fsnotify: reset used_inode and used_vfsmount on each pass

The fsnotify main loop has 2 booleans which tell if a particular mark was
sent to the listeners or if it should be processed in the next pass.  The
problem is that the booleans were not reset on each traversal of the loop.
So marks could get skipped even when they were not sent to the notifiers.
Reported-by: Tvrtko Ursulin <tvrtko.ursulin@sophos.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

fs/notify/fsnotify.c

@@ -220,7 +220,7 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
 	struct fsnotify_event *event = NULL;
 	struct vfsmount *mnt;
 	int idx, ret = 0;
-	bool used_inode = false, used_vfsmount = false;
+	bool used_inode, used_vfsmount;
 	/* global tests shouldn't care about events on child only the specific event */
 	__u32 test_mask = (mask & ~FS_EVENT_ON_CHILD);
 
@@ -261,6 +261,8 @@ int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
 	}
 
 	while (inode_node || vfsmount_node) {
+		used_inode = used_vfsmount = false;
+
 		if (inode_node) {
 			inode_mark = hlist_entry(srcu_dereference(inode_node, &fsnotify_mark_srcu),
 						 struct fsnotify_mark, i.i_list);