From patchwork Tue Oct 27 13:50:30 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 311819 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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 25DEEC4363A for ; Tue, 27 Oct 2020 18:05:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C966F22258 for ; Tue, 27 Oct 2020 18:05:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603821941; bh=XmtH0B5d3U1FNGvtemeJjeJBz814mke7qpOlX3I7Z/g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=GkQsm2CSoZHxDEuYTHNc97mPnhLU4pzRtKd9Z9ovRVzRh/QrsYwDcUya51rL9b/3o wUo7rCj+67PI6ERrN4ydx+8F1EmeC0P6IVTv4j4Ba2R/LnOzHucT9midPXH2v2ffRr UksIQLYz31Sakf1jAQWZxylEG1Lo7n4AcxbgnclY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757220AbgJ0OQu (ORCPT ); Tue, 27 Oct 2020 10:16:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:39302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757213AbgJ0OQt (ORCPT ); Tue, 27 Oct 2020 10:16:49 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 2EA5822281; Tue, 27 Oct 2020 14:16:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603808208; bh=XmtH0B5d3U1FNGvtemeJjeJBz814mke7qpOlX3I7Z/g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tEgHbChDEfsJHkDYLec2CPvryIhsPa7Co3lvWIO3Xhr9eSby4r/WxLXYhKkSp+zzr ik7Ed3X919urwA6NXVECyrpistwPqjMxjuX2bGNavRB2y0n5/B/82hygoGauSyauLr fpO+c7MjjayhGHtIMP6LPrO3YtDVGwJu7ZoH/dpE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Doug Horn , Gerd Hoffmann , Sasha Levin Subject: [PATCH 4.14 175/191] Fix use after free in get_capset_info callback. Date: Tue, 27 Oct 2020 14:50:30 +0100 Message-Id: <20201027134918.145991503@linuxfoundation.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201027134909.701581493@linuxfoundation.org> References: <20201027134909.701581493@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 6400506a06b07..bed450fbb2168 100644 --- a/drivers/gpu/drm/virtio/virtgpu_kms.c +++ b/drivers/gpu/drm/virtio/virtgpu_kms.c @@ -113,8 +113,10 @@ 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 a3be65e689fd2..a956c73ea85e5 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -563,9 +563,13 @@ 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); }