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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 21B93C2D0DB for ; Fri, 24 Jan 2020 11:20:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E68772087E for ; Fri, 24 Jan 2020 11:20:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579864820; bh=oEIEXSPuOM0A3P+XkQ2psI6vnvcbHSWtdfSP1ycFFUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jYEclhDPwLJS88PUMDqdl+dVma2Z3PwGshHHvjaf8RY8q+g2Vn3yEOFyrzTPUyPJo ycfc9997kDbBZGR+Fm8yt+muaut/zTIIqvDizIwcF9hGYP+J4tGaZ744s1VFAaWFMM Y6iqipQcAXEpE9mQoJY0k3WdWhSG4kqtVzdGpmes= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390904AbgAXLUT (ORCPT ); Fri, 24 Jan 2020 06:20:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:57816 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390894AbgAXLUP (ORCPT ); Fri, 24 Jan 2020 06:20:15 -0500 Received: from localhost (ip-213-127-102-57.ip.prioritytelecom.net [213.127.102.57]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 81DB92087E; Fri, 24 Jan 2020 11:20:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579864815; bh=oEIEXSPuOM0A3P+XkQ2psI6vnvcbHSWtdfSP1ycFFUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=y4qlB4b1aP7iF641/ZoRIsKiOCgA8I06vjgWP8txBAOVwi3M2/9/MnwhQySTCo42M 94i7peo6+He+bC3kwUL38Dysi/Fo3WVurY1T1Ap1AGcq/zY31ODMN3chlK4HRblOur 1wIcldBgNtj2bZQEknpzSqJupzWxO+D2dVkUr+Fc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.19 360/639] media: omap_vout: potential buffer overflow in vidioc_dqbuf() Date: Fri, 24 Jan 2020 10:28:50 +0100 Message-Id: <20200124093132.198769408@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter [ Upstream commit dd6e2a981bfe83aa4a493143fd8cf1edcda6c091 ] The "b->index" is a u32 the comes from the user in the ioctl. It hasn't been checked. We aren't supposed to use it but we're instead supposed to use the value that gets written to it when we call videobuf_dqbuf(). The videobuf_dqbuf() first memsets it to zero and then re-initializes it inside the videobuf_status() function. It's this final value which we want. Hans Verkuil pointed out that we need to check the return from videobuf_dqbuf(). I ended up doing a little cleanup related to that as well. Fixes: 72915e851da9 ("[media] V4L2: OMAP: VOUT: dma map and unmap v4l2 buffers in qbuf and dqbuf") Signed-off-by: Dan Carpenter Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Sasha Levin --- drivers/media/platform/omap/omap_vout.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/media/platform/omap/omap_vout.c b/drivers/media/platform/omap/omap_vout.c index 5700b7818621d..45511d24d5705 100644 --- a/drivers/media/platform/omap/omap_vout.c +++ b/drivers/media/platform/omap/omap_vout.c @@ -1527,23 +1527,20 @@ static int vidioc_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b) unsigned long size; struct videobuf_buffer *vb; - vb = q->bufs[b->index]; - if (!vout->streaming) return -EINVAL; - if (file->f_flags & O_NONBLOCK) - /* Call videobuf_dqbuf for non blocking mode */ - ret = videobuf_dqbuf(q, (struct v4l2_buffer *)b, 1); - else - /* Call videobuf_dqbuf for blocking mode */ - ret = videobuf_dqbuf(q, (struct v4l2_buffer *)b, 0); + ret = videobuf_dqbuf(q, b, !!(file->f_flags & O_NONBLOCK)); + if (ret) + return ret; + + vb = q->bufs[b->index]; addr = (unsigned long) vout->buf_phy_addr[vb->i]; size = (unsigned long) vb->size; dma_unmap_single(vout->vid_dev->v4l2_dev.dev, addr, size, DMA_TO_DEVICE); - return ret; + return 0; } static int vidioc_streamon(struct file *file, void *fh, enum v4l2_buf_type i) -- 2.20.1