From mboxrd@z Thu Jan 1 00:00:00 1970 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 34A5CC7EE29 for ; Thu, 25 May 2023 18:58:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243587AbjEYS6g (ORCPT ); Thu, 25 May 2023 14:58:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45096 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243568AbjEYSzf (ORCPT ); Thu, 25 May 2023 14:55:35 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0C6649ED; Thu, 25 May 2023 11:47:28 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D0AC360F92; Thu, 25 May 2023 18:45:29 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79B5DC433EF; Thu, 25 May 2023 18:45:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685040329; bh=k9tHMD1JfXB6FZDsje79FwzK4Ljazuakd2wCOOi5Wj4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NzmhRTwBiUUdGHwgdIURyxl5xrufT2FU/z90c199ZP/DVUFEXgy6RJQWavN6RlDT5 19capQAmdOHX2ecaVmuoyN+Pw1zD80WvfJz1mKF4nV7PreaeberD4aSjaKo92KcVJ5 DQXl8ufwxXOVjnaaGDFB8i8cGwxwGYEnW4NulmqoidFh8Erx77nKA5nn+K6tS2Ts4S RndCCLC1w6+JaE+rVYtHYNbYrfWoiOBm6Ok3bndUhVvl/7HKd7DsZ44QL/ljY8VVqv 8P6qo8DxrJIm0dQv2d2J+5XG1YIIdIhElShr8Qcih8JXw0nm/+FL7yXBVNu7ml36A1 cvXYtLHirYAtA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Wei Chen , Mauro Carvalho Chehab , Sasha Levin , zhongbaisong@huawei.com, linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 03/20] media: dvb-usb: az6027: fix three null-ptr-deref in az6027_i2c_xfer() Date: Thu, 25 May 2023 14:44:59 -0400 Message-Id: <20230525184520.2004878-3-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230525184520.2004878-1-sashal@kernel.org> References: <20230525184520.2004878-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wei Chen [ Upstream commit 858e97d7956d17a2cb56a9413468704a4d5abfe1 ] In az6027_i2c_xfer, msg is controlled by user. When msg[i].buf is null, commit 0ed554fd769a ("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()") fix the null-ptr-deref bug when msg[i].addr is 0x99. However, null-ptr-deref also happens when msg[i].addr is 0xd0 and 0xc0. We add check on msg[i].len to prevent null-ptr-deref. Link: https://lore.kernel.org/linux-media/20230310165604.3093483-1-harperchen1110@gmail.com Signed-off-by: Wei Chen Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/usb/dvb-usb/az6027.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/media/usb/dvb-usb/az6027.c b/drivers/media/usb/dvb-usb/az6027.c index f2b5ba1d28098..05988c5ce63ca 100644 --- a/drivers/media/usb/dvb-usb/az6027.c +++ b/drivers/media/usb/dvb-usb/az6027.c @@ -991,6 +991,10 @@ static int az6027_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int n /* write/read request */ if (i + 1 < num && (msg[i + 1].flags & I2C_M_RD)) { req = 0xB9; + if (msg[i].len < 1) { + i = -EOPNOTSUPP; + break; + } index = (((msg[i].buf[0] << 8) & 0xff00) | (msg[i].buf[1] & 0x00ff)); value = msg[i].addr + (msg[i].len << 8); length = msg[i + 1].len + 6; @@ -1004,6 +1008,10 @@ static int az6027_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int n /* demod 16bit addr */ req = 0xBD; + if (msg[i].len < 1) { + i = -EOPNOTSUPP; + break; + } index = (((msg[i].buf[0] << 8) & 0xff00) | (msg[i].buf[1] & 0x00ff)); value = msg[i].addr + (2 << 8); length = msg[i].len - 2; @@ -1029,6 +1037,10 @@ static int az6027_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int n } else { req = 0xBD; + if (msg[i].len < 1) { + i = -EOPNOTSUPP; + break; + } index = msg[i].buf[0] & 0x00FF; value = msg[i].addr + (1 << 8); length = msg[i].len - 1; -- 2.39.2