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 5C001C4332F for ; Tue, 18 Jan 2022 03:02:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352776AbiARDAh (ORCPT ); Mon, 17 Jan 2022 22:00:37 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:44364 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349849AbiARCuc (ORCPT ); Mon, 17 Jan 2022 21:50:32 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 5D190612CC; Tue, 18 Jan 2022 02:50:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E9A24C36AE3; Tue, 18 Jan 2022 02:50:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642474231; bh=iMVmUcIEnhx1/dyD/Ep+9ykJlQn0RTzeVgSkysfS/jI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b/8jO2KJqmBGXJDpAKvTLdeFMSLUPyBkoPTUMErXAuRuhtqLzvOyhyP0abukqz0+M rHzEUAHlqjM1SeTumz+AxEm70AUk4ynPfJD3+dYAhdMfL9Mt/eZnOQwWwJMjTh8g8q /ITTaJL8FOM4IYE2qRPuzxxH+H7EaYPS/sVLcF98hGQAnBtNysQU5Omdq1CD8bzWi6 KyvmO3Wnp54lvpX8+VsOxhJ8/poI2ssu/MFtvNQA1Tl0dvL1OB310oVmWE6a307zxY Zv56gEaZrz10bic4w0Ndt7k28qR9Dq082ze043wrdW2/zH2zg78aD+0Yx7YVUOHjyi YkFNUa2gkjB2A== 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 4.14 34/56] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Date: Mon, 17 Jan 2022 21:48:46 -0500 Message-Id: <20220118024908.1953673-34-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024908.1953673-1-sashal@kernel.org> References: <20220118024908.1953673-1-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: stable@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 930d2c94d5d30..2c9365a39270a 100644 --- a/drivers/media/common/saa7146/saa7146_fops.c +++ b/drivers/media/common/saa7146/saa7146_fops.c @@ -524,7 +524,7 @@ 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 a527d86b93a77..7f498aebb4112 100644 --- a/drivers/media/pci/saa7146/hexium_gemini.c +++ b/drivers/media/pci/saa7146/hexium_gemini.c @@ -296,7 +296,12 @@ 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