From patchwork Mon Jan 24 18:42:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 535980 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 55BD1C433FE for ; Mon, 24 Jan 2022 20:01:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354008AbiAXUBp (ORCPT ); Mon, 24 Jan 2022 15:01:45 -0500 Received: from dfw.source.kernel.org ([139.178.84.217]:55680 "EHLO dfw.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1358273AbiAXT7V (ORCPT ); Mon, 24 Jan 2022 14:59:21 -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 995BA60B43; Mon, 24 Jan 2022 19:59:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 69E57C340E5; Mon, 24 Jan 2022 19:59:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643054359; bh=Mmov4kXM/0WU3bh6vK5IbxHSy3H97/BMQnWmsVg6fm0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LDhG/HCEdfzq1g5EX3iyT5513seI2/TyI8kg7XEwg/t6oJtYDpB1wcxLzEqRI9ZI0 /OICjauJmL5K8n/dmrHz7bGugg9X7VDM7Co/fmasvqOHE8qXLpDIaQljPP+kVSlcSQ eNfHVtiriLPMGS+XxwgjI5ZPs9DM8W9OJQ+64GkY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zhou Qingyang , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 5.10 364/563] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Date: Mon, 24 Jan 2022 19:42:09 +0100 Message-Id: <20220124184037.002398444@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184024.407936072@linuxfoundation.org> References: <20220124184024.407936072@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 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 d6531874faa65..8047e305f3d01 100644 --- a/drivers/media/common/saa7146/saa7146_fops.c +++ b/drivers/media/common/saa7146/saa7146_fops.c @@ -523,7 +523,7 @@ 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;