From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-dy1-f182.google.com (mail-dy1-f182.google.com [74.125.82.182]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 238D02EB5CD for ; Wed, 24 Jun 2026 05:33:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.82.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782279183; cv=none; b=FuoBJC7/K0YnpAKsIPm9TuLJBZa3xtWJx4y3QiNiSxJarRJpoXPNm8717b48HYlUipPpPuFCwTRg3h4Velhh9ZWHzTDQHzw/out697dlz0loQHHVYsU5ijLEXDBBfAtH865L1En9WOwG8SV6Q+MObputjJC30e4SiPB9CNVRxv0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782279183; c=relaxed/simple; bh=nrtaw2ep0DCwDiNk68McCNWo/BLbRmzKgeIJm3iLoCE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=VyKIQJpK3aCz+ukB5+qF7qmR/wlCcZ5CIoPOCmc38kJ7R3Q1q66JEIU4AW5uqDkYLuG5Bfphq9ferL46hb3b5eMGMVUrd6XL2DqIcqlSiLnAu6vEFxuP5nIjGcHTT0qlJ/rIluKlB/ALegqBu3WbTPQcoMZgt6AtQxZnfvBGFcQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=UlTGWQWy; arc=none smtp.client-ip=74.125.82.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="UlTGWQWy" Received: by mail-dy1-f182.google.com with SMTP id 5a478bee46e88-30c6836fea9so402885eec.1 for ; Tue, 23 Jun 2026 22:33:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782279180; x=1782883980; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=sOavHhXXwzowPYsq4xGyB1KuD7Tfjz+llQKByGEFJQo=; b=UlTGWQWyJ+Acfv62bVw9aW+LlqLaie01vPFPQsvO1ruK45g/w+V3eVj8RmtX14mVMo k8FqaviXfHY2KuooVq6c9HlF3uz8eYpIVxKZAdo4QfGy4kPFZf4EVQ/6aOELa1gHzluf WYfGTW5qpfkW4Q/uArdUNmhQUn4+hPPgpCM+eemP6UFKnKWJdDHnALmffiIc1HujF28b EtSKKK24GHHEa6lnYi5amLy6KHmJ5ltM8pPJaBbrw/0/f6PXWJXSNdNA8VrsL09YthRA gzXsP2tL1pp5nmZCTnwS5nngZ2zvQf074hWNK/3PNEMnzK4FaneNfDyumnpwNkB1icaW WqcA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782279180; x=1782883980; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=sOavHhXXwzowPYsq4xGyB1KuD7Tfjz+llQKByGEFJQo=; b=UpPSN5VF4WkUxaIKJNO4pRAerGhMskZ5AuX08k2PiefGOApehuboV0vTBdG+JqyXFv /qX+rjtV78n+VXEcfJmBPcpT42bvmTUrIc0iccqe2m9aQg5Xs9CX8m2uwP+nf0dAQkCw UQuTIcWeKesdo1qOIpJ3wnfyxNUk26NZd4bBQFlRCdp0/7vH5YVlpn4RnNlbFP6FRwet OigWNzsS3gt1Vrw/Z9/6GSe/ZfDhzT3/KrXJ+SHBMfILN4doeHfPiVs4jAKmcKgTHHI+ RMj9CloTRGcUnvMIpYGJaDbnKjKnmop9ohBGPY9bR0if9VNubLXAjJXpZNZJ4TrnUL7b moKA== X-Gm-Message-State: AOJu0YxW4EcPa2zYjQbsBFXolsliMVV/WfJ+z9ap22FkhQIY0gtSGIdn P7xqiijCtVkNWaO4CW63tGDNtJDKfoAKYo48hhzehrUWdWpz0pLnUQqV X-Gm-Gg: AfdE7cmBb3vEr4UrcXbsXUz/tnsUj+F+KrWE/OcOUfeF00XDOZYsv8b1tWHNc+vjWXu eRGa3bxvlf5uXU8vTrDNoVWRAdNFLhwlEIgYdtQBqqjab9Onr1dKFs3Rq+k62aKCiv/p5Oa8WJA JK9yaUBFKrWw6mOSEI90Q6siN6UT4eIrRWMROQdGozGANC7iwq2QmK63cRhLv09t+qu0X4geX7z 62F/4G0S+XV+x5ZXjphKuPPY4ydLo5/OIhMjo63ej3Pvnmm5EcI8UFL9yzi7m7WljVgI1ga6GSq NSTspJenN9YQ4tC3nZ1Iq0ptzKPBScEz9aNcclkIx+7zcWAxiQs5sesNJ2T+MxYKkvBq2ewGlJB FeiUg88xYJHllnlXJFRzA/XLHMCEoPSa/AK9ERJWziyoXobsKHfOVLkF0X3kC/FGVxEoJQWWX8z