[PATCH v5 7/7] locks: Disable LOCK_MAND support for MS_SHARELOCK mounts

Pavel Shilovsky
2013-04-09T12:36:46Z

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
---
fs/locks.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/fs/locks.c b/fs/locks.c
index 1402a43..a67857c 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1719,6 +1719,12 @@ SYSCALL_DEFINE2(flock, unsigned int, fd, unsigned int, cmd)
if (!f.file)
goto out;

+ /* Disable LOCK_MAND support for FS mounted with MS_SHARELOCK */
+ if (IS_SHARELOCK(f.file->f_path.dentry->d_inode)) {
+ error = -EPERM;
+ goto out;
+ }
+
can_sleep = !(cmd & LOCK_NB);
cmd &= ~LOCK_NB;
unlock = (cmd == LOCK_UN);
--
1.8.1.5