fanotify: only destroy mark when both mask and ignored_mask are cleared

In fanotify_mark_remove_from_mask() a mark is destroyed if only one of
both bitmasks (mask or ignored_mask) of a mark is cleared.  However the
other mask may still be set and contain information that should not be
lost.  So only destroy a mark if both masks are cleared.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index bff8567aa42d1b04cd85e6f2863de3b1f4d9a2db..25adb6d1b3db8000dd6679170b2c702a41234bce 100644 (file)
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -497,10 +497,9 @@ static __u32 fanotify_mark_remove_from_mask(struct fsnotify_mark *fsn_mark,
                oldmask = fsn_mark->ignored_mask;
                fsnotify_set_mark_ignored_mask_locked(fsn_mark, (oldmask & ~mask));
        }
+       *destroy = !(fsn_mark->mask | fsn_mark->ignored_mask);
        spin_unlock(&fsn_mark->lock);
 
-       *destroy = !(oldmask & ~mask);
-
        return mask & oldmask;
 }