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 B2853EEB57A for ; Sat, 9 Sep 2023 00:44:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346086AbjIIAo0 (ORCPT ); Fri, 8 Sep 2023 20:44:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37528 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346240AbjIIAnn (ORCPT ); Fri, 8 Sep 2023 20:43:43 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B7EB42D78; Fri, 8 Sep 2023 17:41:13 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 77561C433CD; Sat, 9 Sep 2023 00:40:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1694220057; bh=Dr4kmbd/nBLjPEX7DVEU2QK+WQj2BZS5H87ZSAfXG/o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nh7NngvJi78APi6s49X5WeIm0nIiTlb0ATQWmdv1WAo7/5I4lK/WKNMvlfI+eTJgb ZpDDJfrjbXmO1bSk93Nono3t01YIJuiY2+sOxuGg7VuRY88bBcnQ3xPWPijNRPAlt3 Xx5c1hrxiTKzaWgIlrOiobVZJsofLqS8RfbLRtg9cgsqUPv7xtltKd/k8b6nBvZ90K 7xWEBWE+I7w4RtbmkW2t4ygeXW5+gOMG1hJxWAOC+S45JLNgg2ycvfC/NMKYqCzVc2 FWHQ0D5Pjh+nCiqLlSqFSSXnu9reIGmIKtPpnmihHfGmBGgg1fadjLkVGttK3WrEhE wreZVJjo0sq1g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zhang Shurong , Hans Verkuil , Sasha Levin , mchehab@kernel.org, linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 05/14] media: az6007: Fix null-ptr-deref in az6007_i2c_xfer() Date: Fri, 8 Sep 2023 20:40:36 -0400 Message-Id: <20230909004045.3581014-5-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230909004045.3581014-1-sashal@kernel.org> References: <20230909004045.3581014-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 4.19.294 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhang Shurong [ Upstream commit 1047f9343011f2cedc73c64829686206a7e9fc3f ] In az6007_i2c_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 az6007_i2c_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: Zhang Shurong Signed-off-by: Hans Verkuil Signed-off-by: Sasha Levin --- drivers/media/usb/dvb-usb-v2/az6007.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/media/usb/dvb-usb-v2/az6007.c b/drivers/media/usb/dvb-usb-v2/az6007.c index 8e914be5b7c5e..2f40eb6bdbb83 100644 --- a/drivers/media/usb/dvb-usb-v2/az6007.c +++ b/drivers/media/usb/dvb-usb-v2/az6007.c @@ -796,6 +796,10 @@ static int az6007_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], if (az6007_xfer_debug) printk(KERN_DEBUG "az6007: I2C W addr=0x%x len=%d\n", addr, msgs[i].len); + if (msgs[i].len < 1) { + ret = -EIO; + goto err; + } req = AZ6007_I2C_WR; index = msgs[i].buf[0]; value = addr | (1 << 8); @@ -810,6 +814,10 @@ static int az6007_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], if (az6007_xfer_debug) printk(KERN_DEBUG "az6007: I2C R addr=0x%x len=%d\n", addr, msgs[i].len); + if (msgs[i].len < 1) { + ret = -EIO; + goto err; + } req = AZ6007_I2C_RD; index = msgs[i].buf[0]; value = addr; -- 2.40.1