118904897) - 325: syscalls.PartiallySupported("mlock2", Mlock2, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - - // Syscalls after 325 are "backports" from versions of Linux after 4.4. - 326: syscalls.ErrorWithEvent("copy_file_range", syserror.ENOSYS, "", nil), - 327: syscalls.Supported("preadv2", Preadv2), - 328: syscalls.PartiallySupported("pwritev2", Pwritev2, "Flag RWF_HIPRI is not supported.", nil), - 332: syscalls.Supported("statx", Statx), - }, - - Emulate: map[usermem.Addr]uintptr{ - 0xffffffffff600000: 96, // vsyscall gettimeofday(2) - 0xffffffffff600400: 201, // vsyscall time(2) - 0xffffffffff600800: 309, // vsyscall getcpu(2) - }, - Missing: func(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, error) { - t.Kernel().EmitUnimplementedEvent(t) - return 0, syserror.ENOSYS - }, -} diff --git a/pkg/sentry/syscalls/linux/linux64_arm64.go b/pkg/sentry/syscalls/linux/linux64_arm64.go deleted file mode 100644 index 4cf7f836a..000000000 --- a/pkg/sentry/syscalls/linux/linux64_arm64.go +++ /dev/null @@ -1,313 +0,0 @@ -// Copyright 2019 The gVisor Authors. -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package linux - -import ( - "gvisor.dev/gvisor/pkg/abi" - "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/syscalls" - "gvisor.dev/gvisor/pkg/sentry/usermem" - "gvisor.dev/gvisor/pkg/syserror" -) - -// ARM64 is a table of Linux arm64 syscall API with the corresponding syscall -// numbers from Linux 4.4. -var ARM64 = &kernel.SyscallTable{ - OS: abi.Linux, - Arch: arch.ARM64, - Version: kernel.Version{ - Sysname: LinuxSysname, - Release: LinuxRelease, - Version: LinuxVersion, - }, - AuditNumber: linux.AUDIT_ARCH_AARCH64, - Table: map[uintptr]kernel.Syscall{ - 0: syscalls.PartiallySupported("io_setup", IoSetup, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 1: syscalls.PartiallySupported("io_destroy", IoDestroy, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 2: syscalls.PartiallySupported("io_submit", IoSubmit, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 3: syscalls.PartiallySupported("io_cancel", IoCancel, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 4: syscalls.PartiallySupported("io_getevents", IoGetevents, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}), - 5: syscalls.Error("setxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 6: syscalls.Error("lsetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 7: syscalls.Error("fsetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 8: syscalls.ErrorWithEvent("getxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 9: syscalls.ErrorWithEvent("lgetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 10: syscalls.ErrorWithEvent("fgetxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 11: syscalls.ErrorWithEvent("listxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 12: syscalls.ErrorWithEvent("llistxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 13: syscalls.ErrorWithEvent("flistxattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 14: syscalls.ErrorWithEvent("removexattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 15: syscalls.ErrorWithEvent("lremovexattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 16: syscalls.ErrorWithEvent("fremovexattr", syserror.ENOTSUP, "Requires filesystem support.", nil), - 17: syscalls.Supported("getcwd", Getcwd), - 18: syscalls.CapError("lookup_dcookie", linux.CAP_SYS_ADMIN, "", nil), - 19: syscalls.Supported("eventfd2", Eventfd2), - 20: syscalls.Supported("epoll_create1", EpollCreate1), - 21: syscalls.Supported("epoll_ctl", EpollCtl), - 22: syscalls.Supported("epoll_pwait", EpollPwait), - 23: syscalls.Supported("dup", Dup), - 24: syscalls.Supported("dup3", Dup3), - 26: syscalls.Supported("inotify_init1", InotifyInit1), - 27: syscalls.PartiallySupported("inotify_add_watch", InotifyAddWatch, "inotify events are only available inside the sandbox.", nil), - 28: syscalls.PartiallySupported("inotify_rm_watch", InotifyRmWatch, "inotify events are only available inside the sandbox.", nil), - 29: syscalls.PartiallySupported("ioctl", Ioctl, "Only a few ioctls are implemented for backing devices and file systems.", nil), - 30: syscalls.CapError("ioprio_set", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) - 31: syscalls.CapError("ioprio_get", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_nice or cap_sys_admin (depending) - 32: syscalls.PartiallySupported("flock", Flock, "Locks are held within the sandbox only.", nil), - 33: syscalls.Supported("mknodat", Mknodat), - 34: syscalls.Supported("mkdirat", Mkdirat), - 35: syscalls.Supported("unlinkat", Unlinkat), - 36: syscalls.Supported("symlinkat", Symlinkat), - 37: syscalls.Supported("linkat", Linkat), - 38: syscalls.Supported("renameat", Renameat), - 39: syscalls.PartiallySupported("umount2", Umount2, "Not all options or file systems are supported.", nil), - 40: syscalls.PartiallySupported("mount", Mount, "Not all options or file systems are supported.", nil), - 41: syscalls.Error("pivot_root", syserror.EPERM, "", nil), - 42: syscalls.Error("nfsservctl", syserror.ENOSYS, "Removed after Linux 3.1.", nil), - 44: syscalls.PartiallySupported("fstatfs", Fstatfs, "Depends on the backing file system implementation.", nil), - 46: syscalls.Supported("ftruncate", Ftruncate), - 47: syscalls.PartiallySupported("fallocate", Fallocate, "Not all options are supported.", nil), - 48: syscalls.Supported("faccessat", Faccessat), - 49: syscalls.Supported("chdir", Chdir), - 50: syscalls.Supported("fchdir", Fchdir), - 51: syscalls.Supported("chroot", Chroot), - 52: syscalls.PartiallySupported("fchmod", Fchmod, "Options S_ISUID and S_ISGID not supported.", nil), - 53: syscalls.Supported("fchmodat", Fchmodat), - 54: syscalls.Supported("fchownat", Fchownat), - 55: syscalls.Supported("fchown", Fchown), - 56: syscalls.Supported("openat", Openat), - 57: syscalls.Supported("close", Close), - 58: syscalls.CapError("vhangup", linux.CAP_SYS_TTY_CONFIG, "", nil), - 59: syscalls.Supported("pipe2", Pipe2), - 60: syscalls.CapError("quotactl", linux.CAP_SYS_ADMIN, "", nil), // requires cap_sys_admin for most operations - 61: syscalls.Supported("getdents64", Getdents64), - 62: syscalls.Supported("lseek", Lseek), - 63: syscalls.Supported("read", Read), - 64: syscalls.Supported("write", Write), - 65: syscalls.Supported("readv", Readv), - 66: syscalls.Supported("writev", Writev), - 67: syscalls.Supported("pread64", Pread64), - 68: syscalls.Supported("pwrite64", Pwrite64), - 69: syscalls.Supported("preadv", Preadv), - 70: syscalls.Supported("pwritev", Pwritev), - 71: syscalls.Supported("sendfile", Sendfile), - 72: syscalls.Supported("pselect", Pselect), - 73: syscalls.Supported("ppoll", Ppoll), - 74: syscalls.PartiallySupported("signalfd4", Signalfd4, "Semantics are slightly different.", []string{"gvisor.dev/issue/139"}), - 75: syscalls.ErrorWithEvent("vmsplice", syserror.ENOSYS, "", []string{"gvisor.dev/issue/138"}), // TODO(b/29354098) - 76: syscalls.PartiallySupported("splice", Splice, "Stub implementation.", []string{"gvisor.dev/issue/138"}), // TODO(b/29354098) - 77: syscalls.Supported("tee", Tee), - 78: syscalls.Supported("readlinkat", Readlinkat), - 80: syscalls.Supported("fstat", Fstat), - 81: syscalls.PartiallySupported("sync", Sync, "Full data flush is not guaranteed at this time.", nil), - 82: syscalls.PartiallySupported("fsync", Fsync, "Full data flush is not guaranteed at this time.", nil), - 83: syscalls.PartiallySupported("fdatasync", Fdatasync, "Full data flush is not guaranteed at this time.", nil), - 84: syscalls.PartiallySupported("sync_file_range", SyncFileRange, "Full data flush is not guaranteed at this time.", nil), - 85: syscalls.Supported("timerfd_create", TimerfdCreate), - 86: syscalls.Supported("timerfd_settime", TimerfdSettime), - 87: syscalls.Supported("timerfd_gettime", TimerfdGettime), - 88: syscalls.Supported("utimensat", Utimensat), - 89: syscalls.CapError("acct", linux.CAP_SYS_PACCT, "", nil), - 90: syscalls.Supported("capget", Capget), - 91: syscalls.Supported("capset", Capset), - 92: syscalls.ErrorWithEvent("personality", syserror.EINVAL, "Unable to change personality.", nil), - 93: syscalls.Supported("exit", Exit), - 94: syscalls.Supported("exit_group", ExitGroup), - 95: syscalls.Supported("waitid", Waitid), - 96: syscalls.Supported("set_tid_address", SetTidAddress), - 97: syscalls.PartiallySupported("unshare", Unshare, "Mount, cgroup namespaces not supported. Network namespaces supported but must be empty.", nil), - 98: syscalls.PartiallySupported("futex", Futex, "Robust futexes not supported.", nil), - 99: syscalls.Error("set_robust_list", syserror.ENOSYS, "Obsolete.", nil), - 100: syscalls.Error("get_robust_list", syserror.ENOSYS, "Obsolete.", nil), - 101: syscalls.Supported("nanosleep", Nanosleep), - 102: syscalls.Supported("getitimer", Getitimer), - 103: syscalls.Supported("setitimer", Setitimer), - 104: syscalls.CapError("kexec_load", linux.CAP_SYS_BOOT, "", nil), - 105: syscalls.CapError("init_module", linux.CAP_SYS_MODULE, "", nil), - 106: syscalls.CapError("delete_module", linux.CAP_SYS_MODULE, "", nil), - 107: syscalls.Supported("timer_create", TimerCreate), - 108: syscalls.Supported("timer_gettime", TimerGettime), - 109: syscalls.Supported("timer_getoverrun", TimerGetoverrun), - 110: syscalls.Supported("timer_settime", TimerSettime), - 111: syscalls.Supported("timer_delete", TimerDelete), - 112: syscalls.Supported("clock_settime", ClockSettime), - 113: syscalls.Supported("clock_gettime", ClockGettime), - 114: syscalls.Supported("clock_getres", ClockGetres), - 115: syscalls.Supported("clock_nanosleep", ClockNanosleep), - 116: syscalls.PartiallySupported("syslog", Syslog, "Outputs a dummy message for security reasons.", nil), - 117: syscalls.PartiallySupported("ptrace", Ptrace, "Options PTRACE_PEEKSIGINFO, PTRACE_SECCOMP_GET_FILTER not supported.", nil), - 118: syscalls.CapError("sched_setparam", linux.CAP_SYS_NICE, "", nil), - 119: syscalls.PartiallySupported("sched_setscheduler", SchedSetscheduler, "Stub implementation.", nil), - 120: syscalls.PartiallySupported("sched_getscheduler", SchedGetscheduler, "Stub implementation.", nil), - 121: syscalls.PartiallySupported("sched_getparam", SchedGetparam, "Stub implementation.", nil), - 122: syscalls.PartiallySupported("sched_setaffinity", SchedSetaffinity, "Stub implementation.", nil), - 123: syscalls.PartiallySupported("sched_getaffinity", SchedGetaffinity, "Stub implementation.", nil), - 124: syscalls.Supported("sched_yield", SchedYield), - 125: syscalls.PartiallySupported("sched_get_priority_max", SchedGetPriorityMax, "Stub implementation.", nil), - 126: syscalls.PartiallySupported("sched_get_priority_min", SchedGetPriorityMin, "Stub implementation.", nil), - 127: syscalls.ErrorWithEvent("sched_rr_get_interval", syserror.EPERM, "", nil), - 128: syscalls.Supported("restart_syscall", RestartSyscall), - 129: syscalls.Supported("kill", Kill), - 130: syscalls.Supported("tkill", Tkill), - 131: syscalls.Supported("tgkill", Tgkill), - 132: syscalls.Supported("sigaltstack", Sigaltstack), - 133: syscalls.Supported("rt_sigsuspend", RtSigsuspend), - 134: syscalls.Supported("rt_sigaction", RtSigaction), - 135: syscalls.Supported("rt_sigprocmask", RtSigprocmask), - 136: syscalls.Supported("rt_sigpending", RtSigpending), - 137: syscalls.Supported("rt_sigtimedwait", RtSigtimedwait), - 138: syscalls.Supported("rt_sigqueueinfo", RtSigqueueinfo), - 139: syscalls.Supported("rt_sigreturn", RtSigreturn), - 140: syscalls.PartiallySupported("setpriority", Setpriority, "Stub implementation.", nil), - 141: syscalls.PartiallySupported("getpriority", Getpriority, "Stub implementation.", nil), - 142: syscalls.CapError("reboot", linux.CAP_SYS_BOOT, "", nil), - 143: syscalls.Supported("setregid", Setregid), - 144: syscalls.Supported("setgid", Setgid), - 145: syscalls.Supported("setreuid", Setreuid), - 146: syscalls.Supported("setuid", Setuid), - 147: syscalls.Supported("setresuid", Setresuid), - 148: syscalls.Supported("getresuid", Getresuid), - 149: syscalls.Supported("setresgid", Setresgid), - 150: syscalls.Supported("getresgid", Getresgid), - 151: syscalls.ErrorWithEvent("setfsuid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) - 152: syscalls.ErrorWithEvent("setfsgid", syserror.ENOSYS, "", []string{"gvisor.dev/issue/260"}), // TODO(b/112851702) - 153: syscalls.Supported("times", Times), - 154: syscalls.Supported("setpgid", Setpgid), - 155: syscalls.Supported("getpgid", Getpgid), - 156: syscalls.Supported("getsid", Getsid), - 157: syscalls.Supported("setsid", Setsid), - 158: syscalls.Supported("getgroups", Getgroups), - 159: syscalls.Supported("setgroups", Setgroups), - 160: syscalls.Supported("uname", Uname), - 161: syscalls.Supported("sethostname", Sethostname), - 162: syscalls.Supported("setdomainname", Setdomainname), - 163: syscalls.Supported("getrlimit", Getrlimit), - 164: syscalls.PartiallySupported("setrlimit", Setrlimit, "Not all rlimits are enforced.", nil), - 165: syscalls.PartiallySupported("getrusage", Getrusage, "Fields ru_maxrss, ru_minflt, ru_majflt, ru_inblock, ru_oublock are not supported. Fields ru_utime and ru_stime have low precision.", nil), - 166: syscalls.Supported("umask", Umask), - 167: syscalls.PartiallySupported("prctl", Prctl, "Not all options are supported.", nil), - 168: syscalls.Supported("getcpu", Getcpu), - 169: syscalls.Supported("gettimeofday", Gettimeofday), - 170: syscalls.CapError("settimeofday", linux.CAP_SYS_TIME, "", nil), - 171: syscalls.CapError("adjtimex", linux.CAP_SYS_TIME, "", nil), - 172: syscalls.Supported("getpid", Getpid), - 173: syscalls.Supported("getppid", Getppid), - 174: syscalls.Supported("getuid", Getuid), - 175: syscalls.Supported("geteuid", Geteuid), - 176: syscalls.Supported("getgid", Getgid), - 177: syscalls.Supported("getegid", Getegid), - 178: syscalls.Supported("gettid", Gettid), - 179: syscalls.PartiallySupported("sysinfo", Sysinfo, "Fields loads, sharedram, bufferram, totalswap, freeswap, totalhigh, freehigh not supported.", nil), - 180: syscalls.ErrorWithEvent("mq_open", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 181: syscalls.ErrorWithEvent("mq_unlink", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 182: syscalls.ErrorWithEvent("mq_timedsend", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 183: syscalls.ErrorWithEvent("mq_timedreceive", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 184: syscalls.ErrorWithEvent("mq_notify", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 185: syscalls.ErrorWithEvent("mq_getsetattr", syserror.ENOSYS, "", []string{"gvisor.dev/issue/136"}), // TODO(b/29354921) - 186: syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 187: syscalls.ErrorWithEvent("msgctl", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 188: syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 189: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) - 190: syscalls.Supported("semget", Semget), - 191: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, IPC_STAT, SEM_STAT, SEM_STAT_ANY, GETNCNT, GETZCNT not supported.", nil), - 192: syscalls.ErrorWithEvent("semtimedop", syserror.ENOSYS, "", []string{"gvisor.dev/issue/137"}), // TODO(b/29354920) - 193: syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil), - 194: syscalls.PartiallySupported("shmget", Shmget, "Option SHM_HUGETLB is not supported.", nil), - 195: syscalls.PartiallySupported("shmctl", Shmctl, "Options SHM_LOCK, SHM_UNLOCK are not supported.", nil), - 196: syscalls.PartiallySupported("shmat", Shmat, "Option SHM_RND is not supported.", nil), - 197: syscalls.Supported("shmdt", Shmdt), - 198: syscalls.PartiallySupported("socket", Socket, "Limited support for AF_NETLINK, NETLINK_ROUTE sockets. Limited support for SOCK_RAW.", nil), - 199: syscalls.Supported("socketpair", SocketPair), - 200: syscalls.PartiallySupported("bind", Bind, "Autobind for abstract Unix sockets is not supported.", nil), - 201: syscalls.Supported("listen", Listen), - 202: syscalls.Supported("accept", Accept), - 203: syscalls.Supported("connect", Connect), - 204: syscalls.Supported("getsockname", GetSockName), - 205: syscalls.Supported("getpeername", GetPeerName), - 206: syscalls.Supported("sendto", SendTo), - 207: syscalls.Supported("recvfrom", RecvFrom), - 208: syscalls.PartiallySupported("setsockopt", SetSockOpt, "Not all socket options are supported.", nil), - 209: syscalls.PartiallySupported("getsockopt", GetSockOpt, "Not all socket options are supported.", nil), - 210: syscalls.PartiallySupported("shutdown", Shutdown, "Not all flags and control messages are supported.", nil), - 211: syscalls.Supported("sendmsg", SendMsg), - 212: syscalls.PartiallySupported("recvmsg", RecvMsg, "Not all flags and control messages are supported.", nil), - 213: syscalls.Supported("readahead", Readahead), - 214: syscalls.Supported("brk", Brk), - 215: syscalls.Supported("munmap", Munmap), - 216: syscalls.Supported("mremap", Mremap), - 217: syscalls.Error("add_key", syserror.EACCES, "Not available to user.", nil), - 218: syscalls.Error("request_key", syserror.EACCES, "Not available to user.", nil), - 219: syscalls.Error("keyctl", syserror.EACCES, "Not available to user.", nil), - 220: syscalls.PartiallySupported("clone", Clone, "Mount namespace (CLONE_NEWNS) not supported. Options CLONE_PARENT, CLONE_SYSVSEM not supported.", nil), - 221: syscalls.Supported("execve", Execve), - 224: syscalls.CapError("swapon", linux.CAP_SYS_ADMIN, "", nil), - 225: syscalls.CapError("swapoff", linux.CAP_SYS_ADMIN, "", nil), - 226: syscalls.Supported("mprotect", Mprotect), - 227: syscalls.PartiallySupported("msync", Msync, "Full data flush is not guaranteed at this time.", nil), - 228: syscalls.PartiallySupported("mlock", Mlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 229: syscalls.PartiallySupported("munlock", Munlock, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 230: syscalls.PartiallySupported("mlockall", Mlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 231: syscalls.PartiallySupported("munlockall", Munlockall, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 232: syscalls.PartiallySupported("mincore", Mincore, "Stub implementation. The sandbox does not have access to this information. Reports all mapped pages are resident.", nil), - 233: syscalls.PartiallySupported("madvise", Madvise, "Options MADV_DONTNEED, MADV_DONTFORK are supported. Other advice is ignored.", nil), - 234: syscalls.ErrorWithEvent("remap_file_pages", syserror.ENOSYS, "Deprecated since Linux 3.16.", nil), - 235: syscalls.PartiallySupported("mbind", Mbind, "Stub implementation. Only a single NUMA node is advertised, and mempolicy is ignored accordingly, but mbind() will succeed and has effects reflected by get_mempolicy.", []string{"gvisor.dev/issue/262"}), - 236: syscalls.PartiallySupported("get_mempolicy", GetMempolicy, "Stub implementation.", nil), - 237: syscalls.PartiallySupported("set_mempolicy", SetMempolicy, "Stub implementation.", nil), - 238: syscalls.CapError("migrate_pages", linux.CAP_SYS_NICE, "", nil), - 239: syscalls.CapError("move_pages", linux.CAP_SYS_NICE, "", nil), // requires cap_sys_nice (mostly) - 240: syscalls.Supported("rt_tgsigqueueinfo", RtTgsigqueueinfo), - 241: syscalls.ErrorWithEvent("perf_event_open", syserror.ENODEV, "No support for perf counters", nil), - 242: syscalls.Supported("accept4", Accept4), - 243: syscalls.PartiallySupported("recvmmsg", RecvMMsg, "Not all flags and control messages are supported.", nil), - 260: syscalls.Supported("wait4", Wait4), - 261: syscalls.Supported("prlimit64", Prlimit64), - 262: syscalls.ErrorWithEvent("fanotify_init", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), - 263: syscalls.ErrorWithEvent("fanotify_mark", syserror.ENOSYS, "Needs CONFIG_FANOTIFY", nil), - 264: syscalls.Error("name_to_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), - 265: syscalls.Error("open_by_handle_at", syserror.EOPNOTSUPP, "Not supported by gVisor filesystems", nil), - 266: syscalls.CapError("clock_adjtime", linux.CAP_SYS_TIME, "", nil), - 267: syscalls.PartiallySupported("syncfs", Syncfs, "Depends on backing file system.", nil), - 268: syscalls.ErrorWithEvent("setns", syserror.EOPNOTSUPP, "Needs filesystem support", []string{"gvisor.dev/issue/140"}), // TODO(b/29354995) - 269: syscalls.PartiallySupported("sendmmsg", SendMMsg, "Not all flags and control messages are supported.", nil), - 270: syscalls.ErrorWithEvent("process_vm_readv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), - 271: syscalls.ErrorWithEvent("process_vm_writev", syserror.ENOSYS, "", []string{"gvisor.dev/issue/158"}), - 272: syscalls.CapError("kcmp", linux.CAP_SYS_PTRACE, "", nil), - 273: syscalls.CapError("finit_module", linux.CAP_SYS_MODULE, "", nil), - 274: syscalls.ErrorWithEvent("sched_setattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) - 275: syscalls.ErrorWithEvent("sched_getattr", syserror.ENOSYS, "gVisor does not implement a scheduler.", []string{"gvisor.dev/issue/264"}), // TODO(b/118902272) - 276: syscalls.ErrorWithEvent("renameat2", syserror.ENOSYS, "", []string{"gvisor.dev/issue/263"}), // TODO(b/118902772) - 277: syscalls.Supported("seccomp", Seccomp), - 278: syscalls.Supported("getrandom", GetRandom), - 279: syscalls.Supported("memfd_create", MemfdCreate), - 280: syscalls.CapError("bpf", linux.CAP_SYS_ADMIN, "", nil), - 281: syscalls.ErrorWithEvent("execveat", syserror.ENOSYS, "", []string{"gvisor.dev/issue/265"}), // TODO(b/118901836) - 282: syscalls.ErrorWithEvent("userfaultfd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/266"}), // TODO(b/118906345) - 283: syscalls.ErrorWithEvent("membarrier", syserror.ENOSYS, "", []string{"gvisor.dev/issue/267"}), // TODO(b/118904897) - 284: syscalls.PartiallySupported("mlock2", Mlock2, "Stub implementation. The sandbox lacks appropriate permissions.", nil), - 285: syscalls.ErrorWithEvent("copy_file_range", syserror.ENOSYS, "", nil), - 286: syscalls.Supported("preadv2", Preadv2), - 287: syscalls.PartiallySupported("pwritev2", Pwritev2, "Flag RWF_HIPRI is not supported.", nil), - 291: syscalls.Supported("statx", Statx), - }, - Emulate: map[usermem.Addr]uintptr{}, - - Missing: func(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, error) { - t.Kernel().EmitUnimplementedEvent(t) - return 0, syserror.ENOSYS - }, -} diff --git a/pkg/sentry/syscalls/linux/sigset.go b/pkg/sentry/syscalls/linux/sigset.go index 333013d8c..434559b80 100644 --- a/pkg/sentry/syscalls/linux/sigset.go +++ b/pkg/sentry/syscalls/linux/sigset.go @@ -17,13 +17,17 @@ package linux import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) -// copyInSigSet copies in a sigset_t, checks its size, and ensures that KILL and +// CopyInSigSet copies in a sigset_t, checks its size, and ensures that KILL and // STOP are clear. -func copyInSigSet(t *kernel.Task, sigSetAddr usermem.Addr, size uint) (linux.SignalSet, error) { +// +// TODO(gvisor.dev/issue/1624): This is only exported because +// syscalls/vfs2/signal.go depends on it. Once vfs1 is deleted and the vfs2 +// syscalls are moved into this package, then they can be unexported. +func CopyInSigSet(t *kernel.Task, sigSetAddr usermem.Addr, size uint) (linux.SignalSet, error) { if size != linux.SignalSetSize { return 0, syserror.EINVAL } diff --git a/pkg/sentry/syscalls/linux/sys_aio.go b/pkg/sentry/syscalls/linux/sys_aio.go index f56411bfe..e9d64dec5 100644 --- a/pkg/sentry/syscalls/linux/sys_aio.go +++ b/pkg/sentry/syscalls/linux/sys_aio.go @@ -15,71 +15,18 @@ package linux import ( - "encoding/binary" - + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/eventfd" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) -// I/O commands. -const ( - _IOCB_CMD_PREAD = 0 - _IOCB_CMD_PWRITE = 1 - _IOCB_CMD_FSYNC = 2 - _IOCB_CMD_FDSYNC = 3 - _IOCB_CMD_NOOP = 6 - _IOCB_CMD_PREADV = 7 - _IOCB_CMD_PWRITEV = 8 -) - -// I/O flags. -const ( - _IOCB_FLAG_RESFD = 1 -) - -// ioCallback describes an I/O request. -// -// The priority field is currently ignored in the implementation below. Also -// note that the IOCB_FLAG_RESFD feature is not supported. -type ioCallback struct { - Data uint64 - Key uint32 - Reserved1 uint32 - - OpCode uint16 - ReqPrio int16 - FD int32 - - Buf uint64 - Bytes uint64 - Offset int64 - - Reserved2 uint64 - Flags uint32 - - // eventfd to signal if IOCB_FLAG_RESFD is set in flags. - ResFD int32 -} - -// ioEvent describes an I/O result. -// -// +stateify savable -type ioEvent struct { - Data uint64 - Obj uint64 - Result int64 - Result2 int64 -} - -// ioEventSize is the size of an ioEvent encoded. -var ioEventSize = binary.Size(ioEvent{}) - // IoSetup implements linux syscall io_setup(2). func IoSetup(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { nrEvents := args[0].Int() @@ -114,14 +61,28 @@ func IoSetup(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca func IoDestroy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { id := args[0].Uint64() - // Destroy the given context. - if !t.MemoryManager().DestroyAIOContext(t, id) { + ctx := t.MemoryManager().DestroyAIOContext(t, id) + if ctx == nil { // Does not exist. return 0, nil, syserror.EINVAL } - // FIXME(fvoznika): Linux blocks until all AIO to the destroyed context is - // done. - return 0, nil, nil + + // Drain completed requests amd wait for pending requests until there are no + // more. + for { + ctx.Drain() + + ch := ctx.WaitChannel() + if ch == nil { + // No more requests, we're done. + return 0, nil, nil + } + // The task cannot be interrupted during the wait. Equivalent to + // TASK_UNINTERRUPTIBLE in Linux. + t.UninterruptibleSleepStart(true /* deactivate */) + <-ch + t.UninterruptibleSleepFinish(true /* activate */) + } } // IoGetevents implements linux syscall io_getevents(2). @@ -178,7 +139,7 @@ func IoGetevents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S } } - ev := v.(*ioEvent) + ev := v.(*linux.IOEvent) // Copy out the result. if _, err := t.CopyOut(eventsAddr, ev); err != nil { @@ -190,7 +151,7 @@ func IoGetevents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S } // Keep rolling. - eventsAddr += usermem.Addr(ioEventSize) + eventsAddr += usermem.Addr(linux.IOEventSize) } // Everything finished. @@ -200,13 +161,13 @@ func IoGetevents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S func waitForRequest(ctx *mm.AIOContext, t *kernel.Task, haveDeadline bool, deadline ktime.Time) (interface{}, error) { for { if v, ok := ctx.PopRequest(); ok { - // Request was readly available. Just return it. + // Request was readily available. Just return it. return v, nil } // Need to wait for request completion. - done, active := ctx.WaitChannel() - if !active { + done := ctx.WaitChannel() + if done == nil { // Context has been destroyed. return nil, syserror.EINVAL } @@ -217,7 +178,7 @@ func waitForRequest(ctx *mm.AIOContext, t *kernel.Task, haveDeadline bool, deadl } // memoryFor returns appropriate memory for the given callback. -func memoryFor(t *kernel.Task, cb *ioCallback) (usermem.IOSequence, error) { +func memoryFor(t *kernel.Task, cb *linux.IOCallback) (usermem.IOSequence, error) { bytes := int(cb.Bytes) if bytes < 0 { // Linux also requires that this field fit in ssize_t. @@ -228,17 +189,17 @@ func memoryFor(t *kernel.Task, cb *ioCallback) (usermem.IOSequence, error) { // we have no guarantee that t's AddressSpace will be active during the // I/O. switch cb.OpCode { - case _IOCB_CMD_PREAD, _IOCB_CMD_PWRITE: + case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PWRITE: return t.SingleIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{ AddressSpaceActive: false, }) - case _IOCB_CMD_PREADV, _IOCB_CMD_PWRITEV: + case linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITEV: return t.IovecsIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{ AddressSpaceActive: false, }) - case _IOCB_CMD_FSYNC, _IOCB_CMD_FDSYNC, _IOCB_CMD_NOOP: + case linux.IOCB_CMD_FSYNC, linux.IOCB_CMD_FDSYNC, linux.IOCB_CMD_NOOP: return usermem.IOSequence{}, nil default: @@ -247,66 +208,78 @@ func memoryFor(t *kernel.Task, cb *ioCallback) (usermem.IOSequence, error) { } } -func performCallback(t *kernel.Task, file *fs.File, cbAddr usermem.Addr, cb *ioCallback, ioseq usermem.IOSequence, ctx *mm.AIOContext, eventFile *fs.File) { - ev := &ioEvent{ - Data: cb.Data, - Obj: uint64(cbAddr), - } +// IoCancel implements linux syscall io_cancel(2). +// +// It is not presently supported (ENOSYS indicates no support on this +// architecture). +func IoCancel(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, syserror.ENOSYS +} - // Construct a context.Context that will not be interrupted if t is - // interrupted. - c := t.AsyncContext() +// LINT.IfChange - var err error - switch cb.OpCode { - case _IOCB_CMD_PREAD, _IOCB_CMD_PREADV: - ev.Result, err = file.Preadv(c, ioseq, cb.Offset) - case _IOCB_CMD_PWRITE, _IOCB_CMD_PWRITEV: - ev.Result, err = file.Pwritev(c, ioseq, cb.Offset) - case _IOCB_CMD_FSYNC: - err = file.Fsync(c, 0, fs.FileMaxOffset, fs.SyncAll) - case _IOCB_CMD_FDSYNC: - err = file.Fsync(c, 0, fs.FileMaxOffset, fs.SyncData) - } +func getAIOCallback(t *kernel.Task, file *fs.File, cbAddr usermem.Addr, cb *linux.IOCallback, ioseq usermem.IOSequence, actx *mm.AIOContext, eventFile *fs.File) kernel.AIOCallback { + return func(ctx context.Context) { + if actx.Dead() { + actx.CancelPendingRequest() + return + } + ev := &linux.IOEvent{ + Data: cb.Data, + Obj: uint64(cbAddr), + } - // Update the result. - if err != nil { - err = handleIOError(t, ev.Result != 0 /* partial */, err, nil /* never interrupted */, "aio", file) - ev.Result = -int64(t.ExtractErrno(err, 0)) - } + var err error + switch cb.OpCode { + case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV: + ev.Result, err = file.Preadv(ctx, ioseq, cb.Offset) + case linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV: + ev.Result, err = file.Pwritev(ctx, ioseq, cb.Offset) + case linux.IOCB_CMD_FSYNC: + err = file.Fsync(ctx, 0, fs.FileMaxOffset, fs.SyncAll) + case linux.IOCB_CMD_FDSYNC: + err = file.Fsync(ctx, 0, fs.FileMaxOffset, fs.SyncData) + } + + // Update the result. + if err != nil { + err = handleIOError(t, ev.Result != 0 /* partial */, err, nil /* never interrupted */, "aio", file) + ev.Result = -int64(kernel.ExtractErrno(err, 0)) + } - file.DecRef() + file.DecRef(ctx) - // Queue the result for delivery. - ctx.FinishRequest(ev) + // Queue the result for delivery. + actx.FinishRequest(ev) - // Notify the event file if one was specified. This needs to happen - // *after* queueing the result to avoid racing with the thread we may - // wake up. - if eventFile != nil { - eventFile.FileOperations.(*eventfd.EventOperations).Signal(1) - eventFile.DecRef() + // Notify the event file if one was specified. This needs to happen + // *after* queueing the result to avoid racing with the thread we may + // wake up. + if eventFile != nil { + eventFile.FileOperations.(*eventfd.EventOperations).Signal(1) + eventFile.DecRef(ctx) + } } } // submitCallback processes a single callback. -func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Addr) error { +func submitCallback(t *kernel.Task, id uint64, cb *linux.IOCallback, cbAddr usermem.Addr) error { file := t.GetFile(cb.FD) if file == nil { // File not found. return syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Was there an eventFD? Extract it. var eventFile *fs.File - if cb.Flags&_IOCB_FLAG_RESFD != 0 { + if cb.Flags&linux.IOCB_FLAG_RESFD != 0 { eventFile = t.GetFile(cb.ResFD) if eventFile == nil { // Bad FD. return syserror.EBADF } - defer eventFile.DecRef() + defer eventFile.DecRef(t) // Check that it is an eventfd. if _, ok := eventFile.FileOperations.(*eventfd.EventOperations); !ok { @@ -322,7 +295,7 @@ func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Ad // Check offset for reads/writes. switch cb.OpCode { - case _IOCB_CMD_PREAD, _IOCB_CMD_PREADV, _IOCB_CMD_PWRITE, _IOCB_CMD_PWRITEV: + case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV: if cb.Offset < 0 { return syserror.EINVAL } @@ -348,7 +321,7 @@ func submitCallback(t *kernel.Task, id uint64, cb *ioCallback, cbAddr usermem.Ad // Perform the request asynchronously. file.IncRef() - fs.Async(func() { performCallback(t, file, cbAddr, cb, ioseq, ctx, eventFile) }) + t.QueueAIO(getAIOCallback(t, file, cbAddr, cb, ioseq, ctx, eventFile)) // All set. return nil @@ -377,7 +350,7 @@ func IoSubmit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc } // Copy in this callback. - var cb ioCallback + var cb linux.IOCallback cbAddr := usermem.Addr(t.Arch().Value(cbAddrNative)) if _, err := t.CopyIn(cbAddr, &cb); err != nil { @@ -406,10 +379,4 @@ func IoSubmit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc return uintptr(nrEvents), nil, nil } -// IoCancel implements linux syscall io_cancel(2). -// -// It is not presently supported (ENOSYS indicates no support on this -// architecture). -func IoCancel(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - return 0, nil, syserror.ENOSYS -} +// LINT.ThenChange(vfs2/aio.go) diff --git a/pkg/sentry/syscalls/linux/sys_clone_amd64.go b/pkg/sentry/syscalls/linux/sys_clone_amd64.go new file mode 100644 index 000000000..dd43cf18d --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_clone_amd64.go @@ -0,0 +1,35 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build amd64 + +package linux + +import ( + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" +) + +// Clone implements linux syscall clone(2). +// sys_clone has so many flavors. We implement the default one in linux 3.11 +// x86_64: +// sys_clone(clone_flags, newsp, parent_tidptr, child_tidptr, tls_val) +func Clone(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + flags := int(args[0].Int()) + stack := args[1].Pointer() + parentTID := args[2].Pointer() + childTID := args[3].Pointer() + tls := args[4].Pointer() + return clone(t, flags, stack, parentTID, childTID, tls) +} diff --git a/pkg/sentry/syscalls/linux/sys_clone_arm64.go b/pkg/sentry/syscalls/linux/sys_clone_arm64.go new file mode 100644 index 000000000..cf68a8949 --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_clone_arm64.go @@ -0,0 +1,35 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build arm64 + +package linux + +import ( + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" +) + +// Clone implements linux syscall clone(2). +// sys_clone has so many flavors, and we implement the default one in linux 3.11 +// arm64(kernel/fork.c with CONFIG_CLONE_BACKWARDS defined in the config file): +// sys_clone(clone_flags, newsp, parent_tidptr, tls_val, child_tidptr) +func Clone(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + flags := int(args[0].Int()) + stack := args[1].Pointer() + parentTID := args[2].Pointer() + tls := args[3].Pointer() + childTID := args[4].Pointer() + return clone(t, flags, stack, parentTID, childTID, tls) +} diff --git a/pkg/sentry/syscalls/linux/sys_epoll.go b/pkg/sentry/syscalls/linux/sys_epoll.go index 65b4a227b..7f460d30b 100644 --- a/pkg/sentry/syscalls/linux/sys_epoll.go +++ b/pkg/sentry/syscalls/linux/sys_epoll.go @@ -20,11 +20,12 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/epoll" "gvisor.dev/gvisor/pkg/sentry/syscalls" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" "gvisor.dev/gvisor/pkg/waiter" ) +// LINT.IfChange + // EpollCreate1 implements the epoll_create1(2) linux syscall. func EpollCreate1(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { flags := args[0].Int() @@ -70,7 +71,7 @@ func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc var data [2]int32 if op != linux.EPOLL_CTL_DEL { var e linux.EpollEvent - if _, err := t.CopyIn(eventAddr, &e); err != nil { + if _, err := e.CopyIn(t, eventAddr); err != nil { return 0, nil, err } @@ -83,8 +84,7 @@ func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc } mask = waiter.EventMaskFromLinux(e.Events) - data[0] = e.Fd - data[1] = e.Data + data = e.Data } // Perform the requested operations. @@ -104,28 +104,6 @@ func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc } } -// copyOutEvents copies epoll events from the kernel to user memory. -func copyOutEvents(t *kernel.Task, addr usermem.Addr, e []epoll.Event) error { - const itemLen = 12 - buffLen := len(e) * itemLen - if _, ok := addr.AddLength(uint64(buffLen)); !ok { - return syserror.EFAULT - } - - b := t.CopyScratchBuffer(buffLen) - for i := range e { - usermem.ByteOrder.PutUint32(b[i*itemLen:], e[i].Events) - usermem.ByteOrder.PutUint32(b[i*itemLen+4:], uint32(e[i].Data[0])) - usermem.ByteOrder.PutUint32(b[i*itemLen+8:], uint32(e[i].Data[1])) - } - - if _, err := t.CopyOutBytes(addr, b); err != nil { - return err - } - - return nil -} - // EpollWait implements the epoll_wait(2) linux syscall. func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { epfd := args[0].Int() @@ -139,7 +117,7 @@ func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys } if len(r) != 0 { - if err := copyOutEvents(t, eventsAddr, r); err != nil { + if _, err := linux.CopyEpollEventSliceOut(t, eventsAddr, r); err != nil { return 0, nil, err } } @@ -153,7 +131,7 @@ func EpollPwait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy maskSize := uint(args[5].Uint()) if maskAddr != 0 { - mask, err := copyInSigSet(t, maskAddr, maskSize) + mask, err := CopyInSigSet(t, maskAddr, maskSize) if err != nil { return 0, nil, err } @@ -165,3 +143,5 @@ func EpollPwait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy return EpollWait(t, args) } + +// LINT.ThenChange(vfs2/epoll.go) diff --git a/pkg/sentry/syscalls/linux/sys_eventfd.go b/pkg/sentry/syscalls/linux/sys_eventfd.go index 8a34c4e99..3b4f879e4 100644 --- a/pkg/sentry/syscalls/linux/sys_eventfd.go +++ b/pkg/sentry/syscalls/linux/sys_eventfd.go @@ -15,6 +15,7 @@ package linux import ( + "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" @@ -22,32 +23,24 @@ import ( "gvisor.dev/gvisor/pkg/syserror" ) -const ( - // EFD_SEMAPHORE is a flag used in syscall eventfd(2) and eventfd2(2). Please - // see its man page for more information. - EFD_SEMAPHORE = 1 - EFD_NONBLOCK = 0x800 - EFD_CLOEXEC = 0x80000 -) - // Eventfd2 implements linux syscall eventfd2(2). func Eventfd2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { initVal := args[0].Int() flags := uint(args[1].Uint()) - allOps := uint(EFD_SEMAPHORE | EFD_NONBLOCK | EFD_CLOEXEC) + allOps := uint(linux.EFD_SEMAPHORE | linux.EFD_NONBLOCK | linux.EFD_CLOEXEC) if flags & ^allOps != 0 { return 0, nil, syserror.EINVAL } - event := eventfd.New(t, uint64(initVal), flags&EFD_SEMAPHORE != 0) + event := eventfd.New(t, uint64(initVal), flags&linux.EFD_SEMAPHORE != 0) event.SetFlags(fs.SettableFileFlags{ - NonBlocking: flags&EFD_NONBLOCK != 0, + NonBlocking: flags&linux.EFD_NONBLOCK != 0, }) - defer event.DecRef() + defer event.DecRef(t) fd, err := t.NewFDFrom(0, event, kernel.FDFlags{ - CloseOnExec: flags&EFD_CLOEXEC != 0, + CloseOnExec: flags&linux.EFD_CLOEXEC != 0, }) if err != nil { return 0, nil, err diff --git a/pkg/sentry/syscalls/linux/sys_file.go b/pkg/sentry/syscalls/linux/sys_file.go index b9a8e3e21..1bc9b184e 100644 --- a/pkg/sentry/syscalls/linux/sys_file.go +++ b/pkg/sentry/syscalls/linux/sys_file.go @@ -18,8 +18,8 @@ import ( "syscall" "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" "gvisor.dev/gvisor/pkg/sentry/arch" - "gvisor.dev/gvisor/pkg/sentry/context" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/fs/lock" "gvisor.dev/gvisor/pkg/sentry/fs/tmpfs" @@ -28,8 +28,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel/fasync" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // fileOpAt performs an operation on the second last component in the path. @@ -40,7 +40,7 @@ func fileOpAt(t *kernel.Task, dirFD int32, path string, fn func(root *fs.Dirent, // Common case: we are accessing a file in the root. root := t.FSContext().RootDirectory() err := fn(root, root, name, linux.MaxSymlinkTraversals) - root.DecRef() + root.DecRef(t) return err } else if dir == "." && dirFD == linux.AT_FDCWD { // Common case: we are accessing a file relative to the current @@ -48,8 +48,8 @@ func fileOpAt(t *kernel.Task, dirFD int32, path string, fn func(root *fs.Dirent, wd := t.FSContext().WorkingDirectory() root := t.FSContext().RootDirectory() err := fn(root, wd, name, linux.MaxSymlinkTraversals) - wd.DecRef() - root.DecRef() + wd.DecRef(t) + root.DecRef(t) return err } @@ -97,19 +97,19 @@ func fileOpOn(t *kernel.Task, dirFD int32, path string, resolve bool, fn func(ro } else { d, err = t.MountNamespace().FindLink(t, root, rel, path, &remainingTraversals) } - root.DecRef() + root.DecRef(t) if wd != nil { - wd.DecRef() + wd.DecRef(t) } if f != nil { - f.DecRef() + f.DecRef(t) } if err != nil { return err } err = fn(root, d, remainingTraversals) - d.DecRef() + d.DecRef(t) return err } @@ -130,6 +130,8 @@ func copyInPath(t *kernel.Task, addr usermem.Addr, allowEmpty bool) (path string return path, dirPath, nil } +// LINT.IfChange + func openAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint) (fd uintptr, err error) { path, dirPath, err := copyInPath(t, addr, false /* allowEmpty */) if err != nil { @@ -169,10 +171,14 @@ func openAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint) (fd uint if dirPath { return syserror.ENOTDIR } - if flags&linux.O_TRUNC != 0 { - if err := d.Inode.Truncate(t, d, 0); err != nil { - return err - } + } + + // Truncate is called when O_TRUNC is specified for any kind of + // existing Dirent. Behavior is delegated to the entry's Truncate + // implementation. + if flags&linux.O_TRUNC != 0 { + if err := d.Inode.Truncate(t, d, 0); err != nil { + return err } } @@ -180,7 +186,7 @@ func openAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint) (fd uint if err != nil { return syserror.ConvertIntr(err, kernel.ERESTARTSYS) } - defer file.DecRef() + defer file.DecRef(t) // Success. newFD, err := t.NewFDFrom(0, file, kernel.FDFlags{ @@ -236,7 +242,7 @@ func mknodAt(t *kernel.Task, dirFD int32, addr usermem.Addr, mode linux.FileMode if err != nil { return err } - file.DecRef() + file.DecRef(t) return nil case linux.ModeNamedPipe: @@ -326,7 +332,7 @@ func createAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint, mode l if err != nil { break } - defer found.DecRef() + defer found.DecRef(t) // We found something (possibly a symlink). If the // O_EXCL flag was passed, then we can immediately @@ -351,7 +357,7 @@ func createAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint, mode l resolved, err = found.Inode.Getlink(t) if err == nil { // No more resolution necessary. - defer resolved.DecRef() + defer resolved.DecRef(t) break } if err != fs.ErrResolveViaReadlink { @@ -378,7 +384,7 @@ func createAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint, mode l if err != nil { break } - defer newParent.DecRef() + defer newParent.DecRef(t) // Repeat the process with the parent and name of the // symlink target. @@ -396,7 +402,9 @@ func createAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint, mode l return err } - // Should we truncate the file? + // Truncate is called when O_TRUNC is specified for any kind of + // existing Dirent. Behavior is delegated to the entry's Truncate + // implementation. if flags&linux.O_TRUNC != 0 { if err := found.Inode.Truncate(t, found, 0); err != nil { return err @@ -408,7 +416,7 @@ func createAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint, mode l if err != nil { return syserror.ConvertIntr(err, kernel.ERESTARTSYS) } - defer newFile.DecRef() + defer newFile.DecRef(t) case syserror.ENOENT: // File does not exist. Proceed with creation. @@ -424,7 +432,7 @@ func createAt(t *kernel.Task, dirFD int32, addr usermem.Addr, flags uint, mode l // No luck, bail. return err } - defer newFile.DecRef() + defer newFile.DecRef(t) found = newFile.Dirent default: return err @@ -506,7 +514,7 @@ func (ac accessContext) Value(key interface{}) interface{} { } } -func accessAt(t *kernel.Task, dirFD int32, addr usermem.Addr, resolve bool, mode uint) error { +func accessAt(t *kernel.Task, dirFD int32, addr usermem.Addr, mode uint) error { const rOK = 4 const wOK = 2 const xOK = 1 @@ -521,7 +529,7 @@ func accessAt(t *kernel.Task, dirFD int32, addr usermem.Addr, resolve bool, mode return syserror.EINVAL } - return fileOpOn(t, dirFD, path, resolve, func(root *fs.Dirent, d *fs.Dirent, _ uint) error { + return fileOpOn(t, dirFD, path, true /* resolve */, func(root *fs.Dirent, d *fs.Dirent, _ uint) error { // access(2) and faccessat(2) check permissions using real // UID/GID, not effective UID/GID. // @@ -556,19 +564,29 @@ func Access(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal addr := args[0].Pointer() mode := args[1].ModeT() - return 0, nil, accessAt(t, linux.AT_FDCWD, addr, true, mode) + return 0, nil, accessAt(t, linux.AT_FDCWD, addr, mode) } // Faccessat implements linux syscall faccessat(2). +// +// Note that the faccessat() system call does not take a flags argument: +// "The raw faccessat() system call takes only the first three arguments. The +// AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented within +// the glibc wrapper function for faccessat(). If either of these flags is +// specified, then the wrapper function employs fstatat(2) to determine access +// permissions." - faccessat(2) func Faccessat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { dirFD := args[0].Int() addr := args[1].Pointer() mode := args[2].ModeT() - flags := args[3].Int() - return 0, nil, accessAt(t, dirFD, addr, flags&linux.AT_SYMLINK_NOFOLLOW == 0, mode) + return 0, nil, accessAt(t, dirFD, addr, mode) } +// LINT.ThenChange(vfs2/filesystem.go) + +// LINT.IfChange + // Ioctl implements linux syscall ioctl(2). func Ioctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { fd := args[0].Int() @@ -578,7 +596,7 @@ func Ioctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Shared flags between file and socket. switch request { @@ -644,14 +662,18 @@ func Ioctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } } +// LINT.ThenChange(vfs2/ioctl.go) + +// LINT.IfChange + // Getcwd implements the linux syscall getcwd(2). func Getcwd(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { addr := args[0].Pointer() size := args[1].SizeT() cwd := t.FSContext().WorkingDirectory() - defer cwd.DecRef() + defer cwd.DecRef(t) root := t.FSContext().RootDirectory() - defer root.DecRef() + defer root.DecRef(t) // Get our fullname from the root and preprend unreachable if the root was // unreachable from our current dirent this is the same behavior as on linux. @@ -700,7 +722,7 @@ func Chroot(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal return err } - t.FSContext().SetRootDirectory(d) + t.FSContext().SetRootDirectory(t, d) return nil }) } @@ -725,7 +747,7 @@ func Chdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return err } - t.FSContext().SetWorkingDirectory(d) + t.FSContext().SetWorkingDirectory(t, d) return nil }) } @@ -738,7 +760,7 @@ func Fchdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Is it a directory? if !fs.IsDir(file.Dirent.Inode.StableAttr) { @@ -750,10 +772,14 @@ func Fchdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal return 0, nil, err } - t.FSContext().SetWorkingDirectory(file.Dirent) + t.FSContext().SetWorkingDirectory(t, file.Dirent) return 0, nil, nil } +// LINT.ThenChange(vfs2/fscontext.go) + +// LINT.IfChange + // Close implements linux syscall close(2). func Close(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { fd := args[0].Int() @@ -761,11 +787,11 @@ func Close(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall // Note that Remove provides a reference on the file that we may use to // flush. It is still active until we drop the final reference below // (and other reference-holding operations complete). - file := t.FDTable().Remove(fd) + file, _ := t.FDTable().Remove(fd) if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) err := file.Flush(t) return 0, nil, handleIOError(t, false /* partial */, err, syserror.EINTR, "close", file) @@ -779,7 +805,7 @@ func Dup(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallCo if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) newFD, err := t.NewFDFrom(0, file, kernel.FDFlags{}) if err != nil { @@ -800,7 +826,7 @@ func Dup2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC if oldFile == nil { return 0, nil, syserror.EBADF } - defer oldFile.DecRef() + defer oldFile.DecRef(t) return uintptr(newfd), nil, nil } @@ -824,7 +850,7 @@ func Dup3(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC if oldFile == nil { return 0, nil, syserror.EBADF } - defer oldFile.DecRef() + defer oldFile.DecRef(t) err := t.NewFDAt(newfd, oldFile, kernel.FDFlags{CloseOnExec: flags&linux.O_CLOEXEC != 0}) if err != nil { @@ -834,37 +860,60 @@ func Dup3(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC return uintptr(newfd), nil, nil } -func fGetOwn(t *kernel.Task, file *fs.File) int32 { +func fGetOwnEx(t *kernel.Task, file *fs.File) linux.FOwnerEx { ma := file.Async(nil) if ma == nil { - return 0 + return linux.FOwnerEx{} } a := ma.(*fasync.FileAsync) ot, otg, opg := a.Owner() switch { case ot != nil: - return int32(t.PIDNamespace().IDOfTask(ot)) + return linux.FOwnerEx{ + Type: linux.F_OWNER_TID, + PID: int32(t.PIDNamespace().IDOfTask(ot)), + } case otg != nil: - return int32(t.PIDNamespace().IDOfThreadGroup(otg)) + return linux.FOwnerEx{ + Type: linux.F_OWNER_PID, + PID: int32(t.PIDNamespace().IDOfThreadGroup(otg)), + } case opg != nil: - return int32(-t.PIDNamespace().IDOfProcessGroup(opg)) + return linux.FOwnerEx{ + Type: linux.F_OWNER_PGRP, + PID: int32(t.PIDNamespace().IDOfProcessGroup(opg)), + } default: - return 0 + return linux.FOwnerEx{} + } +} + +func fGetOwn(t *kernel.Task, file *fs.File) int32 { + owner := fGetOwnEx(t, file) + if owner.Type == linux.F_OWNER_PGRP { + return -owner.PID } + return owner.PID } // fSetOwn sets the file's owner with the semantics of F_SETOWN in Linux. // // If who is positive, it represents a PID. If negative, it represents a PGID. // If the PID or PGID is invalid, the owner is silently unset. -func fSetOwn(t *kernel.Task, file *fs.File, who int32) { +func fSetOwn(t *kernel.Task, file *fs.File, who int32) error { a := file.Async(fasync.New).(*fasync.FileAsync) if who < 0 { + // Check for overflow before flipping the sign. + if who-1 > who { + return syserror.EINVAL + } pg := t.PIDNamespace().ProcessGroupWithID(kernel.ProcessGroupID(-who)) a.SetOwnerProcessGroup(t, pg) + } else { + tg := t.PIDNamespace().ThreadGroupWithID(kernel.ThreadID(who)) + a.SetOwnerThreadGroup(t, tg) } - tg := t.PIDNamespace().ThreadGroupWithID(kernel.ThreadID(who)) - a.SetOwnerThreadGroup(t, tg) + return nil } // Fcntl implements linux syscall fcntl(2). @@ -876,7 +925,7 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) switch cmd { case linux.F_DUPFD, linux.F_DUPFD_CLOEXEC: @@ -892,14 +941,16 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return uintptr(flags.ToLinuxFDFlags()), nil, nil case linux.F_SETFD: flags := args[2].Uint() - t.FDTable().SetFlags(fd, kernel.FDFlags{ + err := t.FDTable().SetFlags(fd, kernel.FDFlags{ CloseOnExec: flags&linux.FD_CLOEXEC != 0, }) + return 0, nil, err case linux.F_GETFL: return uintptr(file.Flags().ToLinux()), nil, nil case linux.F_SETFL: flags := uint(args[2].Uint()) file.SetFlags(linuxToFlags(flags).Settable()) + return 0, nil, nil case linux.F_SETLK, linux.F_SETLKW: // In Linux the file system can choose to provide lock operations for an inode. // Normally pipe and socket types lack lock operations. We diverge and use a heavy @@ -953,9 +1004,6 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return 0, nil, err } - // The lock uid is that of the Task's FDTable. - lockUniqueID := lock.UniqueID(t.FDTable().ID()) - // These locks don't block; execute the non-blocking operation using the inode's lock // context directly. switch flock.Type { @@ -965,12 +1013,12 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } if cmd == linux.F_SETLK { // Non-blocking lock, provide a nil lock.Blocker. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.ReadLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.ReadLock, rng, nil) { return 0, nil, syserror.EAGAIN } } else { // Blocking lock, pass in the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.ReadLock, rng, t) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.ReadLock, rng, t) { return 0, nil, syserror.EINTR } } @@ -981,18 +1029,18 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } if cmd == linux.F_SETLK { // Non-blocking lock, provide a nil lock.Blocker. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.WriteLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.WriteLock, rng, nil) { return 0, nil, syserror.EAGAIN } } else { // Blocking lock, pass in the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.Posix.LockRegion(lockUniqueID, lock.WriteLock, rng, t) { + if !file.Dirent.Inode.LockCtx.Posix.LockRegion(t.FDTable(), lock.WriteLock, rng, t) { return 0, nil, syserror.EINTR } } return 0, nil, nil case linux.F_UNLCK: - file.Dirent.Inode.LockCtx.Posix.UnlockRegion(lockUniqueID, rng) + file.Dirent.Inode.LockCtx.Posix.UnlockRegion(t.FDTable(), rng) return 0, nil, nil default: return 0, nil, syserror.EINVAL @@ -1000,8 +1048,45 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall case linux.F_GETOWN: return uintptr(fGetOwn(t, file)), nil, nil case linux.F_SETOWN: - fSetOwn(t, file, args[2].Int()) - return 0, nil, nil + return 0, nil, fSetOwn(t, file, args[2].Int()) + case linux.F_GETOWN_EX: + addr := args[2].Pointer() + owner := fGetOwnEx(t, file) + _, err := t.CopyOut(addr, &owner) + return 0, nil, err + case linux.F_SETOWN_EX: + addr := args[2].Pointer() + var owner linux.FOwnerEx + _, err := t.CopyIn(addr, &owner) + if err != nil { + return 0, nil, err + } + a := file.Async(fasync.New).(*fasync.FileAsync) + switch owner.Type { + case linux.F_OWNER_TID: + task := t.PIDNamespace().TaskWithID(kernel.ThreadID(owner.PID)) + if task == nil { + return 0, nil, syserror.ESRCH + } + a.SetOwnerTask(t, task) + return 0, nil, nil + case linux.F_OWNER_PID: + tg := t.PIDNamespace().ThreadGroupWithID(kernel.ThreadID(owner.PID)) + if tg == nil { + return 0, nil, syserror.ESRCH + } + a.SetOwnerThreadGroup(t, tg) + return 0, nil, nil + case linux.F_OWNER_PGRP: + pg := t.PIDNamespace().ProcessGroupWithID(kernel.ProcessGroupID(owner.PID)) + if pg == nil { + return 0, nil, syserror.ESRCH + } + a.SetOwnerProcessGroup(t, pg) + return 0, nil, nil + default: + return 0, nil, syserror.EINVAL + } case linux.F_GET_SEALS: val, err := tmpfs.GetSeals(file.Dirent.Inode) return uintptr(val), nil, err @@ -1029,18 +1114,8 @@ func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall // Everything else is not yet supported. return 0, nil, syserror.EINVAL } - return 0, nil, nil } -const ( - _FADV_NORMAL = 0 - _FADV_RANDOM = 1 - _FADV_SEQUENTIAL = 2 - _FADV_WILLNEED = 3 - _FADV_DONTNEED = 4 - _FADV_NOREUSE = 5 -) - // Fadvise64 implements linux syscall fadvise64(2). // This implementation currently ignores the provided advice. func Fadvise64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { @@ -1057,7 +1132,7 @@ func Fadvise64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // If the FD refers to a pipe or FIFO, return error. if fs.IsPipe(file.Dirent.Inode.StableAttr) { @@ -1065,12 +1140,12 @@ func Fadvise64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys } switch advice { - case _FADV_NORMAL: - case _FADV_RANDOM: - case _FADV_SEQUENTIAL: - case _FADV_WILLNEED: - case _FADV_DONTNEED: - case _FADV_NOREUSE: + case linux.POSIX_FADV_NORMAL: + case linux.POSIX_FADV_RANDOM: + case linux.POSIX_FADV_SEQUENTIAL: + case linux.POSIX_FADV_WILLNEED: + case linux.POSIX_FADV_DONTNEED: + case linux.POSIX_FADV_NOREUSE: default: return 0, nil, syserror.EINVAL } @@ -1096,7 +1171,7 @@ func mkdirAt(t *kernel.Task, dirFD int32, addr usermem.Addr, mode linux.FileMode switch err { case nil: // The directory existed. - defer f.DecRef() + defer f.DecRef(t) return syserror.EEXIST case syserror.EACCES: // Permission denied while walking to the directory. @@ -1156,7 +1231,7 @@ func rmdirAt(t *kernel.Task, dirFD int32, addr usermem.Addr) error { return syserror.ENOTEMPTY } - if err := fs.MayDelete(t, root, d, name); err != nil { + if err := d.MayDelete(t, root, name); err != nil { return err } @@ -1274,7 +1349,7 @@ func linkAt(t *kernel.Task, oldDirFD int32, oldAddr usermem.Addr, newDirFD int32 if target == nil { return syserror.EBADF } - defer target.DecRef() + defer target.DecRef(t) if err := mayLinkAt(t, target.Dirent.Inode); err != nil { return err } @@ -1359,6 +1434,10 @@ func Linkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal return 0, nil, linkAt(t, oldDirFD, oldAddr, newDirFD, newAddr, resolve, allowEmpty) } +// LINT.ThenChange(vfs2/filesystem.go) + +// LINT.IfChange + func readlinkAt(t *kernel.Task, dirFD int32, addr usermem.Addr, bufAddr usermem.Addr, size uint) (copied uintptr, err error) { path, dirPath, err := copyInPath(t, addr, false /* allowEmpty */) if err != nil { @@ -1418,6 +1497,10 @@ func Readlinkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy return n, nil, err } +// LINT.ThenChange(vfs2/stat.go) + +// LINT.IfChange + func unlinkAt(t *kernel.Task, dirFD int32, addr usermem.Addr) error { path, dirPath, err := copyInPath(t, addr, false /* allowEmpty */) if err != nil { @@ -1429,7 +1512,7 @@ func unlinkAt(t *kernel.Task, dirFD int32, addr usermem.Addr) error { return syserror.ENOTDIR } - if err := fs.MayDelete(t, root, d, name); err != nil { + if err := d.MayDelete(t, root, name); err != nil { return err } @@ -1454,6 +1537,10 @@ func Unlinkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc return 0, nil, unlinkAt(t, dirFD, addr) } +// LINT.ThenChange(vfs2/filesystem.go) + +// LINT.IfChange + // Truncate implements linux syscall truncate(2). func Truncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { addr := args[0].Pointer() @@ -1483,6 +1570,8 @@ func Truncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if fs.IsDir(d.Inode.StableAttr) { return syserror.EISDIR } + // In contrast to open(O_TRUNC), truncate(2) is only valid for file + // types. if !fs.IsFile(d.Inode.StableAttr) { return syserror.EINVAL } @@ -1513,7 +1602,7 @@ func Ftruncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Reject truncation if the file flags do not permit this operation. // This is different from truncate(2) above. @@ -1521,7 +1610,8 @@ func Ftruncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys return 0, nil, syserror.EINVAL } - // Note that this is different from truncate(2) above, where a + // In contrast to open(O_TRUNC), truncate(2) is only valid for file + // types. Note that this is different from truncate(2) above, where a // directory returns EISDIR. if !fs.IsFile(file.Dirent.Inode.StableAttr) { return 0, nil, syserror.EINVAL @@ -1549,6 +1639,8 @@ func Ftruncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys return 0, nil, nil } +// LINT.ThenChange(vfs2/setstat.go) + // Umask implements linux syscall umask(2). func Umask(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { mask := args[0].ModeT() @@ -1556,6 +1648,8 @@ func Umask(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return uintptr(mask), nil, nil } +// LINT.IfChange + // Change ownership of a file. // // uid and gid may be -1, in which case they will not be changed. @@ -1636,7 +1730,7 @@ func chownAt(t *kernel.Task, fd int32, addr usermem.Addr, resolve, allowEmpty bo if file == nil { return syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) return chown(t, file.Dirent, uid, gid) } @@ -1674,7 +1768,7 @@ func Fchown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) return 0, nil, chown(t, file.Dirent, uid, gid) } @@ -1739,7 +1833,7 @@ func Fchmod(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) return 0, nil, chmod(t, file.Dirent, mode) } @@ -1799,10 +1893,10 @@ func utimes(t *kernel.Task, dirFD int32, addr usermem.Addr, ts fs.TimeSpec, reso if f == nil { return syserror.EBADF } - defer f.DecRef() + defer f.DecRef(t) root := t.FSContext().RootDirectory() - defer root.DecRef() + defer root.DecRef(t) return setTimestamp(root, f.Dirent, linux.MaxSymlinkTraversals) } @@ -1922,6 +2016,10 @@ func Futimesat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys return 0, nil, utimes(t, dirFD, pathnameAddr, ts, true) } +// LINT.ThenChange(vfs2/setstat.go) + +// LINT.IfChange + func renameAt(t *kernel.Task, oldDirFD int32, oldAddr usermem.Addr, newDirFD int32, newAddr usermem.Addr) error { newPath, _, err := copyInPath(t, newAddr, false /* allowEmpty */) if err != nil { @@ -1977,6 +2075,8 @@ func Renameat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc return 0, nil, renameAt(t, oldDirFD, oldPathAddr, newDirFD, newPathAddr) } +// LINT.ThenChange(vfs2/filesystem.go) + // Fallocate implements linux system call fallocate(2). func Fallocate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { fd := args[0].Int() @@ -1988,7 +2088,7 @@ func Fallocate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) if offset < 0 || length <= 0 { return 0, nil, syserror.EINVAL @@ -2041,27 +2141,11 @@ func Flock(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall // flock(2): EBADF fd is not an open file descriptor. return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) nonblocking := operation&linux.LOCK_NB != 0 operation &^= linux.LOCK_NB - // flock(2): - // Locks created by flock() are associated with an open file table entry. This means that - // duplicate file descriptors (created by, for example, fork(2) or dup(2)) refer to the - // same lock, and this lock may be modified or released using any of these descriptors. Furthermore, - // the lock is released either by an explicit LOCK_UN operation on any of these duplicate - // descriptors, or when all such descriptors have been closed. - // - // If a process uses open(2) (or similar) to obtain more than one descriptor for the same file, - // these descriptors are treated independently by flock(). An attempt to lock the file using - // one of these file descriptors may be denied by a lock that the calling process has already placed via - // another descriptor. - // - // We use the File UniqueID as the lock UniqueID because it needs to reference the same lock across dup(2) - // and fork(2). - lockUniqueID := lock.UniqueID(file.UniqueID) - // A BSD style lock spans the entire file. rng := lock.LockRange{ Start: 0, @@ -2072,29 +2156,29 @@ func Flock(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall case linux.LOCK_EX: if nonblocking { // Since we're nonblocking we pass a nil lock.Blocker implementation. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.WriteLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.WriteLock, rng, nil) { return 0, nil, syserror.EWOULDBLOCK } } else { // Because we're blocking we will pass the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.WriteLock, rng, t) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.WriteLock, rng, t) { return 0, nil, syserror.EINTR } } case linux.LOCK_SH: if nonblocking { // Since we're nonblocking we pass a nil lock.Blocker implementation. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.ReadLock, rng, nil) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.ReadLock, rng, nil) { return 0, nil, syserror.EWOULDBLOCK } } else { // Because we're blocking we will pass the task to satisfy the lock.Blocker interface. - if !file.Dirent.Inode.LockCtx.BSD.LockRegion(lockUniqueID, lock.ReadLock, rng, t) { + if !file.Dirent.Inode.LockCtx.BSD.LockRegion(file, lock.ReadLock, rng, t) { return 0, nil, syserror.EINTR } } case linux.LOCK_UN: - file.Dirent.Inode.LockCtx.BSD.UnlockRegion(lockUniqueID, rng) + file.Dirent.Inode.LockCtx.BSD.UnlockRegion(file, rng) default: // flock(2): EINVAL operation is invalid. return 0, nil, syserror.EINVAL @@ -2140,8 +2224,8 @@ func MemfdCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S return 0, nil, err } - defer dirent.DecRef() - defer file.DecRef() + defer dirent.DecRef(t) + defer file.DecRef(t) newFD, err := t.NewFDFrom(0, file, kernel.FDFlags{ CloseOnExec: cloExec, diff --git a/pkg/sentry/syscalls/linux/sys_futex.go b/pkg/sentry/syscalls/linux/sys_futex.go index b9bd25464..9d1b2edb1 100644 --- a/pkg/sentry/syscalls/linux/sys_futex.go +++ b/pkg/sentry/syscalls/linux/sys_futex.go @@ -21,8 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // futexWaitRestartBlock encapsulates the state required to restart futex(2) @@ -73,7 +73,7 @@ func futexWaitAbsolute(t *kernel.Task, clockRealtime bool, ts linux.Timespec, fo err = t.BlockWithDeadline(w.C, true, ktime.FromTimespec(ts)) } - t.Futex().WaitComplete(w) + t.Futex().WaitComplete(w, t) return 0, syserror.ConvertIntr(err, kernel.ERESTARTSYS) } @@ -95,7 +95,7 @@ func futexWaitDuration(t *kernel.Task, duration time.Duration, forever bool, add } remaining, err := t.BlockWithTimeout(w.C, !forever, duration) - t.Futex().WaitComplete(w) + t.Futex().WaitComplete(w, t) if err == nil { return 0, nil } @@ -148,7 +148,7 @@ func futexLockPI(t *kernel.Task, ts linux.Timespec, forever bool, addr usermem.A timer.Destroy() } - t.Futex().WaitComplete(w) + t.Futex().WaitComplete(w, t) return syserror.ConvertIntr(err, kernel.ERESTARTSYS) } @@ -198,7 +198,7 @@ func Futex(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall switch cmd { case linux.FUTEX_WAIT: // WAIT uses a relative timeout. - mask = ^uint32(0) + mask = linux.FUTEX_BITSET_MATCH_ANY var timeoutDur time.Duration if !forever { timeoutDur = time.Duration(timespec.ToNsecCapped()) * time.Nanosecond @@ -226,6 +226,11 @@ func Futex(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if mask == 0 { return 0, nil, syserror.EINVAL } + if val <= 0 { + // The Linux kernel wakes one waiter even if val is + // non-positive. + val = 1 + } n, err := t.Futex().Wake(t, addr, private, mask, val) return uintptr(n), nil, err @@ -242,6 +247,11 @@ func Futex(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall case linux.FUTEX_WAKE_OP: op := uint32(val3) + if val <= 0 { + // The Linux kernel wakes one waiter even if val is + // non-positive. + val = 1 + } n, err := t.Futex().WakeOp(t, addr, naddr, private, val, nreq, op) return uintptr(n), nil, err @@ -276,3 +286,49 @@ func Futex(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return 0, nil, syserror.ENOSYS } } + +// SetRobustList implements linux syscall set_robust_list(2). +func SetRobustList(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + // Despite the syscall using the name 'pid' for this variable, it is + // very much a tid. + head := args[0].Pointer() + length := args[1].SizeT() + + if length != uint(linux.SizeOfRobustListHead) { + return 0, nil, syserror.EINVAL + } + t.SetRobustList(head) + return 0, nil, nil +} + +// GetRobustList implements linux syscall get_robust_list(2). +func GetRobustList(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + // Despite the syscall using the name 'pid' for this variable, it is + // very much a tid. + tid := args[0].Int() + head := args[1].Pointer() + size := args[2].Pointer() + + if tid < 0 { + return 0, nil, syserror.EINVAL + } + + ot := t + if tid != 0 { + if ot = t.PIDNamespace().TaskWithID(kernel.ThreadID(tid)); ot == nil { + return 0, nil, syserror.ESRCH + } + } + + // Copy out head pointer. + if _, err := t.CopyOut(head, uint64(ot.GetRobustList())); err != nil { + return 0, nil, err + } + + // Copy out size, which is a constant. + if _, err := t.CopyOut(size, uint64(linux.SizeOfRobustListHead)); err != nil { + return 0, nil, err + } + + return 0, nil, nil +} diff --git a/pkg/sentry/syscalls/linux/sys_getdents.go b/pkg/sentry/syscalls/linux/sys_getdents.go index 912cbe4ff..f5699e55d 100644 --- a/pkg/sentry/syscalls/linux/sys_getdents.go +++ b/pkg/sentry/syscalls/linux/sys_getdents.go @@ -23,10 +23,12 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) +// LINT.IfChange + // Getdents implements linux syscall getdents(2) for 64bit systems. func Getdents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { fd := args[0].Int() @@ -66,7 +68,7 @@ func getdents(t *kernel.Task, fd int32, addr usermem.Addr, size int, f func(*dir if dir == nil { return 0, syserror.EBADF } - defer dir.DecRef() + defer dir.DecRef(t) w := &usermem.IOReadWriter{ Ctx: t, @@ -244,3 +246,5 @@ func (ds *direntSerializer) CopyOut(name string, attr fs.DentAttr) error { func (ds *direntSerializer) Written() int { return ds.written } + +// LINT.ThenChange(vfs2/getdents.go) diff --git a/pkg/sentry/syscalls/linux/sys_inotify.go b/pkg/sentry/syscalls/linux/sys_inotify.go index b2c7b3444..cf47bb9dd 100644 --- a/pkg/sentry/syscalls/linux/sys_inotify.go +++ b/pkg/sentry/syscalls/linux/sys_inotify.go @@ -40,7 +40,7 @@ func InotifyInit1(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel. NonBlocking: flags&linux.IN_NONBLOCK != 0, } n := fs.NewFile(t, dirent, fileFlags, fs.NewInotify(t)) - defer n.DecRef() + defer n.DecRef(t) fd, err := t.NewFDFrom(0, n, kernel.FDFlags{ CloseOnExec: flags&linux.IN_CLOEXEC != 0, @@ -71,7 +71,7 @@ func fdToInotify(t *kernel.Task, fd int32) (*fs.Inotify, *fs.File, error) { ino, ok := file.FileOperations.(*fs.Inotify) if !ok { // Not an inotify fd. - file.DecRef() + file.DecRef(t) return nil, nil, syserror.EINVAL } @@ -98,7 +98,7 @@ func InotifyAddWatch(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kern if err != nil { return 0, nil, err } - defer file.DecRef() + defer file.DecRef(t) path, _, err := copyInPath(t, addr, false /* allowEmpty */) if err != nil { @@ -128,6 +128,6 @@ func InotifyRmWatch(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne if err != nil { return 0, nil, err } - defer file.DecRef() - return 0, nil, ino.RmWatch(wd) + defer file.DecRef(t) + return 0, nil, ino.RmWatch(t, wd) } diff --git a/pkg/sentry/syscalls/linux/sys_lseek.go b/pkg/sentry/syscalls/linux/sys_lseek.go index 297e920c4..1c38f8f4f 100644 --- a/pkg/sentry/syscalls/linux/sys_lseek.go +++ b/pkg/sentry/syscalls/linux/sys_lseek.go @@ -21,6 +21,8 @@ import ( "gvisor.dev/gvisor/pkg/syserror" ) +// LINT.IfChange + // Lseek implements linux syscall lseek(2). func Lseek(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { fd := args[0].Int() @@ -31,7 +33,7 @@ func Lseek(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) var sw fs.SeekWhence switch whence { @@ -52,3 +54,5 @@ func Lseek(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } return uintptr(offset), nil, err } + +// LINT.ThenChange(vfs2/read_write.go) diff --git a/pkg/sentry/syscalls/linux/sys_mempolicy.go b/pkg/sentry/syscalls/linux/sys_mempolicy.go index f5a519d8a..9b4a5c3f1 100644 --- a/pkg/sentry/syscalls/linux/sys_mempolicy.go +++ b/pkg/sentry/syscalls/linux/sys_mempolicy.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // We unconditionally report a single NUMA node. This also means that our @@ -162,10 +162,10 @@ func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel. if err != nil { return 0, nil, err } - policy = 0 // maxNodes == 1 + policy = linux.MPOL_DEFAULT // maxNodes == 1 } if mode != 0 { - if _, err := t.CopyOut(mode, policy); err != nil { + if _, err := policy.CopyOut(t, mode); err != nil { return 0, nil, err } } @@ -199,10 +199,10 @@ func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel. if policy&^linux.MPOL_MODE_FLAGS != linux.MPOL_INTERLEAVE { return 0, nil, syserror.EINVAL } - policy = 0 // maxNodes == 1 + policy = linux.MPOL_DEFAULT // maxNodes == 1 } if mode != 0 { - if _, err := t.CopyOut(mode, policy); err != nil { + if _, err := policy.CopyOut(t, mode); err != nil { return 0, nil, err } } @@ -216,7 +216,7 @@ func GetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel. // SetMempolicy implements the syscall set_mempolicy(2). func SetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - modeWithFlags := args[0].Int() + modeWithFlags := linux.NumaPolicy(args[0].Int()) nodemask := args[1].Pointer() maxnode := args[2].Uint() @@ -233,7 +233,7 @@ func SetMempolicy(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel. func Mbind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { addr := args[0].Pointer() length := args[1].Uint64() - mode := args[2].Int() + mode := linux.NumaPolicy(args[2].Int()) nodemask := args[3].Pointer() maxnode := args[4].Uint() flags := args[5].Uint() @@ -258,9 +258,9 @@ func Mbind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall return 0, nil, err } -func copyInMempolicyNodemask(t *kernel.Task, modeWithFlags int32, nodemask usermem.Addr, maxnode uint32) (int32, uint64, error) { - flags := modeWithFlags & linux.MPOL_MODE_FLAGS - mode := modeWithFlags &^ linux.MPOL_MODE_FLAGS +func copyInMempolicyNodemask(t *kernel.Task, modeWithFlags linux.NumaPolicy, nodemask usermem.Addr, maxnode uint32) (linux.NumaPolicy, uint64, error) { + flags := linux.NumaPolicy(modeWithFlags & linux.MPOL_MODE_FLAGS) + mode := linux.NumaPolicy(modeWithFlags &^ linux.MPOL_MODE_FLAGS) if flags == linux.MPOL_MODE_FLAGS { // Can't specify both mode flags simultaneously. return 0, 0, syserror.EINVAL diff --git a/pkg/sentry/syscalls/linux/sys_mmap.go b/pkg/sentry/syscalls/linux/sys_mmap.go index 58a05b5bb..72786b032 100644 --- a/pkg/sentry/syscalls/linux/sys_mmap.go +++ b/pkg/sentry/syscalls/linux/sys_mmap.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/memmap" "gvisor.dev/gvisor/pkg/sentry/mm" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Brk implements linux syscall brk(2). @@ -35,6 +35,8 @@ func Brk(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallCo return uintptr(addr), nil, nil } +// LINT.IfChange + // Mmap implements linux syscall mmap(2). func Mmap(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { prot := args[2].Int() @@ -73,7 +75,7 @@ func Mmap(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC } defer func() { if opts.MappingIdentity != nil { - opts.MappingIdentity.DecRef() + opts.MappingIdentity.DecRef(t) } }() @@ -83,7 +85,7 @@ func Mmap(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) flags := file.Flags() // mmap unconditionally requires that the FD is readable. @@ -104,6 +106,8 @@ func Mmap(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC return uintptr(rv), nil, err } +// LINT.ThenChange(vfs2/mmap.go) + // Munmap implements linux syscall munmap(2). func Munmap(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { return 0, nil, t.MemoryManager().MUnmap(t, args[0].Pointer(), args[1].Uint64()) diff --git a/pkg/sentry/syscalls/linux/sys_mount.go b/pkg/sentry/syscalls/linux/sys_mount.go index 8c13e2d82..bd0633564 100644 --- a/pkg/sentry/syscalls/linux/sys_mount.go +++ b/pkg/sentry/syscalls/linux/sys_mount.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // Mount implements Linux syscall mount(2). @@ -115,7 +115,7 @@ func Mount(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall }); err != nil { // Something went wrong. Drop our ref on rootInode before // returning the error. - rootInode.DecRef() + rootInode.DecRef(t) return 0, nil, err } diff --git a/pkg/sentry/syscalls/linux/sys_pipe.go b/pkg/sentry/syscalls/linux/sys_pipe.go index 418d7fa5f..3149e4aad 100644 --- a/pkg/sentry/syscalls/linux/sys_pipe.go +++ b/pkg/sentry/syscalls/linux/sys_pipe.go @@ -20,10 +20,12 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) +// LINT.IfChange + // pipe2 implements the actual system call with flags. func pipe2(t *kernel.Task, addr usermem.Addr, flags uint) (uintptr, error) { if flags&^(linux.O_NONBLOCK|linux.O_CLOEXEC) != 0 { @@ -32,10 +34,10 @@ func pipe2(t *kernel.Task, addr usermem.Addr, flags uint) (uintptr, error) { r, w := pipe.NewConnectedPipe(t, pipe.DefaultPipeSize, usermem.PageSize) r.SetFlags(linuxToFlags(flags).Settable()) - defer r.DecRef() + defer r.DecRef(t) w.SetFlags(linuxToFlags(flags).Settable()) - defer w.DecRef() + defer w.DecRef(t) fds, err := t.NewFDs(0, []*fs.File{r, w}, kernel.FDFlags{ CloseOnExec: flags&linux.O_CLOEXEC != 0, @@ -45,10 +47,12 @@ func pipe2(t *kernel.Task, addr usermem.Addr, flags uint) (uintptr, error) { } if _, err := t.CopyOut(addr, fds); err != nil { - // The files are not closed in this case, the exact semantics - // of this error case are not well defined, but they could have - // already been observed by user space. - return 0, syserror.EFAULT + for _, fd := range fds { + if file, _ := t.FDTable().Remove(fd); file != nil { + file.DecRef(t) + } + } + return 0, err } return 0, nil } @@ -69,3 +73,5 @@ func Pipe2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall n, err := pipe2(t, addr, flags) return n, nil, err } + +// LINT.ThenChange(vfs2/pipe.go) diff --git a/pkg/sentry/syscalls/linux/sys_poll.go b/pkg/sentry/syscalls/linux/sys_poll.go index 7a13beac2..3435bdf77 100644 --- a/pkg/sentry/syscalls/linux/sys_poll.go +++ b/pkg/sentry/syscalls/linux/sys_poll.