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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 96959C38A2A for ; Fri, 8 May 2020 13:24:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6284D218AC for ; Fri, 8 May 2020 13:24:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588944270; bh=4+dF0MoF2Yn0zjVZA8KyJ1Sam41xz6ts58v5B6sDwDs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=nhtmtTydbdjMejG89PuRzU7mBo5VxSyke86zv9XqTd/kXmnt32H4n008L+xQt5ch8 d4RDoD1wuy7D3Zsv88aMMaHIOCV8NjVbTzufSc1vbNgActZJNuWLkgeKqoPs4/UUdN SwKqHNEnROwuEm3e1pMWXCM339WBkX4GwmSCXZ00= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728840AbgEHNY3 (ORCPT ); Fri, 8 May 2020 09:24:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:50294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727834AbgEHMgn (ORCPT ); Fri, 8 May 2020 08:36:43 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 D793B21582; Fri, 8 May 2020 12:36:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588941402; bh=4+dF0MoF2Yn0zjVZA8KyJ1Sam41xz6ts58v5B6sDwDs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=emHt4fLUc4qSHFxsGLQCkpdXunOxDd7EBKzN4nAvi9cfszO5u/72y8kqc4HtdERym 70OWxArBl8v7FPiKgT8NlxM7WJLlwUUP4AzHn2DsPG97lsVUjuSM/49WiLnMA7cY8Z d8FpvoFbl7J19UsJ95h6KGCf9qyK8CtjIRE8Hrz0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vasily Averin , Gerd Hoffmann Subject: [PATCH 4.4 002/312] drm/qxl: qxl_release use after free Date: Fri, 8 May 2020 14:29:53 +0200 Message-Id: <20200508123124.719884469@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200508123124.574959822@linuxfoundation.org> References: <20200508123124.574959822@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: Vasily Averin commit 933db73351d359f74b14f4af095808260aff11f9 upstream. qxl_release should not be accesses after qxl_push_*_ring_release() calls: userspace driver can process submitted command quickly, move qxl_release into release_ring, generate interrupt and trigger garbage collector. It can lead to crashes in qxl driver or trigger memory corruption in some kmalloc-192 slab object Gerd Hoffmann proposes to swap the qxl_release_fence_buffer_objects() + qxl_push_{cursor,command}_ring_release() calls to close that race window. cc: stable@vger.kernel.org Fixes: f64122c1f6ad ("drm: add new QXL driver. (v1.4)") Signed-off-by: Vasily Averin Link: http://patchwork.freedesktop.org/patch/msgid/fa17b338-66ae-f299-68fe-8d32419d9071@virtuozzo.com Signed-off-by: Gerd Hoffmann Signed-off-by: Vasily Averin Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/qxl/qxl_cmd.c | 5 ++--- drivers/gpu/drm/qxl/qxl_display.c | 6 +++--- drivers/gpu/drm/qxl/qxl_draw.c | 8 ++++---- drivers/gpu/drm/qxl/qxl_ioctl.c | 5 +---- 4 files changed, 10 insertions(+), 14 deletions(-) --- a/drivers/gpu/drm/qxl/qxl_cmd.c +++ b/drivers/gpu/drm/qxl/qxl_cmd.c @@ -529,8 +529,8 @@ int qxl_hw_surface_alloc(struct qxl_devi /* no need to add a release to the fence for this surface bo, since it is only released when we ask to destroy the surface and it would never signal otherwise */ - qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false); qxl_release_fence_buffer_objects(release); + qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false); surf->hw_surf_alloc = true; spin_lock(&qdev->surf_id_idr_lock); @@ -572,9 +572,8 @@ int qxl_hw_surface_dealloc(struct qxl_de cmd->surface_id = id; qxl_release_unmap(qdev, release, &cmd->release_info); - qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false); - qxl_release_fence_buffer_objects(release); + qxl_push_command_ring_release(qdev, release, QXL_CMD_SURFACE, false); return 0; } --- a/drivers/gpu/drm/qxl/qxl_display.c +++ b/drivers/gpu/drm/qxl/qxl_display.c @@ -292,8 +292,8 @@ qxl_hide_cursor(struct qxl_device *qdev) cmd->type = QXL_CURSOR_HIDE; qxl_release_unmap(qdev, release, &cmd->release_info); - qxl_push_cursor_ring_release(qdev, release, QXL_CMD_CURSOR, false); qxl_release_fence_buffer_objects(release); + qxl_push_cursor_ring_release(qdev, release, QXL_CMD_CURSOR, false); return 0; } @@ -390,8 +390,8 @@ static int qxl_crtc_cursor_set2(struct d cmd->u.set.visible = 1; qxl_release_unmap(qdev, release, &cmd->release_info); - qxl_push_cursor_ring_release(qdev, release, QXL_CMD_CURSOR, false); qxl_release_fence_buffer_objects(release); + qxl_push_cursor_ring_release(qdev, release, QXL_CMD_CURSOR, false); /* finish with the userspace bo */ ret = qxl_bo_reserve(user_bo, false); @@ -450,8 +450,8 @@ static int qxl_crtc_cursor_move(struct d cmd->u.position.y = qcrtc->cur_y + qcrtc->hot_spot_y; qxl_release_unmap(qdev, release, &cmd->release_info); - qxl_push_cursor_ring_release(qdev, release, QXL_CMD_CURSOR, false); qxl_release_fence_buffer_objects(release); + qxl_push_cursor_ring_release(qdev, release, QXL_CMD_CURSOR, false); return 0; } --- a/drivers/gpu/drm/qxl/qxl_draw.c +++ b/drivers/gpu/drm/qxl/qxl_draw.c @@ -245,8 +245,8 @@ void qxl_draw_opaque_fb(const struct qxl qxl_bo_physical_address(qdev, dimage->bo, 0); qxl_release_unmap(qdev, release, &drawable->release_info); - qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); qxl_release_fence_buffer_objects(release); + qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); out_free_palette: if (palette_bo) @@ -385,8 +385,8 @@ void qxl_draw_dirty_fb(struct qxl_device } qxl_bo_kunmap(clips_bo); - qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); qxl_release_fence_buffer_objects(release); + qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); out_release_backoff: if (ret) @@ -436,8 +436,8 @@ void qxl_draw_copyarea(struct qxl_device drawable->u.copy_bits.src_pos.y = sy; qxl_release_unmap(qdev, release, &drawable->release_info); - qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); qxl_release_fence_buffer_objects(release); + qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); out_free_release: if (ret) @@ -480,8 +480,8 @@ void qxl_draw_fill(struct qxl_draw_fill qxl_release_unmap(qdev, release, &drawable->release_info); - qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); qxl_release_fence_buffer_objects(release); + qxl_push_command_ring_release(qdev, release, QXL_CMD_DRAW, false); out_free_release: if (ret) --- a/drivers/gpu/drm/qxl/qxl_ioctl.c +++ b/drivers/gpu/drm/qxl/qxl_ioctl.c @@ -257,11 +257,8 @@ static int qxl_process_single_command(st apply_surf_reloc(qdev, &reloc_info[i]); } + qxl_release_fence_buffer_objects(release); ret = qxl_push_command_ring_release(qdev, release, cmd->type, true); - if (ret) - qxl_release_backoff_reserve_list(release); - else - qxl_release_fence_buffer_objects(release); out_free_bos: out_free_release: