From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933806AbdKGAWf (ORCPT ); Mon, 6 Nov 2017 19:22:35 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:53831 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933783AbdKGAWb (ORCPT ); Mon, 6 Nov 2017 19:22:31 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mauro Carvalho Chehab" , "Prabhakar Lad" , "Hans Verkuil" Date: Mon, 06 Nov 2017 23:03:02 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 065/294] media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.50-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Prabhakar Lad commit da05d52d2f0f6bd61094a0cd045fed94bf7d673a upstream. this patch makes sure VPFE_CMD_S_CCDC_RAW_PARAMS ioctl no longer works for vpfe_capture driver with a minimal patch suitable for backporting. - This ioctl was never in public api and was only defined in kernel header. - The function set_params constantly mixes up pointers and phys_addr_t numbers. - This is part of a 'VPFE_CMD_S_CCDC_RAW_PARAMS' ioctl command that is described as an 'experimental ioctl that will change in future kernels'. - The code to allocate the table never gets called after we copy_from_user the user input over the kernel settings, and then compare them for inequality. - We then go on to use an address provided by user space as both the __user pointer for input and pass it through phys_to_virt to come up with a kernel pointer to copy the data to. This looks like a trivially exploitable root hole. Due to these reasons we make sure this ioctl now returns -EINVAL and backport this patch as far as possible. Fixes: 5f15fbb68fd7 ("V4L/DVB (12251): v4l: dm644x ccdc module for vpfe capture driver") Signed-off-by: Lad, Prabhakar Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Ben Hutchings --- drivers/media/platform/davinci/vpfe_capture.c | 22 ++-------------------- 1 file changed, 2 insertions(+), 20 deletions(-) --- a/drivers/media/platform/davinci/vpfe_capture.c +++ b/drivers/media/platform/davinci/vpfe_capture.c @@ -1708,27 +1708,9 @@ static long vpfe_param_handler(struct fi switch (cmd) { case VPFE_CMD_S_CCDC_RAW_PARAMS: + ret = -EINVAL; v4l2_warn(&vpfe_dev->v4l2_dev, - "VPFE_CMD_S_CCDC_RAW_PARAMS: experimental ioctl\n"); - if (ccdc_dev->hw_ops.set_params) { - ret = ccdc_dev->hw_ops.set_params(param); - if (ret) { - v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, - "Error setting parameters in CCDC\n"); - goto unlock_out; - } - ret = vpfe_get_ccdc_image_format(vpfe_dev, - &vpfe_dev->fmt); - if (ret < 0) { - v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, - "Invalid image format at CCDC\n"); - goto unlock_out; - } - } else { - ret = -EINVAL; - v4l2_dbg(1, debug, &vpfe_dev->v4l2_dev, - "VPFE_CMD_S_CCDC_RAW_PARAMS not supported\n"); - } + "VPFE_CMD_S_CCDC_RAW_PARAMS not supported\n"); break; default: ret = -ENOTTY;