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) @@ -70,7 +70,7 @@ func initReadiness(t *kernel.Task, pfd *linux.PollFD, state *pollState, ch chan } if ch == nil { - defer file.DecRef() + defer file.DecRef(t) } else { state.file = file state.waiter, _ = waiter.NewChannelEntry(ch) @@ -82,11 +82,11 @@ func initReadiness(t *kernel.Task, pfd *linux.PollFD, state *pollState, ch chan } // releaseState releases all the pollState in "state". -func releaseState(state []pollState) { +func releaseState(t *kernel.Task, state []pollState) { for i := range state { if state[i].file != nil { state[i].file.EventUnregister(&state[i].waiter) - state[i].file.DecRef() + state[i].file.DecRef(t) } } } @@ -107,7 +107,7 @@ func pollBlock(t *kernel.Task, pfd []linux.PollFD, timeout time.Duration) (time. // result, we stop registering for events but still go through all files // to get their ready masks. state := make([]pollState, len(pfd)) - defer releaseState(state) + defer releaseState(t, state) n := uintptr(0) for i := range pfd { initReadiness(t, &pfd[i], &state[i], ch) @@ -197,53 +197,51 @@ func doPoll(t *kernel.Task, addr usermem.Addr, nfds uint, timeout time.Duration) return remainingTimeout, n, err } +// CopyInFDSet copies an fd set from select(2)/pselect(2). +func CopyInFDSet(t *kernel.Task, addr usermem.Addr, nBytes, nBitsInLastPartialByte int) ([]byte, error) { + set := make([]byte, nBytes) + + if addr != 0 { + if _, err := t.CopyIn(addr, &set); err != nil { + return nil, err + } + // If we only use part of the last byte, mask out the extraneous bits. + // + // N.B. This only works on little-endian architectures. + if nBitsInLastPartialByte != 0 { + set[nBytes-1] &^= byte(0xff) << nBitsInLastPartialByte + } + } + return set, nil +} + func doSelect(t *kernel.Task, nfds int, readFDs, writeFDs, exceptFDs usermem.Addr, timeout time.Duration) (uintptr, error) { if nfds < 0 || nfds > fileCap { return 0, syserror.EINVAL } - // Capture all the provided input vectors. - // - // N.B. This only works on little-endian architectures. - byteCount := (nfds + 7) / 8 - - bitsInLastPartialByte := uint(nfds % 8) - r := make([]byte, byteCount) - w := make([]byte, byteCount) - e := make([]byte, byteCount) + // Calculate the size of the fd sets (one bit per fd). + nBytes := (nfds + 7) / 8 + nBitsInLastPartialByte := nfds % 8 - if readFDs != 0 { - if _, err := t.CopyIn(readFDs, &r); err != nil { - return 0, err - } - // Mask out bits above nfds. - if bitsInLastPartialByte != 0 { - r[byteCount-1] &^= byte(0xff) << bitsInLastPartialByte - } + // Capture all the provided input vectors. + r, err := CopyInFDSet(t, readFDs, nBytes, nBitsInLastPartialByte) + if err != nil { + return 0, err } - - if writeFDs != 0 { - if _, err := t.CopyIn(writeFDs, &w); err != nil { - return 0, err - } - if bitsInLastPartialByte != 0 { - w[byteCount-1] &^= byte(0xff) << bitsInLastPartialByte - } + w, err := CopyInFDSet(t, writeFDs, nBytes, nBitsInLastPartialByte) + if err != nil { + return 0, err } - - if exceptFDs != 0 { - if _, err := t.CopyIn(exceptFDs, &e); err != nil { - return 0, err - } - if bitsInLastPartialByte != 0 { - e[byteCount-1] &^= byte(0xff) << bitsInLastPartialByte - } + e, err := CopyInFDSet(t, exceptFDs, nBytes, nBitsInLastPartialByte) + if err != nil { + return 0, err } // Count how many FDs are actually being requested so that we can build // a PollFD array. fdCount := 0 - for i := 0; i < byteCount; i++ { + for i := 0; i < nBytes; i++ { v := r[i] | w[i] | e[i] for v != 0 { v &= (v - 1) @@ -254,7 +252,7 @@ func doSelect(t *kernel.Task, nfds int, readFDs, writeFDs, exceptFDs usermem.Add // Build the PollFD array. pfd := make([]linux.PollFD, 0, fdCount) var fd int32 - for i := 0; i < byteCount; i++ { + for i := 0; i < nBytes; i++ { rV, wV, eV := r[i], w[i], e[i] v := rV | wV | eV m := byte(1) @@ -268,7 +266,7 @@ func doSelect(t *kernel.Task, nfds int, readFDs, writeFDs, exceptFDs usermem.Add if file == nil { return 0, syserror.EBADF } - file.DecRef() + file.DecRef(t) var mask int16 if (rV & m) != 0 { @@ -295,8 +293,7 @@ func doSelect(t *kernel.Task, nfds int, readFDs, writeFDs, exceptFDs usermem.Add } // Do the syscall, then count the number of bits set. - _, _, err := pollBlock(t, pfd, timeout) - if err != nil { + if _, _, err = pollBlock(t, pfd, timeout); err != nil { return 0, syserror.ConvertIntr(err, syserror.EINTR) } @@ -446,7 +443,7 @@ func Ppoll(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } if maskAddr != 0 { - mask, err := copyInSigSet(t, maskAddr, maskSize) + mask, err := CopyInSigSet(t, maskAddr, maskSize) if err != nil { return 0, nil, err } @@ -528,7 +525,7 @@ func Pselect(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca } if maskAddr != 0 { - mask, err := copyInSigSet(t, maskAddr, size) + mask, err := CopyInSigSet(t, maskAddr, size) if err != nil { return 0, nil, err } diff --git a/pkg/sentry/syscalls/linux/sys_prctl.go b/pkg/sentry/syscalls/linux/sys_prctl.go index 98db32d77..64a725296 100644 --- a/pkg/sentry/syscalls/linux/sys_prctl.go +++ b/pkg/sentry/syscalls/linux/sys_prctl.go @@ -20,6 +20,7 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" "gvisor.dev/gvisor/pkg/sentry/mm" @@ -127,7 +128,7 @@ func Prctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // They trying to set exe to a non-file? if !fs.IsFile(file.Dirent.Inode.StableAttr) { @@ -135,7 +136,7 @@ func Prctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall } // Set the underlying executable. - t.MemoryManager().SetExecutable(file.Dirent) + t.MemoryManager().SetExecutable(t, fsbridge.NewFSFile(file)) case linux.PR_SET_MM_AUXV, linux.PR_SET_MM_START_CODE, @@ -160,8 +161,8 @@ func Prctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if args[1].Int() != 1 || args[2].Int() != 0 || args[3].Int() != 0 || args[4].Int() != 0 { return 0, nil, syserror.EINVAL } - // no_new_privs is assumed to always be set. See - // kernel.Task.updateCredsForExec. + // PR_SET_NO_NEW_PRIVS is assumed to always be set. + // See kernel.Task.updateCredsForExecLocked. return 0, nil, nil case linux.PR_GET_NO_NEW_PRIVS: diff --git a/pkg/sentry/syscalls/linux/sys_random.go b/pkg/sentry/syscalls/linux/sys_random.go index bc4c588bf..c0aa0fd60 100644 --- a/pkg/sentry/syscalls/linux/sys_random.go +++ b/pkg/sentry/syscalls/linux/sys_random.go @@ -19,11 +19,11 @@ import ( "math" "gvisor.dev/gvisor/pkg/rand" + "gvisor.dev/gvisor/pkg/safemem" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/safemem" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( diff --git a/pkg/sentry/syscalls/linux/sys_read.go b/pkg/sentry/syscalls/linux/sys_read.go index cd31e0649..3bbc3fa4b 100644 --- a/pkg/sentry/syscalls/linux/sys_read.go +++ b/pkg/sentry/syscalls/linux/sys_read.go @@ -23,13 +23,15 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) +// LINT.IfChange + const ( - // EventMaskRead contains events that can be triggerd on reads. + // EventMaskRead contains events that can be triggered on reads. EventMaskRead = waiter.EventIn | waiter.EventHUp | waiter.EventErr ) @@ -46,7 +48,7 @@ func Read(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the file is readable. if !file.Flags().Read { @@ -82,7 +84,7 @@ func Readahead(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the file is readable. if !file.Flags().Read { @@ -94,8 +96,8 @@ func Readahead(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys return 0, nil, syserror.EINVAL } - // Check that the offset is legitimate. - if offset < 0 { + // Check that the offset is legitimate and does not overflow. + if offset < 0 || offset+int64(size) < 0 { return 0, nil, syserror.EINVAL } @@ -116,10 +118,10 @@ func Pread64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) - // Check that the offset is legitimate. - if offset < 0 { + // Check that the offset is legitimate and does not overflow. + if offset < 0 || offset+int64(size) < 0 { return 0, nil, syserror.EINVAL } @@ -162,7 +164,7 @@ func Readv(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the file is readable. if !file.Flags().Read { @@ -193,7 +195,7 @@ func Preadv(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the offset is legitimate. if offset < 0 { @@ -242,7 +244,7 @@ func Preadv2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the offset is legitimate. if offset < -1 { @@ -388,3 +390,5 @@ func preadv(t *kernel.Task, f *fs.File, dst usermem.IOSequence, offset int64) (i return total, err } + +// LINT.ThenChange(vfs2/read_write.go) diff --git a/pkg/sentry/syscalls/linux/sys_rlimit.go b/pkg/sentry/syscalls/linux/sys_rlimit.go index 51e3f836b..d5d5b6959 100644 --- a/pkg/sentry/syscalls/linux/sys_rlimit.go +++ b/pkg/sentry/syscalls/linux/sys_rlimit.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/limits" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // rlimit describes an implementation of 'struct rlimit', which may vary from @@ -197,7 +197,7 @@ func Prlimit64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys // saved set user IDs of the target process must match the real user ID of // the caller and the real, effective, and saved set group IDs of the // target process must match the real group ID of the caller." - if !t.HasCapabilityIn(linux.CAP_SYS_RESOURCE, t.PIDNamespace().UserNamespace()) { + if ot != t && !t.HasCapabilityIn(linux.CAP_SYS_RESOURCE, t.PIDNamespace().UserNamespace()) { cred, tcred := t.Credentials(), ot.Credentials() if cred.RealKUID != tcred.RealKUID || cred.RealKUID != tcred.EffectiveKUID || diff --git a/pkg/sentry/syscalls/linux/sys_rseq.go b/pkg/sentry/syscalls/linux/sys_rseq.go new file mode 100644 index 000000000..90db10ea6 --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_rseq.go @@ -0,0 +1,48 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package linux + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// RSeq implements syscall rseq(2). +func RSeq(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + length := args[1].Uint() + flags := args[2].Int() + signature := args[3].Uint() + + if !t.RSeqAvailable() { + // Event for applications that want rseq on a configuration + // that doesn't support them. + t.Kernel().EmitUnimplementedEvent(t) + return 0, nil, syserror.ENOSYS + } + + switch flags { + case 0: + // Register. + return 0, nil, t.SetRSeq(addr, length, signature) + case linux.RSEQ_FLAG_UNREGISTER: + return 0, nil, t.ClearRSeq(addr, length, signature) + default: + // Unknown flag. + return 0, nil, syserror.EINVAL + } +} diff --git a/pkg/sentry/syscalls/linux/sys_seccomp.go b/pkg/sentry/syscalls/linux/sys_seccomp.go index 18510ead8..5b7a66f4d 100644 --- a/pkg/sentry/syscalls/linux/sys_seccomp.go +++ b/pkg/sentry/syscalls/linux/sys_seccomp.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/bpf" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // userSockFprog is equivalent to Linux's struct sock_fprog on amd64. diff --git a/pkg/sentry/syscalls/linux/sys_sem.go b/pkg/sentry/syscalls/linux/sys_sem.go index cde3b54e7..5f54f2456 100644 --- a/pkg/sentry/syscalls/linux/sys_sem.go +++ b/pkg/sentry/syscalls/linux/sys_sem.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const opsMax = 500 // SEMOPM diff --git a/pkg/sentry/syscalls/linux/sys_shm.go b/pkg/sentry/syscalls/linux/sys_shm.go index d57ffb3a1..f0ae8fa8e 100644 --- a/pkg/sentry/syscalls/linux/sys_shm.go +++ b/pkg/sentry/syscalls/linux/sys_shm.go @@ -39,10 +39,13 @@ func Shmget(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if err != nil { return 0, nil, err } + defer segment.DecRef(t) return uintptr(segment.ID), nil, nil } // findSegment retrives a shm segment by the given id. +// +// findSegment returns a reference on Shm. func findSegment(t *kernel.Task, id shm.ID) (*shm.Shm, error) { r := t.IPCNamespace().ShmRegistry() segment := r.FindByID(id) @@ -63,6 +66,7 @@ func Shmat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if err != nil { return 0, nil, syserror.EINVAL } + defer segment.DecRef(t) opts, err := segment.ConfigureAttach(t, addr, shm.AttachOpts{ Execute: flag&linux.SHM_EXEC == linux.SHM_EXEC, @@ -72,7 +76,6 @@ func Shmat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if err != nil { return 0, nil, err } - defer segment.DecRef() addr, err = t.MemoryManager().MMap(t, opts) return uintptr(addr), nil, err } @@ -105,6 +108,7 @@ func Shmctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if err != nil { return 0, nil, syserror.EINVAL } + defer segment.DecRef(t) stat, err := segment.IPCStat(t) if err == nil { @@ -128,6 +132,7 @@ func Shmctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if err != nil { return 0, nil, syserror.EINVAL } + defer segment.DecRef(t) switch cmd { case linux.IPC_SET: @@ -140,7 +145,7 @@ func Shmctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal return 0, nil, err case linux.IPC_RMID: - segment.MarkDestroyed() + segment.MarkDestroyed(t) return 0, nil, nil case linux.SHM_LOCK, linux.SHM_UNLOCK: diff --git a/pkg/sentry/syscalls/linux/sys_signal.go b/pkg/sentry/syscalls/linux/sys_signal.go index fb6efd5d8..20cb1a5cb 100644 --- a/pkg/sentry/syscalls/linux/sys_signal.go +++ b/pkg/sentry/syscalls/linux/sys_signal.go @@ -23,8 +23,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/signalfd" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // "For a process to have permission to send a signal it must @@ -245,6 +245,11 @@ func RtSigaction(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S sig := linux.Signal(args[0].Int()) newactarg := args[1].Pointer() oldactarg := args[2].Pointer() + sigsetsize := args[3].SizeT() + + if sigsetsize != linux.SignalSetSize { + return 0, nil, syserror.EINVAL + } var newactptr *arch.SignalAct if newactarg != 0 { @@ -290,7 +295,7 @@ func RtSigprocmask(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel } oldmask := t.SignalMask() if setaddr != 0 { - mask, err := copyInSigSet(t, setaddr, sigsetsize) + mask, err := CopyInSigSet(t, setaddr, sigsetsize) if err != nil { return 0, nil, err } @@ -350,7 +355,7 @@ func Pause(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall func RtSigpending(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { addr := args[0].Pointer() pending := t.PendingSignals() - _, err := t.CopyOut(addr, pending) + _, err := pending.CopyOut(t, addr) return 0, nil, err } @@ -361,7 +366,7 @@ func RtSigtimedwait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne timespec := args[2].Pointer() sigsetsize := args[3].SizeT() - mask, err := copyInSigSet(t, sigset, sigsetsize) + mask, err := CopyInSigSet(t, sigset, sigsetsize) if err != nil { return 0, nil, err } @@ -387,7 +392,7 @@ func RtSigtimedwait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne if siginfo != 0 { si.FixSignalCodeForUser() - if _, err := t.CopyOut(siginfo, si); err != nil { + if _, err := si.CopyOut(t, siginfo); err != nil { return 0, nil, err } } @@ -406,7 +411,7 @@ func RtSigqueueinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne // same way), and that the code is in the allowed set. This same logic // appears below in RtSigtgqueueinfo and should be kept in sync. var info arch.SignalInfo - if _, err := t.CopyIn(infoAddr, &info); err != nil { + if _, err := info.CopyIn(t, infoAddr); err != nil { return 0, nil, err } info.Signo = int32(sig) @@ -450,7 +455,7 @@ func RtTgsigqueueinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *ker // Copy in the info. See RtSigqueueinfo above. var info arch.SignalInfo - if _, err := t.CopyIn(infoAddr, &info); err != nil { + if _, err := info.CopyIn(t, infoAddr); err != nil { return 0, nil, err } info.Signo = int32(sig) @@ -480,7 +485,7 @@ func RtSigsuspend(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel. // Copy in the signal mask. var mask linux.SignalSet - if _, err := t.CopyIn(sigset, &mask); err != nil { + if _, err := mask.CopyIn(t, sigset); err != nil { return 0, nil, err } mask &^= kernel.UnblockableSignals @@ -513,7 +518,7 @@ func RestartSyscall(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne // sharedSignalfd is shared between the two calls. func sharedSignalfd(t *kernel.Task, fd int32, sigset usermem.Addr, sigsetsize uint, flags int32) (uintptr, *kernel.SyscallControl, error) { // Copy in the signal mask. - mask, err := copyInSigSet(t, sigset, sigsetsize) + mask, err := CopyInSigSet(t, sigset, sigsetsize) if err != nil { return 0, nil, err } @@ -531,7 +536,7 @@ func sharedSignalfd(t *kernel.Task, fd int32, sigset usermem.Addr, sigsetsize ui if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Is this a signalfd? if s, ok := file.FileOperations.(*signalfd.SignalOperations); ok { @@ -548,7 +553,7 @@ func sharedSignalfd(t *kernel.Task, fd int32, sigset usermem.Addr, sigsetsize ui if err != nil { return 0, nil, err } - defer file.DecRef() + defer file.DecRef(t) // Set appropriate flags. file.SetFlags(fs.SettableFileFlags{ diff --git a/pkg/sentry/syscalls/linux/sys_socket.go b/pkg/sentry/syscalls/linux/sys_socket.go index b5a72ce63..fec1c1974 100644 --- a/pkg/sentry/syscalls/linux/sys_socket.go +++ b/pkg/sentry/syscalls/linux/sys_socket.go @@ -26,11 +26,15 @@ import ( "gvisor.dev/gvisor/pkg/sentry/socket" "gvisor.dev/gvisor/pkg/sentry/socket/control" "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserr" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/tools/go_marshal/marshal" + "gvisor.dev/gvisor/tools/go_marshal/primitive" ) +// LINT.IfChange + // minListenBacklog is the minimum reasonable backlog for listening sockets. const minListenBacklog = 8 @@ -41,7 +45,7 @@ const maxListenBacklog = 1024 const maxAddrLen = 200 // maxOptLen is the maximum sockopt parameter length we're willing to accept. -const maxOptLen = 1024 +const maxOptLen = 1024 * 8 // maxControlLen is the maximum length of the msghdr.msg_control buffer we're // willing to accept. Note that this limit is smaller than Linux, which allows @@ -196,7 +200,7 @@ func Socket(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal s.SetFlags(fs.SettableFileFlags{ NonBlocking: stype&linux.SOCK_NONBLOCK != 0, }) - defer s.DecRef() + defer s.DecRef(t) fd, err := t.NewFDFrom(0, s, kernel.FDFlags{ CloseOnExec: stype&linux.SOCK_CLOEXEC != 0, @@ -231,8 +235,8 @@ func SocketPair(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy } s1.SetFlags(fileFlags) s2.SetFlags(fileFlags) - defer s1.DecRef() - defer s2.DecRef() + defer s1.DecRef(t) + defer s2.DecRef(t) // Create the FDs for the sockets. fds, err := t.NewFDs(0, []*fs.File{s1, s2}, kernel.FDFlags{ @@ -244,7 +248,11 @@ func SocketPair(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy // Copy the file descriptors out. if _, err := t.CopyOut(socks, fds); err != nil { - // Note that we don't close files here; see pipe(2) also. + for _, fd := range fds { + if file, _ := t.FDTable().Remove(fd); file != nil { + file.DecRef(t) + } + } return 0, nil, err } @@ -262,7 +270,7 @@ func Connect(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -293,7 +301,7 @@ func accept(t *kernel.Task, fd int32, addr usermem.Addr, addrLen usermem.Addr, f if file == nil { return 0, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -352,7 +360,7 @@ func Bind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallC if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -379,7 +387,7 @@ func Listen(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -408,7 +416,7 @@ func Shutdown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -439,7 +447,7 @@ func GetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -447,16 +455,13 @@ func GetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy return 0, nil, syserror.ENOTSOCK } - // Read the length if present. Reject negative values. + // Read the length. Reject negative values. optLen := int32(0) - if optLenAddr != 0 { - if _, err := t.CopyIn(optLenAddr, &optLen); err != nil { - return 0, nil, err - } - - if optLen < 0 { - return 0, nil, syserror.EINVAL - } + if _, err := t.CopyIn(optLenAddr, &optLen); err != nil { + return 0, nil, err + } + if optLen < 0 { + return 0, nil, syserror.EINVAL } // Call syscall implementation then copy both value and value len out. @@ -465,15 +470,13 @@ func GetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy return 0, nil, e.ToError() } - if optLenAddr != 0 { - vLen := int32(binary.Size(v)) - if _, err := t.CopyOut(optLenAddr, vLen); err != nil { - return 0, nil, err - } + vLen := int32(binary.Size(v)) + if _, err := t.CopyOut(optLenAddr, vLen); err != nil { + return 0, nil, err } if v != nil { - if _, err := t.CopyOut(optValAddr, v); err != nil { + if _, err := v.CopyOut(t, optValAddr); err != nil { return 0, nil, err } } @@ -483,7 +486,7 @@ func GetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy // getSockOpt tries to handle common socket options, or dispatches to a specific // socket implementation. -func getSockOpt(t *kernel.Task, s socket.Socket, level, name int, optValAddr usermem.Addr, len int) (interface{}, *syserr.Error) { +func getSockOpt(t *kernel.Task, s socket.Socket, level, name int, optValAddr usermem.Addr, len int) (marshal.Marshallable, *syserr.Error) { if level == linux.SOL_SOCKET { switch name { case linux.SO_TYPE, linux.SO_DOMAIN, linux.SO_PROTOCOL: @@ -495,13 +498,16 @@ func getSockOpt(t *kernel.Task, s socket.Socket, level, name int, optValAddr use switch name { case linux.SO_TYPE: _, skType, _ := s.Type() - return int32(skType), nil + v := primitive.Int32(skType) + return &v, nil case linux.SO_DOMAIN: family, _, _ := s.Type() - return int32(family), nil + v := primitive.Int32(family) + return &v, nil case linux.SO_PROTOCOL: _, _, protocol := s.Type() - return int32(protocol), nil + v := primitive.Int32(protocol) + return &v, nil } } @@ -523,7 +529,7 @@ func SetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -538,7 +544,7 @@ func SetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sy return 0, nil, syserror.EINVAL } buf := t.CopyScratchBuffer(int(optLen)) - if _, err := t.CopyIn(optValAddr, &buf); err != nil { + if _, err := t.CopyInBytes(optValAddr, buf); err != nil { return 0, nil, err } @@ -561,7 +567,7 @@ func GetSockName(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -589,7 +595,7 @@ func GetPeerName(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -622,7 +628,7 @@ func RecvMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -675,7 +681,7 @@ func RecvMMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -769,7 +775,7 @@ func recvSingleMsg(t *kernel.Task, s socket.Socket, msgPtr usermem.Addr, flags i } if !cms.Unix.Empty() { mflags |= linux.MSG_CTRUNC - cms.Unix.Release() + cms.Release(t) } if int(msg.Flags) != mflags { @@ -789,24 +795,16 @@ func recvSingleMsg(t *kernel.Task, s socket.Socket, msgPtr usermem.Addr, flags i if e != nil { return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS) } - defer cms.Unix.Release() + defer cms.Release(t) controlData := make([]byte, 0, msg.ControlLen) + controlData = control.PackControlMessages(t, cms, controlData) if cr, ok := s.(transport.Credentialer); ok && cr.Passcred() { creds, _ := cms.Unix.Credentials.(control.SCMCredentials) controlData, mflags = control.PackCredentials(t, creds, controlData, mflags) } - if cms.IP.HasTimestamp { - controlData = control.PackTimestamp(t, cms.IP.Timestamp, controlData) - } - - if cms.IP.HasInq { - // In Linux, TCP_CM_INQ is added after SO_TIMESTAMP. - controlData = control.PackInq(t, cms.IP.Inq, controlData) - } - if cms.Unix.Rights != nil { controlData, mflags = control.PackRights(t, cms.Unix.Rights.(control.SCMRights), flags&linux.MSG_CMSG_CLOEXEC != 0, controlData, mflags) } @@ -853,7 +851,7 @@ func recvFrom(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flag if file == nil { return 0, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -882,7 +880,7 @@ func recvFrom(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flag } n, _, sender, senderLen, cm, e := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, nameLenPtr != 0, 0) - cm.Unix.Release() + cm.Release(t) if e != nil { return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS) } @@ -926,7 +924,7 @@ func SendMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -964,7 +962,7 @@ func SendMMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -1065,10 +1063,10 @@ func sendSingleMsg(t *kernel.Task, s socket.Socket, file *fs.File, msgPtr userme } // Call the syscall implementation. - n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, socket.ControlMessages{Unix: controlMessages}) + n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, controlMessages) err = handleIOError(t, n != 0, e.ToError(), kernel.ERESTARTSYS, "sendmsg", file) if err != nil { - controlMessages.Release() + controlMessages.Release(t) } return uintptr(n), err } @@ -1086,7 +1084,7 @@ func sendTo(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flags if file == nil { return 0, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Extract the socket. s, ok := file.FileOperations.(socket.Socket) @@ -1141,3 +1139,5 @@ func SendTo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal n, err := sendTo(t, fd, bufPtr, bufLen, flags, namePtr, nameLen) return n, nil, err } + +// LINT.ThenChange(./vfs2/socket.go) diff --git a/pkg/sentry/syscalls/linux/sys_splice.go b/pkg/sentry/syscalls/linux/sys_splice.go index dd3a5807f..b8846a10a 100644 --- a/pkg/sentry/syscalls/linux/sys_splice.go +++ b/pkg/sentry/syscalls/linux/sys_splice.go @@ -25,6 +25,14 @@ import ( // doSplice implements a blocking splice operation. func doSplice(t *kernel.Task, outFile, inFile *fs.File, opts fs.SpliceOpts, nonBlocking bool) (int64, error) { + if opts.Length < 0 || opts.SrcStart < 0 || opts.DstStart < 0 || (opts.SrcStart+opts.Length < 0) { + return 0, syserror.EINVAL + } + + if opts.Length > int64(kernel.MAX_RW_COUNT) { + opts.Length = int64(kernel.MAX_RW_COUNT) + } + var ( total int64 n int64 @@ -72,6 +80,12 @@ func doSplice(t *kernel.Task, outFile, inFile *fs.File, opts fs.SpliceOpts, nonB } } + if total > 0 { + // On Linux, inotify behavior is not very consistent with splice(2). We try + // our best to emulate Linux for very basic calls to splice, where for some + // reason, events are generated for output files, but not input files. + outFile.Dirent.InotifyEvent(linux.IN_MODIFY, 0) + } return total, err } @@ -82,17 +96,12 @@ func Sendfile(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc offsetAddr := args[2].Pointer() count := int64(args[3].SizeT()) - // Don't send a negative number of bytes. - if count < 0 { - return 0, nil, syserror.EINVAL - } - // Get files. inFile := t.GetFile(inFD) if inFile == nil { return 0, nil, syserror.EBADF } - defer inFile.DecRef() + defer inFile.DecRef(t) if !inFile.Flags().Read { return 0, nil, syserror.EBADF @@ -102,7 +111,7 @@ func Sendfile(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if outFile == nil { return 0, nil, syserror.EBADF } - defer outFile.DecRef() + defer outFile.DecRef(t) if !outFile.Flags().Write { return 0, nil, syserror.EBADF @@ -136,11 +145,6 @@ func Sendfile(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc return 0, nil, err } - // The offset must be valid. - if offset < 0 { - return 0, nil, syserror.EINVAL - } - // Do the splice. n, err = doSplice(t, outFile, inFile, fs.SpliceOpts{ Length: count, @@ -188,13 +192,13 @@ func Splice(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if outFile == nil { return 0, nil, syserror.EBADF } - defer outFile.DecRef() + defer outFile.DecRef(t) inFile := t.GetFile(inFD) if inFile == nil { return 0, nil, syserror.EBADF } - defer inFile.DecRef() + defer inFile.DecRef(t) // The operation is non-blocking if anything is non-blocking. // @@ -211,8 +215,10 @@ func Splice(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal opts := fs.SpliceOpts{ Length: count, } + inFileAttr := inFile.Dirent.Inode.StableAttr + outFileAttr := outFile.Dirent.Inode.StableAttr switch { - case fs.IsPipe(inFile.Dirent.Inode.StableAttr) && !fs.IsPipe(outFile.Dirent.Inode.StableAttr): + case fs.IsPipe(inFileAttr) && !fs.IsPipe(outFileAttr): if inOffset != 0 { return 0, nil, syserror.ESPIPE } @@ -225,11 +231,12 @@ func Splice(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if _, err := t.CopyIn(outOffset, &offset); err != nil { return 0, nil, err } + // Use the destination offset. opts.DstOffset = true opts.DstStart = offset } - case !fs.IsPipe(inFile.Dirent.Inode.StableAttr) && fs.IsPipe(outFile.Dirent.Inode.StableAttr): + case !fs.IsPipe(inFileAttr) && fs.IsPipe(outFileAttr): if outOffset != 0 { return 0, nil, syserror.ESPIPE } @@ -242,17 +249,18 @@ func Splice(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if _, err := t.CopyIn(inOffset, &offset); err != nil { return 0, nil, err } + // Use the source offset. opts.SrcOffset = true opts.SrcStart = offset } - case fs.IsPipe(inFile.Dirent.Inode.StableAttr) && fs.IsPipe(outFile.Dirent.Inode.StableAttr): + case fs.IsPipe(inFileAttr) && fs.IsPipe(outFileAttr): if inOffset != 0 || outOffset != 0 { return 0, nil, syserror.ESPIPE } // We may not refer to the same pipe; otherwise it's a continuous loop. - if inFile.Dirent.Inode.StableAttr.InodeID == outFile.Dirent.Inode.StableAttr.InodeID { + if inFileAttr.InodeID == outFileAttr.InodeID { return 0, nil, syserror.EINVAL } default: @@ -262,6 +270,15 @@ func Splice(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal // Splice data. n, err := doSplice(t, outFile, inFile, opts, nonBlock) + // Special files can have additional requirements for granularity. For + // example, read from eventfd returns EINVAL if a size is less 8 bytes. + // Inotify is another example. read will return EINVAL is a buffer is + // too small to return the next event, but a size of an event isn't + // fixed, it is sizeof(struct inotify_event) + {NAME_LEN} + 1. + if n != 0 && err != nil && (fs.IsAnonymous(inFileAttr) || fs.IsAnonymous(outFileAttr)) { + err = nil + } + // See above; inFile is chosen arbitrarily here. return uintptr(n), nil, handleIOError(t, n != 0, err, kernel.ERESTARTSYS, "splice", inFile) } @@ -283,13 +300,13 @@ func Tee(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallCo if outFile == nil { return 0, nil, syserror.EBADF } - defer outFile.DecRef() + defer outFile.DecRef(t) inFile := t.GetFile(inFD) if inFile == nil { return 0, nil, syserror.EBADF } - defer inFile.DecRef() + defer inFile.DecRef(t) // All files must be pipes. if !fs.IsPipe(inFile.Dirent.Inode.StableAttr) || !fs.IsPipe(outFile.Dirent.Inode.StableAttr) { diff --git a/pkg/sentry/syscalls/linux/sys_stat.go b/pkg/sentry/syscalls/linux/sys_stat.go index 5556bc276..a5826f2dd 100644 --- a/pkg/sentry/syscalls/linux/sys_stat.go +++ b/pkg/sentry/syscalls/linux/sys_stat.go @@ -16,14 +16,15 @@ package linux import ( "gvisor.dev/gvisor/pkg/abi/linux" - "gvisor.dev/gvisor/pkg/binary" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) +// LINT.IfChange + // Stat implements linux syscall stat(2). func Stat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { addr := args[0].Pointer() @@ -57,7 +58,7 @@ func Fstatat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) return 0, nil, fstat(t, file, statAddr) } @@ -99,7 +100,7 @@ func Fstat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) return 0, nil, fstat(t, file, statAddr) } @@ -113,7 +114,9 @@ func stat(t *kernel.Task, d *fs.Dirent, dirPath bool, statAddr usermem.Addr) err if err != nil { return err } - return copyOutStat(t, statAddr, d.Inode.StableAttr, uattr) + s := statFromAttrs(t, d.Inode.StableAttr, uattr) + _, err = s.CopyOut(t, statAddr) + return err } // fstat implements fstat for the given *fs.File. @@ -122,56 +125,8 @@ func fstat(t *kernel.Task, f *fs.File, statAddr usermem.Addr) error { if err != nil { return err } - return copyOutStat(t, statAddr, f.Dirent.Inode.StableAttr, uattr) -} - -// copyOutStat copies the attributes (sattr, uattr) to the struct stat at -// address dst in t's address space. It encodes the stat struct to bytes -// manually, as stat() is a very common syscall for many applications, and -// t.CopyObjectOut has noticeable performance impact due to its many slice -// allocations and use of reflection. -func copyOutStat(t *kernel.Task, dst usermem.Addr, sattr fs.StableAttr, uattr fs.UnstableAttr) error { - b := t.CopyScratchBuffer(int(linux.SizeOfStat))[:0] - - // Dev (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(sattr.DeviceID)) - // Ino (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(sattr.InodeID)) - // Nlink (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uattr.Links) - // Mode (uint32) - b = binary.AppendUint32(b, usermem.ByteOrder, sattr.Type.LinuxType()|uint32(uattr.Perms.LinuxMode())) - // UID (uint32) - b = binary.AppendUint32(b, usermem.ByteOrder, uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow())) - // GID (uint32) - b = binary.AppendUint32(b, usermem.ByteOrder, uint32(uattr.Owner.GID.In(t.UserNamespace()).OrOverflow())) - // Padding (uint32) - b = binary.AppendUint32(b, usermem.ByteOrder, 0) - // Rdev (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor))) - // Size (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(uattr.Size)) - // Blksize (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(sattr.BlockSize)) - // Blocks (uint64) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(uattr.Usage/512)) - - // ATime - atime := uattr.AccessTime.Timespec() - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(atime.Sec)) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(atime.Nsec)) - - // MTime - mtime := uattr.ModificationTime.Timespec() - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(mtime.Sec)) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(mtime.Nsec)) - - // CTime - ctime := uattr.StatusChangeTime.Timespec() - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(ctime.Sec)) - b = binary.AppendUint64(b, usermem.ByteOrder, uint64(ctime.Nsec)) - - _, err := t.CopyOutBytes(dst, b) + s := statFromAttrs(t, f.Dirent.Inode.StableAttr, uattr) + _, err = s.CopyOut(t, statAddr) return err } @@ -183,7 +138,10 @@ func Statx(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall mask := args[3].Uint() statxAddr := args[4].Pointer() - if mask&linux.STATX__RESERVED > 0 { + if mask&linux.STATX__RESERVED != 0 { + return 0, nil, syserror.EINVAL + } + if flags&^(linux.AT_SYMLINK_NOFOLLOW|linux.AT_EMPTY_PATH|linux.AT_STATX_SYNC_TYPE) != 0 { return 0, nil, syserror.EINVAL } if flags&linux.AT_STATX_SYNC_TYPE == linux.AT_STATX_SYNC_TYPE { @@ -200,7 +158,7 @@ func Statx(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) uattr, err := file.UnstableAttr(t) if err != nil { return 0, nil, err @@ -291,7 +249,7 @@ func Fstatfs(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) return 0, nil, statfsImpl(t, file.Dirent, statfsAddr) } @@ -328,3 +286,5 @@ func statfsImpl(t *kernel.Task, d *fs.Dirent, addr usermem.Addr) error { _, err = t.CopyOut(addr, &statfs) return err } + +// LINT.ThenChange(vfs2/stat.go) diff --git a/pkg/sentry/syscalls/linux/sys_stat_amd64.go b/pkg/sentry/syscalls/linux/sys_stat_amd64.go new file mode 100644 index 000000000..0a04a6113 --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_stat_amd64.go @@ -0,0 +1,45 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build amd64 + +package linux + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/kernel" +) + +// LINT.IfChange + +func statFromAttrs(t *kernel.Task, sattr fs.StableAttr, uattr fs.UnstableAttr) linux.Stat { + return linux.Stat{ + Dev: sattr.DeviceID, + Ino: sattr.InodeID, + Nlink: uattr.Links, + Mode: sattr.Type.LinuxType() | uint32(uattr.Perms.LinuxMode()), + UID: uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow()), + GID: uint32(uattr.Owner.GID.In(t.UserNamespace()).OrOverflow()), + Rdev: uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor)), + Size: uattr.Size, + Blksize: sattr.BlockSize, + Blocks: uattr.Usage / 512, + ATime: uattr.AccessTime.Timespec(), + MTime: uattr.ModificationTime.Timespec(), + CTime: uattr.StatusChangeTime.Timespec(), + } +} + +// LINT.ThenChange(vfs2/stat_amd64.go) diff --git a/pkg/sentry/syscalls/linux/sys_stat_arm64.go b/pkg/sentry/syscalls/linux/sys_stat_arm64.go new file mode 100644 index 000000000..5a3b1bfad --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_stat_arm64.go @@ -0,0 +1,45 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build arm64 + +package linux + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/kernel" +) + +// LINT.IfChange + +func statFromAttrs(t *kernel.Task, sattr fs.StableAttr, uattr fs.UnstableAttr) linux.Stat { + return linux.Stat{ + Dev: sattr.DeviceID, + Ino: sattr.InodeID, + Nlink: uint32(uattr.Links), + Mode: sattr.Type.LinuxType() | uint32(uattr.Perms.LinuxMode()), + UID: uint32(uattr.Owner.UID.In(t.UserNamespace()).OrOverflow()), + GID: uint32(uattr.Owner.GID.In(t.UserNamespace()).OrOverflow()), + Rdev: uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor)), + Size: uattr.Size, + Blksize: int32(sattr.BlockSize), + Blocks: uattr.Usage / 512, + ATime: uattr.AccessTime.Timespec(), + MTime: uattr.ModificationTime.Timespec(), + CTime: uattr.StatusChangeTime.Timespec(), + } +} + +// LINT.ThenChange(vfs2/stat_arm64.go) diff --git a/pkg/sentry/syscalls/linux/sys_sync.go b/pkg/sentry/syscalls/linux/sys_sync.go index 3e55235bd..f2c0e5069 100644 --- a/pkg/sentry/syscalls/linux/sys_sync.go +++ b/pkg/sentry/syscalls/linux/sys_sync.go @@ -22,6 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/syserror" ) +// LINT.IfChange + // Sync implements linux system call sync(2). func Sync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { t.MountNamespace().SyncAll(t) @@ -37,7 +39,7 @@ func Syncfs(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Use "sync-the-world" for now, it's guaranteed that fd is at least // on the root filesystem. @@ -52,7 +54,7 @@ func Fsync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) err := file.Fsync(t, 0, fs.FileMaxOffset, fs.SyncAll) return 0, nil, syserror.ConvertIntr(err, kernel.ERESTARTSYS) @@ -68,7 +70,7 @@ func Fdatasync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sys if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) err := file.Fsync(t, 0, fs.FileMaxOffset, fs.SyncData) return 0, nil, syserror.ConvertIntr(err, kernel.ERESTARTSYS) @@ -101,7 +103,7 @@ func SyncFileRange(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // SYNC_FILE_RANGE_WAIT_BEFORE waits upon write-out of all pages in the // specified range that have already been submitted to the device @@ -135,3 +137,5 @@ func SyncFileRange(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel return 0, nil, syserror.ConvertIntr(err, kernel.ERESTARTSYS) } + +// LINT.ThenChange(vfs2/sync.go) diff --git a/pkg/sentry/syscalls/linux/sys_sysinfo.go b/pkg/sentry/syscalls/linux/sys_sysinfo.go index a65b560c8..297de052a 100644 --- a/pkg/sentry/syscalls/linux/sys_sysinfo.go +++ b/pkg/sentry/syscalls/linux/sys_sysinfo.go @@ -29,13 +29,18 @@ func Sysinfo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca mf.UpdateUsage() _, totalUsage := usage.MemoryAccounting.Copy() totalSize := usage.TotalMemory(mf.TotalSize(), totalUsage) + memFree := totalSize - totalUsage + if memFree > totalSize { + // Underflow. + memFree = 0 + } // Only a subset of the fields in sysinfo_t make sense to return. si := linux.Sysinfo{ Procs: uint16(len(t.PIDNamespace().Tasks())), Uptime: t.Kernel().MonotonicClock().Now().Seconds(), TotalRAM: totalSize, - FreeRAM: totalSize - totalUsage, + FreeRAM: memFree, Unit: 1, } _, err := t.CopyOut(addr, si) diff --git a/pkg/sentry/syscalls/linux/sys_thread.go b/pkg/sentry/syscalls/linux/sys_thread.go index 2476f8858..2d16e4933 100644 --- a/pkg/sentry/syscalls/linux/sys_thread.go +++ b/pkg/sentry/syscalls/linux/sys_thread.go @@ -21,11 +21,12 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" "gvisor.dev/gvisor/pkg/sentry/kernel" "gvisor.dev/gvisor/pkg/sentry/kernel/sched" "gvisor.dev/gvisor/pkg/sentry/loader" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const ( @@ -116,10 +117,11 @@ func execveat(t *kernel.Task, dirFD int32, pathnameAddr, argvAddr, envvAddr user resolveFinal := flags&linux.AT_SYMLINK_NOFOLLOW == 0 root := t.FSContext().RootDirectory() - defer root.DecRef() + defer root.DecRef(t) var wd *fs.Dirent - var executable *fs.File + var executable fsbridge.File + var closeOnExec bool if dirFD == linux.AT_FDCWD || path.IsAbs(pathname) { // Even if the pathname is absolute, we may still need the wd // for interpreter scripts if the path of the interpreter is @@ -127,14 +129,23 @@ func execveat(t *kernel.Task, dirFD int32, pathnameAddr, argvAddr, envvAddr user wd = t.FSContext().WorkingDirectory() } else { // Need to extract the given FD. - f := t.GetFile(dirFD) + f, fdFlags := t.FDTable().Get(dirFD) if f == nil { return 0, nil, syserror.EBADF } - defer f.DecRef() + defer f.DecRef(t) + closeOnExec = fdFlags.CloseOnExec if atEmptyPath && len(pathname) == 0 { - executable = f + // TODO(gvisor.dev/issue/160): Linux requires only execute permission, + // not read. However, our backing filesystems may prevent us from reading + // the file without read permission. Additionally, a task with a + // non-readable executable has additional constraints on access via + // ptrace and procfs. + if err := f.Dirent.Inode.CheckPermission(t, fs.PermMask{Read: true, Execute: true}); err != nil { + return 0, nil, err + } + executable = fsbridge.NewFSFile(f) } else { wd = f.Dirent wd.IncRef() @@ -144,19 +155,18 @@ func execveat(t *kernel.Task, dirFD int32, pathnameAddr, argvAddr, envvAddr user } } if wd != nil { - defer wd.DecRef() + defer wd.DecRef(t) } // Load the new TaskContext. remainingTraversals := uint(linux.MaxSymlinkTraversals) loadArgs := loader.LoadArgs{ - Mounts: t.MountNamespace(), - Root: root, - WorkingDirectory: wd, + Opener: fsbridge.NewFSLookup(t.MountNamespace(), root, wd), RemainingTraversals: &remainingTraversals, ResolveFinal: resolveFinal, Filename: pathname, File: executable, + CloseOnExec: closeOnExec, Argv: argv, Envv: envv, Features: t.Arch().FeatureSet(), @@ -217,19 +227,6 @@ func clone(t *kernel.Task, flags int, stack usermem.Addr, parentTID usermem.Addr return uintptr(ntid), ctrl, err } -// Clone implements linux syscall clone(2). -// sys_clone has so many flavors. We implement the default one in linux 3.11 -// x86_64: -// sys_clone(clone_flags, newsp, parent_tidptr, child_tidptr, tls_val) -func Clone(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { - flags := int(args[0].Int()) - stack := args[1].Pointer() - parentTID := args[2].Pointer() - childTID := args[3].Pointer() - tls := args[4].Pointer() - return clone(t, flags, stack, parentTID, childTID, tls) -} - // Fork implements Linux syscall fork(2). func Fork(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { // "A call to fork() is equivalent to a call to clone(2) specifying flags diff --git a/pkg/sentry/syscalls/linux/sys_time.go b/pkg/sentry/syscalls/linux/sys_time.go index b887fa9d7..2d2aa0819 100644 --- a/pkg/sentry/syscalls/linux/sys_time.go +++ b/pkg/sentry/syscalls/linux/sys_time.go @@ -22,8 +22,8 @@ import ( "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // The most significant 29 bits hold either a pid or a file descriptor. diff --git a/pkg/sentry/syscalls/linux/sys_timer.go b/pkg/sentry/syscalls/linux/sys_timer.go index d4134207b..a4c400f87 100644 --- a/pkg/sentry/syscalls/linux/sys_timer.go +++ b/pkg/sentry/syscalls/linux/sys_timer.go @@ -20,8 +20,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/arch" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) const nsecPerSec = int64(time.Second) @@ -146,7 +146,7 @@ func TimerCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.S return 0, nil, err } - return uintptr(id), nil, nil + return 0, nil, nil } // TimerSettime implements linux syscall timer_settime(2). diff --git a/pkg/sentry/syscalls/linux/sys_timerfd.go b/pkg/sentry/syscalls/linux/sys_timerfd.go index cf49b43db..34b03e4ee 100644 --- a/pkg/sentry/syscalls/linux/sys_timerfd.go +++ b/pkg/sentry/syscalls/linux/sys_timerfd.go @@ -43,7 +43,7 @@ func TimerfdCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel return 0, nil, syserror.EINVAL } f := timerfd.NewFile(t, c) - defer f.DecRef() + defer f.DecRef(t) f.SetFlags(fs.SettableFileFlags{ NonBlocking: flags&linux.TFD_NONBLOCK != 0, }) @@ -73,7 +73,7 @@ func TimerfdSettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne if f == nil { return 0, nil, syserror.EBADF } - defer f.DecRef() + defer f.DecRef(t) tf, ok := f.FileOperations.(*timerfd.TimerOperations) if !ok { @@ -107,7 +107,7 @@ func TimerfdGettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kerne if f == nil { return 0, nil, syserror.EBADF } - defer f.DecRef() + defer f.DecRef(t) tf, ok := f.FileOperations.(*timerfd.TimerOperations) if !ok { diff --git a/pkg/sentry/syscalls/linux/sys_tls.go b/pkg/sentry/syscalls/linux/sys_tls_amd64.go index b3eb96a1c..b3eb96a1c 100644 --- a/pkg/sentry/syscalls/linux/sys_tls.go +++ b/pkg/sentry/syscalls/linux/sys_tls_amd64.go diff --git a/pkg/sentry/syscalls/linux/sys_tls_arm64.go b/pkg/sentry/syscalls/linux/sys_tls_arm64.go new file mode 100644 index 000000000..fb08a356e --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_tls_arm64.go @@ -0,0 +1,28 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +//+build arm64 + +package linux + +import ( + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// ArchPrctl is not defined for ARM64. +func ArchPrctl(*kernel.Task, arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, syserror.ENOSYS +} diff --git a/pkg/sentry/syscalls/linux/sys_utsname.go b/pkg/sentry/syscalls/linux/sys_utsname.go index 748e8dd8d..e9d702e8e 100644 --- a/pkg/sentry/syscalls/linux/sys_utsname.go +++ b/pkg/sentry/syscalls/linux/sys_utsname.go @@ -12,8 +12,6 @@ // See the License for the specific language governing permissions and // limitations under the License. -// +build amd64 - package linux import ( @@ -35,7 +33,15 @@ func Uname(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall copy(u.Nodename[:], uts.HostName()) copy(u.Release[:], version.Release) copy(u.Version[:], version.Version) - copy(u.Machine[:], "x86_64") // build tag above. + // build tag above. + switch t.SyscallTable().Arch { + case arch.AMD64: + copy(u.Machine[:], "x86_64") + case arch.ARM64: + copy(u.Machine[:], "aarch64") + default: + copy(u.Machine[:], "unknown") + } copy(u.Domainname[:], uts.DomainName()) // Copy out the result. diff --git a/pkg/sentry/syscalls/linux/sys_write.go b/pkg/sentry/syscalls/linux/sys_write.go index ad4b67806..485526e28 100644 --- a/pkg/sentry/syscalls/linux/sys_write.go +++ b/pkg/sentry/syscalls/linux/sys_write.go @@ -23,11 +23,13 @@ import ( "gvisor.dev/gvisor/pkg/sentry/kernel" ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/socket" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" "gvisor.dev/gvisor/pkg/waiter" ) +// LINT.IfChange + const ( // EventMaskWrite contains events that can be triggered on writes. // @@ -46,7 +48,7 @@ func Write(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscall if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the file is writable. if !file.Flags().Write { @@ -83,10 +85,10 @@ func Pwrite64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) - // Check that the offset is legitimate. - if offset < 0 { + // Check that the offset is legitimate and does not overflow. + if offset < 0 || offset+int64(size) < 0 { return 0, nil, syserror.EINVAL } @@ -129,7 +131,7 @@ func Writev(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the file is writable. if !file.Flags().Write { @@ -160,7 +162,7 @@ func Pwritev(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysca if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the offset is legitimate. if offset < 0 { @@ -213,7 +215,7 @@ func Pwritev2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Sysc if file == nil { return 0, nil, syserror.EBADF } - defer file.DecRef() + defer file.DecRef(t) // Check that the offset is legitimate. if offset < -1 { @@ -358,3 +360,5 @@ func pwritev(t *kernel.Task, f *fs.File, src usermem.IOSequence, offset int64) ( return total, err } + +// LINT.ThenChange(vfs2/read_write.go) diff --git a/pkg/sentry/syscalls/linux/sys_xattr.go b/pkg/sentry/syscalls/linux/sys_xattr.go new file mode 100644 index 000000000..97474fd3c --- /dev/null +++ b/pkg/sentry/syscalls/linux/sys_xattr.go @@ -0,0 +1,432 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package linux + +import ( + "strings" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// LINT.IfChange + +// GetXattr implements linux syscall getxattr(2). +func GetXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return getXattrFromPath(t, args, true) +} + +// LGetXattr implements linux syscall lgetxattr(2). +func LGetXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return getXattrFromPath(t, args, false) +} + +// FGetXattr implements linux syscall fgetxattr(2). +func FGetXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := uint64(args[3].SizeT()) + + // TODO(b/113957122): Return EBADF if the fd was opened with O_PATH. + f := t.GetFile(fd) + if f == nil { + return 0, nil, syserror.EBADF + } + defer f.DecRef(t) + + n, err := getXattr(t, f.Dirent, nameAddr, valueAddr, size) + if err != nil { + return 0, nil, err + } + + return uintptr(n), nil, nil +} + +func getXattrFromPath(t *kernel.Task, args arch.SyscallArguments, resolveSymlink bool) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := uint64(args[3].SizeT()) + + path, dirPath, err := copyInPath(t, pathAddr, false /* allowEmpty */) + if err != nil { + return 0, nil, err + } + + n := 0 + err = fileOpOn(t, linux.AT_FDCWD, path, resolveSymlink, func(_ *fs.Dirent, d *fs.Dirent, _ uint) error { + if dirPath && !fs.IsDir(d.Inode.StableAttr) { + return syserror.ENOTDIR + } + + n, err = getXattr(t, d, nameAddr, valueAddr, size) + return err + }) + if err != nil { + return 0, nil, err + } + + return uintptr(n), nil, nil +} + +// getXattr implements getxattr(2) from the given *fs.Dirent. +func getXattr(t *kernel.Task, d *fs.Dirent, nameAddr, valueAddr usermem.Addr, size uint64) (int, error) { + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return 0, err + } + + if err := checkXattrPermissions(t, d.Inode, fs.PermMask{Read: true}); err != nil { + return 0, err + } + + // TODO(b/148380782): Support xattrs in namespaces other than "user". + if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) { + return 0, syserror.EOPNOTSUPP + } + + // If getxattr(2) is called with size 0, the size of the value will be + // returned successfully even if it is nonzero. In that case, we need to + // retrieve the entire attribute value so we can return the correct size. + requestedSize := size + if size == 0 || size > linux.XATTR_SIZE_MAX { + requestedSize = linux.XATTR_SIZE_MAX + } + + value, err := d.Inode.GetXattr(t, name, requestedSize) + if err != nil { + return 0, err + } + n := len(value) + if uint64(n) > requestedSize { + return 0, syserror.ERANGE + } + + // Don't copy out the attribute value if size is 0. + if size == 0 { + return n, nil + } + + if _, err = t.CopyOutBytes(valueAddr, []byte(value)); err != nil { + return 0, err + } + return n, nil +} + +// SetXattr implements linux syscall setxattr(2). +func SetXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return setXattrFromPath(t, args, true) +} + +// LSetXattr implements linux syscall lsetxattr(2). +func LSetXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return setXattrFromPath(t, args, false) +} + +// FSetXattr implements linux syscall fsetxattr(2). +func FSetXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := uint64(args[3].SizeT()) + flags := args[4].Uint() + + // TODO(b/113957122): Return EBADF if the fd was opened with O_PATH. + f := t.GetFile(fd) + if f == nil { + return 0, nil, syserror.EBADF + } + defer f.DecRef(t) + + return 0, nil, setXattr(t, f.Dirent, nameAddr, valueAddr, uint64(size), flags) +} + +func setXattrFromPath(t *kernel.Task, args arch.SyscallArguments, resolveSymlink bool) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := uint64(args[3].SizeT()) + flags := args[4].Uint() + + path, dirPath, err := copyInPath(t, pathAddr, false /* allowEmpty */) + if err != nil { + return 0, nil, err + } + + return 0, nil, fileOpOn(t, linux.AT_FDCWD, path, resolveSymlink, func(_ *fs.Dirent, d *fs.Dirent, _ uint) error { + if dirPath && !fs.IsDir(d.Inode.StableAttr) { + return syserror.ENOTDIR + } + + return setXattr(t, d, nameAddr, valueAddr, uint64(size), flags) + }) +} + +// setXattr implements setxattr(2) from the given *fs.Dirent. +func setXattr(t *kernel.Task, d *fs.Dirent, nameAddr, valueAddr usermem.Addr, size uint64, flags uint32) error { + if flags&^(linux.XATTR_CREATE|linux.XATTR_REPLACE) != 0 { + return syserror.EINVAL + } + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return err + } + + if err := checkXattrPermissions(t, d.Inode, fs.PermMask{Write: true}); err != nil { + return err + } + + if size > linux.XATTR_SIZE_MAX { + return syserror.E2BIG + } + buf := make([]byte, size) + if _, err := t.CopyInBytes(valueAddr, buf); err != nil { + return err + } + value := string(buf) + + if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) { + return syserror.EOPNOTSUPP + } + + if err := d.Inode.SetXattr(t, d, name, value, flags); err != nil { + return err + } + d.InotifyEvent(linux.IN_ATTRIB, 0) + return nil +} + +func copyInXattrName(t *kernel.Task, nameAddr usermem.Addr) (string, error) { + name, err := t.CopyInString(nameAddr, linux.XATTR_NAME_MAX+1) + if err != nil { + if err == syserror.ENAMETOOLONG { + return "", syserror.ERANGE + } + return "", err + } + if len(name) == 0 { + return "", syserror.ERANGE + } + return name, nil +} + +// Restrict xattrs to regular files and directories. +// +// TODO(b/148380782): In Linux, this restriction technically only applies to +// xattrs in the "user.*" namespace. Make file type checks specific to the +// namespace once we allow other xattr prefixes. +func xattrFileTypeOk(i *fs.Inode) bool { + return fs.IsRegular(i.StableAttr) || fs.IsDir(i.StableAttr) +} + +func checkXattrPermissions(t *kernel.Task, i *fs.Inode, perms fs.PermMask) error { + // Restrict xattrs to regular files and directories. + if !xattrFileTypeOk(i) { + if perms.Write { + return syserror.EPERM + } + return syserror.ENODATA + } + + return i.CheckPermission(t, perms) +} + +// ListXattr implements linux syscall listxattr(2). +func ListXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return listXattrFromPath(t, args, true) +} + +// LListXattr implements linux syscall llistxattr(2). +func LListXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return listXattrFromPath(t, args, false) +} + +// FListXattr implements linux syscall flistxattr(2). +func FListXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + listAddr := args[1].Pointer() + size := uint64(args[2].SizeT()) + + // TODO(b/113957122): Return EBADF if the fd was opened with O_PATH. + f := t.GetFile(fd) + if f == nil { + return 0, nil, syserror.EBADF + } + defer f.DecRef(t) + + n, err := listXattr(t, f.Dirent, listAddr, size) + if err != nil { + return 0, nil, err + } + + return uintptr(n), nil, nil +} + +func listXattrFromPath(t *kernel.Task, args arch.SyscallArguments, resolveSymlink bool) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + listAddr := args[1].Pointer() + size := uint64(args[2].SizeT()) + + path, dirPath, err := copyInPath(t, pathAddr, false /* allowEmpty */) + if err != nil { + return 0, nil, err + } + + n := 0 + err = fileOpOn(t, linux.AT_FDCWD, path, resolveSymlink, func(_ *fs.Dirent, d *fs.Dirent, _ uint) error { + if dirPath && !fs.IsDir(d.Inode.StableAttr) { + return syserror.ENOTDIR + } + + n, err = listXattr(t, d, listAddr, size) + return err + }) + if err != nil { + return 0, nil, err + } + + return uintptr(n), nil, nil +} + +func listXattr(t *kernel.Task, d *fs.Dirent, addr usermem.Addr, size uint64) (int, error) { + if !xattrFileTypeOk(d.Inode) { + return 0, nil + } + + // If listxattr(2) is called with size 0, the buffer size needed to contain + // the xattr list will be returned successfully even if it is nonzero. In + // that case, we need to retrieve the entire list so we can compute and + // return the correct size. + requestedSize := size + if size == 0 || size > linux.XATTR_SIZE_MAX { + requestedSize = linux.XATTR_SIZE_MAX + } + xattrs, err := d.Inode.ListXattr(t, requestedSize) + if err != nil { + return 0, err + } + + // TODO(b/148380782): support namespaces other than "user". + for x := range xattrs { + if !strings.HasPrefix(x, linux.XATTR_USER_PREFIX) { + delete(xattrs, x) + } + } + + listSize := xattrListSize(xattrs) + if listSize > linux.XATTR_SIZE_MAX { + return 0, syserror.E2BIG + } + if uint64(listSize) > requestedSize { + return 0, syserror.ERANGE + } + + // Don't copy out the attributes if size is 0. + if size == 0 { + return listSize, nil + } + + buf := make([]byte, 0, listSize) + for x := range xattrs { + buf = append(buf, []byte(x)...) + buf = append(buf, 0) + } + if _, err := t.CopyOutBytes(addr, buf); err != nil { + return 0, err + } + + return len(buf), nil +} + +func xattrListSize(xattrs map[string]struct{}) int { + size := 0 + for x := range xattrs { + size += len(x) + 1 + } + return size +} + +// RemoveXattr implements linux syscall removexattr(2). +func RemoveXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return removeXattrFromPath(t, args, true) +} + +// LRemoveXattr implements linux syscall lremovexattr(2). +func LRemoveXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return removeXattrFromPath(t, args, false) +} + +// FRemoveXattr implements linux syscall fremovexattr(2). +func FRemoveXattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + nameAddr := args[1].Pointer() + + // TODO(b/113957122): Return EBADF if the fd was opened with O_PATH. + f := t.GetFile(fd) + if f == nil { + return 0, nil, syserror.EBADF + } + defer f.DecRef(t) + + return 0, nil, removeXattr(t, f.Dirent, nameAddr) +} + +func removeXattrFromPath(t *kernel.Task, args arch.SyscallArguments, resolveSymlink bool) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + nameAddr := args[1].Pointer() + + path, dirPath, err := copyInPath(t, pathAddr, false /* allowEmpty */) + if err != nil { + return 0, nil, err + } + + return 0, nil, fileOpOn(t, linux.AT_FDCWD, path, resolveSymlink, func(_ *fs.Dirent, d *fs.Dirent, _ uint) error { + if dirPath && !fs.IsDir(d.Inode.StableAttr) { + return syserror.ENOTDIR + } + + return removeXattr(t, d, nameAddr) + }) +} + +// removeXattr implements removexattr(2) from the given *fs.Dirent. +func removeXattr(t *kernel.Task, d *fs.Dirent, nameAddr usermem.Addr) error { + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return err + } + + if err := checkXattrPermissions(t, d.Inode, fs.PermMask{Write: true}); err != nil { + return err + } + + if !strings.HasPrefix(name, linux.XATTR_USER_PREFIX) { + return syserror.EOPNOTSUPP + } + + if err := d.Inode.RemoveXattr(t, d, name); err != nil { + return err + } + d.InotifyEvent(linux.IN_ATTRIB, 0) + return nil +} + +// LINT.ThenChange(vfs2/xattr.go) diff --git a/pkg/sentry/syscalls/linux/timespec.go b/pkg/sentry/syscalls/linux/timespec.go index 4ff8f9234..ddc3ee26e 100644 --- a/pkg/sentry/syscalls/linux/timespec.go +++ b/pkg/sentry/syscalls/linux/timespec.go @@ -19,8 +19,8 @@ import ( "gvisor.dev/gvisor/pkg/abi/linux" "gvisor.dev/gvisor/pkg/sentry/kernel" - "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" ) // copyTimespecIn copies a Timespec from the untrusted app range to the kernel. diff --git a/pkg/sentry/syscalls/linux/vfs2/BUILD b/pkg/sentry/syscalls/linux/vfs2/BUILD new file mode 100644 index 000000000..64696b438 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/BUILD @@ -0,0 +1,78 @@ +load("//tools:defs.bzl", "go_library") + +package(licenses = ["notice"]) + +go_library( + name = "vfs2", + srcs = [ + "aio.go", + "epoll.go", + "eventfd.go", + "execve.go", + "fd.go", + "filesystem.go", + "fscontext.go", + "getdents.go", + "inotify.go", + "ioctl.go", + "lock.go", + "memfd.go", + "mmap.go", + "mount.go", + "path.go", + "pipe.go", + "poll.go", + "read_write.go", + "setstat.go", + "signal.go", + "socket.go", + "splice.go", + "stat.go", + "stat_amd64.go", + "stat_arm64.go", + "sync.go", + "timerfd.go", + "vfs2.go", + "xattr.go", + ], + marshal = True, + visibility = ["//:sandbox"], + deps = [ + "//pkg/abi/linux", + "//pkg/binary", + "//pkg/bits", + "//pkg/context", + "//pkg/fspath", + "//pkg/gohacks", + "//pkg/sentry/arch", + "//pkg/sentry/fs/lock", + "//pkg/sentry/fsbridge", + "//pkg/sentry/fsimpl/eventfd", + "//pkg/sentry/fsimpl/pipefs", + "//pkg/sentry/fsimpl/signalfd", + "//pkg/sentry/fsimpl/timerfd", + "//pkg/sentry/fsimpl/tmpfs", + "//pkg/sentry/kernel", + "//pkg/sentry/kernel/auth", + "//pkg/sentry/kernel/fasync", + "//pkg/sentry/kernel/pipe", + "//pkg/sentry/kernel/time", + "//pkg/sentry/limits", + "//pkg/sentry/loader", + "//pkg/sentry/memmap", + "//pkg/sentry/mm", + "//pkg/sentry/socket", + "//pkg/sentry/socket/control", + "//pkg/sentry/socket/unix/transport", + "//pkg/sentry/syscalls", + "//pkg/sentry/syscalls/linux", + "//pkg/sentry/vfs", + "//pkg/sync", + "//pkg/syserr", + "//pkg/syserror", + "//pkg/usermem", + "//pkg/waiter", + "//tools/go_marshal/marshal", + "//tools/go_marshal/primitive", + ], +) diff --git a/pkg/sentry/syscalls/linux/vfs2/aio.go b/pkg/sentry/syscalls/linux/vfs2/aio.go new file mode 100644 index 000000000..42559bf69 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/aio.go @@ -0,0 +1,219 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/context" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/eventfd" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/mm" + slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// IoSubmit implements linux syscall io_submit(2). +func IoSubmit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + id := args[0].Uint64() + nrEvents := args[1].Int() + addr := args[2].Pointer() + + if nrEvents < 0 { + return 0, nil, syserror.EINVAL + } + + for i := int32(0); i < nrEvents; i++ { + // Copy in the address. + cbAddrNative := t.Arch().Native(0) + if _, err := t.CopyIn(addr, cbAddrNative); err != nil { + if i > 0 { + // Some successful. + return uintptr(i), nil, nil + } + // Nothing done. + return 0, nil, err + } + + // Copy in this callback. + var cb linux.IOCallback + cbAddr := usermem.Addr(t.Arch().Value(cbAddrNative)) + if _, err := t.CopyIn(cbAddr, &cb); err != nil { + if i > 0 { + // Some have been successful. + return uintptr(i), nil, nil + } + // Nothing done. + return 0, nil, err + } + + // Process this callback. + if err := submitCallback(t, id, &cb, cbAddr); err != nil { + if i > 0 { + // Partial success. + return uintptr(i), nil, nil + } + // Nothing done. + return 0, nil, err + } + + // Advance to the next one. + addr += usermem.Addr(t.Arch().Width()) + } + + return uintptr(nrEvents), nil, nil +} + +// submitCallback processes a single callback. +func submitCallback(t *kernel.Task, id uint64, cb *linux.IOCallback, cbAddr usermem.Addr) error { + if cb.Reserved2 != 0 { + return syserror.EINVAL + } + + fd := t.GetFileVFS2(cb.FD) + if fd == nil { + return syserror.EBADF + } + defer fd.DecRef(t) + + // Was there an eventFD? Extract it. + var eventFD *vfs.FileDescription + if cb.Flags&linux.IOCB_FLAG_RESFD != 0 { + eventFD = t.GetFileVFS2(cb.ResFD) + if eventFD == nil { + return syserror.EBADF + } + defer eventFD.DecRef(t) + + // Check that it is an eventfd. + if _, ok := eventFD.Impl().(*eventfd.EventFileDescription); !ok { + return syserror.EINVAL + } + } + + ioseq, err := memoryFor(t, cb) + if err != nil { + return err + } + + // Check offset for reads/writes. + switch cb.OpCode { + case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV: + if cb.Offset < 0 { + return syserror.EINVAL + } + } + + // Prepare the request. + aioCtx, ok := t.MemoryManager().LookupAIOContext(t, id) + if !ok { + return syserror.EINVAL + } + if ready := aioCtx.Prepare(); !ready { + // Context is busy. + return syserror.EAGAIN + } + + if eventFD != nil { + // The request is set. Make sure there's a ref on the file. + // + // This is necessary when the callback executes on completion, + // which is also what will release this reference. + eventFD.IncRef() + } + + // Perform the request asynchronously. + fd.IncRef() + t.QueueAIO(getAIOCallback(t, fd, eventFD, cbAddr, cb, ioseq, aioCtx)) + return nil +} + +func getAIOCallback(t *kernel.Task, fd, eventFD *vfs.FileDescription, cbAddr usermem.Addr, cb *linux.IOCallback, ioseq usermem.IOSequence, aioCtx *mm.AIOContext) kernel.AIOCallback { + return func(ctx context.Context) { + // Release references after completing the callback. + defer fd.DecRef(ctx) + if eventFD != nil { + defer eventFD.DecRef(ctx) + } + + if aioCtx.Dead() { + aioCtx.CancelPendingRequest() + return + } + ev := &linux.IOEvent{ + Data: cb.Data, + Obj: uint64(cbAddr), + } + + var err error + switch cb.OpCode { + case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PREADV: + ev.Result, err = fd.PRead(ctx, ioseq, cb.Offset, vfs.ReadOptions{}) + case linux.IOCB_CMD_PWRITE, linux.IOCB_CMD_PWRITEV: + ev.Result, err = fd.PWrite(ctx, ioseq, cb.Offset, vfs.WriteOptions{}) + case linux.IOCB_CMD_FSYNC, linux.IOCB_CMD_FDSYNC: + err = fd.Sync(ctx) + } + + // Update the result. + if err != nil { + err = slinux.HandleIOErrorVFS2(t, ev.Result != 0 /* partial */, err, nil /* never interrupted */, "aio", fd) + ev.Result = -int64(kernel.ExtractErrno(err, 0)) + } + + // Queue the result for delivery. + aioCtx.FinishRequest(ev) + + // Notify the event file if one was specified. This needs to happen + // *after* queueing the result to avoid racing with the thread we may + // wake up. + if eventFD != nil { + eventFD.Impl().(*eventfd.EventFileDescription).Signal(1) + } + } +} + +// memoryFor returns appropriate memory for the given callback. +func memoryFor(t *kernel.Task, cb *linux.IOCallback) (usermem.IOSequence, error) { + bytes := int(cb.Bytes) + if bytes < 0 { + // Linux also requires that this field fit in ssize_t. + return usermem.IOSequence{}, syserror.EINVAL + } + + // Since this I/O will be asynchronous with respect to t's task goroutine, + // we have no guarantee that t's AddressSpace will be active during the + // I/O. + switch cb.OpCode { + case linux.IOCB_CMD_PREAD, linux.IOCB_CMD_PWRITE: + return t.SingleIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{ + AddressSpaceActive: false, + }) + + case linux.IOCB_CMD_PREADV, linux.IOCB_CMD_PWRITEV: + return t.IovecsIOSequence(usermem.Addr(cb.Buf), bytes, usermem.IOOpts{ + AddressSpaceActive: false, + }) + + case linux.IOCB_CMD_FSYNC, linux.IOCB_CMD_FDSYNC, linux.IOCB_CMD_NOOP: + return usermem.IOSequence{}, nil + + default: + // Not a supported command. + return usermem.IOSequence{}, syserror.EINVAL + } +} diff --git a/pkg/sentry/syscalls/linux/vfs2/epoll.go b/pkg/sentry/syscalls/linux/vfs2/epoll.go new file mode 100644 index 000000000..c62f03509 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/epoll.go @@ -0,0 +1,228 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "math" + "time" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/pkg/waiter" +) + +var sizeofEpollEvent = (*linux.EpollEvent)(nil).SizeBytes() + +// EpollCreate1 implements Linux syscall epoll_create1(2). +func EpollCreate1(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + flags := args[0].Int() + if flags&^linux.EPOLL_CLOEXEC != 0 { + return 0, nil, syserror.EINVAL + } + + file, err := t.Kernel().VFS().NewEpollInstanceFD(t) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + + fd, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{ + CloseOnExec: flags&linux.EPOLL_CLOEXEC != 0, + }) + if err != nil { + return 0, nil, err + } + return uintptr(fd), nil, nil +} + +// EpollCreate implements Linux syscall epoll_create(2). +func EpollCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + size := args[0].Int() + + // "Since Linux 2.6.8, the size argument is ignored, but must be greater + // than zero" - epoll_create(2) + if size <= 0 { + return 0, nil, syserror.EINVAL + } + + file, err := t.Kernel().VFS().NewEpollInstanceFD(t) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + + fd, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{}) + if err != nil { + return 0, nil, err + } + return uintptr(fd), nil, nil +} + +// EpollCtl implements Linux syscall epoll_ctl(2). +func EpollCtl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + epfd := args[0].Int() + op := args[1].Int() + fd := args[2].Int() + eventAddr := args[3].Pointer() + + epfile := t.GetFileVFS2(epfd) + if epfile == nil { + return 0, nil, syserror.EBADF + } + defer epfile.DecRef(t) + ep, ok := epfile.Impl().(*vfs.EpollInstance) + if !ok { + return 0, nil, syserror.EINVAL + } + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + if epfile == file { + return 0, nil, syserror.EINVAL + } + + var event linux.EpollEvent + switch op { + case linux.EPOLL_CTL_ADD: + if _, err := event.CopyIn(t, eventAddr); err != nil { + return 0, nil, err + } + return 0, nil, ep.AddInterest(file, fd, event) + case linux.EPOLL_CTL_DEL: + return 0, nil, ep.DeleteInterest(file, fd) + case linux.EPOLL_CTL_MOD: + if _, err := event.CopyIn(t, eventAddr); err != nil { + return 0, nil, err + } + return 0, nil, ep.ModifyInterest(file, fd, event) + default: + return 0, nil, syserror.EINVAL + } +} + +// EpollWait implements Linux syscall epoll_wait(2). +func EpollWait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + epfd := args[0].Int() + eventsAddr := args[1].Pointer() + maxEvents := int(args[2].Int()) + timeout := int(args[3].Int()) + + var _EP_MAX_EVENTS = math.MaxInt32 / sizeofEpollEvent // Linux: fs/eventpoll.c:EP_MAX_EVENTS + if maxEvents <= 0 || maxEvents > _EP_MAX_EVENTS { + return 0, nil, syserror.EINVAL + } + + epfile := t.GetFileVFS2(epfd) + if epfile == nil { + return 0, nil, syserror.EBADF + } + defer epfile.DecRef(t) + ep, ok := epfile.Impl().(*vfs.EpollInstance) + if !ok { + return 0, nil, syserror.EINVAL + } + + // Use a fixed-size buffer in a loop, instead of make([]linux.EpollEvent, + // maxEvents), so that the buffer can be allocated on the stack. + var ( + events [16]linux.EpollEvent + total int + ch chan struct{} + haveDeadline bool + deadline ktime.Time + ) + for { + batchEvents := len(events) + if batchEvents > maxEvents { + batchEvents = maxEvents + } + n := ep.ReadEvents(events[:batchEvents]) + maxEvents -= n + if n != 0 { + // Copy what we read out. + copiedBytes, err := linux.CopyEpollEventSliceOut(t, eventsAddr, events[:n]) + copiedEvents := copiedBytes / sizeofEpollEvent // rounded down + eventsAddr += usermem.Addr(copiedEvents * sizeofEpollEvent) + total += copiedEvents + if err != nil { + if total != 0 { + return uintptr(total), nil, nil + } + return 0, nil, err + } + // If we've filled the application's event buffer, we're done. + if maxEvents == 0 { + return uintptr(total), nil, nil + } + // Loop if we read a full batch, under the expectation that there + // may be more events to read. + if n == batchEvents { + continue + } + } + // We get here if n != batchEvents. If we read any number of events + // (just now, or in a previous iteration of this loop), or if timeout + // is 0 (such that epoll_wait should be non-blocking), return the + // events we've read so far to the application. + if total != 0 || timeout == 0 { + return uintptr(total), nil, nil + } + // In the first iteration of this loop, register with the epoll + // instance for readability events, but then immediately continue the + // loop since we need to retry ReadEvents() before blocking. In all + // subsequent iterations, block until events are available, the timeout + // expires, or an interrupt arrives. + if ch == nil { + var w waiter.Entry + w, ch = waiter.NewChannelEntry(nil) + epfile.EventRegister(&w, waiter.EventIn) + defer epfile.EventUnregister(&w) + } else { + // Set up the timer if a timeout was specified. + if timeout > 0 && !haveDeadline { + timeoutDur := time.Duration(timeout) * time.Millisecond + deadline = t.Kernel().MonotonicClock().Now().Add(timeoutDur) + haveDeadline = true + } + if err := t.BlockWithDeadline(ch, haveDeadline, deadline); err != nil { + if err == syserror.ETIMEDOUT { + err = nil + } + // total must be 0 since otherwise we would have returned + // above. + return 0, nil, err + } + } + } +} + +// EpollPwait implements Linux syscall epoll_pwait(2). +func EpollPwait(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + maskAddr := args[4].Pointer() + maskSize := uint(args[5].Uint()) + + if err := setTempSignalSet(t, maskAddr, maskSize); err != nil { + return 0, nil, err + } + + return EpollWait(t, args) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/eventfd.go b/pkg/sentry/syscalls/linux/vfs2/eventfd.go new file mode 100644 index 000000000..807f909da --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/eventfd.go @@ -0,0 +1,61 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/eventfd" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Eventfd2 implements linux syscall eventfd2(2). +func Eventfd2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + initVal := uint64(args[0].Uint()) + flags := uint(args[1].Uint()) + allOps := uint(linux.EFD_SEMAPHORE | linux.EFD_NONBLOCK | linux.EFD_CLOEXEC) + + if flags & ^allOps != 0 { + return 0, nil, syserror.EINVAL + } + + vfsObj := t.Kernel().VFS() + fileFlags := uint32(linux.O_RDWR) + if flags&linux.EFD_NONBLOCK != 0 { + fileFlags |= linux.O_NONBLOCK + } + semMode := flags&linux.EFD_SEMAPHORE != 0 + eventfd, err := eventfd.New(t, vfsObj, initVal, semMode, fileFlags) + if err != nil { + return 0, nil, err + } + defer eventfd.DecRef(t) + + fd, err := t.NewFDFromVFS2(0, eventfd, kernel.FDFlags{ + CloseOnExec: flags&linux.EFD_CLOEXEC != 0, + }) + if err != nil { + return 0, nil, err + } + + return uintptr(fd), nil, nil +} + +// Eventfd implements linux syscall eventfd(2). +func Eventfd(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + args[1].Value = 0 + return Eventfd2(t, args) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/execve.go b/pkg/sentry/syscalls/linux/vfs2/execve.go new file mode 100644 index 000000000..066ee0863 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/execve.go @@ -0,0 +1,137 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsbridge" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/loader" + slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Execve implements linux syscall execve(2). +func Execve(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathnameAddr := args[0].Pointer() + argvAddr := args[1].Pointer() + envvAddr := args[2].Pointer() + return execveat(t, linux.AT_FDCWD, pathnameAddr, argvAddr, envvAddr, 0 /* flags */) +} + +// Execveat implements linux syscall execveat(2). +func Execveat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathnameAddr := args[1].Pointer() + argvAddr := args[2].Pointer() + envvAddr := args[3].Pointer() + flags := args[4].Int() + return execveat(t, dirfd, pathnameAddr, argvAddr, envvAddr, flags) +} + +func execveat(t *kernel.Task, dirfd int32, pathnameAddr, argvAddr, envvAddr usermem.Addr, flags int32) (uintptr, *kernel.SyscallControl, error) { + if flags&^(linux.AT_EMPTY_PATH|linux.AT_SYMLINK_NOFOLLOW) != 0 { + return 0, nil, syserror.EINVAL + } + + pathname, err := t.CopyInString(pathnameAddr, linux.PATH_MAX) + if err != nil { + return 0, nil, err + } + var argv, envv []string + if argvAddr != 0 { + var err error + argv, err = t.CopyInVector(argvAddr, slinux.ExecMaxElemSize, slinux.ExecMaxTotalSize) + if err != nil { + return 0, nil, err + } + } + if envvAddr != 0 { + var err error + envv, err = t.CopyInVector(envvAddr, slinux.ExecMaxElemSize, slinux.ExecMaxTotalSize) + if err != nil { + return 0, nil, err + } + } + + root := t.FSContext().RootDirectoryVFS2() + defer root.DecRef(t) + var executable fsbridge.File + closeOnExec := false + if path := fspath.Parse(pathname); dirfd != linux.AT_FDCWD && !path.Absolute { + // We must open the executable ourselves since dirfd is used as the + // starting point while resolving path, but the task working directory + // is used as the starting point while resolving interpreters (Linux: + // fs/binfmt_script.c:load_script() => fs/exec.c:open_exec() => + // do_open_execat(fd=AT_FDCWD)), and the loader package is currently + // incapable of handling this correctly. + if !path.HasComponents() && flags&linux.AT_EMPTY_PATH == 0 { + return 0, nil, syserror.ENOENT + } + dirfile, dirfileFlags := t.FDTable().GetVFS2(dirfd) + if dirfile == nil { + return 0, nil, syserror.EBADF + } + start := dirfile.VirtualDentry() + start.IncRef() + dirfile.DecRef(t) + closeOnExec = dirfileFlags.CloseOnExec + file, err := t.Kernel().VFS().OpenAt(t, t.Credentials(), &vfs.PathOperation{ + Root: root, + Start: start, + Path: path, + FollowFinalSymlink: flags&linux.AT_SYMLINK_NOFOLLOW == 0, + }, &vfs.OpenOptions{ + Flags: linux.O_RDONLY, + FileExec: true, + }) + start.DecRef(t) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + executable = fsbridge.NewVFSFile(file) + } + + // Load the new TaskContext. + mntns := t.MountNamespaceVFS2() // FIXME(jamieliu): useless refcount change + defer mntns.DecRef(t) + wd := t.FSContext().WorkingDirectoryVFS2() + defer wd.DecRef(t) + remainingTraversals := uint(linux.MaxSymlinkTraversals) + loadArgs := loader.LoadArgs{ + Opener: fsbridge.NewVFSLookup(mntns, root, wd), + RemainingTraversals: &remainingTraversals, + ResolveFinal: flags&linux.AT_SYMLINK_NOFOLLOW == 0, + Filename: pathname, + File: executable, + CloseOnExec: closeOnExec, + Argv: argv, + Envv: envv, + Features: t.Arch().FeatureSet(), + } + + tc, se := t.Kernel().LoadTaskImage(t, loadArgs) + if se != nil { + return 0, nil, se.ToError() + } + + ctrl, err := t.Execve(tc) + return 0, ctrl, err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/fd.go b/pkg/sentry/syscalls/linux/vfs2/fd.go new file mode 100644 index 000000000..4856554fe --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/fd.go @@ -0,0 +1,355 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fs/lock" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/fasync" + "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" + slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Close implements Linux syscall close(2). +func Close(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + + // Note that Remove provides a reference on the file that we may use to + // flush. It is still active until we drop the final reference below + // (and other reference-holding operations complete). + _, file := t.FDTable().Remove(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + err := file.OnClose(t) + return 0, nil, slinux.HandleIOErrorVFS2(t, false /* partial */, err, syserror.EINTR, "close", file) +} + +// Dup implements Linux syscall dup(2). +func Dup(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + newFD, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{}) + if err != nil { + return 0, nil, syserror.EMFILE + } + return uintptr(newFD), nil, nil +} + +// Dup2 implements Linux syscall dup2(2). +func Dup2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + oldfd := args[0].Int() + newfd := args[1].Int() + + if oldfd == newfd { + // As long as oldfd is valid, dup2() does nothing and returns newfd. + file := t.GetFileVFS2(oldfd) + if file == nil { + return 0, nil, syserror.EBADF + } + file.DecRef(t) + return uintptr(newfd), nil, nil + } + + return dup3(t, oldfd, newfd, 0) +} + +// Dup3 implements Linux syscall dup3(2). +func Dup3(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + oldfd := args[0].Int() + newfd := args[1].Int() + flags := args[2].Uint() + + if oldfd == newfd { + return 0, nil, syserror.EINVAL + } + + return dup3(t, oldfd, newfd, flags) +} + +func dup3(t *kernel.Task, oldfd, newfd int32, flags uint32) (uintptr, *kernel.SyscallControl, error) { + if flags&^linux.O_CLOEXEC != 0 { + return 0, nil, syserror.EINVAL + } + + file := t.GetFileVFS2(oldfd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + err := t.NewFDAtVFS2(newfd, file, kernel.FDFlags{ + CloseOnExec: flags&linux.O_CLOEXEC != 0, + }) + if err != nil { + return 0, nil, err + } + return uintptr(newfd), nil, nil +} + +// Fcntl implements linux syscall fcntl(2). +func Fcntl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + cmd := args[1].Int() + + file, flags := t.FDTable().GetVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + switch cmd { + case linux.F_DUPFD, linux.F_DUPFD_CLOEXEC: + minfd := args[2].Int() + fd, err := t.NewFDFromVFS2(minfd, file, kernel.FDFlags{ + CloseOnExec: cmd == linux.F_DUPFD_CLOEXEC, + }) + if err != nil { + return 0, nil, err + } + return uintptr(fd), nil, nil + case linux.F_GETFD: + return uintptr(flags.ToLinuxFDFlags()), nil, nil + case linux.F_SETFD: + flags := args[2].Uint() + err := t.FDTable().SetFlagsVFS2(fd, kernel.FDFlags{ + CloseOnExec: flags&linux.FD_CLOEXEC != 0, + }) + return 0, nil, err + case linux.F_GETFL: + return uintptr(file.StatusFlags()), nil, nil + case linux.F_SETFL: + return 0, nil, file.SetStatusFlags(t, t.Credentials(), args[2].Uint()) + case linux.F_SETPIPE_SZ: + pipefile, ok := file.Impl().(*pipe.VFSPipeFD) + if !ok { + return 0, nil, syserror.EBADF + } + n, err := pipefile.SetPipeSize(int64(args[2].Int())) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil + case linux.F_GETOWN: + owner, hasOwner := getAsyncOwner(t, file) + if !hasOwner { + return 0, nil, nil + } + if owner.Type == linux.F_OWNER_PGRP { + return uintptr(-owner.PID), nil, nil + } + return uintptr(owner.PID), nil, nil + case linux.F_SETOWN: + who := args[2].Int() + ownerType := int32(linux.F_OWNER_PID) + if who < 0 { + // Check for overflow before flipping the sign. + if who-1 > who { + return 0, nil, syserror.EINVAL + } + ownerType = linux.F_OWNER_PGRP + who = -who + } + return 0, nil, setAsyncOwner(t, file, ownerType, who) + case linux.F_GETOWN_EX: + owner, hasOwner := getAsyncOwner(t, file) + if !hasOwner { + return 0, nil, nil + } + _, err := t.CopyOut(args[2].Pointer(), &owner) + return 0, nil, err + case linux.F_SETOWN_EX: + var owner linux.FOwnerEx + _, err := t.CopyIn(args[2].Pointer(), &owner) + if err != nil { + return 0, nil, err + } + return 0, nil, setAsyncOwner(t, file, owner.Type, owner.PID) + case linux.F_GETPIPE_SZ: + pipefile, ok := file.Impl().(*pipe.VFSPipeFD) + if !ok { + return 0, nil, syserror.EBADF + } + return uintptr(pipefile.PipeSize()), nil, nil + case linux.F_GET_SEALS: + val, err := tmpfs.GetSeals(file) + return uintptr(val), nil, err + case linux.F_ADD_SEALS: + if !file.IsWritable() { + return 0, nil, syserror.EPERM + } + err := tmpfs.AddSeals(file, args[2].Uint()) + return 0, nil, err + case linux.F_SETLK, linux.F_SETLKW: + return 0, nil, posixLock(t, args, file, cmd) + default: + // Everything else is not yet supported. + return 0, nil, syserror.EINVAL + } +} + +func getAsyncOwner(t *kernel.Task, fd *vfs.FileDescription) (ownerEx linux.FOwnerEx, hasOwner bool) { + a := fd.AsyncHandler() + if a == nil { + return linux.FOwnerEx{}, false + } + + ot, otg, opg := a.(*fasync.FileAsync).Owner() + switch { + case ot != nil: + return linux.FOwnerEx{ + Type: linux.F_OWNER_TID, + PID: int32(t.PIDNamespace().IDOfTask(ot)), + }, true + case otg != nil: + return linux.FOwnerEx{ + Type: linux.F_OWNER_PID, + PID: int32(t.PIDNamespace().IDOfThreadGroup(otg)), + }, true + case opg != nil: + return linux.FOwnerEx{ + Type: linux.F_OWNER_PGRP, + PID: int32(t.PIDNamespace().IDOfProcessGroup(opg)), + }, true + default: + return linux.FOwnerEx{}, true + } +} + +func setAsyncOwner(t *kernel.Task, fd *vfs.FileDescription, ownerType, pid int32) error { + switch ownerType { + case linux.F_OWNER_TID, linux.F_OWNER_PID, linux.F_OWNER_PGRP: + // Acceptable type. + default: + return syserror.EINVAL + } + + a := fd.SetAsyncHandler(fasync.NewVFS2).