From patchwork Mon Jul 12 07:16:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 475701 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.0 required=3.0 tests=BAYES_00, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4092BC11F76 for ; Mon, 12 Jul 2021 07:19:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 29A846100B for ; Mon, 12 Jul 2021 07:19:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240830AbhGLHWS (ORCPT ); Mon, 12 Jul 2021 03:22:18 -0400 Received: from www.linuxtv.org ([130.149.80.248]:56978 "EHLO www.linuxtv.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344811AbhGLHUy (ORCPT ); Mon, 12 Jul 2021 03:20:54 -0400 Received: from mchehab by www.linuxtv.org with local (Exim 4.92) (envelope-from ) id 1m2qCa-003ihS-HQ; Mon, 12 Jul 2021 07:18:04 +0000 From: Mauro Carvalho Chehab Date: Mon, 12 Jul 2021 07:16:31 +0000 Subject: [git:media_stage/master] media: uvc: don't do DMA on stack To: linuxtv-commits@linuxtv.org Cc: Laurent Pinchart , stable@vger.kernel.org Mail-followup-to: linux-media@vger.kernel.org Forward-to: linux-media@vger.kernel.org Reply-to: linux-media@vger.kernel.org Message-Id: Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is an automatic generated email to let you know that the following patch were queued: Subject: media: uvc: don't do DMA on stack Author: Mauro Carvalho Chehab Date: Thu Jun 17 14:33:29 2021 +0200 As warned by smatch: drivers/media/usb/uvc/uvc_v4l2.c:911 uvc_ioctl_g_input() error: doing dma on the stack (&i) drivers/media/usb/uvc/uvc_v4l2.c:943 uvc_ioctl_s_input() error: doing dma on the stack (&i) those two functions call uvc_query_ctrl passing a pointer to a data at the DMA stack. those are used to send URBs via usb_control_msg(). Using DMA stack is not supported and should not work anymore on modern Linux versions. So, use a kmalloc'ed buffer. Cc: stable@vger.kernel.org # Kernel 4.9 and upper Reviewed-by: Laurent Pinchart Signed-off-by: Mauro Carvalho Chehab drivers/media/usb/uvc/uvc_v4l2.c | 34 +++++++++++++++++++++++----------- 1 file changed, 23 insertions(+), 11 deletions(-) diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c index 252136cc885c..6acb8013de08 100644 --- a/drivers/media/usb/uvc/uvc_v4l2.c +++ b/drivers/media/usb/uvc/uvc_v4l2.c @@ -899,8 +899,8 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input) { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + u8 *buf; int ret; - u8 i; if (chain->selector == NULL || (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) { @@ -908,22 +908,27 @@ static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input) return 0; } + buf = kmalloc(1, GFP_KERNEL); + if (!buf) + return -ENOMEM; + ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, chain->selector->id, chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, - &i, 1); - if (ret < 0) - return ret; + buf, 1); + if (!ret) + *input = *buf - 1; - *input = i - 1; - return 0; + kfree(buf); + + return ret; } static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input) { struct uvc_fh *handle = fh; struct uvc_video_chain *chain = handle->chain; + u8 *buf; int ret; - u32 i; ret = uvc_acquire_privileges(handle); if (ret < 0) @@ -939,10 +944,17 @@ static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input) if (input >= chain->selector->bNrInPins) return -EINVAL; - i = input + 1; - return uvc_query_ctrl(chain->dev, UVC_SET_CUR, chain->selector->id, - chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, - &i, 1); + buf = kmalloc(1, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + *buf = input + 1; + ret = uvc_query_ctrl(chain->dev, UVC_SET_CUR, chain->selector->id, + chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL, + buf, 1); + kfree(buf); + + return ret; } static int uvc_ioctl_queryctrl(struct file *file, void *fh,