From: Johannes Berg Date: Mon, 15 Apr 2019 09:39:33 +0000 (+0200) Subject: mac80211: don't attempt to rename ERR_PTR() debugfs dirs X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=517879147493a5e1df6b89a50f708f1133fcaddb;p=linux.git mac80211: don't attempt to rename ERR_PTR() debugfs dirs We need to dereference the directory to get its parent to be able to rename it, so it's clearly not safe to try to do this with ERR_PTR() pointers. Skip in this case. It seems that this is most likely what was causing the report by syzbot, but I'm not entirely sure as it didn't come with a reproducer this time. Cc: stable@vger.kernel.org Reported-by: syzbot+4ece1a28b8f4730547c9@syzkaller.appspotmail.com Signed-off-by: Johannes Berg --- diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c index cff0fb3578c9a..deb3faf083372 100644 --- a/net/mac80211/debugfs_netdev.c +++ b/net/mac80211/debugfs_netdev.c @@ -841,7 +841,7 @@ void ieee80211_debugfs_rename_netdev(struct ieee80211_sub_if_data *sdata) dir = sdata->vif.debugfs_dir; - if (!dir) + if (IS_ERR_OR_NULL(dir)) return; sprintf(buf, "netdev:%s", sdata->name);