[PATCH 3.12 54/60] nlm: Ensure callback code also checks that the files match

[Jiri Slaby]

From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 251af29c320d86071664f02c76f0d063a19fefdf upstream.

It is not sufficient to just check that the lock pids match when
granting a callback, we also need to ensure that we're granting
the callback on the right file.

Reported-by: Pankaj Singh <psingh.ait@xxxxxxxxx>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
 include/linux/lockd/lockd.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h
index 0adf073f13b3..669af5eaa898 100644
--- a/include/linux/lockd/lockd.h
+++ b/include/linux/lockd/lockd.h
@@ -355,7 +355,8 @@ static inline int nlm_privileged_requester(const struct svc_rqst *rqstp)
 static inline int nlm_compare_locks(const struct file_lock *fl1,
 				    const struct file_lock *fl2)
 {
-	return	fl1->fl_pid   == fl2->fl_pid
+	return file_inode(fl1->fl_file) == file_inode(fl2->fl_file)
+	     && fl1->fl_pid   == fl2->fl_pid
 	     && fl1->fl_owner == fl2->fl_owner
 	     && fl1->fl_start == fl2->fl_start
 	     && fl1->fl_end   == fl2->fl_end
-- 
2.12.0