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 DE507C433F5 for ; Tue, 18 Jan 2022 03:41:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344719AbiARDls (ORCPT ); Mon, 17 Jan 2022 22:41:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345277AbiARDEh (ORCPT ); Mon, 17 Jan 2022 22:04:37 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F877C0219FE; Mon, 17 Jan 2022 18:48:10 -0800 (PST) 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 345DDB811D6; Tue, 18 Jan 2022 02:48:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 27E50C36AE3; Tue, 18 Jan 2022 02:48:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1642474089; bh=1Dan8dXqoNzgwNf+GccsTIVQp+glgJ3SqFIhl/iSHJc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ExUiUA17FX3MDS6TszeZsNFE63JdlTRd6hFrwoxufq7eWkYWsoQ/YYbgXKG0ezWss ElzrohEQl/clOarKXHT0u3j2mBmhz4UMnsADkFun8z2rEQr5fnqit8+oa7hzR7HlUK v9pzV0tqIPL1MTALYsRqa6HuwaFdeoGR4IzjC3rJgxDTyRMHJXUgiSRVcBcQuRow/b Y7RlcXsinzMlBvL1jvBECD47M7cd7F4NaR9oDmjY+dm57WboKFL46C4e/IF51XOQ4w OpMl7iv+URYOQjauOSG8otTiECJ4B9m4VcUyYUNIAZki0czERYN0RPOOd3al2CbWBS xJDwAMziDBn0Q== 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 4.19 31/59] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Date: Mon, 17 Jan 2022 21:46:32 -0500 Message-Id: <20220118024701.1952911-31-sashal@kernel.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220118024701.1952911-1-sashal@kernel.org> References: <20220118024701.1952911-1-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-media@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 d4987fd05d05f..d91bd32bd1f04 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 8c56d4c37a525..3513b1a6fcee9 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