(*fasync.FileAsync) + if pid == 0 { + a.ClearOwner() + return nil + } + + switch ownerType { + case linux.F_OWNER_TID: + task := t.PIDNamespace().TaskWithID(kernel.ThreadID(pid)) + if task == nil { + return syserror.ESRCH + } + a.SetOwnerTask(t, task) + return nil + case linux.F_OWNER_PID: + tg := t.PIDNamespace().ThreadGroupWithID(kernel.ThreadID(pid)) + if tg == nil { + return syserror.ESRCH + } + a.SetOwnerThreadGroup(t, tg) + return nil + case linux.F_OWNER_PGRP: + pg := t.PIDNamespace().ProcessGroupWithID(kernel.ProcessGroupID(pid)) + if pg == nil { + return syserror.ESRCH + } + a.SetOwnerProcessGroup(t, pg) + return nil + default: + return syserror.EINVAL + } +} + +func posixLock(t *kernel.Task, args arch.SyscallArguments, file *vfs.FileDescription, cmd int32) error { + // Copy in the lock request. + flockAddr := args[2].Pointer() + var flock linux.Flock + if _, err := t.CopyIn(flockAddr, &flock); err != nil { + return err + } + + var blocker lock.Blocker + if cmd == linux.F_SETLKW { + blocker = t + } + + switch flock.Type { + case linux.F_RDLCK: + if !file.IsReadable() { + return syserror.EBADF + } + return file.LockPOSIX(t, t.FDTable(), lock.ReadLock, uint64(flock.Start), uint64(flock.Len), flock.Whence, blocker) + + case linux.F_WRLCK: + if !file.IsWritable() { + return syserror.EBADF + } + return file.LockPOSIX(t, t.FDTable(), lock.WriteLock, uint64(flock.Start), uint64(flock.Len), flock.Whence, blocker) + + case linux.F_UNLCK: + return file.UnlockPOSIX(t, t.FDTable(), uint64(flock.Start), uint64(flock.Len), flock.Whence) + + default: + return syserror.EINVAL + } +} + +// Fadvise64 implements fadvise64(2). +// This implementation currently ignores the provided advice. +func Fadvise64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + length := args[2].Int64() + advice := args[3].Int() + + // Note: offset is allowed to be negative. + if length < 0 { + return 0, nil, syserror.EINVAL + } + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // If the FD refers to a pipe or FIFO, return error. + if _, isPipe := file.Impl().(*pipe.VFSPipeFD); isPipe { + return 0, nil, syserror.ESPIPE + } + + switch advice { + case linux.POSIX_FADV_NORMAL: + case linux.POSIX_FADV_RANDOM: + case linux.POSIX_FADV_SEQUENTIAL: + case linux.POSIX_FADV_WILLNEED: + case linux.POSIX_FADV_DONTNEED: + case linux.POSIX_FADV_NOREUSE: + default: + return 0, nil, syserror.EINVAL + } + + // Sure, whatever. + return 0, nil, nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/filesystem.go b/pkg/sentry/syscalls/linux/vfs2/filesystem.go new file mode 100644 index 000000000..01e0f9010 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/filesystem.go @@ -0,0 +1,334 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Link implements Linux syscall link(2). +func Link(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + oldpathAddr := args[0].Pointer() + newpathAddr := args[1].Pointer() + return 0, nil, linkat(t, linux.AT_FDCWD, oldpathAddr, linux.AT_FDCWD, newpathAddr, 0 /* flags */) +} + +// Linkat implements Linux syscall linkat(2). +func Linkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + olddirfd := args[0].Int() + oldpathAddr := args[1].Pointer() + newdirfd := args[2].Int() + newpathAddr := args[3].Pointer() + flags := args[4].Int() + return 0, nil, linkat(t, olddirfd, oldpathAddr, newdirfd, newpathAddr, flags) +} + +func linkat(t *kernel.Task, olddirfd int32, oldpathAddr usermem.Addr, newdirfd int32, newpathAddr usermem.Addr, flags int32) error { + if flags&^(linux.AT_EMPTY_PATH|linux.AT_SYMLINK_FOLLOW) != 0 { + return syserror.EINVAL + } + if flags&linux.AT_EMPTY_PATH != 0 && !t.HasCapability(linux.CAP_DAC_READ_SEARCH) { + return syserror.ENOENT + } + + oldpath, err := copyInPath(t, oldpathAddr) + if err != nil { + return err + } + oldtpop, err := getTaskPathOperation(t, olddirfd, oldpath, shouldAllowEmptyPath(flags&linux.AT_EMPTY_PATH != 0), shouldFollowFinalSymlink(flags&linux.AT_SYMLINK_FOLLOW != 0)) + if err != nil { + return err + } + defer oldtpop.Release(t) + + newpath, err := copyInPath(t, newpathAddr) + if err != nil { + return err + } + newtpop, err := getTaskPathOperation(t, newdirfd, newpath, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer newtpop.Release(t) + + return t.Kernel().VFS().LinkAt(t, t.Credentials(), &oldtpop.pop, &newtpop.pop) +} + +// Mkdir implements Linux syscall mkdir(2). +func Mkdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + mode := args[1].ModeT() + return 0, nil, mkdirat(t, linux.AT_FDCWD, addr, mode) +} + +// Mkdirat implements Linux syscall mkdirat(2). +func Mkdirat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + addr := args[1].Pointer() + mode := args[2].ModeT() + return 0, nil, mkdirat(t, dirfd, addr, mode) +} + +func mkdirat(t *kernel.Task, dirfd int32, addr usermem.Addr, mode uint) error { + path, err := copyInPath(t, addr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + return t.Kernel().VFS().MkdirAt(t, t.Credentials(), &tpop.pop, &vfs.MkdirOptions{ + Mode: linux.FileMode(mode & (0777 | linux.S_ISVTX) &^ t.FSContext().Umask()), + }) +} + +// Mknod implements Linux syscall mknod(2). +func Mknod(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + mode := args[1].ModeT() + dev := args[2].Uint() + return 0, nil, mknodat(t, linux.AT_FDCWD, addr, linux.FileMode(mode), dev) +} + +// Mknodat implements Linux syscall mknodat(2). +func Mknodat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + addr := args[1].Pointer() + mode := args[2].ModeT() + dev := args[3].Uint() + return 0, nil, mknodat(t, dirfd, addr, linux.FileMode(mode), dev) +} + +func mknodat(t *kernel.Task, dirfd int32, addr usermem.Addr, mode linux.FileMode, dev uint32) error { + path, err := copyInPath(t, addr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + + // "Zero file type is equivalent to type S_IFREG." - mknod(2) + if mode.FileType() == 0 { + mode |= linux.ModeRegular + } + major, minor := linux.DecodeDeviceID(dev) + return t.Kernel().VFS().MknodAt(t, t.Credentials(), &tpop.pop, &vfs.MknodOptions{ + Mode: mode &^ linux.FileMode(t.FSContext().Umask()), + DevMajor: uint32(major), + DevMinor: minor, + }) +} + +// Open implements Linux syscall open(2). +func Open(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + flags := args[1].Uint() + mode := args[2].ModeT() + return openat(t, linux.AT_FDCWD, addr, flags, mode) +} + +// Openat implements Linux syscall openat(2). +func Openat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + addr := args[1].Pointer() + flags := args[2].Uint() + mode := args[3].ModeT() + return openat(t, dirfd, addr, flags, mode) +} + +// Creat implements Linux syscall creat(2). +func Creat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + mode := args[1].ModeT() + return openat(t, linux.AT_FDCWD, addr, linux.O_WRONLY|linux.O_CREAT|linux.O_TRUNC, mode) +} + +func openat(t *kernel.Task, dirfd int32, pathAddr usermem.Addr, flags uint32, mode uint) (uintptr, *kernel.SyscallControl, error) { + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, shouldFollowFinalSymlink(flags&linux.O_NOFOLLOW == 0)) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + file, err := t.Kernel().VFS().OpenAt(t, t.Credentials(), &tpop.pop, &vfs.OpenOptions{ + Flags: flags | linux.O_LARGEFILE, + Mode: linux.FileMode(mode & (0777 | linux.S_ISUID | linux.S_ISGID | linux.S_ISVTX) &^ t.FSContext().Umask()), + }) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + + fd, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{ + CloseOnExec: flags&linux.O_CLOEXEC != 0, + }) + return uintptr(fd), nil, err +} + +// Rename implements Linux syscall rename(2). +func Rename(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + oldpathAddr := args[0].Pointer() + newpathAddr := args[1].Pointer() + return 0, nil, renameat(t, linux.AT_FDCWD, oldpathAddr, linux.AT_FDCWD, newpathAddr, 0 /* flags */) +} + +// Renameat implements Linux syscall renameat(2). +func Renameat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + olddirfd := args[0].Int() + oldpathAddr := args[1].Pointer() + newdirfd := args[2].Int() + newpathAddr := args[3].Pointer() + return 0, nil, renameat(t, olddirfd, oldpathAddr, newdirfd, newpathAddr, 0 /* flags */) +} + +// Renameat2 implements Linux syscall renameat2(2). +func Renameat2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + olddirfd := args[0].Int() + oldpathAddr := args[1].Pointer() + newdirfd := args[2].Int() + newpathAddr := args[3].Pointer() + flags := args[4].Uint() + return 0, nil, renameat(t, olddirfd, oldpathAddr, newdirfd, newpathAddr, flags) +} + +func renameat(t *kernel.Task, olddirfd int32, oldpathAddr usermem.Addr, newdirfd int32, newpathAddr usermem.Addr, flags uint32) error { + oldpath, err := copyInPath(t, oldpathAddr) + if err != nil { + return err + } + // "If oldpath refers to a symbolic link, the link is renamed" - rename(2) + oldtpop, err := getTaskPathOperation(t, olddirfd, oldpath, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer oldtpop.Release(t) + + newpath, err := copyInPath(t, newpathAddr) + if err != nil { + return err + } + newtpop, err := getTaskPathOperation(t, newdirfd, newpath, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer newtpop.Release(t) + + return t.Kernel().VFS().RenameAt(t, t.Credentials(), &oldtpop.pop, &newtpop.pop, &vfs.RenameOptions{ + Flags: flags, + }) +} + +// Rmdir implements Linux syscall rmdir(2). +func Rmdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + return 0, nil, rmdirat(t, linux.AT_FDCWD, pathAddr) +} + +func rmdirat(t *kernel.Task, dirfd int32, pathAddr usermem.Addr) error { + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + return t.Kernel().VFS().RmdirAt(t, t.Credentials(), &tpop.pop) +} + +// Unlink implements Linux syscall unlink(2). +func Unlink(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + return 0, nil, unlinkat(t, linux.AT_FDCWD, pathAddr) +} + +func unlinkat(t *kernel.Task, dirfd int32, pathAddr usermem.Addr) error { + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + return t.Kernel().VFS().UnlinkAt(t, t.Credentials(), &tpop.pop) +} + +// Unlinkat implements Linux syscall unlinkat(2). +func Unlinkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + flags := args[2].Int() + + if flags&^linux.AT_REMOVEDIR != 0 { + return 0, nil, syserror.EINVAL + } + + if flags&linux.AT_REMOVEDIR != 0 { + return 0, nil, rmdirat(t, dirfd, pathAddr) + } + return 0, nil, unlinkat(t, dirfd, pathAddr) +} + +// Symlink implements Linux syscall symlink(2). +func Symlink(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + targetAddr := args[0].Pointer() + linkpathAddr := args[1].Pointer() + return 0, nil, symlinkat(t, targetAddr, linux.AT_FDCWD, linkpathAddr) +} + +// Symlinkat implements Linux syscall symlinkat(2). +func Symlinkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + targetAddr := args[0].Pointer() + newdirfd := args[1].Int() + linkpathAddr := args[2].Pointer() + return 0, nil, symlinkat(t, targetAddr, newdirfd, linkpathAddr) +} + +func symlinkat(t *kernel.Task, targetAddr usermem.Addr, newdirfd int32, linkpathAddr usermem.Addr) error { + target, err := t.CopyInString(targetAddr, linux.PATH_MAX) + if err != nil { + return err + } + if len(target) == 0 { + return syserror.ENOENT + } + linkpath, err := copyInPath(t, linkpathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, newdirfd, linkpath, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + return t.Kernel().VFS().SymlinkAt(t, t.Credentials(), &tpop.pop, target) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/fscontext.go b/pkg/sentry/syscalls/linux/vfs2/fscontext.go new file mode 100644 index 000000000..a7d4d2a36 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/fscontext.go @@ -0,0 +1,131 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Getcwd implements Linux syscall getcwd(2). +func Getcwd(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + size := args[1].SizeT() + + root := t.FSContext().RootDirectoryVFS2() + wd := t.FSContext().WorkingDirectoryVFS2() + s, err := t.Kernel().VFS().PathnameForGetcwd(t, root, wd) + root.DecRef(t) + wd.DecRef(t) + if err != nil { + return 0, nil, err + } + + // Note this is >= because we need a terminator. + if uint(len(s)) >= size { + return 0, nil, syserror.ERANGE + } + + // Construct a byte slice containing a NUL terminator. + buf := t.CopyScratchBuffer(len(s) + 1) + copy(buf, s) + buf[len(buf)-1] = 0 + + // Write the pathname slice. + n, err := t.CopyOutBytes(addr, buf) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +// Chdir implements Linux syscall chdir(2). +func Chdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + + path, err := copyInPath(t, addr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + vd, err := t.Kernel().VFS().GetDentryAt(t, t.Credentials(), &tpop.pop, &vfs.GetDentryOptions{ + CheckSearchable: true, + }) + if err != nil { + return 0, nil, err + } + t.FSContext().SetWorkingDirectoryVFS2(t, vd) + vd.DecRef(t) + return 0, nil, nil +} + +// Fchdir implements Linux syscall fchdir(2). +func Fchdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + + tpop, err := getTaskPathOperation(t, fd, fspath.Path{}, allowEmptyPath, nofollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + vd, err := t.Kernel().VFS().GetDentryAt(t, t.Credentials(), &tpop.pop, &vfs.GetDentryOptions{ + CheckSearchable: true, + }) + if err != nil { + return 0, nil, err + } + t.FSContext().SetWorkingDirectoryVFS2(t, vd) + vd.DecRef(t) + return 0, nil, nil +} + +// Chroot implements Linux syscall chroot(2). +func Chroot(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + + if !t.HasCapability(linux.CAP_SYS_CHROOT) { + return 0, nil, syserror.EPERM + } + + path, err := copyInPath(t, addr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + vd, err := t.Kernel().VFS().GetDentryAt(t, t.Credentials(), &tpop.pop, &vfs.GetDentryOptions{ + CheckSearchable: true, + }) + if err != nil { + return 0, nil, err + } + t.FSContext().SetRootDirectoryVFS2(t, vd) + vd.DecRef(t) + return 0, nil, nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/getdents.go b/pkg/sentry/syscalls/linux/vfs2/getdents.go new file mode 100644 index 000000000..5517595b5 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/getdents.go @@ -0,0 +1,161 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "fmt" + + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/sync" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Getdents implements Linux syscall getdents(2). +func Getdents(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return getdents(t, args, false /* isGetdents64 */) +} + +// Getdents64 implements Linux syscall getdents64(2). +func Getdents64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return getdents(t, args, true /* isGetdents64 */) +} + +func getdents(t *kernel.Task, args arch.SyscallArguments, isGetdents64 bool) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + size := int(args[2].Uint()) + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + cb := getGetdentsCallback(t, addr, size, isGetdents64) + err := file.IterDirents(t, cb) + n := size - cb.remaining + putGetdentsCallback(cb) + if n == 0 { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +type getdentsCallback struct { + t *kernel.Task + addr usermem.Addr + remaining int + isGetdents64 bool +} + +var getdentsCallbackPool = sync.Pool{ + New: func() interface{} { + return &getdentsCallback{} + }, +} + +func getGetdentsCallback(t *kernel.Task, addr usermem.Addr, size int, isGetdents64 bool) *getdentsCallback { + cb := getdentsCallbackPool.Get().(*getdentsCallback) + *cb = getdentsCallback{ + t: t, + addr: addr, + remaining: size, + isGetdents64: isGetdents64, + } + return cb +} + +func putGetdentsCallback(cb *getdentsCallback) { + cb.t = nil + getdentsCallbackPool.Put(cb) +} + +// Handle implements vfs.IterDirentsCallback.Handle. +func (cb *getdentsCallback) Handle(dirent vfs.Dirent) error { + var buf []byte + if cb.isGetdents64 { + // struct linux_dirent64 { + // ino64_t d_ino; /* 64-bit inode number */ + // off64_t d_off; /* 64-bit offset to next structure */ + // unsigned short d_reclen; /* Size of this dirent */ + // unsigned char d_type; /* File type */ + // char d_name[]; /* Filename (null-terminated) */ + // }; + size := 8 + 8 + 2 + 1 + 1 + len(dirent.Name) + size = (size + 7) &^ 7 // round up to multiple of 8 + if size > cb.remaining { + return syserror.EINVAL + } + buf = cb.t.CopyScratchBuffer(size) + usermem.ByteOrder.PutUint64(buf[0:8], dirent.Ino) + usermem.ByteOrder.PutUint64(buf[8:16], uint64(dirent.NextOff)) + usermem.ByteOrder.PutUint16(buf[16:18], uint16(size)) + buf[18] = dirent.Type + copy(buf[19:], dirent.Name) + // Zero out all remaining bytes in buf, including the NUL terminator + // after dirent.Name. + bufTail := buf[19+len(dirent.Name):] + for i := range bufTail { + bufTail[i] = 0 + } + } else { + // struct linux_dirent { + // unsigned long d_ino; /* Inode number */ + // unsigned long d_off; /* Offset to next linux_dirent */ + // unsigned short d_reclen; /* Length of this linux_dirent */ + // char d_name[]; /* Filename (null-terminated) */ + // /* length is actually (d_reclen - 2 - + // offsetof(struct linux_dirent, d_name)) */ + // /* + // char pad; // Zero padding byte + // char d_type; // File type (only since Linux + // // 2.6.4); offset is (d_reclen - 1) + // */ + // }; + if cb.t.Arch().Width() != 8 { + panic(fmt.Sprintf("unsupported sizeof(unsigned long): %d", cb.t.Arch().Width())) + } + size := 8 + 8 + 2 + 1 + 1 + len(dirent.Name) + size = (size + 7) &^ 7 // round up to multiple of sizeof(long) + if size > cb.remaining { + return syserror.EINVAL + } + buf = cb.t.CopyScratchBuffer(size) + usermem.ByteOrder.PutUint64(buf[0:8], dirent.Ino) + usermem.ByteOrder.PutUint64(buf[8:16], uint64(dirent.NextOff)) + usermem.ByteOrder.PutUint16(buf[16:18], uint16(size)) + copy(buf[18:], dirent.Name) + // Zero out all remaining bytes in buf, including the NUL terminator + // after dirent.Name and the zero padding byte between the name and + // dirent type. + bufTail := buf[18+len(dirent.Name) : size-1] + for i := range bufTail { + bufTail[i] = 0 + } + buf[size-1] = dirent.Type + } + n, err := cb.t.CopyOutBytes(cb.addr, buf) + if err != nil { + // Don't report partially-written dirents by advancing cb.addr or + // cb.remaining. + return err + } + cb.addr += usermem.Addr(n) + cb.remaining -= n + return nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/inotify.go b/pkg/sentry/syscalls/linux/vfs2/inotify.go new file mode 100644 index 000000000..11753d8e5 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/inotify.go @@ -0,0 +1,137 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" +) + +const allFlags = linux.IN_NONBLOCK | linux.IN_CLOEXEC + +// InotifyInit1 implements the inotify_init1() syscalls. +func InotifyInit1(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + flags := args[0].Int() + if flags&^allFlags != 0 { + return 0, nil, syserror.EINVAL + } + + ino, err := vfs.NewInotifyFD(t, t.Kernel().VFS(), uint32(flags)) + if err != nil { + return 0, nil, err + } + defer ino.DecRef(t) + + fd, err := t.NewFDFromVFS2(0, ino, kernel.FDFlags{ + CloseOnExec: flags&linux.IN_CLOEXEC != 0, + }) + + if err != nil { + return 0, nil, err + } + + return uintptr(fd), nil, nil +} + +// InotifyInit implements the inotify_init() syscalls. +func InotifyInit(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + args[0].Value = 0 + return InotifyInit1(t, args) +} + +// fdToInotify resolves an fd to an inotify object. If successful, the file will +// have an extra ref and the caller is responsible for releasing the ref. +func fdToInotify(t *kernel.Task, fd int32) (*vfs.Inotify, *vfs.FileDescription, error) { + f := t.GetFileVFS2(fd) + if f == nil { + // Invalid fd. + return nil, nil, syserror.EBADF + } + + ino, ok := f.Impl().(*vfs.Inotify) + if !ok { + // Not an inotify fd. + f.DecRef(t) + return nil, nil, syserror.EINVAL + } + + return ino, f, nil +} + +// InotifyAddWatch implements the inotify_add_watch() syscall. +func InotifyAddWatch(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + mask := args[2].Uint() + + // "EINVAL: The given event mask contains no valid events." + // -- inotify_add_watch(2) + if mask&linux.ALL_INOTIFY_BITS == 0 { + return 0, nil, syserror.EINVAL + } + + // "IN_DONT_FOLLOW: Don't dereference pathname if it is a symbolic link." + // -- inotify(7) + follow := followFinalSymlink + if mask&linux.IN_DONT_FOLLOW == 0 { + follow = nofollowFinalSymlink + } + + ino, f, err := fdToInotify(t, fd) + if err != nil { + return 0, nil, err + } + defer f.DecRef(t) + + path, err := copyInPath(t, addr) + if err != nil { + return 0, nil, err + } + if mask&linux.IN_ONLYDIR != 0 { + path.Dir = true + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, follow) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + d, err := t.Kernel().VFS().GetDentryAt(t, t.Credentials(), &tpop.pop, &vfs.GetDentryOptions{}) + if err != nil { + return 0, nil, err + } + defer d.DecRef(t) + + fd, err = ino.AddWatch(d.Dentry(), mask) + if err != nil { + return 0, nil, err + } + return uintptr(fd), nil, nil +} + +// InotifyRmWatch implements the inotify_rm_watch() syscall. +func InotifyRmWatch(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + wd := args[1].Int() + + ino, f, err := fdToInotify(t, fd) + if err != nil { + return 0, nil, err + } + defer f.DecRef(t) + return 0, nil, ino.RmWatch(t, wd) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/ioctl.go b/pkg/sentry/syscalls/linux/vfs2/ioctl.go new file mode 100644 index 000000000..38778a388 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/ioctl.go @@ -0,0 +1,107 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Ioctl implements Linux syscall ioctl(2). +func Ioctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Handle ioctls that apply to all FDs. + switch args[1].Int() { + case linux.FIONCLEX: + t.FDTable().SetFlagsVFS2(fd, kernel.FDFlags{ + CloseOnExec: false, + }) + return 0, nil, nil + + case linux.FIOCLEX: + t.FDTable().SetFlagsVFS2(fd, kernel.FDFlags{ + CloseOnExec: true, + }) + return 0, nil, nil + + case linux.FIONBIO: + var set int32 + if _, err := t.CopyIn(args[2].Pointer(), &set); err != nil { + return 0, nil, err + } + flags := file.StatusFlags() + if set != 0 { + flags |= linux.O_NONBLOCK + } else { + flags &^= linux.O_NONBLOCK + } + return 0, nil, file.SetStatusFlags(t, t.Credentials(), flags) + + case linux.FIOASYNC: + var set int32 + if _, err := t.CopyIn(args[2].Pointer(), &set); err != nil { + return 0, nil, err + } + flags := file.StatusFlags() + if set != 0 { + flags |= linux.O_ASYNC + } else { + flags &^= linux.O_ASYNC + } + file.SetStatusFlags(t, t.Credentials(), flags) + return 0, nil, nil + + case linux.FIOGETOWN, linux.SIOCGPGRP: + var who int32 + owner, hasOwner := getAsyncOwner(t, file) + if hasOwner { + if owner.Type == linux.F_OWNER_PGRP { + who = -owner.PID + } else { + who = owner.PID + } + } + _, err := t.CopyOut(args[2].Pointer(), &who) + return 0, nil, err + + case linux.FIOSETOWN, linux.SIOCSPGRP: + var who int32 + if _, err := t.CopyIn(args[2].Pointer(), &who); err != nil { + return 0, nil, err + } + ownerType := int32(linux.F_OWNER_PID) + if who < 0 { + // Check for overflow before flipping the sign. + if who-1 > who { + return 0, nil, syserror.EINVAL + } + ownerType = linux.F_OWNER_PGRP + who = -who + } + return 0, nil, setAsyncOwner(t, file, ownerType, who) + } + + ret, err := file.Ioctl(t, t.MemoryManager(), args) + return ret, nil, err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/lock.go b/pkg/sentry/syscalls/linux/vfs2/lock.go new file mode 100644 index 000000000..b910b5a74 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/lock.go @@ -0,0 +1,64 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fs/lock" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Flock implements linux syscall flock(2). +func Flock(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + operation := args[1].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + // flock(2): EBADF fd is not an open file descriptor. + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + nonblocking := operation&linux.LOCK_NB != 0 + operation &^= linux.LOCK_NB + + var blocker lock.Blocker + if !nonblocking { + blocker = t + } + + switch operation { + case linux.LOCK_EX: + if err := file.LockBSD(t, lock.WriteLock, blocker); err != nil { + return 0, nil, err + } + case linux.LOCK_SH: + if err := file.LockBSD(t, lock.ReadLock, blocker); err != nil { + return 0, nil, err + } + case linux.LOCK_UN: + if err := file.UnlockBSD(t); err != nil { + return 0, nil, err + } + default: + // flock(2): EINVAL operation is invalid. + return 0, nil, syserror.EINVAL + } + + return 0, nil, nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/memfd.go b/pkg/sentry/syscalls/linux/vfs2/memfd.go new file mode 100644 index 000000000..c4c0f9e0a --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/memfd.go @@ -0,0 +1,64 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +const ( + memfdPrefix = "memfd:" + memfdMaxNameLen = linux.NAME_MAX - len(memfdPrefix) + memfdAllFlags = uint32(linux.MFD_CLOEXEC | linux.MFD_ALLOW_SEALING) +) + +// MemfdCreate implements the linux syscall memfd_create(2). +func MemfdCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + flags := args[1].Uint() + + if flags&^memfdAllFlags != 0 { + // Unknown bits in flags. + return 0, nil, syserror.EINVAL + } + + allowSeals := flags&linux.MFD_ALLOW_SEALING != 0 + cloExec := flags&linux.MFD_CLOEXEC != 0 + + name, err := t.CopyInString(addr, memfdMaxNameLen) + if err != nil { + return 0, nil, err + } + + shmMount := t.Kernel().ShmMount() + file, err := tmpfs.NewMemfd(t, t.Credentials(), shmMount, allowSeals, memfdPrefix+name) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + + fd, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{ + CloseOnExec: cloExec, + }) + if err != nil { + return 0, nil, err + } + + return uintptr(fd), nil, nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/mmap.go b/pkg/sentry/syscalls/linux/vfs2/mmap.go new file mode 100644 index 000000000..dc05c2994 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/mmap.go @@ -0,0 +1,92 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/memmap" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Mmap implements Linux syscall mmap(2). +func Mmap(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + prot := args[2].Int() + flags := args[3].Int() + fd := args[4].Int() + fixed := flags&linux.MAP_FIXED != 0 + private := flags&linux.MAP_PRIVATE != 0 + shared := flags&linux.MAP_SHARED != 0 + anon := flags&linux.MAP_ANONYMOUS != 0 + map32bit := flags&linux.MAP_32BIT != 0 + + // Require exactly one of MAP_PRIVATE and MAP_SHARED. + if private == shared { + return 0, nil, syserror.EINVAL + } + + opts := memmap.MMapOpts{ + Length: args[1].Uint64(), + Offset: args[5].Uint64(), + Addr: args[0].Pointer(), + Fixed: fixed, + Unmap: fixed, + Map32Bit: map32bit, + Private: private, + Perms: usermem.AccessType{ + Read: linux.PROT_READ&prot != 0, + Write: linux.PROT_WRITE&prot != 0, + Execute: linux.PROT_EXEC&prot != 0, + }, + MaxPerms: usermem.AnyAccess, + GrowsDown: linux.MAP_GROWSDOWN&flags != 0, + Precommit: linux.MAP_POPULATE&flags != 0, + } + if linux.MAP_LOCKED&flags != 0 { + opts.MLockMode = memmap.MLockEager + } + defer func() { + if opts.MappingIdentity != nil { + opts.MappingIdentity.DecRef(t) + } + }() + + if !anon { + // Convert the passed FD to a file reference. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // mmap unconditionally requires that the FD is readable. + if !file.IsReadable() { + return 0, nil, syserror.EACCES + } + // MAP_SHARED requires that the FD be writable for PROT_WRITE. + if shared && !file.IsWritable() { + opts.MaxPerms.Write = false + } + + if err := file.ConfigureMMap(t, &opts); err != nil { + return 0, nil, err + } + } + + rv, err := t.MemoryManager().MMap(t, opts) + return uintptr(rv), nil, err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/mount.go b/pkg/sentry/syscalls/linux/vfs2/mount.go new file mode 100644 index 000000000..4bd5c7ca2 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/mount.go @@ -0,0 +1,150 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Mount implements Linux syscall mount(2). +func Mount(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + sourceAddr := args[0].Pointer() + targetAddr := args[1].Pointer() + typeAddr := args[2].Pointer() + flags := args[3].Uint64() + dataAddr := args[4].Pointer() + + // For null-terminated strings related to mount(2), Linux copies in at most + // a page worth of data. See fs/namespace.c:copy_mount_string(). + fsType, err := t.CopyInString(typeAddr, usermem.PageSize) + if err != nil { + return 0, nil, err + } + source, err := t.CopyInString(sourceAddr, usermem.PageSize) + if err != nil { + return 0, nil, err + } + + targetPath, err := copyInPath(t, targetAddr) + if err != nil { + return 0, nil, err + } + + data := "" + if dataAddr != 0 { + // In Linux, a full page is always copied in regardless of null + // character placement, and the address is passed to each file system. + // Most file systems always treat this data as a string, though, and so + // do all of the ones we implement. + data, err = t.CopyInString(dataAddr, usermem.PageSize) + if err != nil { + return 0, nil, err + } + } + + // Ignore magic value that was required before Linux 2.4. + if flags&linux.MS_MGC_MSK == linux.MS_MGC_VAL { + flags = flags &^ linux.MS_MGC_MSK + } + + // Must have CAP_SYS_ADMIN in the current mount namespace's associated user + // namespace. + creds := t.Credentials() + if !creds.HasCapabilityIn(linux.CAP_SYS_ADMIN, t.MountNamespaceVFS2().Owner) { + return 0, nil, syserror.EPERM + } + + const unsupportedOps = linux.MS_REMOUNT | linux.MS_BIND | + linux.MS_SHARED | linux.MS_PRIVATE | linux.MS_SLAVE | + linux.MS_UNBINDABLE | linux.MS_MOVE + + // Silently allow MS_NOSUID, since we don't implement set-id bits + // anyway. + const unsupportedFlags = linux.MS_NODIRATIME | linux.MS_STRICTATIME + + // Linux just allows passing any flags to mount(2) - it won't fail when + // unknown or unsupported flags are passed. Since we don't implement + // everything, we fail explicitly on flags that are unimplemented. + if flags&(unsupportedOps|unsupportedFlags) != 0 { + return 0, nil, syserror.EINVAL + } + + var opts vfs.MountOptions + if flags&linux.MS_NOATIME == linux.MS_NOATIME { + opts.Flags.NoATime = true + } + if flags&linux.MS_NOEXEC == linux.MS_NOEXEC { + opts.Flags.NoExec = true + } + if flags&linux.MS_NODEV == linux.MS_NODEV { + opts.Flags.NoDev = true + } + if flags&linux.MS_NOSUID == linux.MS_NOSUID { + opts.Flags.NoSUID = true + } + if flags&linux.MS_RDONLY == linux.MS_RDONLY { + opts.ReadOnly = true + } + opts.GetFilesystemOptions.Data = data + + target, err := getTaskPathOperation(t, linux.AT_FDCWD, targetPath, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer target.Release(t) + + return 0, nil, t.Kernel().VFS().MountAt(t, creds, source, &target.pop, fsType, &opts) +} + +// Umount2 implements Linux syscall umount2(2). +func Umount2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + flags := args[1].Int() + + // Must have CAP_SYS_ADMIN in the mount namespace's associated user + // namespace. + // + // Currently, this is always the init task's user namespace. + creds := t.Credentials() + if !creds.HasCapabilityIn(linux.CAP_SYS_ADMIN, t.MountNamespaceVFS2().Owner) { + return 0, nil, syserror.EPERM + } + + const unsupported = linux.MNT_FORCE | linux.MNT_EXPIRE + if flags&unsupported != 0 { + return 0, nil, syserror.EINVAL + } + + path, err := copyInPath(t, addr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, nofollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + opts := vfs.UmountOptions{ + Flags: uint32(flags), + } + + return 0, nil, t.Kernel().VFS().UmountAt(t, creds, &tpop.pop, &opts) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/path.go b/pkg/sentry/syscalls/linux/vfs2/path.go new file mode 100644 index 000000000..90a511d9a --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/path.go @@ -0,0 +1,94 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +func copyInPath(t *kernel.Task, addr usermem.Addr) (fspath.Path, error) { + pathname, err := t.CopyInString(addr, linux.PATH_MAX) + if err != nil { + return fspath.Path{}, err + } + return fspath.Parse(pathname), nil +} + +type taskPathOperation struct { + pop vfs.PathOperation + haveStartRef bool +} + +func getTaskPathOperation(t *kernel.Task, dirfd int32, path fspath.Path, shouldAllowEmptyPath shouldAllowEmptyPath, shouldFollowFinalSymlink shouldFollowFinalSymlink) (taskPathOperation, error) { + root := t.FSContext().RootDirectoryVFS2() + start := root + haveStartRef := false + if !path.Absolute { + if !path.HasComponents() && !bool(shouldAllowEmptyPath) { + root.DecRef(t) + return taskPathOperation{}, syserror.ENOENT + } + if dirfd == linux.AT_FDCWD { + start = t.FSContext().WorkingDirectoryVFS2() + haveStartRef = true + } else { + dirfile := t.GetFileVFS2(dirfd) + if dirfile == nil { + root.DecRef(t) + return taskPathOperation{}, syserror.EBADF + } + start = dirfile.VirtualDentry() + start.IncRef() + haveStartRef = true + dirfile.DecRef(t) + } + } + return taskPathOperation{ + pop: vfs.PathOperation{ + Root: root, + Start: start, + Path: path, + FollowFinalSymlink: bool(shouldFollowFinalSymlink), + }, + haveStartRef: haveStartRef, + }, nil +} + +func (tpop *taskPathOperation) Release(t *kernel.Task) { + tpop.pop.Root.DecRef(t) + if tpop.haveStartRef { + tpop.pop.Start.DecRef(t) + tpop.haveStartRef = false + } +} + +type shouldAllowEmptyPath bool + +const ( + disallowEmptyPath shouldAllowEmptyPath = false + allowEmptyPath shouldAllowEmptyPath = true +) + +type shouldFollowFinalSymlink bool + +const ( + nofollowFinalSymlink shouldFollowFinalSymlink = false + followFinalSymlink shouldFollowFinalSymlink = true +) diff --git a/pkg/sentry/syscalls/linux/vfs2/pipe.go b/pkg/sentry/syscalls/linux/vfs2/pipe.go new file mode 100644 index 000000000..9b4848d9e --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/pipe.go @@ -0,0 +1,63 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/pipefs" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Pipe implements Linux syscall pipe(2). +func Pipe(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + return 0, nil, pipe2(t, addr, 0) +} + +// Pipe2 implements Linux syscall pipe2(2). +func Pipe2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + flags := args[1].Int() + return 0, nil, pipe2(t, addr, flags) +} + +func pipe2(t *kernel.Task, addr usermem.Addr, flags int32) error { + if flags&^(linux.O_NONBLOCK|linux.O_CLOEXEC) != 0 { + return syserror.EINVAL + } + r, w := pipefs.NewConnectedPipeFDs(t, t.Kernel().PipeMount(), uint32(flags&linux.O_NONBLOCK)) + defer r.DecRef(t) + defer w.DecRef(t) + + fds, err := t.NewFDsVFS2(0, []*vfs.FileDescription{r, w}, kernel.FDFlags{ + CloseOnExec: flags&linux.O_CLOEXEC != 0, + }) + if err != nil { + return err + } + if _, err := t.CopyOut(addr, fds); err != nil { + for _, fd := range fds { + if _, file := t.FDTable().Remove(fd); file != nil { + file.DecRef(t) + } + } + return err + } + return nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/poll.go b/pkg/sentry/syscalls/linux/vfs2/poll.go new file mode 100644 index 000000000..7b9d5e18a --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/poll.go @@ -0,0 +1,586 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "fmt" + "time" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/limits" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/pkg/waiter" +) + +// fileCap is the maximum allowable files for poll & select. This has no +// equivalent in Linux; it exists in gVisor since allocation failure in Go is +// unrecoverable. +const fileCap = 1024 * 1024 + +// Masks for "readable", "writable", and "exceptional" events as defined by +// select(2). +const ( + // selectReadEvents is analogous to the Linux kernel's + // fs/select.c:POLLIN_SET. + selectReadEvents = linux.POLLIN | linux.POLLHUP | linux.POLLERR + + // selectWriteEvents is analogous to the Linux kernel's + // fs/select.c:POLLOUT_SET. + selectWriteEvents = linux.POLLOUT | linux.POLLERR + + // selectExceptEvents is analogous to the Linux kernel's + // fs/select.c:POLLEX_SET. + selectExceptEvents = linux.POLLPRI +) + +// pollState tracks the associated file description and waiter of a PollFD. +type pollState struct { + file *vfs.FileDescription + waiter waiter.Entry +} + +// initReadiness gets the current ready mask for the file represented by the FD +// stored in pfd.FD. If a channel is passed in, the waiter entry in "state" is +// used to register with the file for event notifications, and a reference to +// the file is stored in "state". +func initReadiness(t *kernel.Task, pfd *linux.PollFD, state *pollState, ch chan struct{}) { + if pfd.FD < 0 { + pfd.REvents = 0 + return + } + + file := t.GetFileVFS2(pfd.FD) + if file == nil { + pfd.REvents = linux.POLLNVAL + return + } + + if ch == nil { + defer file.DecRef(t) + } else { + state.file = file + state.waiter, _ = waiter.NewChannelEntry(ch) + file.EventRegister(&state.waiter, waiter.EventMaskFromLinux(uint32(pfd.Events))) + } + + r := file.Readiness(waiter.EventMaskFromLinux(uint32(pfd.Events))) + pfd.REvents = int16(r.ToLinux()) & pfd.Events +} + +// releaseState releases all the pollState in "state". +func releaseState(t *kernel.Task, state []pollState) { + for i := range state { + if state[i].file != nil { + state[i].file.EventUnregister(&state[i].waiter) + state[i].file.DecRef(t) + } + } +} + +// pollBlock polls the PollFDs in "pfd" with a bounded time specified in "timeout" +// when "timeout" is greater than zero. +// +// pollBlock returns the remaining timeout, which is always 0 on a timeout; and 0 or +// positive if interrupted by a signal. +func pollBlock(t *kernel.Task, pfd []linux.PollFD, timeout time.Duration) (time.Duration, uintptr, error) { + var ch chan struct{} + if timeout != 0 { + ch = make(chan struct{}, 1) + } + + // Register for event notification in the files involved if we may + // block (timeout not zero). Once we find a file that has a non-zero + // result, we stop registering for events but still go through all files + // to get their ready masks. + state := make([]pollState, len(pfd)) + defer releaseState(t, state) + n := uintptr(0) + for i := range pfd { + initReadiness(t, &pfd[i], &state[i], ch) + if pfd[i].REvents != 0 { + n++ + ch = nil + } + } + + if timeout == 0 { + return timeout, n, nil + } + + haveTimeout := timeout >= 0 + + for n == 0 { + var err error + // Wait for a notification. + timeout, err = t.BlockWithTimeout(ch, haveTimeout, timeout) + if err != nil { + if err == syserror.ETIMEDOUT { + err = nil + } + return timeout, 0, err + } + + // We got notified, count how many files are ready. If none, + // then this was a spurious notification, and we just go back + // to sleep with the remaining timeout. + for i := range state { + if state[i].file == nil { + continue + } + + r := state[i].file.Readiness(waiter.EventMaskFromLinux(uint32(pfd[i].Events))) + rl := int16(r.ToLinux()) & pfd[i].Events + if rl != 0 { + pfd[i].REvents = rl + n++ + } + } + } + + return timeout, n, nil +} + +// copyInPollFDs copies an array of struct pollfd unless nfds exceeds the max. +func copyInPollFDs(t *kernel.Task, addr usermem.Addr, nfds uint) ([]linux.PollFD, error) { + if uint64(nfds) > t.ThreadGroup().Limits().GetCapped(limits.NumberOfFiles, fileCap) { + return nil, syserror.EINVAL + } + + pfd := make([]linux.PollFD, nfds) + if nfds > 0 { + if _, err := t.CopyIn(addr, &pfd); err != nil { + return nil, err + } + } + + return pfd, nil +} + +func doPoll(t *kernel.Task, addr usermem.Addr, nfds uint, timeout time.Duration) (time.Duration, uintptr, error) { + pfd, err := copyInPollFDs(t, addr, nfds) + if err != nil { + return timeout, 0, err + } + + // Compatibility warning: Linux adds POLLHUP and POLLERR just before + // polling, in fs/select.c:do_pollfd(). Since pfd is copied out after + // polling, changing event masks here is an application-visible difference. + // (Linux also doesn't copy out event masks at all, only revents.) + for i := range pfd { + pfd[i].Events |= linux.POLLHUP | linux.POLLERR + } + remainingTimeout, n, err := pollBlock(t, pfd, timeout) + err = syserror.ConvertIntr(err, syserror.EINTR) + + // The poll entries are copied out regardless of whether + // any are set or not. This aligns with the Linux behavior. + if nfds > 0 && err == nil { + if _, err := t.CopyOut(addr, pfd); err != nil { + return remainingTimeout, 0, err + } + } + + return remainingTimeout, n, err +} + +// CopyInFDSet copies an fd set from select(2)/pselect(2). +func CopyInFDSet(t *kernel.Task, addr usermem.Addr, nBytes, nBitsInLastPartialByte int) ([]byte, error) { + set := make([]byte, nBytes) + + if addr != 0 { + if _, err := t.CopyIn(addr, &set); err != nil { + return nil, err + } + // If we only use part of the last byte, mask out the extraneous bits. + // + // N.B. This only works on little-endian architectures. + if nBitsInLastPartialByte != 0 { + set[nBytes-1] &^= byte(0xff) << nBitsInLastPartialByte + } + } + return set, nil +} + +func doSelect(t *kernel.Task, nfds int, readFDs, writeFDs, exceptFDs usermem.Addr, timeout time.Duration) (uintptr, error) { + if nfds < 0 || nfds > fileCap { + return 0, syserror.EINVAL + } + + // Calculate the size of the fd sets (one bit per fd). + nBytes := (nfds + 7) / 8 + nBitsInLastPartialByte := nfds % 8 + + // Capture all the provided input vectors. + r, err := CopyInFDSet(t, readFDs, nBytes, nBitsInLastPartialByte) + if err != nil { + return 0, err + } + w, err := CopyInFDSet(t, writeFDs, nBytes, nBitsInLastPartialByte) + if err != nil { + return 0, err + } + e, err := CopyInFDSet(t, exceptFDs, nBytes, nBitsInLastPartialByte) + if err != nil { + return 0, err + } + + // Count how many FDs are actually being requested so that we can build + // a PollFD array. + fdCount := 0 + for i := 0; i < nBytes; i++ { + v := r[i] | w[i] | e[i] + for v != 0 { + v &= (v - 1) + fdCount++ + } + } + + // Build the PollFD array. + pfd := make([]linux.PollFD, 0, fdCount) + var fd int32 + for i := 0; i < nBytes; i++ { + rV, wV, eV := r[i], w[i], e[i] + v := rV | wV | eV + m := byte(1) + for j := 0; j < 8; j++ { + if (v & m) != 0 { + // Make sure the fd is valid and decrement the reference + // immediately to ensure we don't leak. Note, another thread + // might be about to close fd. This is racy, but that's + // OK. Linux is racy in the same way. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, syserror.EBADF + } + file.DecRef(t) + + var mask int16 + if (rV & m) != 0 { + mask |= selectReadEvents + } + + if (wV & m) != 0 { + mask |= selectWriteEvents + } + + if (eV & m) != 0 { + mask |= selectExceptEvents + } + + pfd = append(pfd, linux.PollFD{ + FD: fd, + Events: mask, + }) + } + + fd++ + m <<= 1 + } + } + + // Do the syscall, then count the number of bits set. + if _, _, err = pollBlock(t, pfd, timeout); err != nil { + return 0, syserror.ConvertIntr(err, syserror.EINTR) + } + + // r, w, and e are currently event mask bitsets; unset bits corresponding + // to events that *didn't* occur. + bitSetCount := uintptr(0) + for idx := range pfd { + events := pfd[idx].REvents + i, j := pfd[idx].FD/8, uint(pfd[idx].FD%8) + m := byte(1) << j + if r[i]&m != 0 { + if (events & selectReadEvents) != 0 { + bitSetCount++ + } else { + r[i] &^= m + } + } + if w[i]&m != 0 { + if (events & selectWriteEvents) != 0 { + bitSetCount++ + } else { + w[i] &^= m + } + } + if e[i]&m != 0 { + if (events & selectExceptEvents) != 0 { + bitSetCount++ + } else { + e[i] &^= m + } + } + } + + // Copy updated vectors back. + if readFDs != 0 { + if _, err := t.CopyOut(readFDs, r); err != nil { + return 0, err + } + } + + if writeFDs != 0 { + if _, err := t.CopyOut(writeFDs, w); err != nil { + return 0, err + } + } + + if exceptFDs != 0 { + if _, err := t.CopyOut(exceptFDs, e); err != nil { + return 0, err + } + } + + return bitSetCount, nil +} + +// timeoutRemaining returns the amount of time remaining for the specified +// timeout or 0 if it has elapsed. +// +// startNs must be from CLOCK_MONOTONIC. +func timeoutRemaining(t *kernel.Task, startNs ktime.Time, timeout time.Duration) time.Duration { + now := t.Kernel().MonotonicClock().Now() + remaining := timeout - now.Sub(startNs) + if remaining < 0 { + remaining = 0 + } + return remaining +} + +// copyOutTimespecRemaining copies the time remaining in timeout to timespecAddr. +// +// startNs must be from CLOCK_MONOTONIC. +func copyOutTimespecRemaining(t *kernel.Task, startNs ktime.Time, timeout time.Duration, timespecAddr usermem.Addr) error { + if timeout <= 0 { + return nil + } + remaining := timeoutRemaining(t, startNs, timeout) + tsRemaining := linux.NsecToTimespec(remaining.Nanoseconds()) + _, err := tsRemaining.CopyOut(t, timespecAddr) + return err +} + +// copyOutTimevalRemaining copies the time remaining in timeout to timevalAddr. +// +// startNs must be from CLOCK_MONOTONIC. +func copyOutTimevalRemaining(t *kernel.Task, startNs ktime.Time, timeout time.Duration, timevalAddr usermem.Addr) error { + if timeout <= 0 { + return nil + } + remaining := timeoutRemaining(t, startNs, timeout) + tvRemaining := linux.NsecToTimeval(remaining.Nanoseconds()) + _, err := tvRemaining.CopyOut(t, timevalAddr) + return err +} + +// pollRestartBlock encapsulates the state required to restart poll(2) via +// restart_syscall(2). +// +// +stateify savable +type pollRestartBlock struct { + pfdAddr usermem.Addr + nfds uint + timeout time.Duration +} + +// Restart implements kernel.SyscallRestartBlock.Restart. +func (p *pollRestartBlock) Restart(t *kernel.Task) (uintptr, error) { + return poll(t, p.pfdAddr, p.nfds, p.timeout) +} + +func poll(t *kernel.Task, pfdAddr usermem.Addr, nfds uint, timeout time.Duration) (uintptr, error) { + remainingTimeout, n, err := doPoll(t, pfdAddr, nfds, timeout) + // On an interrupt poll(2) is restarted with the remaining timeout. + if err == syserror.EINTR { + t.SetSyscallRestartBlock(&pollRestartBlock{ + pfdAddr: pfdAddr, + nfds: nfds, + timeout: remainingTimeout, + }) + return 0, kernel.ERESTART_RESTARTBLOCK + } + return n, err +} + +// Poll implements linux syscall poll(2). +func Poll(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pfdAddr := args[0].Pointer() + nfds := uint(args[1].Uint()) // poll(2) uses unsigned long. + timeout := time.Duration(args[2].Int()) * time.Millisecond + n, err := poll(t, pfdAddr, nfds, timeout) + return n, nil, err +} + +// Ppoll implements linux syscall ppoll(2). +func Ppoll(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pfdAddr := args[0].Pointer() + nfds := uint(args[1].Uint()) // poll(2) uses unsigned long. + timespecAddr := args[2].Pointer() + maskAddr := args[3].Pointer() + maskSize := uint(args[4].Uint()) + + timeout, err := copyTimespecInToDuration(t, timespecAddr) + if err != nil { + return 0, nil, err + } + + var startNs ktime.Time + if timeout > 0 { + startNs = t.Kernel().MonotonicClock().Now() + } + + if err := setTempSignalSet(t, maskAddr, maskSize); err != nil { + return 0, nil, err + } + + _, n, err := doPoll(t, pfdAddr, nfds, timeout) + copyErr := copyOutTimespecRemaining(t, startNs, timeout, timespecAddr) + // doPoll returns EINTR if interrupted, but ppoll is normally restartable + // if interrupted by something other than a signal handled by the + // application (i.e. returns ERESTARTNOHAND). However, if + // copyOutTimespecRemaining failed, then the restarted ppoll would use the + // wrong timeout, so the error should be left as EINTR. + // + // Note that this means that if err is nil but copyErr is not, copyErr is + // ignored. This is consistent with Linux. + if err == syserror.EINTR && copyErr == nil { + err = kernel.ERESTARTNOHAND + } + return n, nil, err +} + +// Select implements linux syscall select(2). +func Select(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + nfds := int(args[0].Int()) // select(2) uses an int. + readFDs := args[1].Pointer() + writeFDs := args[2].Pointer() + exceptFDs := args[3].Pointer() + timevalAddr := args[4].Pointer() + + // Use a negative Duration to indicate "no timeout". + timeout := time.Duration(-1) + if timevalAddr != 0 { + var timeval linux.Timeval + if _, err := timeval.CopyIn(t, timevalAddr); err != nil { + return 0, nil, err + } + if timeval.Sec < 0 || timeval.Usec < 0 { + return 0, nil, syserror.EINVAL + } + timeout = time.Duration(timeval.ToNsecCapped()) + } + startNs := t.Kernel().MonotonicClock().Now() + n, err := doSelect(t, nfds, readFDs, writeFDs, exceptFDs, timeout) + copyErr := copyOutTimevalRemaining(t, startNs, timeout, timevalAddr) + // See comment in Ppoll. + if err == syserror.EINTR && copyErr == nil { + err = kernel.ERESTARTNOHAND + } + return n, nil, err +} + +// Pselect implements linux syscall pselect(2). +func Pselect(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + nfds := int(args[0].Int()) // select(2) uses an int. + readFDs := args[1].Pointer() + writeFDs := args[2].Pointer() + exceptFDs := args[3].Pointer() + timespecAddr := args[4].Pointer() + maskWithSizeAddr := args[5].Pointer() + + timeout, err := copyTimespecInToDuration(t, timespecAddr) + if err != nil { + return 0, nil, err + } + + var startNs ktime.Time + if timeout > 0 { + startNs = t.Kernel().MonotonicClock().Now() + } + + if maskWithSizeAddr != 0 { + if t.Arch().Width() != 8 { + panic(fmt.Sprintf("unsupported sizeof(void*): %d", t.Arch().Width())) + } + var maskStruct sigSetWithSize + if _, err := maskStruct.CopyIn(t, maskWithSizeAddr); err != nil { + return 0, nil, err + } + if err := setTempSignalSet(t, usermem.Addr(maskStruct.sigsetAddr), uint(maskStruct.sizeofSigset)); err != nil { + return 0, nil, err + } + } + + n, err := doSelect(t, nfds, readFDs, writeFDs, exceptFDs, timeout) + copyErr := copyOutTimespecRemaining(t, startNs, timeout, timespecAddr) + // See comment in Ppoll. + if err == syserror.EINTR && copyErr == nil { + err = kernel.ERESTARTNOHAND + } + return n, nil, err +} + +// +marshal +type sigSetWithSize struct { + sigsetAddr uint64 + sizeofSigset uint64 +} + +// copyTimespecInToDuration copies a Timespec from the untrusted app range, +// validates it and converts it to a Duration. +// +// If the Timespec is larger than what can be represented in a Duration, the +// returned value is the maximum that Duration will allow. +// +// If timespecAddr is NULL, the returned value is negative. +func copyTimespecInToDuration(t *kernel.Task, timespecAddr usermem.Addr) (time.Duration, error) { + // Use a negative Duration to indicate "no timeout". + timeout := time.Duration(-1) + if timespecAddr != 0 { + var timespec linux.Timespec + if _, err := timespec.CopyIn(t, timespecAddr); err != nil { + return 0, err + } + if !timespec.Valid() { + return 0, syserror.EINVAL + } + timeout = time.Duration(timespec.ToNsecCapped()) + } + return timeout, nil +} + +func setTempSignalSet(t *kernel.Task, maskAddr usermem.Addr, maskSize uint) error { + if maskAddr == 0 { + return nil + } + if maskSize != linux.SignalSetSize { + return syserror.EINVAL + } + var mask linux.SignalSet + if _, err := mask.CopyIn(t, maskAddr); err != nil { + return err + } + mask &^= kernel.UnblockableSignals + oldmask := t.SignalMask() + t.SetSignalMask(mask) + t.SetSavedSignalMask(oldmask) + return nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/read_write.go b/pkg/sentry/syscalls/linux/vfs2/read_write.go new file mode 100644 index 000000000..a905dae0a --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/read_write.go @@ -0,0 +1,641 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "time" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/socket" + slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/pkg/waiter" +) + +const ( + eventMaskRead = waiter.EventIn | waiter.EventHUp | waiter.EventErr + eventMaskWrite = waiter.EventOut | waiter.EventHUp | waiter.EventErr +) + +// Read implements Linux syscall read(2). +func Read(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + size := args[2].SizeT() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the size is legitimate. + si := int(size) + if si < 0 { + return 0, nil, syserror.EINVAL + } + + // Get the destination of the read. + dst, err := t.SingleIOSequence(addr, si, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := read(t, file, dst, vfs.ReadOptions{}) + t.IOUsage().AccountReadSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "read", file) +} + +// Readv implements Linux syscall readv(2). +func Readv(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + iovcnt := int(args[2].Int()) + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Get the destination of the read. + dst, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := read(t, file, dst, vfs.ReadOptions{}) + t.IOUsage().AccountReadSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "readv", file) +} + +func read(t *kernel.Task, file *vfs.FileDescription, dst usermem.IOSequence, opts vfs.ReadOptions) (int64, error) { + n, err := file.Read(t, dst, opts) + if err != syserror.ErrWouldBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return n, err + } + + allowBlock, deadline, hasDeadline := blockPolicy(t, file) + if !allowBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return n, err + } + + // Register for notifications. + w, ch := waiter.NewChannelEntry(nil) + file.EventRegister(&w, eventMaskRead) + + total := n + for { + // Shorten dst to reflect bytes previously read. + dst = dst.DropFirst(int(n)) + + // Issue the request and break out if it completes with anything other than + // "would block". + n, err = file.Read(t, dst, opts) + total += n + if err != syserror.ErrWouldBlock { + break + } + + // Wait for a notification that we should retry. + if err = t.BlockWithDeadline(ch, hasDeadline, deadline); err != nil { + if err == syserror.ETIMEDOUT { + err = syserror.ErrWouldBlock + } + break + } + } + file.EventUnregister(&w) + + if total > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return total, err +} + +// Pread64 implements Linux syscall pread64(2). +func Pread64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + size := args[2].SizeT() + offset := args[3].Int64() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the offset is legitimate and does not overflow. + if offset < 0 || offset+int64(size) < 0 { + return 0, nil, syserror.EINVAL + } + + // Check that the size is legitimate. + si := int(size) + if si < 0 { + return 0, nil, syserror.EINVAL + } + + // Get the destination of the read. + dst, err := t.SingleIOSequence(addr, si, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := pread(t, file, dst, offset, vfs.ReadOptions{}) + t.IOUsage().AccountReadSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "pread64", file) +} + +// Preadv implements Linux syscall preadv(2). +func Preadv(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + iovcnt := int(args[2].Int()) + offset := args[3].Int64() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the offset is legitimate. + if offset < 0 { + return 0, nil, syserror.EINVAL + } + + // Get the destination of the read. + dst, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := pread(t, file, dst, offset, vfs.ReadOptions{}) + t.IOUsage().AccountReadSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "preadv", file) +} + +// Preadv2 implements Linux syscall preadv2(2). +func Preadv2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + // While the glibc signature is + // preadv2(int fd, struct iovec* iov, int iov_cnt, off_t offset, int flags) + // the actual syscall + // (https://elixir.bootlin.com/linux/v5.5/source/fs/read_write.c#L1142) + // splits the offset argument into a high/low value for compatibility with + // 32-bit architectures. The flags argument is the 6th argument (index 5). + fd := args[0].Int() + addr := args[1].Pointer() + iovcnt := int(args[2].Int()) + offset := args[3].Int64() + flags := args[5].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the offset is legitimate. + if offset < -1 { + return 0, nil, syserror.EINVAL + } + + // Get the destination of the read. + dst, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + opts := vfs.ReadOptions{ + Flags: uint32(flags), + } + var n int64 + if offset == -1 { + n, err = read(t, file, dst, opts) + } else { + n, err = pread(t, file, dst, offset, opts) + } + t.IOUsage().AccountReadSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "preadv2", file) +} + +func pread(t *kernel.Task, file *vfs.FileDescription, dst usermem.IOSequence, offset int64, opts vfs.ReadOptions) (int64, error) { + n, err := file.PRead(t, dst, offset, opts) + if err != syserror.ErrWouldBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return n, err + } + + allowBlock, deadline, hasDeadline := blockPolicy(t, file) + if !allowBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return n, err + } + + // Register for notifications. + w, ch := waiter.NewChannelEntry(nil) + file.EventRegister(&w, eventMaskRead) + + total := n + for { + // Shorten dst to reflect bytes previously read. + dst = dst.DropFirst(int(n)) + + // Issue the request and break out if it completes with anything other than + // "would block". + n, err = file.PRead(t, dst, offset+total, opts) + total += n + if err != syserror.ErrWouldBlock { + break + } + + // Wait for a notification that we should retry. + if err = t.BlockWithDeadline(ch, hasDeadline, deadline); err != nil { + if err == syserror.ETIMEDOUT { + err = syserror.ErrWouldBlock + } + break + } + } + file.EventUnregister(&w) + + if total > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return total, err +} + +// Write implements Linux syscall write(2). +func Write(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + size := args[2].SizeT() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the size is legitimate. + si := int(size) + if si < 0 { + return 0, nil, syserror.EINVAL + } + + // Get the source of the write. + src, err := t.SingleIOSequence(addr, si, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := write(t, file, src, vfs.WriteOptions{}) + t.IOUsage().AccountWriteSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "write", file) +} + +// Writev implements Linux syscall writev(2). +func Writev(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + iovcnt := int(args[2].Int()) + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Get the source of the write. + src, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := write(t, file, src, vfs.WriteOptions{}) + t.IOUsage().AccountWriteSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "writev", file) +} + +func write(t *kernel.Task, file *vfs.FileDescription, src usermem.IOSequence, opts vfs.WriteOptions) (int64, error) { + n, err := file.Write(t, src, opts) + if err != syserror.ErrWouldBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + } + return n, err + } + + allowBlock, deadline, hasDeadline := blockPolicy(t, file) + if !allowBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + } + return n, err + } + + // Register for notifications. + w, ch := waiter.NewChannelEntry(nil) + file.EventRegister(&w, eventMaskWrite) + + total := n + for { + // Shorten src to reflect bytes previously written. + src = src.DropFirst(int(n)) + + // Issue the request and break out if it completes with anything other than + // "would block". + n, err = file.Write(t, src, opts) + total += n + if err != syserror.ErrWouldBlock { + break + } + + // Wait for a notification that we should retry. + if err = t.BlockWithDeadline(ch, hasDeadline, deadline); err != nil { + if err == syserror.ETIMEDOUT { + err = syserror.ErrWouldBlock + } + break + } + } + file.EventUnregister(&w) + + if total > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + } + return total, err +} + +// Pwrite64 implements Linux syscall pwrite64(2). +func Pwrite64(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + size := args[2].SizeT() + offset := args[3].Int64() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the offset is legitimate and does not overflow. + if offset < 0 || offset+int64(size) < 0 { + return 0, nil, syserror.EINVAL + } + + // Check that the size is legitimate. + si := int(size) + if si < 0 { + return 0, nil, syserror.EINVAL + } + + // Get the source of the write. + src, err := t.SingleIOSequence(addr, si, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := pwrite(t, file, src, offset, vfs.WriteOptions{}) + t.IOUsage().AccountWriteSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "pwrite64", file) +} + +// Pwritev implements Linux syscall pwritev(2). +func Pwritev(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + iovcnt := int(args[2].Int()) + offset := args[3].Int64() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the offset is legitimate. + if offset < 0 { + return 0, nil, syserror.EINVAL + } + + // Get the source of the write. + src, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + n, err := pwrite(t, file, src, offset, vfs.WriteOptions{}) + t.IOUsage().AccountReadSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "pwritev", file) +} + +// Pwritev2 implements Linux syscall pwritev2(2). +func Pwritev2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + // While the glibc signature is + // pwritev2(int fd, struct iovec* iov, int iov_cnt, off_t offset, int flags) + // the actual syscall + // (https://elixir.bootlin.com/linux/v5.5/source/fs/read_write.c#L1162) + // splits the offset argument into a high/low value for compatibility with + // 32-bit architectures. The flags argument is the 6th argument (index 5). + fd := args[0].Int() + addr := args[1].Pointer() + iovcnt := int(args[2].Int()) + offset := args[3].Int64() + flags := args[5].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the offset is legitimate. + if offset < -1 { + return 0, nil, syserror.EINVAL + } + + // Get the source of the write. + src, err := t.IovecsIOSequence(addr, iovcnt, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, nil, err + } + + opts := vfs.WriteOptions{ + Flags: uint32(flags), + } + var n int64 + if offset == -1 { + n, err = write(t, file, src, opts) + } else { + n, err = pwrite(t, file, src, offset, opts) + } + t.IOUsage().AccountWriteSyscall(n) + return uintptr(n), nil, slinux.HandleIOErrorVFS2(t, n != 0, err, kernel.ERESTARTSYS, "pwritev2", file) +} + +func pwrite(t *kernel.Task, file *vfs.FileDescription, src usermem.IOSequence, offset int64, opts vfs.WriteOptions) (int64, error) { + n, err := file.PWrite(t, src, offset, opts) + if err != syserror.ErrWouldBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + } + return n, err + } + + allowBlock, deadline, hasDeadline := blockPolicy(t, file) + if !allowBlock { + if n > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return n, err + } + + // Register for notifications. + w, ch := waiter.NewChannelEntry(nil) + file.EventRegister(&w, eventMaskWrite) + + total := n + for { + // Shorten src to reflect bytes previously written. + src = src.DropFirst(int(n)) + + // Issue the request and break out if it completes with anything other than + // "would block". + n, err = file.PWrite(t, src, offset+total, opts) + total += n + if err != syserror.ErrWouldBlock { + break + } + + // Wait for a notification that we should retry. + if err = t.BlockWithDeadline(ch, hasDeadline, deadline); err != nil { + if err == syserror.ETIMEDOUT { + err = syserror.ErrWouldBlock + } + break + } + } + file.EventUnregister(&w) + + if total > 0 { + file.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + } + return total, err +} + +func blockPolicy(t *kernel.Task, file *vfs.FileDescription) (allowBlock bool, deadline ktime.Time, hasDeadline bool) { + if file.StatusFlags()&linux.O_NONBLOCK != 0 { + return false, ktime.Time{}, false + } + // Sockets support read/write timeouts. + if s, ok := file.Impl().(socket.SocketVFS2); ok { + dl := s.RecvTimeout() + if dl < 0 { + return false, ktime.Time{}, false + } + if dl > 0 { + return true, t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond), true + } + } + return true, ktime.Time{}, false +} + +// Lseek implements Linux syscall lseek(2). +func Lseek(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + offset := args[1].Int64() + whence := args[2].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + newoff, err := file.Seek(t, offset, whence) + return uintptr(newoff), nil, err +} + +// Readahead implements readahead(2). +func Readahead(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + offset := args[1].Int64() + size := args[2].SizeT() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Check that the file is readable. + if !file.IsReadable() { + return 0, nil, syserror.EBADF + } + + // Check that the size is valid. + if int(size) < 0 { + return 0, nil, syserror.EINVAL + } + + // Check that the offset is legitimate and does not overflow. + if offset < 0 || offset+int64(size) < 0 { + return 0, nil, syserror.EINVAL + } + + // Return EINVAL; if the underlying file type does not support readahead, + // then Linux will return EINVAL to indicate as much. In the future, we + // may extend this function to actually support readahead hints. + return 0, nil, syserror.EINVAL +} diff --git a/pkg/sentry/syscalls/linux/vfs2/setstat.go b/pkg/sentry/syscalls/linux/vfs2/setstat.go new file mode 100644 index 000000000..5e6eb13ba --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/setstat.go @@ -0,0 +1,484 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/limits" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +const chmodMask = 0777 | linux.S_ISUID | linux.S_ISGID | linux.S_ISVTX + +// Chmod implements Linux syscall chmod(2). +func Chmod(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + mode := args[1].ModeT() + return 0, nil, fchmodat(t, linux.AT_FDCWD, pathAddr, mode) +} + +// Fchmodat implements Linux syscall fchmodat(2). +func Fchmodat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + mode := args[2].ModeT() + return 0, nil, fchmodat(t, dirfd, pathAddr, mode) +} + +func fchmodat(t *kernel.Task, dirfd int32, pathAddr usermem.Addr, mode uint) error { + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + + return setstatat(t, dirfd, path, disallowEmptyPath, followFinalSymlink, &vfs.SetStatOptions{ + Stat: linux.Statx{ + Mask: linux.STATX_MODE, + Mode: uint16(mode & chmodMask), + }, + }) +} + +// Fchmod implements Linux syscall fchmod(2). +func Fchmod(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + mode := args[1].ModeT() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + return 0, nil, file.SetStat(t, vfs.SetStatOptions{ + Stat: linux.Statx{ + Mask: linux.STATX_MODE, + Mode: uint16(mode & chmodMask), + }, + }) +} + +// Chown implements Linux syscall chown(2). +func Chown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + owner := args[1].Int() + group := args[2].Int() + return 0, nil, fchownat(t, linux.AT_FDCWD, pathAddr, owner, group, 0 /* flags */) +} + +// Lchown implements Linux syscall lchown(2). +func Lchown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + owner := args[1].Int() + group := args[2].Int() + return 0, nil, fchownat(t, linux.AT_FDCWD, pathAddr, owner, group, linux.AT_SYMLINK_NOFOLLOW) +} + +// Fchownat implements Linux syscall fchownat(2). +func Fchownat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + owner := args[2].Int() + group := args[3].Int() + flags := args[4].Int() + return 0, nil, fchownat(t, dirfd, pathAddr, owner, group, flags) +} + +func fchownat(t *kernel.Task, dirfd int32, pathAddr usermem.Addr, owner, group, flags int32) error { + if flags&^(linux.AT_EMPTY_PATH|linux.AT_SYMLINK_NOFOLLOW) != 0 { + return syserror.EINVAL + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + + var opts vfs.SetStatOptions + if err := populateSetStatOptionsForChown(t, owner, group, &opts); err != nil { + return err + } + + return setstatat(t, dirfd, path, shouldAllowEmptyPath(flags&linux.AT_EMPTY_PATH != 0), shouldFollowFinalSymlink(flags&linux.AT_SYMLINK_NOFOLLOW == 0), &opts) +} + +func populateSetStatOptionsForChown(t *kernel.Task, owner, group int32, opts *vfs.SetStatOptions) error { + userns := t.UserNamespace() + if owner != -1 { + kuid := userns.MapToKUID(auth.UID(owner)) + if !kuid.Ok() { + return syserror.EINVAL + } + opts.Stat.Mask |= linux.STATX_UID + opts.Stat.UID = uint32(kuid) + } + if group != -1 { + kgid := userns.MapToKGID(auth.GID(group)) + if !kgid.Ok() { + return syserror.EINVAL + } + opts.Stat.Mask |= linux.STATX_GID + opts.Stat.GID = uint32(kgid) + } + return nil +} + +// Fchown implements Linux syscall fchown(2). +func Fchown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + owner := args[1].Int() + group := args[2].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + var opts vfs.SetStatOptions + if err := populateSetStatOptionsForChown(t, owner, group, &opts); err != nil { + return 0, nil, err + } + return 0, nil, file.SetStat(t, opts) +} + +// Truncate implements Linux syscall truncate(2). +func Truncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + length := args[1].Int64() + + if length < 0 { + return 0, nil, syserror.EINVAL + } + + path, err := copyInPath(t, addr) + if err != nil { + return 0, nil, err + } + + err = setstatat(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink, &vfs.SetStatOptions{ + Stat: linux.Statx{ + Mask: linux.STATX_SIZE, + Size: uint64(length), + }, + NeedWritePerm: true, + }) + return 0, nil, handleSetSizeError(t, err) +} + +// Ftruncate implements Linux syscall ftruncate(2). +func Ftruncate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + length := args[1].Int64() + + if length < 0 { + return 0, nil, syserror.EINVAL + } + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + if !file.IsWritable() { + return 0, nil, syserror.EINVAL + } + + err := file.SetStat(t, vfs.SetStatOptions{ + Stat: linux.Statx{ + Mask: linux.STATX_SIZE, + Size: uint64(length), + }, + }) + return 0, nil, handleSetSizeError(t, err) +} + +// Fallocate implements linux system call fallocate(2). +func Fallocate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + mode := args[1].Uint64() + offset := args[2].Int64() + length := args[3].Int64() + + file := t.GetFileVFS2(fd) + + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + if !file.IsWritable() { + return 0, nil, syserror.EBADF + } + + if mode != 0 { + return 0, nil, syserror.ENOTSUP + } + + if offset < 0 || length <= 0 { + return 0, nil, syserror.EINVAL + } + + size := offset + length + + if size < 0 { + return 0, nil, syserror.EFBIG + } + + limit := limits.FromContext(t).Get(limits.FileSize).Cur + + if uint64(size) >= limit { + t.SendSignal(&arch.SignalInfo{ + Signo: int32(linux.SIGXFSZ), + Code: arch.SignalInfoUser, + }) + return 0, nil, syserror.EFBIG + } + + if err := file.Allocate(t, mode, uint64(offset), uint64(length)); err != nil { + return 0, nil, err + } + + file.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + return 0, nil, nil +} + +// Utime implements Linux syscall utime(2). +func Utime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + timesAddr := args[1].Pointer() + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + + opts := vfs.SetStatOptions{ + Stat: linux.Statx{ + Mask: linux.STATX_ATIME | linux.STATX_MTIME, + }, + } + if timesAddr == 0 { + opts.Stat.Atime.Nsec = linux.UTIME_NOW + opts.Stat.Mtime.Nsec = linux.UTIME_NOW + } else { + var times linux.Utime + if _, err := times.CopyIn(t, timesAddr); err != nil { + return 0, nil, err + } + opts.Stat.Atime.Sec = times.Actime + opts.Stat.Mtime.Sec = times.Modtime + } + + return 0, nil, setstatat(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink, &opts) +} + +// Utimes implements Linux syscall utimes(2). +func Utimes(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + timesAddr := args[1].Pointer() + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + + var opts vfs.SetStatOptions + if err := populateSetStatOptionsForUtimes(t, timesAddr, &opts); err != nil { + return 0, nil, err + } + + return 0, nil, setstatat(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink, &opts) +} + +// Futimesat implements Linux syscall futimesat(2). +func Futimesat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + timesAddr := args[2].Pointer() + + // "If filename is NULL and dfd refers to an open file, then operate on the + // file. Otherwise look up filename, possibly using dfd as a starting + // point." - fs/utimes.c + var path fspath.Path + shouldAllowEmptyPath := allowEmptyPath + if dirfd == linux.AT_FDCWD || pathAddr != 0 { + var err error + path, err = copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + shouldAllowEmptyPath = disallowEmptyPath + } + + var opts vfs.SetStatOptions + if err := populateSetStatOptionsForUtimes(t, timesAddr, &opts); err != nil { + return 0, nil, err + } + + return 0, nil, setstatat(t, dirfd, path, shouldAllowEmptyPath, followFinalSymlink, &opts) +} + +func populateSetStatOptionsForUtimes(t *kernel.Task, timesAddr usermem.Addr, opts *vfs.SetStatOptions) error { + if timesAddr == 0 { + opts.Stat.Mask = linux.STATX_ATIME | linux.STATX_MTIME + opts.Stat.Atime.Nsec = linux.UTIME_NOW + opts.Stat.Mtime.Nsec = linux.UTIME_NOW + return nil + } + var times [2]linux.Timeval + if _, err := t.CopyIn(timesAddr, ×); err != nil { + return err + } + if times[0].Usec < 0 || times[0].Usec > 999999 || times[1].Usec < 0 || times[1].Usec > 999999 { + return syserror.EINVAL + } + opts.Stat.Mask = linux.STATX_ATIME | linux.STATX_MTIME + opts.Stat.Atime = linux.StatxTimestamp{ + Sec: times[0].Sec, + Nsec: uint32(times[0].Usec * 1000), + } + opts.Stat.Mtime = linux.StatxTimestamp{ + Sec: times[1].Sec, + Nsec: uint32(times[1].Usec * 1000), + } + return nil +} + +// Utimensat implements Linux syscall utimensat(2). +func Utimensat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + timesAddr := args[2].Pointer() + flags := args[3].Int() + + // Linux requires that the UTIME_OMIT check occur before checking path or + // flags. + var opts vfs.SetStatOptions + if err := populateSetStatOptionsForUtimens(t, timesAddr, &opts); err != nil { + return 0, nil, err + } + if opts.Stat.Mask == 0 { + return 0, nil, nil + } + + if flags&^linux.AT_SYMLINK_NOFOLLOW != 0 { + return 0, nil, syserror.EINVAL + } + + // "If filename is NULL and dfd refers to an open file, then operate on the + // file. Otherwise look up filename, possibly using dfd as a starting + // point." - fs/utimes.c + var path fspath.Path + shouldAllowEmptyPath := allowEmptyPath + if dirfd == linux.AT_FDCWD || pathAddr != 0 { + var err error + path, err = copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + shouldAllowEmptyPath = disallowEmptyPath + } + + return 0, nil, setstatat(t, dirfd, path, shouldAllowEmptyPath, shouldFollowFinalSymlink(flags&linux.AT_SYMLINK_NOFOLLOW == 0), &opts) +} + +func populateSetStatOptionsForUtimens(t *kernel.Task, timesAddr usermem.Addr, opts *vfs.SetStatOptions) error { + if timesAddr == 0 { + opts.Stat.Mask = linux.STATX_ATIME | linux.STATX_MTIME + opts.Stat.Atime.Nsec = linux.UTIME_NOW + opts.Stat.Mtime.Nsec = linux.UTIME_NOW + return nil + } + var times [2]linux.Timespec + if _, err := t.CopyIn(timesAddr, ×); err != nil { + return err + } + if times[0].Nsec != linux.UTIME_OMIT { + if times[0].Nsec != linux.UTIME_NOW && (times[0].Nsec < 0 || times[0].Nsec > 999999999) { + return syserror.EINVAL + } + opts.Stat.Mask |= linux.STATX_ATIME + opts.Stat.Atime = linux.StatxTimestamp{ + Sec: times[0].Sec, + Nsec: uint32(times[0].Nsec), + } + } + if times[1].Nsec != linux.UTIME_OMIT { + if times[1].Nsec != linux.UTIME_NOW && (times[1].Nsec < 0 || times[1].Nsec > 999999999) { + return syserror.EINVAL + } + opts.Stat.Mask |= linux.STATX_MTIME + opts.Stat.Mtime = linux.StatxTimestamp{ + Sec: times[1].Sec, + Nsec: uint32(times[1].Nsec), + } + } + return nil +} + +func setstatat(t *kernel.Task, dirfd int32, path fspath.Path, shouldAllowEmptyPath shouldAllowEmptyPath, shouldFollowFinalSymlink shouldFollowFinalSymlink, opts *vfs.SetStatOptions) error { + root := t.FSContext().RootDirectoryVFS2() + defer root.DecRef(t) + start := root + if !path.Absolute { + if !path.HasComponents() && !bool(shouldAllowEmptyPath) { + return syserror.ENOENT + } + if dirfd == linux.AT_FDCWD { + start = t.FSContext().WorkingDirectoryVFS2() + defer start.DecRef(t) + } else { + dirfile := t.GetFileVFS2(dirfd) + if dirfile == nil { + return syserror.EBADF + } + if !path.HasComponents() { + // Use FileDescription.SetStat() instead of + // VirtualFilesystem.SetStatAt(), since the former may be able + // to use opened file state to expedite the SetStat. + err := dirfile.SetStat(t, *opts) + dirfile.DecRef(t) + return err + } + start = dirfile.VirtualDentry() + start.IncRef() + defer start.DecRef(t) + dirfile.DecRef(t) + } + } + return t.Kernel().VFS().SetStatAt(t, t.Credentials(), &vfs.PathOperation{ + Root: root, + Start: start, + Path: path, + FollowFinalSymlink: bool(shouldFollowFinalSymlink), + }, opts) +} + +func handleSetSizeError(t *kernel.Task, err error) error { + if err == syserror.ErrExceedsFileSizeLimit { + // Convert error to EFBIG and send a SIGXFSZ per setrlimit(2). + t.SendSignal(kernel.SignalInfoNoInfo(linux.SIGXFSZ, t, t)) + return syserror.EFBIG + } + return err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/signal.go b/pkg/sentry/syscalls/linux/vfs2/signal.go new file mode 100644 index 000000000..b89f34cdb --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/signal.go @@ -0,0 +1,100 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/signalfd" + "gvisor.dev/gvisor/pkg/sentry/kernel" + slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// sharedSignalfd is shared between the two calls. +func sharedSignalfd(t *kernel.Task, fd int32, sigset usermem.Addr, sigsetsize uint, flags int32) (uintptr, *kernel.SyscallControl, error) { + // Copy in the signal mask. + mask, err := slinux.CopyInSigSet(t, sigset, sigsetsize) + if err != nil { + return 0, nil, err + } + + // Always check for valid flags, even if not creating. + if flags&^(linux.SFD_NONBLOCK|linux.SFD_CLOEXEC) != 0 { + return 0, nil, syserror.EINVAL + } + + // Is this a change to an existing signalfd? + // + // The spec indicates that this should adjust the mask. + if fd != -1 { + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Is this a signalfd? + if sfd, ok := file.Impl().