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 CE3EAC7EE29 for ; Thu, 25 May 2023 18:53:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243125AbjEYSxV (ORCPT ); Thu, 25 May 2023 14:53:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40062 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243295AbjEYSu3 (ORCPT ); Thu, 25 May 2023 14:50:29 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98A021FE0; Thu, 25 May 2023 11:43:52 -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 12C5A60BEC; Thu, 25 May 2023 18:42:53 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C01BFC433EF; Thu, 25 May 2023 18:42:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685040172; bh=9EQXT58RyG9prTO2BNkOjgI9uD1pv1HBbJFbYbB5CnI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DnreKnjeGuVsp0/xmVfUrRHcoKg4eZZe4FZlA/cSnJ6R0xAsZulNJaFvh8hMGRvXX +A5KdrU1uxItEnsIIiaINADi4fOoCYjIR5aV/kBjUqmGX0yV7c+Elr9Ny3Mu27UWRv EcNu/eHjsbt8zYBRf+KRKC/BHxYuAkCw5h/GHuyByg1TtjdHftLfXYovfNVjl/5lpI cqnRt7FRum2HDNVzXpXGStxNm5atsF/FERla9KpuViibWPqcUK4niGCzjJpUrInhuJ +bX5VceDsyykT8H85jopEoVZO62v7WqjjZAPnb8fDVR9OLEn2miwV7P7h2AgPUIhnR uBtQKM2Ej5zWw== 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 5.4 05/27] media: dvb-usb: az6027: fix three null-ptr-deref in az6027_i2c_xfer() Date: Thu, 25 May 2023 14:42:14 -0400 Message-Id: <20230525184238.1943072-5-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230525184238.1943072-1-sashal@kernel.org> References: <20230525184238.1943072-1-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 ffc0db67d4d68..2b56393d10008 100644 --- a/drivers/media/usb/dvb-usb/az6027.c +++ b/drivers/media/usb/dvb-usb/az6027.c @@ -988,6 +988,10 @@ 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; @@ -1001,6 +1005,10 @@ 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; @@ -1026,6 +1034,10 @@ 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