From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f174.google.com (mail-qk1-f174.google.com [209.85.222.174]) (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 737EB3C3C06 for ; Fri, 17 Jul 2026 11:03:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784286229; cv=none; b=Fmd/E07zj5po6VwhktyvBjCgpvVpqUg2KPxLtWbeopxqYm74qsY7BVqLv8Lnel6zFKj/u9cwBuWPaYKqP7SCZrNzKcU4FLJvInUrRv04E5AcyzbqUpgZ2DoxdOwo0iOCCO2muABVIM8THFhymd0kBeu/d6OHBIK6qhJUqGjFJ8k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784286229; c=relaxed/simple; bh=jA79gpOkviouKGGXfJkuzjbm7sgvQfwwpHf05WgGl18=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=dO/Kx++oNgH+C/wIV/rOX/8yETO0JCNZQcNmypFJAJaCVq08SeQNMuCyiRKDeZa31aGzEZN2Mk0sUtSwed7gFpawGO3aazObWFam3nj9axLYPgWUUZ09cNEi0QnUYkLbR2TVFoRk4KigZG57bWkF0Lr32uCLCEv+0zXSRkAFK7M= 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=nakYVP1/; arc=none smtp.client-ip=209.85.222.174 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="nakYVP1/" Received: by mail-qk1-f174.google.com with SMTP id af79cd13be357-92e54f8c051so570337585a.3 for ; Fri, 17 Jul 2026 04:03:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1784286225; x=1784891025; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to:content-type; bh=pJUH2+9UwKuoF8Z5sAeBhPd3xy/csT/L8ZRS5KSSWKw=; b=nakYVP1/U/lgDxRh8JSSbnhxgiKjpV+p7U5vb+K7bdoTTQqalJWNIlER3qnU7Q8nkt QRNRG5HEE2f/NDopB/Usatyaj9AbEPx0D62A5TjHBm++HpQph4RkZVOMrNqXEXstsaQp nE48xYF4DKZZDoi2w5pP91SAAy1XnE2qPk6clxd0J0TT31bEd7XA2tblX3HYho3n1x2D 8ODV+V1o9Esj7uBznVsVem6+towFUnPF1/fYTWmMSY83jurLrotf9SDQJUBGAYv0OHvi P9hgpVyRgxemNoq71k4ea7/8TRvp0bFIFs2PGge12fW4vHtLxJxgoWQzTHQm7sgaZa1+ 49AQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784286225; x=1784891025; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to:content-type; bh=pJUH2+9UwKuoF8Z5sAeBhPd3xy/csT/L8ZRS5KSSWKw=; b=HYW/vvZp5R2xc743qqEh4usoy05bHBK6Ml6evm6LKVCJ1VXGh7SwrQCDkRcv4kYiWF 3PpRaMJ0HqfrxQQMy9UcG4CylQJFsZ1LYWgeaL+3auLiNH1ynMFki8Vk2PoFTVFpszDf YjkosPFuIuh0J2IkwUCudeRPgAGzrj8516nCDOgLn0OJ3mSH40zjNT/Y4NIDVo20roKK m1QAjC2scHv9PEnQh9L/Kkto0E2msZc2u4/ju6XSPpVvOHV9eDBojyW20PaEc2fjDVuC gUGcG3KqgIv6qjJyPrpxPxYFNHYn+EiItge7QG/iH7prN3Weus9OQuneSMp/IK2uHg65 IqQQ== X-Forwarded-Encrypted: i=1; AHgh+Rp6V2H0m9BHnmGy0AbOVxNGWHPolawbsvoX70mzaN3MwZ4lNDzV4swHJHdg2ByFdNKcsN9Iw0AR6QM9BZ48Qw==@vger.kernel.org X-Gm-Message-State: AOJu0YxZQvRCEY6Db43+MJGq/QXba1oK/0sni68orBm47q85wltwNtXf 8w3b2tFlZe+USXHAcnigkkmViLrGDlshPx4ChD99uyE0hXABICt9pA49 X-Gm-Gg: AfdE7clxt2n9kc4Bl6lC9eJ72R+jPXe2BzHN5EO5iFwzyerUKl80V8sgPrF11gfFa0r s468ZiDRey63eCezHYA6+MjWjNi/HiDitSLWiKiOPOsIcFa6YoIPPrJ1wyvGpMkhrt4QTV4H8oj 6wzg9vOUk0T/Y/gg9erFG5oeWn5Q5ujgUVzGhLyyHcN38LuscEfnofUDEGu/PKJJ4kqRR3yO/lh +7uUokPk2EVYhjFJEpDT2+hSZDaHktk0D48vDzAPXdbH2UxH3FJlkCcwRIV67/5Tacr6KK1n0la wj7HNBJb8bwFMYtWXrKFvjlBb7VegOE/JwbK24Rl8h267hsYJuF1djp+nQWVYoQDucA10QbSEHS Ry4XmojGlW9afAkZqhJSOkOgm8G6EIiA3dj1PxeS7lDaUPrjZO6OJZzcWsye3JkxlL+MQOZD99A HRs44GlxIZJ94b89Y+GSQhZ/V6V3pxmN2qRrRKLwcZ X-Received: by 2002:a05:620a:4147:b0:92e:6a43:4768 with SMTP id af79cd13be357-930b3e4e844mr224517685a.11.1784286224683; Fri, 17 Jul 2026 04:03:44 -0700 (PDT) Received: from mango-teamkim.. ([129.170.196.108]) by smtp.gmail.com with ESMTPSA id af79cd13be357-930b542d61dsm124744185a.24.2026.07.17.04.03.