From nobody Wed Feb 11 17:15:20 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76625C61DA4 for ; Mon, 13 Mar 2023 09:28:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229836AbjCMJ2D (ORCPT ); Mon, 13 Mar 2023 05:28:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229771AbjCMJ17 (ORCPT ); Mon, 13 Mar 2023 05:27:59 -0400 Received: from mail-pj1-x1036.google.com (mail-pj1-x1036.google.com [IPv6:2607:f8b0:4864:20::1036]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A16123A9B; Mon, 13 Mar 2023 02:27:57 -0700 (PDT) Received: by mail-pj1-x1036.google.com with SMTP id y15-20020a17090aa40f00b00237ad8ee3a0so11015180pjp.2; Mon, 13 Mar 2023 02:27:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1678699677; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=OpwxskmBPy4CpjtWMo+T8QeWJJwqkVX8aJFIYDNm7xs=; b=RAH/DVxOyUQvf/lt8KhbMbh/+OZthHAeg/X+tupO2oO4eZDpHXTABqSqSpe6TZjNs5 uzqROM+3NNEUCEZFZRlBeHuHLW09LzNS/jN35i4LpvEBqZN/LUDu91+iiIjcOJu5N/bZ z40CUczzdpdEbx+raY+hHQmiUwV06B1LZdgMIpSLwPEMJeEsgFqzHZZbH1Y77R5EfaPp T4gt/U+WyuUJ634o911ijRj66W4uKMdkU7V2oCmmt43MFsJ8Hs3aJ1AJUmByTP9JDhcU Nf15bNCSquSZ+GDN6ysVBEyhP7q0m5ShZ6/OAg/bo3WHsUboTsXXcRSPfgEhddzkSkgn 2RGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678699677; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=OpwxskmBPy4CpjtWMo+T8QeWJJwqkVX8aJFIYDNm7xs=; b=HJ3OUnjqpkeWuvLkXcdkmbG9l9rBeKjGN7EMmxmZrUoWkeYNqVBkDY/R8Sy6cgj9CO s1YdB1Ex426UVgHhKLBTjdDwDcJrtJdx4nlLZ6OgTcJpXM6LUUe8izYB33CSVs55KY3Y fFFhQv5rh825A6DjQ8OoWFjrNd8JmqxA/85b6U44cq3XajfX4uXUnEFIn/NMNsEvGE8t dYH+YQFfVAyG7ulrjD5Y+tVD/1zfnxC0qxZ2omxGjwrTqI4BTtr2nRv+rOE5RmWdrD5S qwuw1k92NsO748VvtI2XVpcmnufIPgbaRivJ6doZChmZfx+MuXMCxqBlpsmPVYWLDfgZ hcKg== X-Gm-Message-State: AO0yUKXAT3HD1QkmWOGYe6580uSUufCpSundRLOgJfVwTLPYnweeHSce xjw1cmnTq8bThQ9ImVQ1j+Q= X-Google-Smtp-Source: AK7set9S4EYlxcmQI8BkTNR8foIisBUh7fq7Feg2Vp+nL4Aa+KNIQ79f+FRfLcaXlypfLn0lyfkxKA== X-Received: by 2002:a17:90b:38cc:b0:237:bf05:40b with SMTP id nn12-20020a17090b38cc00b00237bf05040bmr36653252pjb.20.1678699677129; Mon, 13 Mar 2023 02:27:57 -0700 (PDT) Received: from chcpu13.cse.ust.hk (191host119.mobilenet.cse.ust.hk. [143.89.191.119]) by smtp.gmail.com with ESMTPSA id a13-20020a17090aa50d00b00230dc295651sm956751pjq.8.2023.03.13.02.27.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Mar 2023 02:27:56 -0700 (PDT) From: Wei Chen To: crope@iki.fi Cc: mchehab@kernel.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Wei Chen Subject: [PATCH] media: dvb-usb-v2: ce6230: Fix null-ptr-deref in ce6230_i2c_master_xfer() Date: Mon, 13 Mar 2023 09:27:51 +0000 Message-Id: <20230313092751.209496-1-harperchen1110@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" In ce6230_i2c_master_xfer, msg is controlled by user. When msg[i].buf is null and msg[i].len is zero, former checks on msg[i].buf would be passed. Malicious data finally reach ce6230_i2c_master_xfer. If accessing msg[i].buf[0] without sanity check, null ptr deref would happen. We add check on msg[i].len to prevent crash. Similar commit: commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_= i2c_xfer()") Signed-off-by: Wei Chen --- drivers/media/usb/dvb-usb-v2/ce6230.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/media/usb/dvb-usb-v2/ce6230.c b/drivers/media/usb/dvb-= usb-v2/ce6230.c index 44540de1a206..d3b5cb4a24da 100644 --- a/drivers/media/usb/dvb-usb-v2/ce6230.c +++ b/drivers/media/usb/dvb-usb-v2/ce6230.c @@ -101,6 +101,10 @@ static int ce6230_i2c_master_xfer(struct i2c_adapter *= adap, if (num > i + 1 && (msg[i+1].flags & I2C_M_RD)) { if (msg[i].addr =3D=3D ce6230_zl10353_config.demod_address) { + if (msg[i].len < 1) { + i =3D -EOPNOTSUPP; + break; + } req.cmd =3D DEMOD_READ; req.value =3D msg[i].addr >> 1; req.index =3D msg[i].buf[0]; @@ -117,6 +121,10 @@ static int ce6230_i2c_master_xfer(struct i2c_adapter *= adap, } else { if (msg[i].addr =3D=3D ce6230_zl10353_config.demod_address) { + if (msg[i].len < 1) { + i =3D -EOPNOTSUPP; + break; + } req.cmd =3D DEMOD_WRITE; req.value =3D msg[i].addr >> 1; req.index =3D msg[i].buf[0]; --=20 2.25.1