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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY 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 E362FC55178 for ; Fri, 23 Oct 2020 11:34:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 85877221F9 for ; Fri, 23 Oct 2020 11:34:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="B8KcomkT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S463052AbgJWLeh (ORCPT ); Fri, 23 Oct 2020 07:34:37 -0400 Received: from aserp2130.oracle.com ([141.146.126.79]:43964 "EHLO aserp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S462980AbgJWLeg (ORCPT ); Fri, 23 Oct 2020 07:34:36 -0400 Received: from pps.filterd (aserp2130.oracle.com [127.0.0.1]) by aserp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09NBOxfq013150; Fri, 23 Oct 2020 11:34:19 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : mime-version : content-type; s=corp-2020-01-29; bh=tbKiGTsT3s13Xp9OSxn215JhwhGeMxGx2qrXzzVgyvI=; b=B8KcomkT8cV4HfCW1C7w22aZJIcXSiso+p9BX+YeETprhJNWQPMo4Of4gMPkBbrh4bWA rWUrXWUEf2+bdC5TQI9TbLRMEwLri58JhRW7nk6bgKlXqWTBMLZlyyawWSDJIti+8CJU PM4/VccVK7Shix04PVGJDqp5icPvr9GyOCZrQDqirUEzC20hnRWGMpdW1HhVJWRDeAl5 rBERygRKZlpEVdSANOYYk/JOlI01IFHQtVti0m/9E+BDf7o+AB/Dc2i+7iWOPn0wWKMJ e41JXGGWJq2KW4G/Li6tTbE7ap35E9ojfgmfM5BGF++o0yyutSgGK50/M+JKrUQGqbKy TQ== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by aserp2130.oracle.com with ESMTP id 347p4barwq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 23 Oct 2020 11:34:18 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 09NBQ2xK151409; Fri, 23 Oct 2020 11:34:18 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userp3020.oracle.com with ESMTP id 34ak1ayjv2-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 23 Oct 2020 11:34:18 +0000 Received: from abhmp0017.oracle.com (abhmp0017.oracle.com [141.146.116.23]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 09NBYBgc010958; Fri, 23 Oct 2020 11:34:11 GMT Received: from mwanda (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 23 Oct 2020 04:34:10 -0700 Date: Fri, 23 Oct 2020 14:34:01 +0300 From: Dan Carpenter To: Jani Nikula , Christoph Hellwig Cc: Joonas Lahtinen , Rodrigo Vivi , David Airlie , Daniel Vetter , Tvrtko Ursulin , Andrew Morton , Matthew Auld , Chris Wilson , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [PATCH] drm/i915: Fix a crash in shmem_pin_map() error handling Message-ID: <20201023113401.GG282278@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mailer: git-send-email haha only kidding X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9782 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 mlxscore=0 phishscore=0 spamscore=0 adultscore=0 mlxlogscore=999 malwarescore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010230081 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9782 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 priorityscore=1501 clxscore=1011 malwarescore=0 mlxscore=0 bulkscore=0 lowpriorityscore=0 phishscore=0 adultscore=0 mlxlogscore=999 impostorscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2010230081 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is a signedness bug in shmem_pin_map() error handling because "i" is unsigned. The "while (--i >= 0)" will loop forever until the system crashes. Fixes: bfed6708d6c9 ("drm/i915: use vmap in shmem_pin_map") