summaryrefslogtreecommitdiffhomepage
path: root/pkg/sentry/syscalls
diff options
context:
space:
mode:
authorZach Koopmans <zkoopmans@google.com>2020-07-01 13:13:04 -0700
committergVisor bot <gvisor-bot@google.com>2020-07-01 13:14:44 -0700
commit6a90c88b97481a6d81b05f09d5c8ed7158225dd5 (patch)
treee22db333e636d2dae96bcbf4f36d48eb81df3d0d /pkg/sentry/syscalls
parent68e1c870d3ef5db71226927aee703f2fba61cab7 (diff)
Port fallocate to VFS2.
PiperOrigin-RevId: 319283715
Diffstat (limited to 'pkg/sentry/syscalls')
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/filesystem.go50
-rw-r--r--pkg/sentry/syscalls/linux/vfs2/vfs2.go2
2 files changed, 51 insertions, 1 deletions
diff --git a/pkg/sentry/syscalls/linux/vfs2/filesystem.go b/pkg/sentry/syscalls/linux/vfs2/filesystem.go
index 5dac77e4d..b12b5967b 100644
--- a/pkg/sentry/syscalls/linux/vfs2/filesystem.go
+++ b/pkg/sentry/syscalls/linux/vfs2/filesystem.go
@@ -18,6 +18,7 @@ import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/kernel"
+ "gvisor.dev/gvisor/pkg/sentry/limits"
"gvisor.dev/gvisor/pkg/sentry/vfs"
"gvisor.dev/gvisor/pkg/syserror"
"gvisor.dev/gvisor/pkg/usermem"
@@ -239,6 +240,55 @@ func renameat(t *kernel.Task, olddirfd int32, oldpathAddr usermem.Addr, newdirfd
})
}
+// 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()
+
+ 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
+ }
+
+ return 0, nil, file.Impl().Allocate(t, mode, uint64(offset), uint64(length))
+
+ // File length modified, generate notification.
+ // TODO(gvisor.dev/issue/1479): Reenable when Inotify is ported.
+ // file.Dirent.InotifyEvent(linux.IN_MODIFY, 0)
+}
+
// Rmdir implements Linux syscall rmdir(2).
func Rmdir(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
pathAddr := args[0].Pointer()
diff --git a/pkg/sentry/syscalls/linux/vfs2/vfs2.go b/pkg/sentry/syscalls/linux/vfs2/vfs2.go
index 9e60c4a1c..8f497ecc7 100644
--- a/pkg/sentry/syscalls/linux/vfs2/vfs2.go
+++ b/pkg/sentry/syscalls/linux/vfs2/vfs2.go
@@ -138,7 +138,7 @@ func Override() {
s.Table[282] = syscalls.Supported("signalfd", Signalfd)
s.Table[283] = syscalls.Supported("timerfd_create", TimerfdCreate)
s.Table[284] = syscalls.Supported("eventfd", Eventfd)
- delete(s.Table, 285) // fallocate
+ 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)