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 A8F3BC433F5 for ; Mon, 24 Jan 2022 19:02:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S245410AbiAXTCS (ORCPT ); Mon, 24 Jan 2022 14:02:18 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:56420 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343909AbiAXS6h (ORCPT ); Mon, 24 Jan 2022 13:58:37 -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 EDC3EB8121D; Mon, 24 Jan 2022 18:58:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20B00C340E5; Mon, 24 Jan 2022 18:58:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643050714; bh=0EuiXQC7yZLmB+/NRw14oLRHq8SrNpRc3adz04dxiF0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WKpAA2wfhOBvmpBB64WZ5L1pgH83j2KfyaV+1BXGpe8mgokG4W0jZTXQKAqH4i7Ce alwwWzPH86y9jHm3VjsA04902Ykxd3WLuMjy6J4oOeVyA1Ubb8njBhVNeGHzHwphKU VL5C16C4i3DMUIsbKYl9iT+AE9rnvTtDZtrAelHs= 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 4.9 090/157] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Date: Mon, 24 Jan 2022 19:43:00 +0100 Message-Id: <20220124183935.642741273@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124183932.787526760@linuxfoundation.org> References: <20220124183932.787526760@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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 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 be85a2c4318e7..be91a2de81dcc 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