From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-vk1-f177.google.com (mail-vk1-f177.google.com [209.85.221.177]) (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 7471634F48F for ; Fri, 17 Apr 2026 03:03:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776394991; cv=none; b=H+TXEY0VOMwXhLC2gk27tiD0Hy+M7uQhKyQ/n0dItpt8tpxoWXkS0M39uZ2GEV6sPSw91mcRw77P1547AgLqlNXq0wEHZOwDaNoOGLeQwZZ7geXoyGRUlNtwOsLYPlWugCUPeWhbP36spdnzC9ZqBxgAwSFM/Mgebru0Zng9AEY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776394991; c=relaxed/simple; bh=Qf2pj9mdWhoOhQaMbpBXpuYL+EpLLGiJqu1COixk28I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=O9Rd8/dO2KAOM1EkNQfIKNqKe0/v+aGKItU+ovB8ZAMgcGdXOacwL58R9K+jqlLe9k0X0HR/o1hax3r3LtF9gi4HEVki1Mm4MSdDenI3bizMdtrRK0lAy3MhOqA2y2o5tOPshukGAjOX3z5GKB66D8JOFLYtg3CUmKx77Q25hlA= 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=YLS8gYon; arc=none smtp.client-ip=209.85.221.177 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="YLS8gYon" Received: by mail-vk1-f177.google.com with SMTP id 71dfb90a1353d-56adf76631cso78646e0c.1 for ; Thu, 16 Apr 2026 20:03:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1776394987; x=1776999787; 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=Rovnln3bQexjtYGlnIDtq4x3huEk7/gghBgaMQ2B6FQ=; b=YLS8gYonNFxa/gf2Z7h+fPWpE2PEuXBZAm6gfa6RnkjCYcXkmwQqQDLPkHRQF/qz2Y /bYaIFNCcKb2Rqzkkmf93APSiWxNiUmBY/BasnHK11eircb6Eh+tS9j+VWQ5+/7wZtlz Rp5A7TionvvBLMA7enQBERC9RpYMCTWlnl5LKRBnqwuzqXSwbLswxOrsthDrrV5VvMVZ H/ogmEW98AAEpedQ5W4bP289gL6hWwfsiumSoLEE0mxxpW0m7mQ+jRBZtFFzrSmh+NUC Z+h75cfNc0X3C263g3wSLa8Lbxzsvnsg/qswFJrSk7E3aJIyf6hw80cLMMZtkRKsq6ST QbLg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776394987; x=1776999787; 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=Rovnln3bQexjtYGlnIDtq4x3huEk7/gghBgaMQ2B6FQ=; b=LVGbAslkQNThFzQwQ0fY5VhMvBFnzUd7nLKg38Muy5wVgHs2+a0zEcsOCf2RlVdqUb oIl8hHKcMNDkGuaIepOAqS3jvkLh3jRX/WGATrgv93JhuVLNbWRmGJcnuM8cJ/0gtUYA uERaWlWIB+QzQgS+ZoyOYE86gww30L96juZgyAqW9qgo4vG5/fVan7hh9DpgYhZJ+g/2 QpOkLVeh/8h0hCWyeBn7EcP4yIfrWcaLoaxCrq8YnOxVkIXX+KF16npdKDHdiQ+sFTxc acNui3Yf++XXmUsWd/6Ap2RbCDzbPkFXjcGn627M8GKaTDWScG5FDtw5zuLkKETaD7Jd 7vHw== X-Forwarded-Encrypted: i=1; AFNElJ9tWnehbbP+jDjW9LxpQTWaburgmS03Eq9LKMMqHKzfhQcK7BhkHZObD6RqykjABa0brvx7MM2on17GvpQ=@vger.kernel.org X-Gm-Message-State: AOJu0YzucfPONyQJNNAH/j4UXbkyva+wUj6RSqHY1Wu9u0Jv1EcZCzKG kzdAZoXKPAu6HooW2j0rkFxUEmbherbls/4VbKVcRm+vbq098bBsY/g4 X-Gm-Gg: AeBDievXw/dHUnzSGRQ2K6yZvZwGDLzWN4JMXT+lt56XCbxrkB43jRCOX6n+NKfjfaC d/7i8hghm61hFDwzvJmKaQrQ072mDBc4xSPSm7uT7qAxi464VfmU8IJIawN7hqTlv2971TUk5AO A/NPB8fJUg6yXp13DCUEpaQtipb6fu+m0+tJwSSpsUwBhn4WODuPPkr0mgxvU+6E/I2nqo3EH6p CtCg20zj2M999qtU+OrbTYA7OeELhyESYvOeDhBKkBTTjV3FWaSFcqkIUqSzFDLIuhNRunhS+Ky HGmrGtEHvw3Sugt4IdYqYpJblwzF7ug+ZSPqCsu3ec1pWt5YLfY58YHluTR0LElPycPL3GIsTes Actv/fcYsGIy8VkeIlP/W5BhUFvurCbDT5x9x7XP+JxBML257S36LDrOFrgcu2vnBTITCGQDQyj WfjrTBo5SgRdu984iQkyC0YzCdDVgdsKidCiHYmnnGfwmVfN/wR9Tb X-Received: by 2002:a05:6123:10b:b0:56d:b4d1:3c3a with SMTP id 71dfb90a1353d-56fa55c512amr711056e0c.0.1776394986916; Thu, 16 Apr 2026 20:03:06 -0700 (PDT) Received: from localhost.localdomain ([102.244.98.124]) by smtp.gmail.com with ESMTPSA id 71dfb90a1353d-56fa93275f4sm131275e0c.13.2026.04.16.20.03.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Apr 2026 20:03:06 -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 v5 5/5] staging: rtl8723bs: fix negative length in WEP decryption Date: Fri, 17 Apr 2026 04:01:10 +0100 Message-ID: <20260417030110.42991-6-delenetchior1@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260417030110.42991-1-delenetchior1@gmail.com> References: <20260417030110.42991-1-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 --- 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