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,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 84F44C433DF for ; Sun, 18 Oct 2020 19:29:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 54FDB20791 for ; Sun, 18 Oct 2020 19:29:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603049352; bh=wDUYPS56b/18VlLZ2KLd4bd6O6ujEctojC7MEYgAW6o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cj8UZ8lNAhcbFAOLkFSShu2ghzsv2gqQmSud5eVjtYcz534Oz8/v4NxxB5tjtllsO ijoajs7cixV/Hz4fW2Rw+PEyir5Zxy1hJjtErTD1DFx7HfRV+MxipNyIlJktA7lr6y F7kDRXUAA9pQ1TQxwx3VT2I0FBqeGierb+bplYj8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731669AbgJRT3L (ORCPT ); Sun, 18 Oct 2020 15:29:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:44316 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732206AbgJRT2B (ORCPT ); Sun, 18 Oct 2020 15:28:01 -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 5A05D22267; Sun, 18 Oct 2020 19:28:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1603049281; bh=wDUYPS56b/18VlLZ2KLd4bd6O6ujEctojC7MEYgAW6o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nmFR4Nk1r9NuNN/GuVrgjpSA0kiXXoC3OVA6zhkbkeEyMbDPvnvXfsuwePNGxSbmt bFyTTnTR/EAS4Q/E6fP4f6xA3kmzbv6bEuwwXmnOYzqI3tVgEHuGTAtCoTGA/GzaiK TvKhvg3EmWenoAVYFGAMLgXwlNH4K26oWxdcaCqQ= 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 4.4 27/33] Fix use after free in get_capset_info callback. Date: Sun, 18 Oct 2020 15:27:22 -0400 Message-Id: <20201018192728.4056577-27-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201018192728.4056577-1-sashal@kernel.org> References: <20201018192728.4056577-1-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 06496a1281622..476b9993b0682 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 772a5a3b0ce1a..18e8fcad6690b 100644 --- a/drivers/gpu/drm/virtio/virtgpu_vq.c +++ b/drivers/gpu/drm/virtio/virtgpu_vq.c @@ -596,9 +596,13 @@ 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