Merge release-20200522.0-70-g7da69fe9 (automated)

3 files changed, 10 insertions, 10 deletions

diff --git a/pkg/abi/linux/linux_abi_autogen_unsafe.go b/pkg/abi/linux/linux_abi_autogen_unsafe.go
index 440f389f6..eb51edb55 100644
--- a/pkg/abi/linux/linux_abi_autogen_unsafe.go
+++ b/pkg/abi/linux/linux_abi_autogen_unsafe.go
@@ -124,12 +124,12 @@ func (s *Statx) UnmarshalBytes(src []byte) {
 // Packed implements marshal.Marshallable.Packed.
 //go:nosplit
 func (s *Statx) Packed() bool {
-    return s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed()
+    return s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed()
 }
 
 // MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.
 func (s *Statx) MarshalUnsafe(dst []byte) {
-    if s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
+    if s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() {
         safecopy.CopyIn(dst, unsafe.Pointer(s))
     } else {
         s.MarshalBytes(dst)
@@ -138,7 +138,7 @@ func (s *Statx) MarshalUnsafe(dst []byte) {
 
 // UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.
 func (s *Statx) UnmarshalUnsafe(src []byte) {
-    if s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() {
+    if s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() && s.Btime.Packed() {
         safecopy.CopyOut(unsafe.Pointer(s), src)
     } else {
         s.UnmarshalBytes(src)
@@ -148,7 +148,7 @@ func (s *Statx) UnmarshalUnsafe(src []byte) {
 // CopyOutN implements marshal.Marshallable.CopyOutN.
 //go:nosplit
 func (s *Statx) CopyOutN(task marshal.Task, addr usermem.Addr, limit int) (int, error) {
-    if !s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() && s.Atime.Packed() {
+    if !s.Atime.Packed() && s.Btime.Packed() && s.Ctime.Packed() && s.Mtime.Packed() {
         // Type Statx doesn't have a packed layout in memory, fall back to MarshalBytes.
         buf := task.CopyScratchBuffer(s.SizeBytes()) // escapes: okay.
         s.MarshalBytes(buf) // escapes: fallback.
diff --git a/pkg/sentry/fs/file.go b/pkg/sentry/fs/file.go
index 846252c89..2a278fbe3 100644
--- a/pkg/sentry/fs/file.go
+++ b/pkg/sentry/fs/file.go
@@ -310,7 +310,6 @@ func (f *File) Writev(ctx context.Context, src usermem.IOSequence) (int64, error
 	if !f.mu.Lock(ctx) {
 		return 0, syserror.ErrInterrupted
 	}
-
 	unlockAppendMu := f.Dirent.Inode.lockAppendMu(f.Flags().Append)
 	// Handle append mode.
 	if f.Flags().Append {
@@ -355,7 +354,6 @@ func (f *File) Pwritev(ctx context.Context, src usermem.IOSequence, offset int64
 	// offset."
 	unlockAppendMu := f.Dirent.Inode.lockAppendMu(f.Flags().Append)
 	defer unlockAppendMu()
-
 	if f.Flags().Append {
 		if err := f.offsetForAppend(ctx, &offset); err != nil {
 			return 0, err
@@ -374,9 +372,10 @@ func (f *File) Pwritev(ctx context.Context, src usermem.IOSequence, offset int64
 	return f.FileOperations.Write(ctx, f, src, offset)
 }
 
-// offsetForAppend sets the given offset to the end of the file.
+// offsetForAppend atomically sets the given offset to the end of the file.
 //
-// Precondition: the file.Dirent.Inode.appendMu mutex should be held for writing.
+// Precondition: the file.Dirent.Inode.appendMu mutex should be held for
+// writing.
 func (f *File) offsetForAppend(ctx context.Context, offset *int64) error {
 	uattr, err := f.Dirent.Inode.UnstableAttr(ctx)
 	if err != nil {
@@ -386,7 +385,7 @@ func (f *File) offsetForAppend(ctx context.Context, offset *int64) error {
 	}
 
 	// Update the offset.
-	*offset = uattr.Size
+	atomic.StoreInt64(offset, uattr.Size)
 
 	return nil
 }
diff --git a/pkg/sentry/fs/fs.go b/pkg/sentry/fs/fs.go
index bdba6efe5..d2dbff268 100644
--- a/pkg/sentry/fs/fs.go
+++ b/pkg/sentry/fs/fs.go
@@ -42,9 +42,10 @@
 //     Dirent.dirMu
 //       Dirent.mu
 //         DirentCache.mu
-//         Locks in InodeOperations implementations or overlayEntry
 //         Inode.Watches.mu (see `Inotify` for other lock ordering)
 //         MountSource.mu
+//         Inode.appendMu
+//           Locks in InodeOperations implementations or overlayEntry
 //
 // If multiple Dirent or MountSource locks must be taken, locks in the parent must be
 // taken before locks in their children.