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=-3.8 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,URIBL_BLOCKED autolearn=no 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 22D68C3A5A9 for ; Mon, 4 May 2020 16:40:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E6B5C2073B for ; Mon, 4 May 2020 16:40:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588610406; bh=sgByuzfhKbHojmkKvT8MCOvO9KSXVLWdnDVEzxVaYh8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ejF1w7Fnue/jGG1r9fJy2I1/Hn6cS9+YwecdnK/ZDY+lHpwsh+apbdIvd0rTcSMpK YjIAqiKi5M38+GYWcWelq3akgJy17X7Kx64VWjOFL0akuwZU8299aV5sm//AVhfHAf d9Xt0R6uv2K7mpLMft3+ZUTTWWnjMPXdWY6vn4s4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729779AbgEDQkF (ORCPT ); Mon, 4 May 2020 12:40:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:49246 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729763AbgEDQjS (ORCPT ); Mon, 4 May 2020 12:39:18 -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 25886206D9; Mon, 4 May 2020 16:39:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588610358; bh=sgByuzfhKbHojmkKvT8MCOvO9KSXVLWdnDVEzxVaYh8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WwEBh8fIJPbfXaiP896yZ5JWpTqbvZIAbQtpQQ9C73juh+PVG+94d7jnMqcCcxr6V CtUeVBJNDQlubZD2LU4+nE677X+7XCqOYE5J5WOJp4gpmxOdtT65wUt8x5g3EK9gc/ r1EmDmHcEpFW8rNG+Hw4tdGbpQrlewiJoXZizxPY= Date: Mon, 4 May 2020 18:39:16 +0200 From: Greg KH To: Vasily Averin Cc: stable@vger.kernel.org, Gerd Hoffmann Subject: Re: [PATCH 4.19] drm/qxl: qxl_release use after free Message-ID: <20200504163916.GB2724164@kroah.com> References: <7f93a18b-45de-457d-6901-f6babce1d56a@virtuozzo.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7f93a18b-45de-457d-6901-f6babce1d56a@virtuozzo.com> Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Mon, May 04, 2020 at 02:36:27PM +0300, Vasily Averin wrote: > >>From 933db73351d359f74b14f4af095808260aff11f9 Mon Sep 17 00:00:00 2001 > From: Vasily Averin > Date: Wed, 29 Apr 2020 12:01:24 +0300 > Subject: drm/qxl: qxl_release use after free > > 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 > > backported to v.4.19 stable Now replaced, thansk. greg k-h