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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 E8F71C33CAF for ; Thu, 16 Jan 2020 17:07:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C050520663 for ; Thu, 16 Jan 2020 17:07:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194435; bh=Gs31IuVAjx8wN9Pan7ak3hf915MS9bR82/HYp0eCCgA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QzW2KtmGAL/5LpZ21bWr+F2p6Wxc3BjdmB5AA0n8K0gQ0xeEA6GDMrKf5IFpHpiXh 3Reyf81Oy0I0do7mbkUzhlf0ZGQh/GIZ+osXVkJL7J3v0ioYzuG4Bsg38ItHYkDrXL 5DooEexLFBBcw9UWrPpnOAZ+7dmxCePRgqwRKo9Y= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389115AbgAPRHO (ORCPT ); Thu, 16 Jan 2020 12:07:14 -0500 Received: from mail.kernel.org ([198.145.29.99]:38546 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388650AbgAPRHJ (ORCPT ); Thu, 16 Jan 2020 12:07:09 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9C52D2081E; Thu, 16 Jan 2020 17:07:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579194428; bh=Gs31IuVAjx8wN9Pan7ak3hf915MS9bR82/HYp0eCCgA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=esSCedNLhqfVIw/5C1sR+IFopXmp5XopEEhcvOldxJ0nTUyXhdVttaLUAPWQSezcT LstrjGFXtXxJfiJYK+STQ4PXoFIWRVrEiHW9PngSmuTBe1UXyD0AEv6K+QbTBCSCvg W9AVFyJWfFbvwfARM9L+i1WSNo6LpWyRtJeSGZ/4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Hans Verkuil , Mauro Carvalho Chehab , Sasha Levin , linux-media@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 345/671] media: omap_vout: potential buffer overflow in vidioc_dqbuf() Date: Thu, 16 Jan 2020 11:59:43 -0500 Message-Id: <20200116170509.12787-82-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116170509.12787-1-sashal@kernel.org> References: <20200116170509.12787-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 5700b7818621..45511d24d570 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