From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7D8383B27D1; Wed, 23 Sep 2026 14:40:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174411; cv=none; b=p1/Agf03B7ofDvizRueIN9Ype/FiTwdjd9CyweC5V+cXbJGWw5XU6K4shkAAJLIWHfC3B4l8ODAktbDGMuxwWRYz8E16Ji8CaI9QkJGrzzkhvXKp6MxiOJGrAJqnvCe41JD7C4mgDbfJOMlkMWy+CepDzt6i8Dz4a8IwXBZRU6s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790174411; c=relaxed/simple; bh=ghkUgZhRNxI6Wqo4tw/JtkUxEOLub8QzsYqYmczF8rg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mAI7kuYrxsKgxZx527K67zg2E/nlZW1fQijC8SHX5mnY7j3bGRVBM5bsNNVQirTBKIph/Q7gHtTZE3WrTwPMA/cDc7dCxmC9fUBS94eUtdfh76AVIecrxqAAxdg/288rbEigIodlB+w9oncD01MPNBoVE+EbooAcSEkR+w/IRhI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=oSXjxWaN; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="oSXjxWaN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D410F1F000FF; Wed, 23 Sep 2026 14:40:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790174410; bh=IhvcuVx3a9uo9kRJLenC0gRusDs11U+4ZjrUC1EcYcI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=oSXjxWaN73CnijPtrIm6g1z+hTB2fmG1dImvmpWePPAzKHSs2/98tlOYEM1GUVKDx WYcxoPasuvAa7HOdJOWJxhPfFj+D80Qx4an0gPmuNehwREEYdlqO9a+FHbchEJjnlS xDvIqbNgyh6lboGgXqTHqJ9eUn2qnwY6eSn7qE04= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+de3ee5362db09487ea37@syzkaller.appspotmail.com, Johannes Berg , Sasha Levin Subject: [PATCH 6.18 074/398] wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown Date: Wed, 23 Sep 2026 16:02:28 +0200 Message-ID: <20260923140645.350948912@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260923140643.441954610@linuxfoundation.org> References: <20260923140643.441954610@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Berg [ Upstream commit 4504f3960dc4501c73be9f99eabda2e26e9db41e ] On ifup, AP_VLAN interfaces get crypto_tx_tailroom_needed_cnt from the AP interface, but it's never decremented again unless the AP is also brought down. Thus, bringing the same AP_VLAN up again will increment the counter again and eventually hit the sanity check: WARN_ON_ONCE(sdata->crypto_tx_tailroom_needed_cnt != master->crypto_tx_tailroom_needed_cnt); Reset it on ifdown to avoid that. Assisted-by: LLM Fixes: f9dca80b98ca ("mac80211: fix AP_VLAN crypto tailroom calculation") Reported-by: syzbot+de3ee5362db09487ea37@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=de3ee5362db09487ea37 Link: https://patch.msgid.link/20260908122838.201719-14-johannes@sipsolutions.net Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- net/mac80211/iface.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 0c739af80f1ee..22ffae46f7cb7 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -609,6 +609,8 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata, bool going_do RCU_INIT_POINTER(sdata->vif.bss_conf.chanctx_conf, NULL); /* see comment in the default case below */ ieee80211_free_keys(sdata, true); + /* increased by AP value on ifup, so reset on ifdown */ + sdata->crypto_tx_tailroom_needed_cnt = 0; /* no need to tell driver */ break; case NL80211_IFTYPE_MONITOR: -- 2.53.0