Enable stat syscall support on arm64.

x86 and arm64 use a different stat struct in Linux
kernel, so the stat() syscall implementation has
to handle the file stat data separately.

Signed-off-by: Haibo Xu <haibo.xu@arm.com>
Change-Id: If3986e915a667362257a54e7fbbcc1fe18951015
COPYBARA_INTEGRATE_REVIEW=https://github.com/google/gvisor/pull/1493 from xiaobo55x:stat f15a216d9297eb9a96d2c483d396a9919145d7fa
PiperOrigin-RevId: 290274287

5 files changed, 162 insertions, 51 deletions

diff --git a/pkg/sentry/syscalls/linux/BUILD b/pkg/sentry/syscalls/linux/BUILD
index 430d796ba..917f74e07 100644
--- a/pkg/sentry/syscalls/linux/BUILD
+++ b/pkg/sentry/syscalls/linux/BUILD
@@ -42,6 +42,8 @@ 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",
diff --git a/pkg/sentry/syscalls/linux/linux64_arm64.go b/pkg/sentry/syscalls/linux/linux64_arm64.go
index 8c1b20911..c9629f6f3 100644
--- a/pkg/sentry/syscalls/linux/linux64_arm64.go
+++ b/pkg/sentry/syscalls/linux/linux64_arm64.go
@@ -61,6 +61,7 @@ var ARM64 = &kernel.SyscallTable{
 		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),
@@ -78,7 +79,9 @@ var ARM64 = &kernel.SyscallTable{
 		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),
@@ -112,6 +115,7 @@ var ARM64 = &kernel.SyscallTable{
 		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),
@@ -254,6 +258,8 @@ var ARM64 = &kernel.SyscallTable{
 		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),
@@ -299,6 +305,8 @@ var ARM64 = &kernel.SyscallTable{
 		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),
diff --git a/pkg/sentry/syscalls/linux/sys_stat.go b/pkg/sentry/syscalls/linux/sys_stat.go
index 5556bc276..69b17b799 100644
--- a/pkg/sentry/syscalls/linux/sys_stat.go
+++ b/pkg/sentry/syscalls/linux/sys_stat.go
@@ -16,7 +16,6 @@ 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"
@@ -125,56 +124,6 @@ func fstat(t *kernel.Task, f *fs.File, statAddr usermem.Addr) error {
 	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)
-	return err
-}
-
 // Statx implements linux syscall statx(2).
 func Statx(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
 	fd := args[0].Int()
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..58afb4a9a
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_stat_amd64.go
@@ -0,0 +1,75 @@
+// 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/binary"
+	"gvisor.dev/gvisor/pkg/sentry/fs"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/pkg/sentry/usermem"
+)
+
+// 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)
+	return err
+}
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..3e1251e0b
--- /dev/null
+++ b/pkg/sentry/syscalls/linux/sys_stat_arm64.go
@@ -0,0 +1,77 @@
+// 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/binary"
+	"gvisor.dev/gvisor/pkg/sentry/fs"
+	"gvisor.dev/gvisor/pkg/sentry/kernel"
+	"gvisor.dev/gvisor/pkg/sentry/usermem"
+)
+
+// 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))
+	// Mode (uint32)
+	b = binary.AppendUint32(b, usermem.ByteOrder, sattr.Type.LinuxType()|uint32(uattr.Perms.LinuxMode()))
+	// Nlink (uint32)
+	b = binary.AppendUint32(b, usermem.ByteOrder, uint32(uattr.Links))
+	// 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()))
+	// Rdev (uint64)
+	b = binary.AppendUint64(b, usermem.ByteOrder, uint64(linux.MakeDeviceID(sattr.DeviceFileMajor, sattr.DeviceFileMinor)))
+	// Padding (uint64)
+	b = binary.AppendUint64(b, usermem.ByteOrder, 0)
+	// Size (uint64)
+	b = binary.AppendUint64(b, usermem.ByteOrder, uint64(uattr.Size))
+	// Blksize (uint32)
+	b = binary.AppendUint32(b, usermem.ByteOrder, uint32(sattr.BlockSize))
+	// Padding (uint32)
+	b = binary.AppendUint32(b, usermem.ByteOrder, 0)
+	// 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)
+	return err
+}