diff options
Diffstat (limited to 'pkg/sentry/vfs/file_description.go')
| -rw-r--r-- | pkg/sentry/vfs/file_description.go | 39 |
1 files changed, 33 insertions, 6 deletions
diff --git a/pkg/sentry/vfs/file_description.go b/pkg/sentry/vfs/file_description.go index 5321ac80a..dbf8425b4 100644 --- a/pkg/sentry/vfs/file_description.go +++ b/pkg/sentry/vfs/file_description.go @@ -454,10 +454,10 @@ type FileDescriptionImpl interface { UnlockBSD(ctx context.Context, uid lock.UniqueID) error // LockPOSIX tries to acquire a POSIX-style advisory file lock. - LockPOSIX(ctx context.Context, uid lock.UniqueID, t lock.LockType, start, length uint64, whence int16, block lock.Blocker) error + LockPOSIX(ctx context.Context, uid lock.UniqueID, t lock.LockType, r lock.LockRange, block lock.Blocker) error // UnlockPOSIX releases a POSIX-style advisory file lock. - UnlockPOSIX(ctx context.Context, uid lock.UniqueID, start, length uint64, whence int16) error + UnlockPOSIX(ctx context.Context, uid lock.UniqueID, ComputeLockRange lock.LockRange) error } // Dirent holds the information contained in struct linux_dirent64. @@ -802,13 +802,40 @@ func (fd *FileDescription) UnlockBSD(ctx context.Context) error { } // LockPOSIX locks a POSIX-style file range lock. -func (fd *FileDescription) LockPOSIX(ctx context.Context, uid lock.UniqueID, t lock.LockType, start, end uint64, whence int16, block lock.Blocker) error { - return fd.impl.LockPOSIX(ctx, uid, t, start, end, whence, block) +func (fd *FileDescription) LockPOSIX(ctx context.Context, uid lock.UniqueID, t lock.LockType, r lock.LockRange, block lock.Blocker) error { + return fd.impl.LockPOSIX(ctx, uid, t, r, block) } // UnlockPOSIX unlocks a POSIX-style file range lock. -func (fd *FileDescription) UnlockPOSIX(ctx context.Context, uid lock.UniqueID, start, end uint64, whence int16) error { - return fd.impl.UnlockPOSIX(ctx, uid, start, end, whence) +func (fd *FileDescription) UnlockPOSIX(ctx context.Context, uid lock.UniqueID, r lock.LockRange) error { + return fd.impl.UnlockPOSIX(ctx, uid, r) +} + +// ComputeLockRange computes the range of a file lock based on the given values. +func (fd *FileDescription) ComputeLockRange(ctx context.Context, start uint64, length uint64, whence int16) (lock.LockRange, error) { + var off int64 + switch whence { + case linux.SEEK_SET: + off = 0 + case linux.SEEK_CUR: + // Note that Linux does not hold any mutexes while retrieving the file + // offset, see fs/locks.c:flock_to_posix_lock and fs/locks.c:fcntl_setlk. + curOff, err := fd.Seek(ctx, 0, linux.SEEK_CUR) + if err != nil { + return lock.LockRange{}, err + } + off = curOff + case linux.SEEK_END: + stat, err := fd.Stat(ctx, StatOptions{Mask: linux.STATX_SIZE}) + if err != nil { + return lock.LockRange{}, err + } + off = int64(stat.Size) + default: + return lock.LockRange{}, syserror.EINVAL + } + + return lock.ComputeRange(int64(start), int64(length), off) } // A FileAsync sends signals to its owner when w is ready for IO. This is only |