[PATCH 4.19 003/110] inotify: Fix fsnotify_mark refcount leak in inotify_update_existing_watch()

From: Greg Kroah-Hartman
Date: Thu Apr 18 2019 - 13:58:51 EST


[ Upstream commit 62c9d2674b31d4c8a674bee86b7edc6da2803aea ]

Commit 4d97f7d53da7dc83 ("inotify: Add flag IN_MASK_CREATE for
inotify_add_watch()") forgot to call fsnotify_put_mark() with
IN_MASK_CREATE after fsnotify_find_mark()

Fixes: 4d97f7d53da7dc83 ("inotify: Add flag IN_MASK_CREATE for inotify_add_watch()")
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@xxxxxxxxxx>
Signed-off-by: Jan Kara <jack@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/notify/inotify/inotify_user.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 780bba695453..97a51690338e 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -519,8 +519,10 @@ static int inotify_update_existing_watch(struct fsnotify_group *group,
fsn_mark = fsnotify_find_mark(&inode->i_fsnotify_marks, group);
if (!fsn_mark)
return -ENOENT;
- else if (create)
- return -EEXIST;
+ else if (create) {
+ ret = -EEXIST;
+ goto out;
+ }

i_mark = container_of(fsn_mark, struct inotify_inode_mark, fsn_mark);

@@ -548,6 +550,7 @@ static int inotify_update_existing_watch(struct fsnotify_group *group,
/* return the wd */
ret = i_mark->wd;

+out:
/* match the get from fsnotify_find_mark() */
fsnotify_put_mark(fsn_mark);

--
2.19.1