(*signalfd.SignalFileDescription); ok { + sfd.SetMask(mask) + return 0, nil, nil + } + + // Not a signalfd. + return 0, nil, syserror.EINVAL + } + + fileFlags := uint32(linux.O_RDWR) + if flags&linux.SFD_NONBLOCK != 0 { + fileFlags |= linux.O_NONBLOCK + } + + // Create a new file. + vfsObj := t.Kernel().VFS() + file, err := signalfd.New(vfsObj, t, mask, fileFlags) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + + // Create a new descriptor. + fd, err = t.NewFDFromVFS2(0, file, kernel.FDFlags{ + CloseOnExec: flags&linux.SFD_CLOEXEC != 0, + }) + if err != nil { + return 0, nil, err + } + + // Done. + return uintptr(fd), nil, nil +} + +// Signalfd implements the linux syscall signalfd(2). +func Signalfd(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + sigset := args[1].Pointer() + sigsetsize := args[2].SizeT() + return sharedSignalfd(t, fd, sigset, sigsetsize, 0) +} + +// Signalfd4 implements the linux syscall signalfd4(2). +func Signalfd4(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + sigset := args[1].Pointer() + sigsetsize := args[2].SizeT() + flags := args[3].Int() + return sharedSignalfd(t, fd, sigset, sigsetsize, flags) +} diff --git a/pkg/sentry/syscalls/linux/vfs2/socket.go b/pkg/sentry/syscalls/linux/vfs2/socket.go new file mode 100644 index 000000000..4a68c64f3 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/socket.go @@ -0,0 +1,1144 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "time" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/binary" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/sentry/socket" + "gvisor.dev/gvisor/pkg/sentry/socket/control" + "gvisor.dev/gvisor/pkg/sentry/socket/unix/transport" + slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserr" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/tools/go_marshal/marshal" + "gvisor.dev/gvisor/tools/go_marshal/primitive" +) + +// minListenBacklog is the minimum reasonable backlog for listening sockets. +const minListenBacklog = 8 + +// maxListenBacklog is the maximum allowed backlog for listening sockets. +const maxListenBacklog = 1024 + +// maxAddrLen is the maximum socket address length we're willing to accept. +const maxAddrLen = 200 + +// maxOptLen is the maximum sockopt parameter length we're willing to accept. +const maxOptLen = 1024 * 8 + +// maxControlLen is the maximum length of the msghdr.msg_control buffer we're +// willing to accept. Note that this limit is smaller than Linux, which allows +// buffers upto INT_MAX. +const maxControlLen = 10 * 1024 * 1024 + +// nameLenOffset is the offset from the start of the MessageHeader64 struct to +// the NameLen field. +const nameLenOffset = 8 + +// controlLenOffset is the offset form the start of the MessageHeader64 struct +// to the ControlLen field. +const controlLenOffset = 40 + +// flagsOffset is the offset form the start of the MessageHeader64 struct +// to the Flags field. +const flagsOffset = 48 + +const sizeOfInt32 = 4 + +// messageHeader64Len is the length of a MessageHeader64 struct. +var messageHeader64Len = uint64(binary.Size(MessageHeader64{})) + +// multipleMessageHeader64Len is the length of a multipeMessageHeader64 struct. +var multipleMessageHeader64Len = uint64(binary.Size(multipleMessageHeader64{})) + +// baseRecvFlags are the flags that are accepted across recvmsg(2), +// recvmmsg(2), and recvfrom(2). +const baseRecvFlags = linux.MSG_OOB | linux.MSG_DONTROUTE | linux.MSG_DONTWAIT | linux.MSG_NOSIGNAL | linux.MSG_WAITALL | linux.MSG_TRUNC | linux.MSG_CTRUNC + +// MessageHeader64 is the 64-bit representation of the msghdr struct used in +// the recvmsg and sendmsg syscalls. +type MessageHeader64 struct { + // Name is the optional pointer to a network address buffer. + Name uint64 + + // NameLen is the length of the buffer pointed to by Name. + NameLen uint32 + _ uint32 + + // Iov is a pointer to an array of io vectors that describe the memory + // locations involved in the io operation. + Iov uint64 + + // IovLen is the length of the array pointed to by Iov. + IovLen uint64 + + // Control is the optional pointer to ancillary control data. + Control uint64 + + // ControlLen is the length of the data pointed to by Control. + ControlLen uint64 + + // Flags on the sent/received message. + Flags int32 + _ int32 +} + +// multipleMessageHeader64 is the 64-bit representation of the mmsghdr struct used in +// the recvmmsg and sendmmsg syscalls. +type multipleMessageHeader64 struct { + msgHdr MessageHeader64 + msgLen uint32 + _ int32 +} + +// CopyInMessageHeader64 copies a message header from user to kernel memory. +func CopyInMessageHeader64(t *kernel.Task, addr usermem.Addr, msg *MessageHeader64) error { + b := t.CopyScratchBuffer(52) + if _, err := t.CopyInBytes(addr, b); err != nil { + return err + } + + msg.Name = usermem.ByteOrder.Uint64(b[0:]) + msg.NameLen = usermem.ByteOrder.Uint32(b[8:]) + msg.Iov = usermem.ByteOrder.Uint64(b[16:]) + msg.IovLen = usermem.ByteOrder.Uint64(b[24:]) + msg.Control = usermem.ByteOrder.Uint64(b[32:]) + msg.ControlLen = usermem.ByteOrder.Uint64(b[40:]) + msg.Flags = int32(usermem.ByteOrder.Uint32(b[48:])) + + return nil +} + +// CaptureAddress allocates memory for and copies a socket address structure +// from the untrusted address space range. +func CaptureAddress(t *kernel.Task, addr usermem.Addr, addrlen uint32) ([]byte, error) { + if addrlen > maxAddrLen { + return nil, syserror.EINVAL + } + + addrBuf := make([]byte, addrlen) + if _, err := t.CopyInBytes(addr, addrBuf); err != nil { + return nil, err + } + + return addrBuf, nil +} + +// writeAddress writes a sockaddr structure and its length to an output buffer +// in the unstrusted address space range. If the address is bigger than the +// buffer, it is truncated. +func writeAddress(t *kernel.Task, addr interface{}, addrLen uint32, addrPtr usermem.Addr, addrLenPtr usermem.Addr) error { + // Get the buffer length. + var bufLen uint32 + if _, err := t.CopyIn(addrLenPtr, &bufLen); err != nil { + return err + } + + if int32(bufLen) < 0 { + return syserror.EINVAL + } + + // Write the length unconditionally. + if _, err := t.CopyOut(addrLenPtr, addrLen); err != nil { + return err + } + + if addr == nil { + return nil + } + + if bufLen > addrLen { + bufLen = addrLen + } + + // Copy as much of the address as will fit in the buffer. + encodedAddr := binary.Marshal(nil, usermem.ByteOrder, addr) + if bufLen > uint32(len(encodedAddr)) { + bufLen = uint32(len(encodedAddr)) + } + _, err := t.CopyOutBytes(addrPtr, encodedAddr[:int(bufLen)]) + return err +} + +// Socket implements the linux syscall socket(2). +func Socket(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + domain := int(args[0].Int()) + stype := args[1].Int() + protocol := int(args[2].Int()) + + // Check and initialize the flags. + if stype & ^(0xf|linux.SOCK_NONBLOCK|linux.SOCK_CLOEXEC) != 0 { + return 0, nil, syserror.EINVAL + } + + // Create the new socket. + s, e := socket.NewVFS2(t, domain, linux.SockType(stype&0xf), protocol) + if e != nil { + return 0, nil, e.ToError() + } + defer s.DecRef(t) + + if err := s.SetStatusFlags(t, t.Credentials(), uint32(stype&linux.SOCK_NONBLOCK)); err != nil { + return 0, nil, err + } + + fd, err := t.NewFDFromVFS2(0, s, kernel.FDFlags{ + CloseOnExec: stype&linux.SOCK_CLOEXEC != 0, + }) + if err != nil { + return 0, nil, err + } + + return uintptr(fd), nil, nil +} + +// SocketPair implements the linux syscall socketpair(2). +func SocketPair(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + domain := int(args[0].Int()) + stype := args[1].Int() + protocol := int(args[2].Int()) + addr := args[3].Pointer() + + // Check and initialize the flags. + if stype & ^(0xf|linux.SOCK_NONBLOCK|linux.SOCK_CLOEXEC) != 0 { + return 0, nil, syserror.EINVAL + } + + // Create the socket pair. + s1, s2, e := socket.PairVFS2(t, domain, linux.SockType(stype&0xf), protocol) + if e != nil { + return 0, nil, e.ToError() + } + // Adding to the FD table will cause an extra reference to be acquired. + defer s1.DecRef(t) + defer s2.DecRef(t) + + nonblocking := uint32(stype & linux.SOCK_NONBLOCK) + if err := s1.SetStatusFlags(t, t.Credentials(), nonblocking); err != nil { + return 0, nil, err + } + if err := s2.SetStatusFlags(t, t.Credentials(), nonblocking); err != nil { + return 0, nil, err + } + + // Create the FDs for the sockets. + flags := kernel.FDFlags{ + CloseOnExec: stype&linux.SOCK_CLOEXEC != 0, + } + fds, err := t.NewFDsVFS2(0, []*vfs.FileDescription{s1, s2}, flags) + if err != nil { + return 0, nil, err + } + + if _, err := t.CopyOut(addr, fds); err != nil { + for _, fd := range fds { + if _, file := t.FDTable().Remove(fd); file != nil { + file.DecRef(t) + } + } + return 0, nil, err + } + + return 0, nil, nil +} + +// Connect implements the linux syscall connect(2). +func Connect(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + addrlen := args[2].Uint() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Capture address and call syscall implementation. + a, err := CaptureAddress(t, addr, addrlen) + if err != nil { + return 0, nil, err + } + + blocking := (file.StatusFlags() & linux.SOCK_NONBLOCK) == 0 + return 0, nil, syserror.ConvertIntr(s.Connect(t, a, blocking).ToError(), kernel.ERESTARTSYS) +} + +// accept is the implementation of the accept syscall. It is called by accept +// and accept4 syscall handlers. +func accept(t *kernel.Task, fd int32, addr usermem.Addr, addrLen usermem.Addr, flags int) (uintptr, error) { + // Check that no unsupported flags are passed in. + if flags & ^(linux.SOCK_NONBLOCK|linux.SOCK_CLOEXEC) != 0 { + return 0, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, syserror.ENOTSOCK + } + + // Call the syscall implementation for this socket, then copy the + // output address if one is specified. + blocking := (file.StatusFlags() & linux.SOCK_NONBLOCK) == 0 + + peerRequested := addrLen != 0 + nfd, peer, peerLen, e := s.Accept(t, peerRequested, flags, blocking) + if e != nil { + return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS) + } + if peerRequested { + // NOTE(magi): Linux does not give you an error if it can't + // write the data back out so neither do we. + if err := writeAddress(t, peer, peerLen, addr, addrLen); err == syserror.EINVAL { + return 0, err + } + } + return uintptr(nfd), nil +} + +// Accept4 implements the linux syscall accept4(2). +func Accept4(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + addrlen := args[2].Pointer() + flags := int(args[3].Int()) + + n, err := accept(t, fd, addr, addrlen, flags) + return n, nil, err +} + +// Accept implements the linux syscall accept(2). +func Accept(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + addrlen := args[2].Pointer() + + n, err := accept(t, fd, addr, addrlen, 0) + return n, nil, err +} + +// Bind implements the linux syscall bind(2). +func Bind(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + addrlen := args[2].Uint() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Capture address and call syscall implementation. + a, err := CaptureAddress(t, addr, addrlen) + if err != nil { + return 0, nil, err + } + + return 0, nil, s.Bind(t, a).ToError() +} + +// Listen implements the linux syscall listen(2). +func Listen(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + backlog := args[1].Int() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Per Linux, the backlog is silently capped to reasonable values. + if backlog <= 0 { + backlog = minListenBacklog + } + if backlog > maxListenBacklog { + backlog = maxListenBacklog + } + + return 0, nil, s.Listen(t, int(backlog)).ToError() +} + +// Shutdown implements the linux syscall shutdown(2). +func Shutdown(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + how := args[1].Int() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Validate how, then call syscall implementation. + switch how { + case linux.SHUT_RD, linux.SHUT_WR, linux.SHUT_RDWR: + default: + return 0, nil, syserror.EINVAL + } + + return 0, nil, s.Shutdown(t, int(how)).ToError() +} + +// GetSockOpt implements the linux syscall getsockopt(2). +func GetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + level := args[1].Int() + name := args[2].Int() + optValAddr := args[3].Pointer() + optLenAddr := args[4].Pointer() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Read the length. Reject negative values. + optLen := int32(0) + if _, err := t.CopyIn(optLenAddr, &optLen); err != nil { + return 0, nil, err + } + if optLen < 0 { + return 0, nil, syserror.EINVAL + } + + // Call syscall implementation then copy both value and value len out. + v, e := getSockOpt(t, s, int(level), int(name), optValAddr, int(optLen)) + if e != nil { + return 0, nil, e.ToError() + } + + vLen := int32(binary.Size(v)) + if _, err := t.CopyOut(optLenAddr, vLen); err != nil { + return 0, nil, err + } + + if v != nil { + if _, err := v.CopyOut(t, optValAddr); err != nil { + return 0, nil, err + } + } + + return 0, nil, nil +} + +// getSockOpt tries to handle common socket options, or dispatches to a specific +// socket implementation. +func getSockOpt(t *kernel.Task, s socket.SocketVFS2, level, name int, optValAddr usermem.Addr, len int) (marshal.Marshallable, *syserr.Error) { + if level == linux.SOL_SOCKET { + switch name { + case linux.SO_TYPE, linux.SO_DOMAIN, linux.SO_PROTOCOL: + if len < sizeOfInt32 { + return nil, syserr.ErrInvalidArgument + } + } + + switch name { + case linux.SO_TYPE: + _, skType, _ := s.Type() + v := primitive.Int32(skType) + return &v, nil + case linux.SO_DOMAIN: + family, _, _ := s.Type() + v := primitive.Int32(family) + return &v, nil + case linux.SO_PROTOCOL: + _, _, protocol := s.Type() + v := primitive.Int32(protocol) + return &v, nil + } + } + + return s.GetSockOpt(t, level, name, optValAddr, len) +} + +// SetSockOpt implements the linux syscall setsockopt(2). +// +// Note that unlike Linux, enabling SO_PASSCRED does not autobind the socket. +func SetSockOpt(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + level := args[1].Int() + name := args[2].Int() + optValAddr := args[3].Pointer() + optLen := args[4].Int() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + if optLen < 0 { + return 0, nil, syserror.EINVAL + } + if optLen > maxOptLen { + return 0, nil, syserror.EINVAL + } + buf := t.CopyScratchBuffer(int(optLen)) + if _, err := t.CopyInBytes(optValAddr, buf); err != nil { + return 0, nil, err + } + + // Call syscall implementation. + if err := s.SetSockOpt(t, int(level), int(name), buf); err != nil { + return 0, nil, err.ToError() + } + + return 0, nil, nil +} + +// GetSockName implements the linux syscall getsockname(2). +func GetSockName(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + addrlen := args[2].Pointer() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Get the socket name and copy it to the caller. + v, vl, err := s.GetSockName(t) + if err != nil { + return 0, nil, err.ToError() + } + + return 0, nil, writeAddress(t, v, vl, addr, addrlen) +} + +// GetPeerName implements the linux syscall getpeername(2). +func GetPeerName(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + addr := args[1].Pointer() + addrlen := args[2].Pointer() + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Get the socket peer name and copy it to the caller. + v, vl, err := s.GetPeerName(t) + if err != nil { + return 0, nil, err.ToError() + } + + return 0, nil, writeAddress(t, v, vl, addr, addrlen) +} + +// RecvMsg implements the linux syscall recvmsg(2). +func RecvMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + msgPtr := args[1].Pointer() + flags := args[2].Int() + + if t.Arch().Width() != 8 { + // We only handle 64-bit for now. + return 0, nil, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Reject flags that we don't handle yet. + if flags & ^(baseRecvFlags|linux.MSG_PEEK|linux.MSG_CMSG_CLOEXEC|linux.MSG_ERRQUEUE) != 0 { + return 0, nil, syserror.EINVAL + } + + if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 { + flags |= linux.MSG_DONTWAIT + } + + var haveDeadline bool + var deadline ktime.Time + if dl := s.RecvTimeout(); dl > 0 { + deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond) + haveDeadline = true + } else if dl < 0 { + flags |= linux.MSG_DONTWAIT + } + + n, err := recvSingleMsg(t, s, msgPtr, flags, haveDeadline, deadline) + return n, nil, err +} + +// RecvMMsg implements the linux syscall recvmmsg(2). +func RecvMMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + msgPtr := args[1].Pointer() + vlen := args[2].Uint() + flags := args[3].Int() + toPtr := args[4].Pointer() + + if t.Arch().Width() != 8 { + // We only handle 64-bit for now. + return 0, nil, syserror.EINVAL + } + + // Reject flags that we don't handle yet. + if flags & ^(baseRecvFlags|linux.MSG_CMSG_CLOEXEC|linux.MSG_ERRQUEUE) != 0 { + return 0, nil, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 { + flags |= linux.MSG_DONTWAIT + } + + var haveDeadline bool + var deadline ktime.Time + if toPtr != 0 { + var ts linux.Timespec + if _, err := ts.CopyIn(t, toPtr); err != nil { + return 0, nil, err + } + if !ts.Valid() { + return 0, nil, syserror.EINVAL + } + deadline = t.Kernel().MonotonicClock().Now().Add(ts.ToDuration()) + haveDeadline = true + } + + if !haveDeadline { + if dl := s.RecvTimeout(); dl > 0 { + deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond) + haveDeadline = true + } else if dl < 0 { + flags |= linux.MSG_DONTWAIT + } + } + + var count uint32 + var err error + for i := uint64(0); i < uint64(vlen); i++ { + mp, ok := msgPtr.AddLength(i * multipleMessageHeader64Len) + if !ok { + return 0, nil, syserror.EFAULT + } + var n uintptr + if n, err = recvSingleMsg(t, s, mp, flags, haveDeadline, deadline); err != nil { + break + } + + // Copy the received length to the caller. + lp, ok := mp.AddLength(messageHeader64Len) + if !ok { + return 0, nil, syserror.EFAULT + } + if _, err = t.CopyOut(lp, uint32(n)); err != nil { + break + } + count++ + } + + if count == 0 { + return 0, nil, err + } + return uintptr(count), nil, nil +} + +func recvSingleMsg(t *kernel.Task, s socket.SocketVFS2, msgPtr usermem.Addr, flags int32, haveDeadline bool, deadline ktime.Time) (uintptr, error) { + // Capture the message header and io vectors. + var msg MessageHeader64 + if err := CopyInMessageHeader64(t, msgPtr, &msg); err != nil { + return 0, err + } + + if msg.IovLen > linux.UIO_MAXIOV { + return 0, syserror.EMSGSIZE + } + dst, err := t.IovecsIOSequence(usermem.Addr(msg.Iov), int(msg.IovLen), usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, err + } + + // FIXME(b/63594852): Pretend we have an empty error queue. + if flags&linux.MSG_ERRQUEUE != 0 { + return 0, syserror.EAGAIN + } + + // Fast path when no control message nor name buffers are provided. + if msg.ControlLen == 0 && msg.NameLen == 0 { + n, mflags, _, _, cms, err := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, false, 0) + if err != nil { + return 0, syserror.ConvertIntr(err.ToError(), kernel.ERESTARTSYS) + } + if !cms.Unix.Empty() { + mflags |= linux.MSG_CTRUNC + cms.Release(t) + } + + if int(msg.Flags) != mflags { + // Copy out the flags to the caller. + if _, err := t.CopyOut(msgPtr+flagsOffset, int32(mflags)); err != nil { + return 0, err + } + } + + return uintptr(n), nil + } + + if msg.ControlLen > maxControlLen { + return 0, syserror.ENOBUFS + } + n, mflags, sender, senderLen, cms, e := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, msg.NameLen != 0, msg.ControlLen) + if e != nil { + return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS) + } + defer cms.Release(t) + + controlData := make([]byte, 0, msg.ControlLen) + controlData = control.PackControlMessages(t, cms, controlData) + + if cr, ok := s.(transport.Credentialer); ok && cr.Passcred() { + creds, _ := cms.Unix.Credentials.(control.SCMCredentials) + controlData, mflags = control.PackCredentials(t, creds, controlData, mflags) + } + + if cms.Unix.Rights != nil { + controlData, mflags = control.PackRightsVFS2(t, cms.Unix.Rights.(control.SCMRightsVFS2), flags&linux.MSG_CMSG_CLOEXEC != 0, controlData, mflags) + } + + // Copy the address to the caller. + if msg.NameLen != 0 { + if err := writeAddress(t, sender, senderLen, usermem.Addr(msg.Name), usermem.Addr(msgPtr+nameLenOffset)); err != nil { + return 0, err + } + } + + // Copy the control data to the caller. + if _, err := t.CopyOut(msgPtr+controlLenOffset, uint64(len(controlData))); err != nil { + return 0, err + } + if len(controlData) > 0 { + if _, err := t.CopyOut(usermem.Addr(msg.Control), controlData); err != nil { + return 0, err + } + } + + // Copy out the flags to the caller. + if _, err := t.CopyOut(msgPtr+flagsOffset, int32(mflags)); err != nil { + return 0, err + } + + return uintptr(n), nil +} + +// recvFrom is the implementation of the recvfrom syscall. It is called by +// recvfrom and recv syscall handlers. +func recvFrom(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flags int32, namePtr usermem.Addr, nameLenPtr usermem.Addr) (uintptr, error) { + if int(bufLen) < 0 { + return 0, syserror.EINVAL + } + + // Reject flags that we don't handle yet. + if flags & ^(baseRecvFlags|linux.MSG_PEEK|linux.MSG_CONFIRM) != 0 { + return 0, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, syserror.ENOTSOCK + } + + if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 { + flags |= linux.MSG_DONTWAIT + } + + dst, err := t.SingleIOSequence(bufPtr, int(bufLen), usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, err + } + + var haveDeadline bool + var deadline ktime.Time + if dl := s.RecvTimeout(); dl > 0 { + deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond) + haveDeadline = true + } else if dl < 0 { + flags |= linux.MSG_DONTWAIT + } + + n, _, sender, senderLen, cm, e := s.RecvMsg(t, dst, int(flags), haveDeadline, deadline, nameLenPtr != 0, 0) + cm.Release(t) + if e != nil { + return 0, syserror.ConvertIntr(e.ToError(), kernel.ERESTARTSYS) + } + + // Copy the address to the caller. + if nameLenPtr != 0 { + if err := writeAddress(t, sender, senderLen, namePtr, nameLenPtr); err != nil { + return 0, err + } + } + + return uintptr(n), nil +} + +// RecvFrom implements the linux syscall recvfrom(2). +func RecvFrom(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + bufPtr := args[1].Pointer() + bufLen := args[2].Uint64() + flags := args[3].Int() + namePtr := args[4].Pointer() + nameLenPtr := args[5].Pointer() + + n, err := recvFrom(t, fd, bufPtr, bufLen, flags, namePtr, nameLenPtr) + return n, nil, err +} + +// SendMsg implements the linux syscall sendmsg(2). +func SendMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + msgPtr := args[1].Pointer() + flags := args[2].Int() + + if t.Arch().Width() != 8 { + // We only handle 64-bit for now. + return 0, nil, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Reject flags that we don't handle yet. + if flags & ^(linux.MSG_DONTWAIT|linux.MSG_EOR|linux.MSG_MORE|linux.MSG_NOSIGNAL) != 0 { + return 0, nil, syserror.EINVAL + } + + if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 { + flags |= linux.MSG_DONTWAIT + } + + n, err := sendSingleMsg(t, s, file, msgPtr, flags) + return n, nil, err +} + +// SendMMsg implements the linux syscall sendmmsg(2). +func SendMMsg(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + msgPtr := args[1].Pointer() + vlen := args[2].Uint() + flags := args[3].Int() + + if t.Arch().Width() != 8 { + // We only handle 64-bit for now. + return 0, nil, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, nil, syserror.ENOTSOCK + } + + // Reject flags that we don't handle yet. + if flags & ^(linux.MSG_DONTWAIT|linux.MSG_EOR|linux.MSG_MORE|linux.MSG_NOSIGNAL) != 0 { + return 0, nil, syserror.EINVAL + } + + if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 { + flags |= linux.MSG_DONTWAIT + } + + var count uint32 + var err error + for i := uint64(0); i < uint64(vlen); i++ { + mp, ok := msgPtr.AddLength(i * multipleMessageHeader64Len) + if !ok { + return 0, nil, syserror.EFAULT + } + var n uintptr + if n, err = sendSingleMsg(t, s, file, mp, flags); err != nil { + break + } + + // Copy the received length to the caller. + lp, ok := mp.AddLength(messageHeader64Len) + if !ok { + return 0, nil, syserror.EFAULT + } + if _, err = t.CopyOut(lp, uint32(n)); err != nil { + break + } + count++ + } + + if count == 0 { + return 0, nil, err + } + return uintptr(count), nil, nil +} + +func sendSingleMsg(t *kernel.Task, s socket.SocketVFS2, file *vfs.FileDescription, msgPtr usermem.Addr, flags int32) (uintptr, error) { + // Capture the message header. + var msg MessageHeader64 + if err := CopyInMessageHeader64(t, msgPtr, &msg); err != nil { + return 0, err + } + + var controlData []byte + if msg.ControlLen > 0 { + // Put an upper bound to prevent large allocations. + if msg.ControlLen > maxControlLen { + return 0, syserror.ENOBUFS + } + controlData = make([]byte, msg.ControlLen) + if _, err := t.CopyIn(usermem.Addr(msg.Control), &controlData); err != nil { + return 0, err + } + } + + // Read the destination address if one is specified. + var to []byte + if msg.NameLen != 0 { + var err error + to, err = CaptureAddress(t, usermem.Addr(msg.Name), msg.NameLen) + if err != nil { + return 0, err + } + } + + // Read data then call the sendmsg implementation. + if msg.IovLen > linux.UIO_MAXIOV { + return 0, syserror.EMSGSIZE + } + src, err := t.IovecsIOSequence(usermem.Addr(msg.Iov), int(msg.IovLen), usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, err + } + + controlMessages, err := control.Parse(t, s, controlData) + if err != nil { + return 0, err + } + + var haveDeadline bool + var deadline ktime.Time + if dl := s.SendTimeout(); dl > 0 { + deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond) + haveDeadline = true + } else if dl < 0 { + flags |= linux.MSG_DONTWAIT + } + + // Call the syscall implementation. + n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, controlMessages) + err = slinux.HandleIOErrorVFS2(t, n != 0, e.ToError(), kernel.ERESTARTSYS, "sendmsg", file) + if err != nil { + controlMessages.Release(t) + } + return uintptr(n), err +} + +// sendTo is the implementation of the sendto syscall. It is called by sendto +// and send syscall handlers. +func sendTo(t *kernel.Task, fd int32, bufPtr usermem.Addr, bufLen uint64, flags int32, namePtr usermem.Addr, nameLen uint32) (uintptr, error) { + bl := int(bufLen) + if bl < 0 { + return 0, syserror.EINVAL + } + + // Get socket from the file descriptor. + file := t.GetFileVFS2(fd) + if file == nil { + return 0, syserror.EBADF + } + defer file.DecRef(t) + + // Extract the socket. + s, ok := file.Impl().(socket.SocketVFS2) + if !ok { + return 0, syserror.ENOTSOCK + } + + if (file.StatusFlags() & linux.SOCK_NONBLOCK) != 0 { + flags |= linux.MSG_DONTWAIT + } + + // Read the destination address if one is specified. + var to []byte + var err error + if namePtr != 0 { + to, err = CaptureAddress(t, namePtr, nameLen) + if err != nil { + return 0, err + } + } + + src, err := t.SingleIOSequence(bufPtr, bl, usermem.IOOpts{ + AddressSpaceActive: true, + }) + if err != nil { + return 0, err + } + + var haveDeadline bool + var deadline ktime.Time + if dl := s.SendTimeout(); dl > 0 { + deadline = t.Kernel().MonotonicClock().Now().Add(time.Duration(dl) * time.Nanosecond) + haveDeadline = true + } else if dl < 0 { + flags |= linux.MSG_DONTWAIT + } + + // Call the syscall implementation. + n, e := s.SendMsg(t, src, to, int(flags), haveDeadline, deadline, socket.ControlMessages{Unix: control.New(t, s, nil)}) + return uintptr(n), slinux.HandleIOErrorVFS2(t, n != 0, e.ToError(), kernel.ERESTARTSYS, "sendto", file) +} + +// SendTo implements the linux syscall sendto(2). +func SendTo(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + bufPtr := args[1].Pointer() + bufLen := args[2].Uint64() + flags := args[3].Int() + namePtr := args[4].Pointer() + nameLen := args[5].Uint() + + n, err := sendTo(t, fd, bufPtr, bufLen, flags, namePtr, nameLen) + return n, nil, err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/splice.go b/pkg/sentry/syscalls/linux/vfs2/splice.go new file mode 100644 index 000000000..75bfa2c79 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/splice.go @@ -0,0 +1,490 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "io" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/pipe" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" + "gvisor.dev/gvisor/pkg/waiter" +) + +// Splice implements Linux syscall splice(2). +func Splice(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + inFD := args[0].Int() + inOffsetPtr := args[1].Pointer() + outFD := args[2].Int() + outOffsetPtr := args[3].Pointer() + count := int64(args[4].SizeT()) + flags := args[5].Int() + + if count == 0 { + return 0, nil, nil + } + if count > int64(kernel.MAX_RW_COUNT) { + count = int64(kernel.MAX_RW_COUNT) + } + + // Check for invalid flags. + if flags&^(linux.SPLICE_F_MOVE|linux.SPLICE_F_NONBLOCK|linux.SPLICE_F_MORE|linux.SPLICE_F_GIFT) != 0 { + return 0, nil, syserror.EINVAL + } + + // Get file descriptions. + inFile := t.GetFileVFS2(inFD) + if inFile == nil { + return 0, nil, syserror.EBADF + } + defer inFile.DecRef(t) + outFile := t.GetFileVFS2(outFD) + if outFile == nil { + return 0, nil, syserror.EBADF + } + defer outFile.DecRef(t) + + // Check that both files support the required directionality. + if !inFile.IsReadable() || !outFile.IsWritable() { + return 0, nil, syserror.EBADF + } + + // The operation is non-blocking if anything is non-blocking. + // + // N.B. This is a rather simplistic heuristic that avoids some + // poor edge case behavior since the exact semantics here are + // underspecified and vary between versions of Linux itself. + nonBlock := ((inFile.StatusFlags()|outFile.StatusFlags())&linux.O_NONBLOCK != 0) || (flags&linux.SPLICE_F_NONBLOCK != 0) + + // At least one file description must represent a pipe. + inPipeFD, inIsPipe := inFile.Impl().(*pipe.VFSPipeFD) + outPipeFD, outIsPipe := outFile.Impl().(*pipe.VFSPipeFD) + if !inIsPipe && !outIsPipe { + return 0, nil, syserror.EINVAL + } + + // Copy in offsets. + inOffset := int64(-1) + if inOffsetPtr != 0 { + if inIsPipe { + return 0, nil, syserror.ESPIPE + } + if inFile.Options().DenyPRead { + return 0, nil, syserror.EINVAL + } + if _, err := t.CopyIn(inOffsetPtr, &inOffset); err != nil { + return 0, nil, err + } + if inOffset < 0 { + return 0, nil, syserror.EINVAL + } + } + outOffset := int64(-1) + if outOffsetPtr != 0 { + if outIsPipe { + return 0, nil, syserror.ESPIPE + } + if outFile.Options().DenyPWrite { + return 0, nil, syserror.EINVAL + } + if _, err := t.CopyIn(outOffsetPtr, &outOffset); err != nil { + return 0, nil, err + } + if outOffset < 0 { + return 0, nil, syserror.EINVAL + } + } + + // Move data. + var ( + n int64 + err error + ) + dw := dualWaiter{ + inFile: inFile, + outFile: outFile, + } + defer dw.destroy() + for { + // If both input and output are pipes, delegate to the pipe + // implementation. Otherwise, exactly one end is a pipe, which + // we ensure is consistently ordered after the non-pipe FD's + // locks by passing the pipe FD as usermem.IO to the non-pipe + // end. + switch { + case inIsPipe && outIsPipe: + n, err = pipe.Splice(t, outPipeFD, inPipeFD, count) + case inIsPipe: + if outOffset != -1 { + n, err = outFile.PWrite(t, inPipeFD.IOSequence(count), outOffset, vfs.WriteOptions{}) + outOffset += n + } else { + n, err = outFile.Write(t, inPipeFD.IOSequence(count), vfs.WriteOptions{}) + } + case outIsPipe: + if inOffset != -1 { + n, err = inFile.PRead(t, outPipeFD.IOSequence(count), inOffset, vfs.ReadOptions{}) + inOffset += n + } else { + n, err = inFile.Read(t, outPipeFD.IOSequence(count), vfs.ReadOptions{}) + } + default: + panic("not possible") + } + + if n != 0 || err != syserror.ErrWouldBlock || nonBlock { + break + } + if err = dw.waitForBoth(t); err != nil { + break + } + } + + // Copy updated offsets out. + if inOffsetPtr != 0 { + if _, err := t.CopyOut(inOffsetPtr, &inOffset); err != nil { + return 0, nil, err + } + } + if outOffsetPtr != 0 { + if _, err := t.CopyOut(outOffsetPtr, &outOffset); err != nil { + return 0, nil, err + } + } + + if n == 0 { + return 0, nil, err + } + + // On Linux, inotify behavior is not very consistent with splice(2). We try + // our best to emulate Linux for very basic calls to splice, where for some + // reason, events are generated for output files, but not input files. + outFile.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + return uintptr(n), nil, nil +} + +// Tee implements Linux syscall tee(2). +func Tee(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + inFD := args[0].Int() + outFD := args[1].Int() + count := int64(args[2].SizeT()) + flags := args[3].Int() + + if count == 0 { + return 0, nil, nil + } + if count > int64(kernel.MAX_RW_COUNT) { + count = int64(kernel.MAX_RW_COUNT) + } + + // Check for invalid flags. + if flags&^(linux.SPLICE_F_MOVE|linux.SPLICE_F_NONBLOCK|linux.SPLICE_F_MORE|linux.SPLICE_F_GIFT) != 0 { + return 0, nil, syserror.EINVAL + } + + // Get file descriptions. + inFile := t.GetFileVFS2(inFD) + if inFile == nil { + return 0, nil, syserror.EBADF + } + defer inFile.DecRef(t) + outFile := t.GetFileVFS2(outFD) + if outFile == nil { + return 0, nil, syserror.EBADF + } + defer outFile.DecRef(t) + + // Check that both files support the required directionality. + if !inFile.IsReadable() || !outFile.IsWritable() { + return 0, nil, syserror.EBADF + } + + // The operation is non-blocking if anything is non-blocking. + // + // N.B. This is a rather simplistic heuristic that avoids some + // poor edge case behavior since the exact semantics here are + // underspecified and vary between versions of Linux itself. + nonBlock := ((inFile.StatusFlags()|outFile.StatusFlags())&linux.O_NONBLOCK != 0) || (flags&linux.SPLICE_F_NONBLOCK != 0) + + // Both file descriptions must represent pipes. + inPipeFD, inIsPipe := inFile.Impl().(*pipe.VFSPipeFD) + outPipeFD, outIsPipe := outFile.Impl().(*pipe.VFSPipeFD) + if !inIsPipe || !outIsPipe { + return 0, nil, syserror.EINVAL + } + + // Copy data. + var ( + n int64 + err error + ) + dw := dualWaiter{ + inFile: inFile, + outFile: outFile, + } + defer dw.destroy() + for { + n, err = pipe.Tee(t, outPipeFD, inPipeFD, count) + if n != 0 || err != syserror.ErrWouldBlock || nonBlock { + break + } + if err = dw.waitForBoth(t); err != nil { + break + } + } + if n == 0 { + return 0, nil, err + } + outFile.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + return uintptr(n), nil, nil +} + +// Sendfile implements linux system call sendfile(2). +func Sendfile(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + outFD := args[0].Int() + inFD := args[1].Int() + offsetAddr := args[2].Pointer() + count := int64(args[3].SizeT()) + + inFile := t.GetFileVFS2(inFD) + if inFile == nil { + return 0, nil, syserror.EBADF + } + defer inFile.DecRef(t) + if !inFile.IsReadable() { + return 0, nil, syserror.EBADF + } + + outFile := t.GetFileVFS2(outFD) + if outFile == nil { + return 0, nil, syserror.EBADF + } + defer outFile.DecRef(t) + if !outFile.IsWritable() { + return 0, nil, syserror.EBADF + } + + // Verify that the outFile Append flag is not set. + if outFile.StatusFlags()&linux.O_APPEND != 0 { + return 0, nil, syserror.EINVAL + } + + // Verify that inFile is a regular file or block device. This is a + // requirement; the same check appears in Linux + // (fs/splice.c:splice_direct_to_actor). + if stat, err := inFile.Stat(t, vfs.StatOptions{Mask: linux.STATX_TYPE}); err != nil { + return 0, nil, err + } else if stat.Mask&linux.STATX_TYPE == 0 || + (stat.Mode&linux.S_IFMT != linux.S_IFREG && stat.Mode&linux.S_IFMT != linux.S_IFBLK) { + return 0, nil, syserror.EINVAL + } + + // Copy offset if it exists. + offset := int64(-1) + if offsetAddr != 0 { + if inFile.Options().DenyPRead { + return 0, nil, syserror.ESPIPE + } + if _, err := t.CopyIn(offsetAddr, &offset); err != nil { + return 0, nil, err + } + if offset < 0 { + return 0, nil, syserror.EINVAL + } + if offset+count < 0 { + return 0, nil, syserror.EINVAL + } + } + + // Validate count. This must come after offset checks. + if count < 0 { + return 0, nil, syserror.EINVAL + } + if count == 0 { + return 0, nil, nil + } + if count > int64(kernel.MAX_RW_COUNT) { + count = int64(kernel.MAX_RW_COUNT) + } + + // Copy data. + var ( + n int64 + err error + ) + dw := dualWaiter{ + inFile: inFile, + outFile: outFile, + } + defer dw.destroy() + outPipeFD, outIsPipe := outFile.Impl().