Re: [syzbot] [fs?] KASAN: slab-use-after-free Read in lockref_get

[Hillf Danton]

On Mon, 15 Jul 2024 19:02:19 -0700
> syzbot found the following issue on:
> 
> HEAD commit:    58f9416d413a Merge branch 'ice-support-to-dump-phy-config-..
> git tree:       net-next
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=16ed24b5980000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git  58f9416d413a

--- x/net/mac80211/debugfs_sta.c
+++ y/net/mac80211/debugfs_sta.c
@@ -1284,6 +1284,12 @@ void ieee80211_sta_debugfs_add(struct st
 
 void ieee80211_sta_debugfs_remove(struct sta_info *sta)
 {
+	struct ieee80211_sub_if_data *sdata = sta->sdata;
+
+	if (!sdata->debugfs.subdir_stations)
+		return;
+	if (!sdata->vif.debugfs_dir)
+		return;
 	debugfs_remove_recursive(sta->debugfs_dir);
 	sta->debugfs_dir = NULL;
 }
--