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 2FDA74CC63A; Wed, 30 Sep 2026 18:12:08 +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=1790791929; cv=none; b=GhbzZc9xKzaJK5kTwXr0Lz631LK6z6dEkXxLfsCaFlxxToE1E5r4t8AKHR6PVcYxs2XRBBMcSEh1REQgeMjn/seZmKRqVooVIZ8D9qejYEEX6K98oAJV5fdw09uSuckTb4T75OYbMDyTjWAR2vBcmRfZw0VYkUeLzPD2l4gNtjE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790791929; c=relaxed/simple; bh=bzeNdJrwWCXQi19ggnb94p+YJk/pU2LswlAQCUR47dM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=G9d35sdyqKF30+zruqucIEcSYDyp+Hq9HF+eHFsva7cCRsXf1gnSEySahzWyFjld6m/OtNRLecA9OsMD4aj4EHeatix0kEmZAJ7Xc3TQo4ijKfEeVDr0yG1W+kKwbWCvX/qqhVo/zKE/afeYyJdtAQysf1yJnZ3GJmObu6f+nlA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=RnsmRvR/; 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="RnsmRvR/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D2E51F000FF; Wed, 30 Sep 2026 18:12:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790791928; bh=H4niQcnGHv8a4TulfgZjbIeRTndNUYa6UPduXFwWeAU=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RnsmRvR/YCjVEHnO8guLIggAbzAjSXLTFM6PK9ZVBqiz0I4iNvyCARJlICm3i0S1b pjrgFS5j1mlldD4j/fyQJvBE0zXKAi6AtS5zIkBWd/i8m3/DykRWQOLfPjLuOQ7jhk oe4O7/RWMqpLcpirRhI5hb7NlDA02xY1CYyNTX4c= 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 5.15 476/752] wifi: mac80211: reset the AP_VLAN tailroom counter on ifdown Date: Wed, 30 Sep 2026 17:25:46 +0200 Message-ID: <20260930152408.573320142@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260930152358.131179731@linuxfoundation.org> References: <20260930152358.131179731@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 5.15-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 3b2d51df5d947..13a1e119dce0e 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -512,6 +512,8 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata, bool going_do RCU_INIT_POINTER(sdata->vif.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