fanotify: ignored_mask to ignore events

When fanotify receives an event it will check event->mask & ~ignored_mask.
If no bits are left the event will not be sent.

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

1 files changed, 23 insertions, 14 deletions

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index f6900022f69e..060b177146e8 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -100,31 +100,39 @@ static int fanotify_handle_event(struct fsnotify_group *group, struct fsnotify_e
 }
 
 static bool should_send_vfsmount_event(struct fsnotify_group *group, struct vfsmount *mnt,
-                                       __u32 mask)
+                                       struct inode *inode, __u32 mask)
 {
-        struct fsnotify_mark *fsn_mark;
-        bool send;
+        struct fsnotify_mark *mnt_mark;
+        struct fsnotify_mark *inode_mark;
 
         pr_debug("%s: group=%p vfsmount=%p mask=%x\n",
                  __func__, group, mnt, mask);
 
-        fsn_mark = fsnotify_find_vfsmount_mark(group, mnt);
-        if (!fsn_mark)
+        mnt_mark = fsnotify_find_vfsmount_mark(group, mnt);
+        if (!mnt_mark)
                 return false;
 
-        send = (mask & fsn_mark->mask);
+        mask &= mnt_mark->mask;
+        mask &= ~mnt_mark->ignored_mask;
+
+        if (mask) {
+                inode_mark = fsnotify_find_inode_mark(group, inode);
+                if (inode_mark) {
+                        mask &= ~inode_mark->ignored_mask;
+                        fsnotify_put_mark(inode_mark);
+                }
+        }
 
         /* find took a reference */
-        fsnotify_put_mark(fsn_mark);
+        fsnotify_put_mark(mnt_mark);
 
-        return send;
+        return mask;
 }
 
 static bool should_send_inode_event(struct fsnotify_group *group, struct inode *inode,
                                     __u32 mask)
 {
         struct fsnotify_mark *fsn_mark;
-        bool send;
 
         pr_debug("%s: group=%p inode=%p mask=%x\n",
                  __func__, group, inode, mask);
@@ -137,20 +145,21 @@ static bool should_send_inode_event(struct fsnotify_group *group, struct inode *
          * events on the child, don't send it! */
         if ((mask & FS_EVENT_ON_CHILD) &&
             !(fsn_mark->mask & FS_EVENT_ON_CHILD)) {
-                send = false;
+                mask = 0;
         } else {
                 /*
                  * We care about children, but do we care about this particular
                  * type of event?
                  */
-                mask = (mask & ~FS_EVENT_ON_CHILD);
-                send = (fsn_mark->mask & mask);
+                mask &= ~FS_EVENT_ON_CHILD;
+                mask &= fsn_mark->mask;
+                mask &= ~fsn_mark->ignored_mask;
         }
 
         /* find took a reference */
         fsnotify_put_mark(fsn_mark);
 
-        return send;
+        return mask;
 }
 
 static bool fanotify_should_send_event(struct fsnotify_group *group, struct inode *to_tell,
@@ -170,7 +179,7 @@ static bool fanotify_should_send_event(struct fsnotify_group *group, struct inod
                 return false;
 
         if (mnt)
-                return should_send_vfsmount_event(group, mnt, mask);
+                return should_send_vfsmount_event(group, mnt, to_tell, mask);
         else
                 return should_send_inode_event(group, to_tell, mask);
 }