From b481e64e4498e2c053d5954f546ee02338f6ab63 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Tue, 8 Sep 2026 14:28:16 +0200 Subject: [PATCH] wifi: mac80211: don't RCU-dereference the mesh CSA settings we just set In the error path of ieee80211_mesh_csa_beacon() the settings that were just assigned are read back with rcu_dereference(), which lockdep then complains about. There's no need to read the pointer at all, tmp_csa_settings still is the right value anyway. Assisted-by: LLM Fixes: b8456a14e9d2 ("{nl,cfg,mac}80211: implement mesh channel switch userspace API") Reported-by: syzbot+b59873f5699e941717ca@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=b59873f5699e941717ca Link: https://patch.msgid.link/20260908122838.201719-17-johannes@sipsolutions.net Signed-off-by: Johannes Berg --- net/mac80211/mesh.c | 1 - 1 file changed, 1 deletion(-) diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index bed7ac838250..a35e2d5870b6 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -1559,7 +1559,6 @@ int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata, ret = ieee80211_mesh_rebuild_beacon(sdata); if (ret) { - tmp_csa_settings = rcu_dereference(ifmsh->csa); RCU_INIT_POINTER(ifmsh->csa, NULL); kfree_rcu(tmp_csa_settings, rcu_head); return ret;