3 files changed, 9 insertions, 4 deletions

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index b04f88eed09..f35794b97e8 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -92,7 +92,11 @@ static int fanotify_get_response_from_access(struct fsnotify_group *group,
 
         pr_debug("%s: group=%p event=%p\n", __func__, group, event);
 
-        wait_event(group->fanotify_data.access_waitq, event->response);
+        wait_event(group->fanotify_data.access_waitq, event->response ||
+                                atomic_read(&group->fanotify_data.bypass_perm));
+
+        if (!event->response) /* bypass_perm set */
+                return 0;
 
         /* userspace responded, convert to something usable */
         spin_lock(&event->lock);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 480434c5ee5..01fffe62a2d 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -200,7 +200,7 @@ static int prepare_for_access_response(struct fsnotify_group *group,
 
         mutex_lock(&group->fanotify_data.access_mutex);
 
-        if (group->fanotify_data.bypass_perm) {
+        if (atomic_read(&group->fanotify_data.bypass_perm)) {
                 mutex_unlock(&group->fanotify_data.access_mutex);
                 kmem_cache_free(fanotify_response_event_cache, re);
                 event->response = FAN_ALLOW;
@@ -390,7 +390,7 @@ static int fanotify_release(struct inode *ignored, struct file *file)
 
         mutex_lock(&group->fanotify_data.access_mutex);
 
-        group->fanotify_data.bypass_perm = true;
+        atomic_inc(&group->fanotify_data.bypass_perm);
 
         list_for_each_entry_safe(re, lre, &group->fanotify_data.access_list, list) {
                 pr_debug("%s: found group=%p re=%p event=%p\n", __func__, group,
@@ -703,6 +703,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
         mutex_init(&group->fanotify_data.access_mutex);
         init_waitqueue_head(&group->fanotify_data.access_waitq);
         INIT_LIST_HEAD(&group->fanotify_data.access_list);
+        atomic_set(&group->fanotify_data.bypass_perm, 0);
 #endif
         switch (flags & FAN_ALL_CLASS_BITS) {
         case FAN_CLASS_NOTIF:
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 0a68f924f06..7380763595d 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -166,7 +166,7 @@ struct fsnotify_group {
                         struct mutex access_mutex;
                         struct list_head access_list;
                         wait_queue_head_t access_waitq;
-                        bool bypass_perm; /* protected by access_mutex */
+                        atomic_t bypass_perm;
 #endif /* CONFIG_FANOTIFY_ACCESS_PERMISSIONS */
                         int f_flags;
                         unsigned int max_marks;