diff options
Diffstat (limited to 'pkg/sentry/fs/file.go')
| -rw-r--r-- | pkg/sentry/fs/file.go | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/pkg/sentry/fs/file.go b/pkg/sentry/fs/file.go index 55ffe6c0c..8e1f5674d 100644 --- a/pkg/sentry/fs/file.go +++ b/pkg/sentry/fs/file.go @@ -310,9 +310,11 @@ func (f *File) Writev(ctx context.Context, src usermem.IOSequence) (int64, error return 0, syserror.ErrInterrupted } + unlockAppendMu := f.Dirent.Inode.lockAppendMu(f.Flags().Append) // Handle append mode. if f.Flags().Append { if err := f.offsetForAppend(ctx, &f.offset); err != nil { + unlockAppendMu() f.mu.Unlock() return 0, err } @@ -322,6 +324,7 @@ func (f *File) Writev(ctx context.Context, src usermem.IOSequence) (int64, error limit, ok := f.checkLimit(ctx, f.offset) switch { case ok && limit == 0: + unlockAppendMu() f.mu.Unlock() return 0, syserror.ErrExceedsFileSizeLimit case ok: @@ -333,6 +336,7 @@ func (f *File) Writev(ctx context.Context, src usermem.IOSequence) (int64, error if n >= 0 && !f.flags.NonSeekable { atomic.StoreInt64(&f.offset, f.offset+n) } + unlockAppendMu() f.mu.Unlock() return n, err } @@ -348,13 +352,11 @@ func (f *File) Pwritev(ctx context.Context, src usermem.IOSequence, offset int64 // However, on Linux, if a file is opened with O_APPEND, pwrite() // appends data to the end of the file, regardless of the value of // offset." + unlockAppendMu := f.Dirent.Inode.lockAppendMu(f.Flags().Append) + defer unlockAppendMu() + if f.Flags().Append { - if !f.mu.Lock(ctx) { - return 0, syserror.ErrInterrupted - } - defer f.mu.Unlock() if err := f.offsetForAppend(ctx, &offset); err != nil { - f.mu.Unlock() return 0, err } } @@ -373,7 +375,7 @@ func (f *File) Pwritev(ctx context.Context, src usermem.IOSequence, offset int64 // offsetForAppend sets the given offset to the end of the file. // -// Precondition: the underlying file mutex should be held. +// 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 { |