HvM3oNEBKq2BcNi7GJr+Zei3iNjifWKhSzkt/ffp69 X-Received: by 2002:a05:7300:80cc:b0:30c:1fb5:94b1 with SMTP id 5a478bee46e88-30c5553657amr6680575eec.6.1782279180167; Tue, 23 Jun 2026 22:33:00 -0700 (PDT) Received: from localhost.localdomain ([192.197.201.174]) by smtp.gmail.com with ESMTPSA id 5a478bee46e88-30c1ba1c32csm22955775eec.6.2026.06.23.22.32.58 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Tue, 23 Jun 2026 22:32:59 -0700 (PDT) From: hewei-gikaku To: Christian Lamparter Cc: linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, HE WEI , syzbot+5c1ca6ccaa1215781cac@syzkaller.appspotmail.com Subject: [PATCH] wifi: carl9170: bail out on invalid command response to fix stack-out-of-bounds write Date: Wed, 24 Jun 2026 14:32:45 +0900 Message-ID: <20260624053246.74617-1-skyexpoc@gmail.com> X-Mailer: git-send-email 2.54.0 Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: HE WEI (ギカク) carl9170_cmd_callback() copies a command response coming from the USB device into ar->readbuf using the device-reported length: memcpy(ar->readbuf, buffer + 4, len - 4); ar->readbuf points at the buffer supplied by the caller of carl9170_exec_cmd(), which is frequently an on-stack buffer sized to the expected response length (ar->readlen). The preceding sanity check only emits a warning and schedules a restart when ar->readlen != len - 4; it does not stop processing, so the memcpy() still runs with the attacker-controlled length. A malicious or malfunctioning AR9170 USB device can therefore answer a pending command with an over-sized response and overflow ar->readbuf, as reported by syzbot: BUG: KASAN: stack-out-of-bounds Write in carl9170_handle_command_response The comment in that branch already documents the intended behaviour ("Do not complete. The command times out, and we get a stack trace from there."), but the return statement was missing. Return after carl9170_restart() so an over-/under-sized response is neither copied into ar->readbuf nor completed; carl9170_exec_cmd() then times out and clears readbuf in its error path. Reported-by: syzbot+5c1ca6ccaa1215781cac@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=5c1ca6ccaa1215781cac Fixes: a84fab3cbfdc ("carl9170: 802.11 rx/tx processing and usb backend") Signed-off-by: HE WEI (ギカク) --- drivers/net/wireless/ath/carl9170/rx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/wireless/ath/carl9170/rx.c b/drivers/net/wireless/ath/carl9170/rx.c --- a/drivers/net/wireless/ath/carl9170/rx.c +++ b/drivers/net/wireless/ath/carl9170/rx.c @@ -145,6 +145,7 @@ static void carl9170_cmd_callback(struct ar9170 *ar, u32 len, void *buffer) * and we get a stack trace from there. */ carl9170_restart(ar, CARL9170_RR_INVALID_RSP); + return; } spin_lock(&ar->cmd_lock); -- 2.43.0