Merge branch 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

[sfrench/cifs-2.6.git] / fs / notify / fanotify / fanotify.c

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index a34d7e003d7da6bb49aba0443fda337d4a48bf7a..e6fde1a5c0724912886e8c41e964942a543e49f1 100644 (file)
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -346,10 +346,16 @@ static __kernel_fsid_t fanotify_get_fsid(struct fsnotify_iter_info *iter_info)
        __kernel_fsid_t fsid = {};
 
        fsnotify_foreach_obj_type(type) {
+               struct fsnotify_mark_connector *conn;
+
                if (!fsnotify_iter_should_report_type(iter_info, type))
                        continue;
 
-               fsid = iter_info->marks[type]->connector->fsid;
+               conn = READ_ONCE(iter_info->marks[type]->connector);
+               /* Mark is just getting destroyed or created? */
+               if (!conn)
+                       continue;
+               fsid = conn->fsid;
                if (WARN_ON_ONCE(!fsid.val[0] && !fsid.val[1]))
                        continue;
                return fsid;
@@ -408,8 +414,12 @@ static int fanotify_handle_event(struct fsnotify_group *group,
                        return 0;
        }
 
-       if (FAN_GROUP_FLAG(group, FAN_REPORT_FID))
+       if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
                fsid = fanotify_get_fsid(iter_info);
+               /* Racing with mark destruction or creation? */
+               if (!fsid.val[0] && !fsid.val[1])
+                       return 0;
+       }
 
        event = fanotify_alloc_event(group, inode, mask, data, data_type,
                                     &fsid);