From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-vs1-f50.google.com (mail-vs1-f50.google.com [209.85.217.50]) (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 23F7F36920F for ; Fri, 17 Apr 2026 06:12:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.217.50 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776406360; cv=none; b=V9r0ie4Ifuk7KYBcIFf/Uz0VBdJM5U/Yp9zBg+DnWEHlQFUxmlFzryjeUue+DrTaCkCkeIpeE+dRhzaMx6/6i5dio/GGlFM1BnrHj0n4jLz7ELTGeGiHRaSQTCOfL07kLGXOZViR2CY73WczdeI9DzrkSBwKjVGp7zVP0wTAwUM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776406360; c=relaxed/simple; bh=Mkn9VdUMU/TvZ8JqVerjm7KuO8HxezoafwaUYXwJEtE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=FmmBlzGtCK0xf9a/cmBxLOEOA86wdQed9TJ2VaCWZD4oSMMtDB6qcJ5p3qv8RupZpJZJJ4H6VRtQK4CwiWog3hGCtHTE0+hiOevhIhLdwNol5c9Mm0BjgEqJ9f9OkZQbTb1MEZn2qjlFfSjufcQES+lAyS+JXla2UAfcYBf22II= 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=sPoEolU6; arc=none smtp.client-ip=209.85.217.50 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="sPoEolU6" Received: by mail-vs1-f50.google.com with SMTP id ada2fe7eead31-610aadb2d9fso84216137.0 for ; Thu, 16 Apr 2026 23:12:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1776406358; x=1777011158; 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; bh=chi0rjV8j6xNxAz/qcwmHJNYbKqeX24uRogPLx+nbHQ=; b=sPoEolU6BuGWGmhU+V04B2Ir8TG6k1/TqAYP4ENAflbuDjym/NM8KspYD2ZkrPBXeJ kGujltRbmj/gSaFaTN3wh63FwLr0ZfvCKRujLR5X71O1nmVWfc+nV7cRPtAp395xNdFp YSVcYokYyFlzDH7izxvO+4S2twu0lIglTrOZcKkN3g2KwCR7vANRK4Dqqm6cJxzjTSzD ne78wSKFK9SHNPOaneTU/VYevEVtGPWPqp3a7PbCnmeSPxMQMWx8ItxpVjE5X+E1LWOh yw74YEEPK9eY2qq3GW4N10Yez6vl9zwe4z8rW/9vj2UXdIFhzDsegp9WZF44qM9fO/iL frRg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776406358; x=1777011158; 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; bh=chi0rjV8j6xNxAz/qcwmHJNYbKqeX24uRogPLx+nbHQ=; b=tXza7+GZF8hVosBNP+befFuE3mpC/7oS+N2AR82p/DT0KPGmu9Xzeaok7qE+QpPnAG afVTFIhKD0bod2HANXXUvJOUm5cpKkFcN/aCXRjqRqj4P20YZZa+U4B1Hz2qQEU884vx v0uGBMB9jKsfiWPXo4KwRbQ3jqzZACSWEWs8DyKB0sbZazOjGvDsQ/Ea878L6NpDwgLR S3D/10nK6B45RYGyrtlJcz+CxaJfMXkK1/hFt2YH0GgoPSc/oT2buCYrxIDioWJUfYFh /YbnTVIHz1luezIzpzQ3HwMaoiI+BB96ZgWh2EFEpZqRQ0DpDVJJHLhXh5D+yTX6NgKi Yegw== X-Forwarded-Encrypted: i=1; AFNElJ8PovVC2xYGeiFSit7PgqwWQx4a06HAAhw0eyzh386etpipqcqNRj2dgcLf8hRbfUQXheuNTmrCGyNzrSw=@vger.kernel.org X-Gm-Message-State: AOJu0YyCfS9rNjwfMaQ5cBuHv/+YHMDK2ehdc/T0dP/Ilup/KsQPI+hO wNW5owJDJiVkMOYpR36CiIqXOTIQ5xqYsmwbpZnybK0C/EtlJseVw6H9 X-Gm-Gg: AeBDieszp6A8AJaK80mkPTtC0UY9CS1IJLRdm5Ys9L3A99REhMuq0Yuzz5zA3VqZyiJ TbSscIXTGfZvP68RcJLsPKQYUuw48mRh7vvpWSl3QL/k62ve8b1rGk8E7BL87+OGy96lOLUfGmo 3gf244sasIjMjyl1UWKKWs31LOy8nDh0Aikx1UOaFkUz6a4Hi5PBn/ig/NTrSVia7RJMvvh2fy+ 5e+JYbh8YyG80dJaX/Ipfz9fdp920Tku0jiKvIFpqAys8sED+0zBUBZ5h9fJRQXkHlR32Nwe3we d+warAJz/L+smAWG+Feh007Iod2eQDBWFgpdpG798NmkHv8Yvy8OKh33XB5eNJFPUJq8Rwqh+IT F9ySgfiJ86BhnUdyU7iueRVJswVEWYtaNtUESaHHOF9jkNxAnABmvNuNi+PpzVVwHsi2lbeXmoa NFHMpQp9+wLjCR0cJEDVIBQfsm4NWpsemYH87ZEYXbowxxhz+WLfWfY/iuvnfHqio= X-Received: by 2002:a05:6102:5122:b0:608:759a:53bc with SMTP id ada2fe7eead31-616f1c595b4mr526551137.0.1776406358162; Thu, 16 Apr 2026 23:12:38 -0700 (PDT) Received: from localhost.localdomain ([102.244.98.124]) by smtp.gmail.com with ESMTPSA id a1e0cc1a2514c-9589093a8bbsm297947241.3.2026.04.16.23.12.