From d3bc0fa8411c35194f99046157e2e26fe60e1d91 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 20 Aug 2018 13:55:45 +0200 Subject: [PATCH] fsnotify: fix false positive warning on inode delete When inode is getting deleted and someone else holds reference to a mark attached to the inode, we just detach the connector from the inode. In that case fsnotify_put_mark() called from fsnotify_destroy_marks() will decide to recalculate mask for the inode and __fsnotify_recalc_mask() will WARN about invalid connector type: WARNING: CPU: 1 PID: 12015 at fs/notify/mark.c:139 __fsnotify_recalc_mask+0x2d7/0x350 fs/notify/mark.c:139 Actually there's no reason to warn about detached connector in __fsnotify_recalc_mask() so just silently skip updating the mask in such case. Reported-by: syzbot+c34692a51b9a6ca93540@syzkaller.appspotmail.com Fixes: 3ac70bfcde81 ("fsnotify: add helper to get mask from connector") Signed-off-by: Jan Kara --- fs/notify/mark.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/notify/mark.c b/fs/notify/mark.c index 05506d60131c..59cdb27826de 100644 --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -132,13 +132,13 @@ static void __fsnotify_recalc_mask(struct fsnotify_mark_connector *conn) struct fsnotify_mark *mark; assert_spin_locked(&conn->lock); + /* We can get detached connector here when inode is getting unlinked. */ + if (!fsnotify_valid_obj_type(conn->type)) + return; hlist_for_each_entry(mark, &conn->list, obj_list) { if (mark->flags & FSNOTIFY_MARK_FLAG_ATTACHED) new_mask |= mark->mask; } - if (WARN_ON(!fsnotify_valid_obj_type(conn->type))) - return; - *fsnotify_conn_mask_p(conn) = new_mask; }