(*pipe.VFSPipeFD) + // Reading from input file should never block, since it is regular or + // block device. We only need to check if writing to the output file + // can block. + nonBlock := outFile.StatusFlags()&linux.O_NONBLOCK != 0 + if outIsPipe { + for n < count { + var spliceN int64 + if offset != -1 { + spliceN, err = inFile.PRead(t, outPipeFD.IOSequence(count), offset, vfs.ReadOptions{}) + offset += spliceN + } else { + spliceN, err = inFile.Read(t, outPipeFD.IOSequence(count), vfs.ReadOptions{}) + } + if spliceN == 0 && err == io.EOF { + // We reached the end of the file. Eat the error and exit the loop. + err = nil + break + } + n += spliceN + if err == syserror.ErrWouldBlock && !nonBlock { + err = dw.waitForBoth(t) + } + if err != nil { + break + } + } + } else { + // Read inFile to buffer, then write the contents to outFile. + buf := make([]byte, count) + for n < count { + var readN int64 + if offset != -1 { + readN, err = inFile.PRead(t, usermem.BytesIOSequence(buf), offset, vfs.ReadOptions{}) + offset += readN + } else { + readN, err = inFile.Read(t, usermem.BytesIOSequence(buf), vfs.ReadOptions{}) + } + if readN == 0 && err == io.EOF { + // We reached the end of the file. Eat the error and exit the loop. + err = nil + break + } + n += readN + if err != nil { + break + } + + // Write all of the bytes that we read. This may need + // multiple write calls to complete. + wbuf := buf[:n] + for len(wbuf) > 0 { + var writeN int64 + writeN, err = outFile.Write(t, usermem.BytesIOSequence(wbuf), vfs.WriteOptions{}) + wbuf = wbuf[writeN:] + if err == syserror.ErrWouldBlock && !nonBlock { + err = dw.waitForOut(t) + } + if err != nil { + // We didn't complete the write. Only + // report the bytes that were actually + // written, and rewind the offset. + notWritten := int64(len(wbuf)) + n -= notWritten + if offset != -1 { + offset -= notWritten + } + break + } + } + if err == syserror.ErrWouldBlock && !nonBlock { + err = dw.waitForBoth(t) + } + if err != nil { + break + } + } + } + + if offsetAddr != 0 { + // Copy out the new offset. + if _, err := t.CopyOut(offsetAddr, offset); err != nil { + return 0, nil, err + } + } + + if n == 0 { + return 0, nil, err + } + + inFile.Dentry().InotifyWithParent(t, linux.IN_ACCESS, 0, vfs.PathEvent) + outFile.Dentry().InotifyWithParent(t, linux.IN_MODIFY, 0, vfs.PathEvent) + return uintptr(n), nil, nil +} + +// dualWaiter is used to wait on one or both vfs.FileDescriptions. It is not +// thread-safe, and does not take a reference on the vfs.FileDescriptions. +// +// Users must call destroy() when finished. +type dualWaiter struct { + inFile *vfs.FileDescription + outFile *vfs.FileDescription + + inW waiter.Entry + inCh chan struct{} + outW waiter.Entry + outCh chan struct{} +} + +// waitForBoth waits for both dw.inFile and dw.outFile to be ready. +func (dw *dualWaiter) waitForBoth(t *kernel.Task) error { + if dw.inFile.Readiness(eventMaskRead)&eventMaskRead == 0 { + if dw.inCh == nil { + dw.inW, dw.inCh = waiter.NewChannelEntry(nil) + dw.inFile.EventRegister(&dw.inW, eventMaskRead) + // We might be ready now. Try again before blocking. + return nil + } + if err := t.Block(dw.inCh); err != nil { + return err + } + } + return dw.waitForOut(t) +} + +// waitForOut waits for dw.outfile to be read. +func (dw *dualWaiter) waitForOut(t *kernel.Task) error { + if dw.outFile.Readiness(eventMaskWrite)&eventMaskWrite == 0 { + if dw.outCh == nil { + dw.outW, dw.outCh = waiter.NewChannelEntry(nil) + dw.outFile.EventRegister(&dw.outW, eventMaskWrite) + // We might be ready now. Try again before blocking. + return nil + } + if err := t.Block(dw.outCh); err != nil { + return err + } + } + return nil +} + +// destroy cleans up resources help by dw. No more calls to wait* can occur +// after destroy is called. +func (dw *dualWaiter) destroy() { + if dw.inCh != nil { + dw.inFile.EventUnregister(&dw.inW) + dw.inCh = nil + } + if dw.outCh != nil { + dw.outFile.EventUnregister(&dw.outW) + dw.outCh = nil + } + dw.inFile = nil + dw.outFile = nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/stat.go b/pkg/sentry/syscalls/linux/vfs2/stat.go new file mode 100644 index 000000000..0f5d5189c --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/stat.go @@ -0,0 +1,388 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/bits" + "gvisor.dev/gvisor/pkg/fspath" + "gvisor.dev/gvisor/pkg/gohacks" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Stat implements Linux syscall stat(2). +func Stat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + statAddr := args[1].Pointer() + return 0, nil, fstatat(t, linux.AT_FDCWD, pathAddr, statAddr, 0 /* flags */) +} + +// Lstat implements Linux syscall lstat(2). +func Lstat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + statAddr := args[1].Pointer() + return 0, nil, fstatat(t, linux.AT_FDCWD, pathAddr, statAddr, linux.AT_SYMLINK_NOFOLLOW) +} + +// Newfstatat implements Linux syscall newfstatat, which backs fstatat(2). +func Newfstatat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + statAddr := args[2].Pointer() + flags := args[3].Int() + return 0, nil, fstatat(t, dirfd, pathAddr, statAddr, flags) +} + +func fstatat(t *kernel.Task, dirfd int32, pathAddr, statAddr usermem.Addr, flags int32) error { + if flags&^(linux.AT_EMPTY_PATH|linux.AT_SYMLINK_NOFOLLOW) != 0 { + return syserror.EINVAL + } + + opts := vfs.StatOptions{ + Mask: linux.STATX_BASIC_STATS, + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + + root := t.FSContext().RootDirectoryVFS2() + defer root.DecRef(t) + start := root + if !path.Absolute { + if !path.HasComponents() && flags&linux.AT_EMPTY_PATH == 0 { + return syserror.ENOENT + } + if dirfd == linux.AT_FDCWD { + start = t.FSContext().WorkingDirectoryVFS2() + defer start.DecRef(t) + } else { + dirfile := t.GetFileVFS2(dirfd) + if dirfile == nil { + return syserror.EBADF + } + if !path.HasComponents() { + // Use FileDescription.Stat() instead of + // VirtualFilesystem.StatAt() for fstatat(fd, ""), since the + // former may be able to use opened file state to expedite the + // Stat. + statx, err := dirfile.Stat(t, opts) + dirfile.DecRef(t) + if err != nil { + return err + } + var stat linux.Stat + convertStatxToUserStat(t, &statx, &stat) + _, err = stat.CopyOut(t, statAddr) + return err + } + start = dirfile.VirtualDentry() + start.IncRef() + defer start.DecRef(t) + dirfile.DecRef(t) + } + } + + statx, err := t.Kernel().VFS().StatAt(t, t.Credentials(), &vfs.PathOperation{ + Root: root, + Start: start, + Path: path, + FollowFinalSymlink: flags&linux.AT_SYMLINK_NOFOLLOW == 0, + }, &opts) + if err != nil { + return err + } + var stat linux.Stat + convertStatxToUserStat(t, &statx, &stat) + _, err = stat.CopyOut(t, statAddr) + return err +} + +func timespecFromStatxTimestamp(sxts linux.StatxTimestamp) linux.Timespec { + return linux.Timespec{ + Sec: sxts.Sec, + Nsec: int64(sxts.Nsec), + } +} + +// Fstat implements Linux syscall fstat(2). +func Fstat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + statAddr := args[1].Pointer() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + statx, err := file.Stat(t, vfs.StatOptions{ + Mask: linux.STATX_BASIC_STATS, + }) + if err != nil { + return 0, nil, err + } + var stat linux.Stat + convertStatxToUserStat(t, &statx, &stat) + _, err = stat.CopyOut(t, statAddr) + return 0, nil, err +} + +// Statx implements Linux syscall statx(2). +func Statx(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + flags := args[2].Int() + mask := args[3].Uint() + statxAddr := args[4].Pointer() + + if flags&^(linux.AT_EMPTY_PATH|linux.AT_SYMLINK_NOFOLLOW|linux.AT_STATX_SYNC_TYPE) != 0 { + return 0, nil, syserror.EINVAL + } + // Make sure that only one sync type option is set. + syncType := uint32(flags & linux.AT_STATX_SYNC_TYPE) + if syncType != 0 && !bits.IsPowerOfTwo32(syncType) { + return 0, nil, syserror.EINVAL + } + if mask&linux.STATX__RESERVED != 0 { + return 0, nil, syserror.EINVAL + } + + opts := vfs.StatOptions{ + Mask: mask, + Sync: uint32(flags & linux.AT_STATX_SYNC_TYPE), + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + + root := t.FSContext().RootDirectoryVFS2() + defer root.DecRef(t) + start := root + if !path.Absolute { + if !path.HasComponents() && flags&linux.AT_EMPTY_PATH == 0 { + return 0, nil, syserror.ENOENT + } + if dirfd == linux.AT_FDCWD { + start = t.FSContext().WorkingDirectoryVFS2() + defer start.DecRef(t) + } else { + dirfile := t.GetFileVFS2(dirfd) + if dirfile == nil { + return 0, nil, syserror.EBADF + } + if !path.HasComponents() { + // Use FileDescription.Stat() instead of + // VirtualFilesystem.StatAt() for statx(fd, ""), since the + // former may be able to use opened file state to expedite the + // Stat. + statx, err := dirfile.Stat(t, opts) + dirfile.DecRef(t) + if err != nil { + return 0, nil, err + } + userifyStatx(t, &statx) + _, err = statx.CopyOut(t, statxAddr) + return 0, nil, err + } + start = dirfile.VirtualDentry() + start.IncRef() + defer start.DecRef(t) + dirfile.DecRef(t) + } + } + + statx, err := t.Kernel().VFS().StatAt(t, t.Credentials(), &vfs.PathOperation{ + Root: root, + Start: start, + Path: path, + FollowFinalSymlink: flags&linux.AT_SYMLINK_NOFOLLOW == 0, + }, &opts) + if err != nil { + return 0, nil, err + } + userifyStatx(t, &statx) + _, err = statx.CopyOut(t, statxAddr) + return 0, nil, err +} + +func userifyStatx(t *kernel.Task, statx *linux.Statx) { + userns := t.UserNamespace() + statx.UID = uint32(auth.KUID(statx.UID).In(userns).OrOverflow()) + statx.GID = uint32(auth.KGID(statx.GID).In(userns).OrOverflow()) +} + +// Readlink implements Linux syscall readlink(2). +func Readlink(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + bufAddr := args[1].Pointer() + size := args[2].SizeT() + return readlinkat(t, linux.AT_FDCWD, pathAddr, bufAddr, size) +} + +// Access implements Linux syscall access(2). +func Access(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + addr := args[0].Pointer() + mode := args[1].ModeT() + + return 0, nil, accessAt(t, linux.AT_FDCWD, addr, mode) +} + +// Faccessat implements Linux syscall faccessat(2). +// +// Note that the faccessat() system call does not take a flags argument: +// "The raw faccessat() system call takes only the first three arguments. The +// AT_EACCESS and AT_SYMLINK_NOFOLLOW flags are actually implemented within +// the glibc wrapper function for faccessat(). If either of these flags is +// specified, then the wrapper function employs fstatat(2) to determine access +// permissions." - faccessat(2) +func Faccessat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + addr := args[1].Pointer() + mode := args[2].ModeT() + + return 0, nil, accessAt(t, dirfd, addr, mode) +} + +func accessAt(t *kernel.Task, dirfd int32, pathAddr usermem.Addr, mode uint) error { + const rOK = 4 + const wOK = 2 + const xOK = 1 + + // Sanity check the mode. + if mode&^(rOK|wOK|xOK) != 0 { + return syserror.EINVAL + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, dirfd, path, disallowEmptyPath, followFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + + // access(2) and faccessat(2) check permissions using real + // UID/GID, not effective UID/GID. + // + // "access() needs to use the real uid/gid, not the effective + // uid/gid. We do this by temporarily clearing all FS-related + // capabilities and switching the fsuid/fsgid around to the + // real ones." -fs/open.c:faccessat + creds := t.Credentials().Fork() + creds.EffectiveKUID = creds.RealKUID + creds.EffectiveKGID = creds.RealKGID + if creds.EffectiveKUID.In(creds.UserNamespace) == auth.RootUID { + creds.EffectiveCaps = creds.PermittedCaps + } else { + creds.EffectiveCaps = 0 + } + + return t.Kernel().VFS().AccessAt(t, creds, vfs.AccessTypes(mode), &tpop.pop) +} + +// Readlinkat implements Linux syscall mknodat(2). +func Readlinkat(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + dirfd := args[0].Int() + pathAddr := args[1].Pointer() + bufAddr := args[2].Pointer() + size := args[3].SizeT() + return readlinkat(t, dirfd, pathAddr, bufAddr, size) +} + +func readlinkat(t *kernel.Task, dirfd int32, pathAddr, bufAddr usermem.Addr, size uint) (uintptr, *kernel.SyscallControl, error) { + if int(size) <= 0 { + return 0, nil, syserror.EINVAL + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + // "Since Linux 2.6.39, pathname can be an empty string, in which case the + // call operates on the symbolic link referred to by dirfd ..." - + // readlinkat(2) + tpop, err := getTaskPathOperation(t, dirfd, path, allowEmptyPath, nofollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + target, err := t.Kernel().VFS().ReadlinkAt(t, t.Credentials(), &tpop.pop) + if err != nil { + return 0, nil, err + } + + if len(target) > int(size) { + target = target[:size] + } + n, err := t.CopyOutBytes(bufAddr, gohacks.ImmutableBytesFromString(target)) + if n == 0 { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +// Statfs implements Linux syscall statfs(2). +func Statfs(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + bufAddr := args[1].Pointer() + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, followFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + statfs, err := t.Kernel().VFS().StatFSAt(t, t.Credentials(), &tpop.pop) + if err != nil { + return 0, nil, err + } + _, err = statfs.CopyOut(t, bufAddr) + return 0, nil, err +} + +// Fstatfs implements Linux syscall fstatfs(2). +func Fstatfs(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + bufAddr := args[1].Pointer() + + tpop, err := getTaskPathOperation(t, fd, fspath.Path{}, allowEmptyPath, nofollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + statfs, err := t.Kernel().VFS().StatFSAt(t, t.Credentials(), &tpop.pop) + if err != nil { + return 0, nil, err + } + _, err = statfs.CopyOut(t, bufAddr) + return 0, nil, err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/stat_amd64.go b/pkg/sentry/syscalls/linux/vfs2/stat_amd64.go new file mode 100644 index 000000000..2da538fc6 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/stat_amd64.go @@ -0,0 +1,46 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build amd64 + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" +) + +// This takes both input and output as pointer arguments to avoid copying large +// structs. +func convertStatxToUserStat(t *kernel.Task, statx *linux.Statx, stat *linux.Stat) { + // Linux just copies fields from struct kstat without regard to struct + // kstat::result_mask (fs/stat.c:cp_new_stat()), so we do too. + userns := t.UserNamespace() + *stat = linux.Stat{ + Dev: uint64(linux.MakeDeviceID(uint16(statx.DevMajor), statx.DevMinor)), + Ino: statx.Ino, + Nlink: uint64(statx.Nlink), + Mode: uint32(statx.Mode), + UID: uint32(auth.KUID(statx.UID).In(userns).OrOverflow()), + GID: uint32(auth.KGID(statx.GID).In(userns).OrOverflow()), + Rdev: uint64(linux.MakeDeviceID(uint16(statx.RdevMajor), statx.RdevMinor)), + Size: int64(statx.Size), + Blksize: int64(statx.Blksize), + Blocks: int64(statx.Blocks), + ATime: timespecFromStatxTimestamp(statx.Atime), + MTime: timespecFromStatxTimestamp(statx.Mtime), + CTime: timespecFromStatxTimestamp(statx.Ctime), + } +} diff --git a/pkg/sentry/syscalls/linux/vfs2/stat_arm64.go b/pkg/sentry/syscalls/linux/vfs2/stat_arm64.go new file mode 100644 index 000000000..88b9c7627 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/stat_arm64.go @@ -0,0 +1,46 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build arm64 + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/kernel/auth" +) + +// This takes both input and output as pointer arguments to avoid copying large +// structs. +func convertStatxToUserStat(t *kernel.Task, statx *linux.Statx, stat *linux.Stat) { + // Linux just copies fields from struct kstat without regard to struct + // kstat::result_mask (fs/stat.c:cp_new_stat()), so we do too. + userns := t.UserNamespace() + *stat = linux.Stat{ + Dev: uint64(linux.MakeDeviceID(uint16(statx.DevMajor), statx.DevMinor)), + Ino: statx.Ino, + Nlink: uint32(statx.Nlink), + Mode: uint32(statx.Mode), + UID: uint32(auth.KUID(statx.UID).In(userns).OrOverflow()), + GID: uint32(auth.KGID(statx.GID).In(userns).OrOverflow()), + Rdev: uint64(linux.MakeDeviceID(uint16(statx.RdevMajor), statx.RdevMinor)), + Size: int64(statx.Size), + Blksize: int32(statx.Blksize), + Blocks: int64(statx.Blocks), + ATime: timespecFromStatxTimestamp(statx.Atime), + MTime: timespecFromStatxTimestamp(statx.Mtime), + CTime: timespecFromStatxTimestamp(statx.Ctime), + } +} diff --git a/pkg/sentry/syscalls/linux/vfs2/sync.go b/pkg/sentry/syscalls/linux/vfs2/sync.go new file mode 100644 index 000000000..a6491ac37 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/sync.go @@ -0,0 +1,115 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/syserror" +) + +// Sync implements Linux syscall sync(2). +func Sync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, t.Kernel().VFS().SyncAllFilesystems(t) +} + +// Syncfs implements Linux syscall syncfs(2). +func Syncfs(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + return 0, nil, file.SyncFS(t) +} + +// Fsync implements Linux syscall fsync(2). +func Fsync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + return 0, nil, file.Sync(t) +} + +// Fdatasync implements Linux syscall fdatasync(2). +func Fdatasync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + // TODO(gvisor.dev/issue/1897): Avoid writeback of unnecessary metadata. + return Fsync(t, args) +} + +// SyncFileRange implements Linux syscall sync_file_range(2). +func SyncFileRange(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + offset := args[1].Int64() + nbytes := args[2].Int64() + flags := args[3].Uint() + + // Check for negative values and overflow. + if offset < 0 || offset+nbytes < 0 { + return 0, nil, syserror.EINVAL + } + if flags&^(linux.SYNC_FILE_RANGE_WAIT_BEFORE|linux.SYNC_FILE_RANGE_WRITE|linux.SYNC_FILE_RANGE_WAIT_AFTER) != 0 { + return 0, nil, syserror.EINVAL + } + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + // TODO(gvisor.dev/issue/1897): Currently, the only file syncing we support + // is a full-file sync, i.e. fsync(2). As a result, there are severe + // limitations on how much we support sync_file_range: + // - In Linux, sync_file_range(2) doesn't write out the file's metadata, even + // if the file size is changed. We do. + // - We always sync the entire file instead of [offset, offset+nbytes). + // - We do not support the use of WAIT_BEFORE without WAIT_AFTER. For + // correctness, we would have to perform a write-out every time WAIT_BEFORE + // was used, but this would be much more expensive than expected if there + // were no write-out operations in progress. + // - Whenever WAIT_AFTER is used, we sync the file. + // - Ignore WRITE. If this flag is used with WAIT_AFTER, then the file will + // be synced anyway. If this flag is used without WAIT_AFTER, then it is + // safe (and less expensive) to do nothing, because the syscall will not + // wait for the write-out to complete--we only need to make sure that the + // next time WAIT_BEFORE or WAIT_AFTER are used, the write-out completes. + // - According to fs/sync.c, WAIT_BEFORE|WAIT_AFTER "will detect any I/O + // errors or ENOSPC conditions and will return those to the caller, after + // clearing the EIO and ENOSPC flags in the address_space." We don't do + // this. + + if flags&linux.SYNC_FILE_RANGE_WAIT_BEFORE != 0 && + flags&linux.SYNC_FILE_RANGE_WAIT_AFTER == 0 { + t.Kernel().EmitUnimplementedEvent(t) + return 0, nil, syserror.ENOSYS + } + + if flags&linux.SYNC_FILE_RANGE_WAIT_AFTER != 0 { + if err := file.Sync(t); err != nil { + return 0, nil, syserror.ConvertIntr(err, kernel.ERESTARTSYS) + } + } + return 0, nil, nil +} diff --git a/pkg/sentry/syscalls/linux/vfs2/timerfd.go b/pkg/sentry/syscalls/linux/vfs2/timerfd.go new file mode 100644 index 000000000..7a26890ef --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/timerfd.go @@ -0,0 +1,127 @@ +// Copyright 2018 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/fsimpl/timerfd" + "gvisor.dev/gvisor/pkg/sentry/kernel" + ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" + "gvisor.dev/gvisor/pkg/syserror" +) + +// TimerfdCreate implements Linux syscall timerfd_create(2). +func TimerfdCreate(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + clockID := args[0].Int() + flags := args[1].Int() + + if flags&^(linux.TFD_CLOEXEC|linux.TFD_NONBLOCK) != 0 { + return 0, nil, syserror.EINVAL + } + + // Timerfds aren't writable per se (their implementation of Write just + // returns EINVAL), but they are "opened for writing", which is necessary + // to actually reach said implementation of Write. + fileFlags := uint32(linux.O_RDWR) + if flags&linux.TFD_NONBLOCK != 0 { + fileFlags |= linux.O_NONBLOCK + } + + var clock ktime.Clock + switch clockID { + case linux.CLOCK_REALTIME: + clock = t.Kernel().RealtimeClock() + case linux.CLOCK_MONOTONIC, linux.CLOCK_BOOTTIME: + clock = t.Kernel().MonotonicClock() + default: + return 0, nil, syserror.EINVAL + } + vfsObj := t.Kernel().VFS() + file, err := timerfd.New(t, vfsObj, clock, fileFlags) + if err != nil { + return 0, nil, err + } + defer file.DecRef(t) + fd, err := t.NewFDFromVFS2(0, file, kernel.FDFlags{ + CloseOnExec: flags&linux.TFD_CLOEXEC != 0, + }) + if err != nil { + return 0, nil, err + } + return uintptr(fd), nil, nil +} + +// TimerfdSettime implements Linux syscall timerfd_settime(2). +func TimerfdSettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + flags := args[1].Int() + newValAddr := args[2].Pointer() + oldValAddr := args[3].Pointer() + + if flags&^(linux.TFD_TIMER_ABSTIME) != 0 { + return 0, nil, syserror.EINVAL + } + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + tfd, ok := file.Impl().(*timerfd.TimerFileDescription) + if !ok { + return 0, nil, syserror.EINVAL + } + + var newVal linux.Itimerspec + if _, err := t.CopyIn(newValAddr, &newVal); err != nil { + return 0, nil, err + } + newS, err := ktime.SettingFromItimerspec(newVal, flags&linux.TFD_TIMER_ABSTIME != 0, tfd.Clock()) + if err != nil { + return 0, nil, err + } + tm, oldS := tfd.SetTime(newS) + if oldValAddr != 0 { + oldVal := ktime.ItimerspecFromSetting(tm, oldS) + if _, err := t.CopyOut(oldValAddr, &oldVal); err != nil { + return 0, nil, err + } + } + return 0, nil, nil +} + +// TimerfdGettime implements Linux syscall timerfd_gettime(2). +func TimerfdGettime(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + curValAddr := args[1].Pointer() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + tfd, ok := file.Impl().(*timerfd.TimerFileDescription) + if !ok { + return 0, nil, syserror.EINVAL + } + + tm, s := tfd.GetTime() + curVal := ktime.ItimerspecFromSetting(tm, s) + _, err := t.CopyOut(curValAddr, &curVal) + return 0, nil, err +} diff --git a/pkg/sentry/syscalls/linux/vfs2/vfs2.go b/pkg/sentry/syscalls/linux/vfs2/vfs2.go new file mode 100644 index 000000000..c576d9475 --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/vfs2.go @@ -0,0 +1,268 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// Package vfs2 provides syscall implementations that use VFS2. +package vfs2 + +import ( + "gvisor.dev/gvisor/pkg/sentry/syscalls" + "gvisor.dev/gvisor/pkg/sentry/syscalls/linux" +) + +// Override syscall table to add syscalls implementations from this package. +func Override() { + // Override AMD64. + s := linux.AMD64 + s.Table[0] = syscalls.Supported("read", Read) + s.Table[1] = syscalls.Supported("write", Write) + s.Table[2] = syscalls.Supported("open", Open) + s.Table[3] = syscalls.Supported("close", Close) + s.Table[4] = syscalls.Supported("stat", Stat) + s.Table[5] = syscalls.Supported("fstat", Fstat) + s.Table[6] = syscalls.Supported("lstat", Lstat) + s.Table[7] = syscalls.Supported("poll", Poll) + s.Table[8] = syscalls.Supported("lseek", Lseek) + s.Table[9] = syscalls.Supported("mmap", Mmap) + s.Table[16] = syscalls.Supported("ioctl", Ioctl) + s.Table[17] = syscalls.Supported("pread64", Pread64) + s.Table[18] = syscalls.Supported("pwrite64", Pwrite64) + s.Table[19] = syscalls.Supported("readv", Readv) + s.Table[20] = syscalls.Supported("writev", Writev) + s.Table[21] = syscalls.Supported("access", Access) + s.Table[22] = syscalls.Supported("pipe", Pipe) + s.Table[23] = syscalls.Supported("select", Select) + s.Table[32] = syscalls.Supported("dup", Dup) + s.Table[33] = syscalls.Supported("dup2", Dup2) + s.Table[40] = syscalls.Supported("sendfile", Sendfile) + s.Table[41] = syscalls.Supported("socket", Socket) + s.Table[42] = syscalls.Supported("connect", Connect) + s.Table[43] = syscalls.Supported("accept", Accept) + s.Table[44] = syscalls.Supported("sendto", SendTo) + s.Table[45] = syscalls.Supported("recvfrom", RecvFrom) + s.Table[46] = syscalls.Supported("sendmsg", SendMsg) + s.Table[47] = syscalls.Supported("recvmsg", RecvMsg) + s.Table[48] = syscalls.Supported("shutdown", Shutdown) + s.Table[49] = syscalls.Supported("bind", Bind) + s.Table[50] = syscalls.Supported("listen", Listen) + s.Table[51] = syscalls.Supported("getsockname", GetSockName) + s.Table[52] = syscalls.Supported("getpeername", GetPeerName) + s.Table[53] = syscalls.Supported("socketpair", SocketPair) + s.Table[54] = syscalls.Supported("setsockopt", SetSockOpt) + s.Table[55] = syscalls.Supported("getsockopt", GetSockOpt) + s.Table[59] = syscalls.Supported("execve", Execve) + s.Table[72] = syscalls.Supported("fcntl", Fcntl) + s.Table[73] = syscalls.Supported("flock", Flock) + s.Table[74] = syscalls.Supported("fsync", Fsync) + s.Table[75] = syscalls.Supported("fdatasync", Fdatasync) + s.Table[76] = syscalls.Supported("truncate", Truncate) + s.Table[77] = syscalls.Supported("ftruncate", Ftruncate) + s.Table[78] = syscalls.Supported("getdents", Getdents) + s.Table[79] = syscalls.Supported("getcwd", Getcwd) + s.Table[80] = syscalls.Supported("chdir", Chdir) + s.Table[81] = syscalls.Supported("fchdir", Fchdir) + s.Table[82] = syscalls.Supported("rename", Rename) + s.Table[83] = syscalls.Supported("mkdir", Mkdir) + s.Table[84] = syscalls.Supported("rmdir", Rmdir) + s.Table[85] = syscalls.Supported("creat", Creat) + s.Table[86] = syscalls.Supported("link", Link) + s.Table[87] = syscalls.Supported("unlink", Unlink) + s.Table[88] = syscalls.Supported("symlink", Symlink) + s.Table[89] = syscalls.Supported("readlink", Readlink) + s.Table[90] = syscalls.Supported("chmod", Chmod) + s.Table[91] = syscalls.Supported("fchmod", Fchmod) + s.Table[92] = syscalls.Supported("chown", Chown) + s.Table[93] = syscalls.Supported("fchown", Fchown) + s.Table[94] = syscalls.Supported("lchown", Lchown) + s.Table[132] = syscalls.Supported("utime", Utime) + s.Table[133] = syscalls.Supported("mknod", Mknod) + s.Table[137] = syscalls.Supported("statfs", Statfs) + s.Table[138] = syscalls.Supported("fstatfs", Fstatfs) + s.Table[161] = syscalls.Supported("chroot", Chroot) + s.Table[162] = syscalls.Supported("sync", Sync) + s.Table[165] = syscalls.Supported("mount", Mount) + s.Table[166] = syscalls.Supported("umount2", Umount2) + s.Table[187] = syscalls.Supported("readahead", Readahead) + s.Table[188] = syscalls.Supported("setxattr", Setxattr) + s.Table[189] = syscalls.Supported("lsetxattr", Lsetxattr) + s.Table[190] = syscalls.Supported("fsetxattr", Fsetxattr) + s.Table[191] = syscalls.Supported("getxattr", Getxattr) + s.Table[192] = syscalls.Supported("lgetxattr", Lgetxattr) + s.Table[193] = syscalls.Supported("fgetxattr", Fgetxattr) + s.Table[194] = syscalls.Supported("listxattr", Listxattr) + s.Table[195] = syscalls.Supported("llistxattr", Llistxattr) + s.Table[196] = syscalls.Supported("flistxattr", Flistxattr) + s.Table[197] = syscalls.Supported("removexattr", Removexattr) + s.Table[198] = syscalls.Supported("lremovexattr", Lremovexattr) + s.Table[199] = syscalls.Supported("fremovexattr", Fremovexattr) + s.Table[209] = syscalls.PartiallySupported("io_submit", IoSubmit, "Generally supported with exceptions. User ring optimizations are not implemented.", []string{"gvisor.dev/issue/204"}) + s.Table[213] = syscalls.Supported("epoll_create", EpollCreate) + s.Table[217] = syscalls.Supported("getdents64", Getdents64) + s.Table[221] = syscalls.PartiallySupported("fadvise64", Fadvise64, "The syscall is 'supported', but ignores all provided advice.", nil) + s.Table[232] = syscalls.Supported("epoll_wait", EpollWait) + s.Table[233] = syscalls.Supported("epoll_ctl", EpollCtl) + s.Table[235] = syscalls.Supported("utimes", Utimes) + s.Table[253] = syscalls.PartiallySupported("inotify_init", InotifyInit, "inotify events are only available inside the sandbox.", nil) + s.Table[254] = syscalls.PartiallySupported("inotify_add_watch", InotifyAddWatch, "inotify events are only available inside the sandbox.", nil) + s.Table[255] = syscalls.PartiallySupported("inotify_rm_watch", InotifyRmWatch, "inotify events are only available inside the sandbox.", nil) + s.Table[257] = syscalls.Supported("openat", Openat) + s.Table[258] = syscalls.Supported("mkdirat", Mkdirat) + s.Table[259] = syscalls.Supported("mknodat", Mknodat) + s.Table[260] = syscalls.Supported("fchownat", Fchownat) + s.Table[261] = syscalls.Supported("futimesat", Futimesat) + s.Table[262] = syscalls.Supported("newfstatat", Newfstatat) + s.Table[263] = syscalls.Supported("unlinkat", Unlinkat) + s.Table[264] = syscalls.Supported("renameat", Renameat) + s.Table[265] = syscalls.Supported("linkat", Linkat) + s.Table[266] = syscalls.Supported("symlinkat", Symlinkat) + s.Table[267] = syscalls.Supported("readlinkat", Readlinkat) + s.Table[268] = syscalls.Supported("fchmodat", Fchmodat) + s.Table[269] = syscalls.Supported("faccessat", Faccessat) + s.Table[270] = syscalls.Supported("pselect", Pselect) + s.Table[271] = syscalls.Supported("ppoll", Ppoll) + s.Table[275] = syscalls.Supported("splice", Splice) + s.Table[276] = syscalls.Supported("tee", Tee) + s.Table[277] = syscalls.Supported("sync_file_range", SyncFileRange) + s.Table[280] = syscalls.Supported("utimensat", Utimensat) + s.Table[281] = syscalls.Supported("epoll_pwait", EpollPwait) + s.Table[282] = syscalls.Supported("signalfd", Signalfd) + s.Table[283] = syscalls.Supported("timerfd_create", TimerfdCreate) + s.Table[284] = syscalls.Supported("eventfd", Eventfd) + s.Table[285] = syscalls.PartiallySupported("fallocate", Fallocate, "Not all options are supported.", nil) + s.Table[286] = syscalls.Supported("timerfd_settime", TimerfdSettime) + s.Table[287] = syscalls.Supported("timerfd_gettime", TimerfdGettime) + s.Table[288] = syscalls.Supported("accept4", Accept4) + s.Table[289] = syscalls.Supported("signalfd4", Signalfd4) + s.Table[290] = syscalls.Supported("eventfd2", Eventfd2) + s.Table[291] = syscalls.Supported("epoll_create1", EpollCreate1) + s.Table[292] = syscalls.Supported("dup3", Dup3) + s.Table[293] = syscalls.Supported("pipe2", Pipe2) + s.Table[294] = syscalls.PartiallySupported("inotify_init1", InotifyInit1, "inotify events are only available inside the sandbox.", nil) + s.Table[295] = syscalls.Supported("preadv", Preadv) + s.Table[296] = syscalls.Supported("pwritev", Pwritev) + s.Table[299] = syscalls.Supported("recvmmsg", RecvMMsg) + s.Table[306] = syscalls.Supported("syncfs", Syncfs) + s.Table[307] = syscalls.Supported("sendmmsg", SendMMsg) + s.Table[316] = syscalls.Supported("renameat2", Renameat2) + s.Table[319] = syscalls.Supported("memfd_create", MemfdCreate) + s.Table[322] = syscalls.Supported("execveat", Execveat) + s.Table[327] = syscalls.Supported("preadv2", Preadv2) + s.Table[328] = syscalls.Supported("pwritev2", Pwritev2) + s.Table[332] = syscalls.Supported("statx", Statx) + s.Init() + + // Override ARM64. + s = linux.ARM64 + s.Table[5] = syscalls.Supported("setxattr", Setxattr) + s.Table[6] = syscalls.Supported("lsetxattr", Lsetxattr) + s.Table[7] = syscalls.Supported("fsetxattr", Fsetxattr) + s.Table[8] = syscalls.Supported("getxattr", Getxattr) + s.Table[9] = syscalls.Supported("lgetxattr", Lgetxattr) + s.Table[10] = syscalls.Supported("fgetxattr", Fgetxattr) + s.Table[11] = syscalls.Supported("listxattr", Listxattr) + s.Table[12] = syscalls.Supported("llistxattr", Llistxattr) + s.Table[13] = syscalls.Supported("flistxattr", Flistxattr) + s.Table[14] = syscalls.Supported("removexattr", Removexattr) + s.Table[15] = syscalls.Supported("lremovexattr", Lremovexattr) + s.Table[16] = syscalls.Supported("fremovexattr", Fremovexattr) + s.Table[17] = syscalls.Supported("getcwd", Getcwd) + s.Table[19] = syscalls.Supported("eventfd2", Eventfd2) + s.Table[20] = syscalls.Supported("epoll_create1", EpollCreate1) + s.Table[21] = syscalls.Supported("epoll_ctl", EpollCtl) + s.Table[22] = syscalls.Supported("epoll_pwait", EpollPwait) + s.Table[23] = syscalls.Supported("dup", Dup) + s.Table[24] = syscalls.Supported("dup3", Dup3) + s.Table[25] = syscalls.Supported("fcntl", Fcntl) + s.Table[26] = syscalls.PartiallySupported("inotify_init1", InotifyInit1, "inotify events are only available inside the sandbox.", nil) + s.Table[27] = syscalls.PartiallySupported("inotify_add_watch", InotifyAddWatch, "inotify events are only available inside the sandbox.", nil) + s.Table[28] = syscalls.PartiallySupported("inotify_rm_watch", InotifyRmWatch, "inotify events are only available inside the sandbox.", nil) + s.Table[29] = syscalls.Supported("ioctl", Ioctl) + s.Table[32] = syscalls.Supported("flock", Flock) + s.Table[33] = syscalls.Supported("mknodat", Mknodat) + s.Table[34] = syscalls.Supported("mkdirat", Mkdirat) + s.Table[35] = syscalls.Supported("unlinkat", Unlinkat) + s.Table[36] = syscalls.Supported("symlinkat", Symlinkat) + s.Table[37] = syscalls.Supported("linkat", Linkat) + s.Table[38] = syscalls.Supported("renameat", Renameat) + s.Table[39] = syscalls.Supported("umount2", Umount2) + s.Table[40] = syscalls.Supported("mount", Mount) + s.Table[43] = syscalls.Supported("statfs", Statfs) + s.Table[44] = syscalls.Supported("fstatfs", Fstatfs) + s.Table[45] = syscalls.Supported("truncate", Truncate) + s.Table[46] = syscalls.Supported("ftruncate", Ftruncate) + s.Table[48] = syscalls.Supported("faccessat", Faccessat) + s.Table[49] = syscalls.Supported("chdir", Chdir) + s.Table[50] = syscalls.Supported("fchdir", Fchdir) + s.Table[51] = syscalls.Supported("chroot", Chroot) + s.Table[52] = syscalls.Supported("fchmod", Fchmod) + s.Table[53] = syscalls.Supported("fchmodat", Fchmodat) + s.Table[54] = syscalls.Supported("fchownat", Fchownat) + s.Table[55] = syscalls.Supported("fchown", Fchown) + s.Table[56] = syscalls.Supported("openat", Openat) + s.Table[57] = syscalls.Supported("close", Close) + s.Table[59] = syscalls.Supported("pipe2", Pipe2) + s.Table[61] = syscalls.Supported("getdents64", Getdents64) + s.Table[62] = syscalls.Supported("lseek", Lseek) + s.Table[63] = syscalls.Supported("read", Read) + s.Table[64] = syscalls.Supported("write", Write) + s.Table[65] = syscalls.Supported("readv", Readv) + s.Table[66] = syscalls.Supported("writev", Writev) + s.Table[67] = syscalls.Supported("pread64", Pread64) + s.Table[68] = syscalls.Supported("pwrite64", Pwrite64) + s.Table[69] = syscalls.Supported("preadv", Preadv) + s.Table[70] = syscalls.Supported("pwritev", Pwritev) + s.Table[72] = syscalls.Supported("pselect", Pselect) + s.Table[73] = syscalls.Supported("ppoll", Ppoll) + s.Table[74] = syscalls.Supported("signalfd4", Signalfd4) + s.Table[76] = syscalls.Supported("splice", Splice) + s.Table[77] = syscalls.Supported("tee", Tee) + s.Table[78] = syscalls.Supported("readlinkat", Readlinkat) + s.Table[80] = syscalls.Supported("fstat", Fstat) + s.Table[81] = syscalls.Supported("sync", Sync) + s.Table[82] = syscalls.Supported("fsync", Fsync) + s.Table[83] = syscalls.Supported("fdatasync", Fdatasync) + s.Table[84] = syscalls.Supported("sync_file_range", SyncFileRange) + s.Table[85] = syscalls.Supported("timerfd_create", TimerfdCreate) + s.Table[86] = syscalls.Supported("timerfd_settime", TimerfdSettime) + s.Table[87] = syscalls.Supported("timerfd_gettime", TimerfdGettime) + s.Table[88] = syscalls.Supported("utimensat", Utimensat) + s.Table[198] = syscalls.Supported("socket", Socket) + s.Table[199] = syscalls.Supported("socketpair", SocketPair) + s.Table[200] = syscalls.Supported("bind", Bind) + s.Table[201] = syscalls.Supported("listen", Listen) + s.Table[202] = syscalls.Supported("accept", Accept) + s.Table[203] = syscalls.Supported("connect", Connect) + s.Table[204] = syscalls.Supported("getsockname", GetSockName) + s.Table[205] = syscalls.Supported("getpeername", GetPeerName) + s.Table[206] = syscalls.Supported("sendto", SendTo) + s.Table[207] = syscalls.Supported("recvfrom", RecvFrom) + s.Table[208] = syscalls.Supported("setsockopt", SetSockOpt) + s.Table[209] = syscalls.Supported("getsockopt", GetSockOpt) + s.Table[210] = syscalls.Supported("shutdown", Shutdown) + s.Table[211] = syscalls.Supported("sendmsg", SendMsg) + s.Table[212] = syscalls.Supported("recvmsg", RecvMsg) + s.Table[221] = syscalls.Supported("execve", Execve) + s.Table[222] = syscalls.Supported("mmap", Mmap) + s.Table[242] = syscalls.Supported("accept4", Accept4) + s.Table[243] = syscalls.Supported("recvmmsg", RecvMMsg) + s.Table[267] = syscalls.Supported("syncfs", Syncfs) + s.Table[269] = syscalls.Supported("sendmmsg", SendMMsg) + s.Table[276] = syscalls.Supported("renameat2", Renameat2) + s.Table[279] = syscalls.Supported("memfd_create", MemfdCreate) + s.Table[281] = syscalls.Supported("execveat", Execveat) + s.Table[286] = syscalls.Supported("preadv2", Preadv2) + s.Table[287] = syscalls.Supported("pwritev2", Pwritev2) + s.Table[291] = syscalls.Supported("statx", Statx) + + s.Init() +} diff --git a/pkg/sentry/syscalls/linux/vfs2/xattr.go b/pkg/sentry/syscalls/linux/vfs2/xattr.go new file mode 100644 index 000000000..ef99246ed --- /dev/null +++ b/pkg/sentry/syscalls/linux/vfs2/xattr.go @@ -0,0 +1,356 @@ +// Copyright 2020 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package vfs2 + +import ( + "bytes" + + "gvisor.dev/gvisor/pkg/abi/linux" + "gvisor.dev/gvisor/pkg/gohacks" + "gvisor.dev/gvisor/pkg/sentry/arch" + "gvisor.dev/gvisor/pkg/sentry/kernel" + "gvisor.dev/gvisor/pkg/sentry/vfs" + "gvisor.dev/gvisor/pkg/syserror" + "gvisor.dev/gvisor/pkg/usermem" +) + +// Listxattr implements Linux syscall listxattr(2). +func Listxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return listxattr(t, args, followFinalSymlink) +} + +// Llistxattr implements Linux syscall llistxattr(2). +func Llistxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return listxattr(t, args, nofollowFinalSymlink) +} + +func listxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSymlink shouldFollowFinalSymlink) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + listAddr := args[1].Pointer() + size := args[2].SizeT() + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, shouldFollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + names, err := t.Kernel().VFS().ListxattrAt(t, t.Credentials(), &tpop.pop, uint64(size)) + if err != nil { + return 0, nil, err + } + n, err := copyOutXattrNameList(t, listAddr, size, names) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +// Flistxattr implements Linux syscall flistxattr(2). +func Flistxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + listAddr := args[1].Pointer() + size := args[2].SizeT() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + names, err := file.Listxattr(t, uint64(size)) + if err != nil { + return 0, nil, err + } + n, err := copyOutXattrNameList(t, listAddr, size, names) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +// Getxattr implements Linux syscall getxattr(2). +func Getxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return getxattr(t, args, followFinalSymlink) +} + +// Lgetxattr implements Linux syscall lgetxattr(2). +func Lgetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return getxattr(t, args, nofollowFinalSymlink) +} + +func getxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSymlink shouldFollowFinalSymlink) (uintptr, *kernel.SyscallControl, error) { + pathAddr := args[0].Pointer() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := args[3].SizeT() + + path, err := copyInPath(t, pathAddr) + if err != nil { + return 0, nil, err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, shouldFollowFinalSymlink) + if err != nil { + return 0, nil, err + } + defer tpop.Release(t) + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return 0, nil, err + } + + value, err := t.Kernel().VFS().GetxattrAt(t, t.Credentials(), &tpop.pop, &vfs.GetxattrOptions{ + Name: name, + Size: uint64(size), + }) + if err != nil { + return 0, nil, err + } + n, err := copyOutXattrValue(t, valueAddr, size, value) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +// Fgetxattr implements Linux syscall fgetxattr(2). +func Fgetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := args[3].SizeT() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return 0, nil, err + } + + value, err := file.Getxattr(t, &vfs.GetxattrOptions{Name: name, Size: uint64(size)}) + if err != nil { + return 0, nil, err + } + n, err := copyOutXattrValue(t, valueAddr, size, value) + if err != nil { + return 0, nil, err + } + return uintptr(n), nil, nil +} + +// Setxattr implements Linux syscall setxattr(2). +func Setxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, setxattr(t, args, followFinalSymlink) +} + +// Lsetxattr implements Linux syscall lsetxattr(2). +func Lsetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, setxattr(t, args, nofollowFinalSymlink) +} + +func setxattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSymlink shouldFollowFinalSymlink) error { + pathAddr := args[0].Pointer() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := args[3].SizeT() + flags := args[4].Int() + + if flags&^(linux.XATTR_CREATE|linux.XATTR_REPLACE) != 0 { + return syserror.EINVAL + } + + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, shouldFollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return err + } + value, err := copyInXattrValue(t, valueAddr, size) + if err != nil { + return err + } + + return t.Kernel().VFS().SetxattrAt(t, t.Credentials(), &tpop.pop, &vfs.SetxattrOptions{ + Name: name, + Value: value, + Flags: uint32(flags), + }) +} + +// Fsetxattr implements Linux syscall fsetxattr(2). +func Fsetxattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + nameAddr := args[1].Pointer() + valueAddr := args[2].Pointer() + size := args[3].SizeT() + flags := args[4].Int() + + if flags&^(linux.XATTR_CREATE|linux.XATTR_REPLACE) != 0 { + return 0, nil, syserror.EINVAL + } + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return 0, nil, err + } + value, err := copyInXattrValue(t, valueAddr, size) + if err != nil { + return 0, nil, err + } + + return 0, nil, file.Setxattr(t, &vfs.SetxattrOptions{ + Name: name, + Value: value, + Flags: uint32(flags), + }) +} + +// Removexattr implements Linux syscall removexattr(2). +func Removexattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, removexattr(t, args, followFinalSymlink) +} + +// Lremovexattr implements Linux syscall lremovexattr(2). +func Lremovexattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + return 0, nil, removexattr(t, args, nofollowFinalSymlink) +} + +func removexattr(t *kernel.Task, args arch.SyscallArguments, shouldFollowFinalSymlink shouldFollowFinalSymlink) error { + pathAddr := args[0].Pointer() + nameAddr := args[1].Pointer() + + path, err := copyInPath(t, pathAddr) + if err != nil { + return err + } + tpop, err := getTaskPathOperation(t, linux.AT_FDCWD, path, disallowEmptyPath, shouldFollowFinalSymlink) + if err != nil { + return err + } + defer tpop.Release(t) + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return err + } + + return t.Kernel().VFS().RemovexattrAt(t, t.Credentials(), &tpop.pop, name) +} + +// Fremovexattr implements Linux syscall fremovexattr(2). +func Fremovexattr(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) { + fd := args[0].Int() + nameAddr := args[1].Pointer() + + file := t.GetFileVFS2(fd) + if file == nil { + return 0, nil, syserror.EBADF + } + defer file.DecRef(t) + + name, err := copyInXattrName(t, nameAddr) + if err != nil { + return 0, nil, err + } + + return 0, nil, file.Removexattr(t, name) +} + +func copyInXattrName(t *kernel.Task, nameAddr usermem.Addr) (string, error) { + name, err := t.CopyInString(nameAddr, linux.XATTR_NAME_MAX+1) + if err != nil { + if err == syserror.ENAMETOOLONG { + return "", syserror.ERANGE + } + return "", err + } + if len(name) == 0 { + return "", syserror.ERANGE + } + return name, nil +} + +func copyOutXattrNameList(t *kernel.Task, listAddr usermem.Addr, size uint, names []string) (int, error) { + if size > linux.XATTR_LIST_MAX { + size = linux.XATTR_LIST_MAX + } + var buf bytes.Buffer + for _, name := range names { + buf.WriteString(name) + buf.WriteByte(0) + } + if size == 0 { + // Return the size that would be required to accomodate the list. + return buf.Len(), nil + } + if buf.Len() > int(size) { + if size >= linux.XATTR_LIST_MAX { + return 0, syserror.E2BIG + } + return 0, syserror.ERANGE + } + return t.CopyOutBytes(listAddr, buf.Bytes()) +} + +func copyInXattrValue(t *kernel.Task, valueAddr usermem.Addr, size uint) (string, error) { + if size > linux.XATTR_SIZE_MAX { + return "", syserror.E2BIG + } + buf := make([]byte, size) + if _, err := t.CopyInBytes(valueAddr, buf); err != nil { + return "", err + } + return gohacks.StringFromImmutableBytes(buf), nil +} + +func copyOutXattrValue(t *kernel.Task, valueAddr usermem.Addr, size uint, value string) (int, error) { + if size > linux.XATTR_SIZE_MAX { + size = linux.XATTR_SIZE_MAX + } + if size == 0 { + // Return the size that would be required to accomodate the value. + return len(value), nil + } + if len(value) > int(size) { + if size >= linux.XATTR_SIZE_MAX { + return 0, syserror.E2BIG + } + return 0, syserror.ERANGE + } + return t.CopyOutBytes(valueAddr, gohacks.ImmutableBytesFromString(value)) +} |