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 D611EC433FE for ; Tue, 18 Jan 2022 02:29:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343724AbiARC26 (ORCPT ); Mon, 17 Jan 2022 21:28:58 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:40180 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245190AbiARC0k (ORCPT ); Mon, 17 Jan 2022 21:26:40 -0500 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 ams.source.kernel.org (Postfix) with ESMTPS id D9B6BB8122C; Tue, 18 Jan 2022 02:26:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD585C36AF3; Tue, 18 Jan 2022 02:26:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642472796; bh=zzwXETvO8DRgU0B6/KjTgVdtgOFdMCxyOYkTNdKrc3I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GFDNdYNWxHDIftakssdafl/jDHpam9qoldy3UyQ+zmlOcE8yJpYSEVO+y/mB6awS1 2fwBjE367iudgUBFfrj767ORmispNIEKJoKV3cbGmsq6E7K0Co+yWUuMpt2sqbNjNE eJzMexq29XgWy5g3OI9q4oVCzKEpr/HJzIYUnNuKHc1S3p/OHLdKnX39KEmwtWSQtZ f4Bu4CMZXbkH2fLRuY1k8hPfMK0qHOHUecW6W/ZTh7o4t0wF998NGKTbtTsHKFiU8H jz56wO5Y/uhwlvywejdEGVL8rcS/iXAR1jysKyxl/jtItXeF5NBsMPOQBg7CKShpBp 3JSPqpjaPopVA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Zhou Qingyang , Mauro Carvalho Chehab , Sasha Levin , hverkuil@xs4all.nl, mchehab@kernel.org, linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 5.16 136/217] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Date: Mon, 17 Jan 2022 21:18:19 -0500 Message-Id: <20220118021940.1942199-136-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118021940.1942199-1-sashal@kernel.org> References: <20220118021940.1942199-1-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: Zhou Qingyang [ Upstream commit 3af86b046933ba513d08399dba0d4d8b50d607d0 ] In hexium_attach(dev, info), saa7146_vv_init() is called to allocate a new memory for dev->vv_data. saa7146_vv_release() will be called on failure of saa7146_register_device(). There is a dereference of dev->vv_data in saa7146_vv_release(), which could lead to a NULL pointer dereference on failure of saa7146_vv_init(). Fix this bug by adding a check of saa7146_vv_init(). This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_VIDEO_HEXIUM_GEMINI=m show no new warnings, and our static analyzer no longer warns about this code. Link: https://lore.kernel.org/linux-media/20211203154030.111210-1-zhou1615@umn.edu Signed-off-by: Zhou Qingyang Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/common/saa7146/saa7146_fops.c | 2 +- drivers/media/pci/saa7146/hexium_gemini.c | 7 ++++++- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/media/common/saa7146/saa7146_fops.c b/drivers/media/common/saa7146/saa7146_fops.c index baf5772c52a96..be32159777142 100644 --- a/drivers/media/common/saa7146/saa7146_fops.c +++ b/drivers/media/common/saa7146/saa7146_fops.c @@ -521,7 +521,7 @@ int saa7146_vv_init(struct saa7146_dev* dev, struct saa7146_ext_vv *ext_vv) ERR("out of memory. aborting.\n"); kfree(vv); v4l2_ctrl_handler_free(hdl); - return -1; + return -ENOMEM; } saa7146_video_uops.init(dev,vv); diff --git a/drivers/media/pci/saa7146/hexium_gemini.c b/drivers/media/pci/saa7146/hexium_gemini.c index 2214c74bbbf15..3947701cd6c7e 100644 --- a/drivers/media/pci/saa7146/hexium_gemini.c +++ b/drivers/media/pci/saa7146/hexium_gemini.c @@ -284,7 +284,12 @@ static int hexium_attach(struct saa7146_dev *dev, struct saa7146_pci_extension_d hexium_set_input(hexium, 0); hexium->cur_input = 0; - saa7146_vv_init(dev, &vv_data); + ret = saa7146_vv_init(dev, &vv_data); + if (ret) { + i2c_del_adapter(&hexium->i2c_adapter); + kfree(hexium); + return ret; + } vv_data.vid_ops.vidioc_enum_input = vidioc_enum_input; vv_data.vid_ops.vidioc_g_input = vidioc_g_input; -- 2.34.1