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 17 Jul 2026 04:03:44 -0700 (PDT) From: pip-izony To: Jeff Johnson , Kees Cook Cc: Seungjin Bae , Kyungtae Kim , Pontus Fuchs , "John W . Linville" , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] wifi: ar5523: validate rxlen against descriptor size and usblen in ar5523_data_rx_cb() Date: Fri, 17 Jul 2026 07:02:21 -0400 Message-ID: <20260717110219.2392132-3-eeodqql09@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <7bd71d11-d6f2-473d-b5ae-f5fbc972ef40@oss.qualcomm.com> References: <7bd71d11-d6f2-473d-b5ae-f5fbc972ef40@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Seungjin Bae In ar5523_data_rx_cb(), the `rxlen` variable is derived from desc->len, which is provided by the USB device. The function checks for an upper bound (rxlen > ar->rxbufsz) and for a zero value (!rxlen), but it fails to check for a proper lower bound against the size of the descriptor. If a malicious device provides an `rxlen` value that is positive but smaller than sizeof(struct ar5523_rx_desc), the subtraction in the call to skb_put() will result in an integer underflow. This passes a very large unsigned value to skb_put(), which then triggers a kernel panic upon detecting the potential buffer overflow. Fix this by adding a check to ensure `rxlen` is at least sizeof(struct ar5523_rx_desc) before performing the subtraction. Additionally, `rxlen` is not cross-checked against usblen (the number of bytes actually received). Since the frame layout is [ar5523_chunk][802.11 payload][ar5523_rx_desc] and `usblen` covers the whole buffer, a valid rxlen cannot exceed `usblen - sizeof(chunk)`. A device reporting a larger `rxlen` would cause skb_put() to expose descriptor trailer bytes or uninitialized skb tail data as 802.11 payload to ieee80211_rx_irqsafe(). Add a check to reject such frames. Fixes: b7d572e1871df ("ar5523: Add new driver") Suggested-by: Jeff Johnson Signed-off-by: Seungjin Bae --- v1 -> v2: cross-check rxlen against usblen to prevent overreading past the received payload drivers/net/wireless/ath/ar5523/ar5523.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/net/wireless/ath/ar5523/ar5523.c b/drivers/net/wireless/ath/ar5523/ar5523.c index 66ac396858a5..3ee4b020f416 100644 --- a/drivers/net/wireless/ath/ar5523/ar5523.c +++ b/drivers/net/wireless/ath/ar5523/ar5523.c @@ -589,6 +589,18 @@ static void ar5523_data_rx_cb(struct urb *urb) goto skip; } + if (rxlen < sizeof(struct ar5523_rx_desc)) { + ar5523_dbg(ar, "RX: Bad descriptor (len=%u is too small)\n", + rxlen); + goto skip; + } + + if (rxlen > usblen - sizeof(struct ar5523_chunk)) { + ar5523_dbg(ar, "RX: rxlen too large (rxlen=%u usblen=%d)\n", + rxlen, usblen); + goto skip; + } + skb_reserve(data->skb, sizeof(*chunk)); skb_put(data->skb, rxlen - sizeof(struct ar5523_rx_desc)); -- 2.43.0