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Apr 2026 23:12:37 -0700 (PDT) From: Delene Tchio Romuald To: gregkh@linuxfoundation.org Cc: error27@gmail.com, luka.gejak@linux.dev, hansg@kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, stable@vger.kernel.org, Delene Tchio Romuald Subject: [PATCH v6 5/5] staging: rtl8723bs: fix negative length in WEP decryption Date: Fri, 17 Apr 2026 07:10:48 +0100 Message-ID: <20260417061048.62484-6-delenetchior1@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260417061048.62484-1-delenetchior1@gmail.com> References: <20260417061048.62484-1-delenetchior1@gmail.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit In rtw_wep_decrypt(), the payload length is computed as: length = frame->len - prxattrib->hdrlen - prxattrib->iv_len; All operands are unsigned. If the frame is shorter than the sum of the header length, IV length and the 4-byte ICV, this subtraction wraps around or produces a value smaller than 4; the subsequent crc32_le(~0, payload, length - 4) call then wraps length - 4 to a huge value and reads past the end of the receive buffer. An attacker within WiFi radio range can exploit this by sending a crafted short WEP-encrypted frame. No authentication is required. Validate that the frame is large enough to contain at least the 4-byte ICV on top of the header and IV before computing length. Found by reviewing length arithmetic in the WEP decrypt path. Not tested on hardware. Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver") Cc: stable@vger.kernel.org Signed-off-by: Delene Tchio Romuald --- v6: unchanged. v5: tighten the length check to also cover the 4-byte ICV so that the subsequent crc32_le(payload, length - 4) call cannot underflow length - 4. v4: add Fixes: tag and Cc: stable (Dan Carpenter). v3: rebased on staging-next; sent as numbered series with proper Cc from get_maintainer.pl. v2: rebased on staging-next (v1 was based on v7.0-rc6 and did not apply). drivers/staging/rtl8723bs/core/rtw_security.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/staging/rtl8723bs/core/rtw_security.c b/drivers/staging/rtl8723bs/core/rtw_security.c index a00504ff29109..ddd6ed2245035 100644 --- a/drivers/staging/rtl8723bs/core/rtw_security.c +++ b/drivers/staging/rtl8723bs/core/rtw_security.c @@ -113,6 +113,12 @@ void rtw_wep_decrypt(struct adapter *padapter, u8 *precvframe) memcpy(&wepkey[0], iv, 3); /* memcpy(&wepkey[3], &psecuritypriv->dot11DefKey[psecuritypriv->dot11PrivacyKeyIndex].skey[0], keylength); */ memcpy(&wepkey[3], &psecuritypriv->dot11DefKey[keyindex].skey[0], keylength); + + /* Ensure the frame is long enough for WEP payload and ICV */ + if (((union recv_frame *)precvframe)->u.hdr.len < + prxattrib->hdrlen + prxattrib->iv_len + 4) + return; + length = ((union recv_frame *)precvframe)->u.hdr.len - prxattrib->hdrlen - prxattrib->iv_len; payload = pframe + prxattrib->iv_len + prxattrib->hdrlen; -- 2.43.0