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=-13.1 required=3.0 tests=BAYES_00,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=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 D23E9C433DF for ; Sun, 18 Oct 2020 19:43:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A279D206ED for ; Sun, 18 Oct 2020 19:43:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603050180; bh=wQr68+vYs99n5H4ysvc98rbX0sn/3HNW51O3srouVyc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=y+XENm+29qkw+FCIXmcngR0OVDPeK83SAZFe+C9SGr1x6WPjQiY8InSaPeofwlX5P 9enK54qCBWmcuLjkN7exqwlO9ABedc9Tb0AQo6Z6OBC/hYQFmH4iiPQYEwgMaDLEfO V9G0LmlEv7PF2/+o3Lp0uzV5ptAOyrlOu7IalsLc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733063AbgJRTm7 (ORCPT ); Sun, 18 Oct 2020 15:42:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:37326 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730425AbgJRTXs (ORCPT ); Sun, 18 Oct 2020 15:23:48 -0400 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 C6B6A2137B; Sun, 18 Oct 2020 19:23:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603049027; bh=wQr68+vYs99n5H4ysvc98rbX0sn/3HNW51O3srouVyc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jaTC+cfrSOGz/AAr1SZTYNNhetLBHRBt0OWSdimXB/7/+SD0XvP8J0dm+y5vCtMgo a6XsyUNNR/6oNUcMyknLBFi7ibvmgG3kpElwhh2XS+0AgpbdFk0NDurktWJJ0Txj39 uSU6hLe8lH3EMmCFxRiZ3SfZPU6dORV32eDjAR30= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Doug Horn , Gerd Hoffmann , Sasha Levin , dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org Subject: [PATCH AUTOSEL 5.4 60/80] Fix use after free in get_capset_info callback. Date: Sun, 18 Oct 2020 15:22:11 -0400 Message-Id: <20201018192231.4054535-60-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201018192231.4054535-1-sashal@kernel.org> References: <20201018192231.4054535-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Doug Horn [ Upstream commit e219688fc5c3d0d9136f8d29d7e0498388f01440 ] If a response to virtio_gpu_cmd_get_capset_info takes longer than five seconds to return, the callback will access freed kernel memory in vg->capsets. Signed-off-by: Doug Horn Link: http://patchwork.freedesktop.org/patch/msgid/20200902210847.2689-2-gurchetansingh@chromium.org Signed-off-by: Gerd Hoffmann Signed-off-by: Sasha Levin --- drivers/gpu/drm/virtio/virtgpu_kms.c | 2 ++ drivers/gpu/drm/virtio/virtgpu_vq.c | 10 +++++++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_kms.c b/drivers/gpu/drm/virtio/virtgpu_kms.c index c190702fab726..6dcc05ab31eba 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -96,8 +96,10 @@ static void virtio_gpu_get_capsets(struct virtio_gpu_device *vgdev, vgdev->capsets[i].id > 0, 5 * HZ); if (ret == 0) { DRM_ERROR("timed out waiting for cap set %d\n", i); + spin_lock(&vgdev->display_info_lock); kfree(vgdev->capsets); vgdev->capsets = NULL; + spin_unlock(&vgdev->display_info_lock); return; } DRM_INFO("cap set %d: id %d, max-version %d, max-size %d\n", diff --git a/drivers/gpu/drm/virtio/virtgpu_vq.c b/drivers/gpu/drm/virtio/virtgpu_vq.c index 7ac20490e1b4c..92022a83bbd5e 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -572,9 +572,13 @@ static void virtio_gpu_cmd_get_capset_info_cb(struct virtio_gpu_device *vgdev, int i = le32_to_cpu(cmd->capset_index); spin_lock(&vgdev->display_info_lock); - vgdev->capsets[i].id = le32_to_cpu(resp->capset_id); - vgdev->capsets[i].max_version = le32_to_cpu(resp->capset_max_version); - vgdev->capsets[i].max_size = le32_to_cpu(resp->capset_max_size); + if (vgdev->capsets) { + vgdev->capsets[i].id = le32_to_cpu(resp->capset_id); + vgdev->capsets[i].max_version = le32_to_cpu(resp->capset_max_version); + vgdev->capsets[i].max_size = le32_to_cpu(resp->capset_max_size); + } else { + DRM_ERROR("invalid capset memory."); + } spin_unlock(&vgdev->display_info_lock); wake_up(&vgdev->resp_wq); } -- 2.25.1