inotify/dnotify: should_send_event shouldn't match on FS_EVENT_ON_CHILD

inotify and dnotify will both indicate that they want any event which came
from a child inode.  The fix is to mask off FS_EVENT_ON_CHILD when deciding
if inotify or dnotify is interested in a given event.

Signed-off-by: Eric Paris <eparis@redhat.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index f11d75f02368..ec2f7bd76818 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -137,14 +137,16 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, const
         struct fsnotify_group *group;
         struct fsnotify_event *event = NULL;
         int idx;
+        /* global tests shouldn't care about events on child only the specific event */
+        __u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
 
         if (list_empty(&fsnotify_groups))
                 return;
 
-        if (!(mask & fsnotify_mask))
+        if (!(test_mask & fsnotify_mask))
                 return;
 
-        if (!(mask & to_tell->i_fsnotify_mask))
+        if (!(test_mask & to_tell->i_fsnotify_mask))
                 return;
         /*
          * SRCU!!  the groups list is very very much read only and the path is
@@ -153,7 +155,7 @@ void fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is, const
          */
         idx = srcu_read_lock(&fsnotify_grp_srcu);
         list_for_each_entry_rcu(group, &fsnotify_groups, group_list) {
-                if (mask & group->mask) {
+                if (test_mask & group->mask) {
                         if (!group->ops->should_send_event(group, to_tell, mask))
                                 continue;
                         if (!event) {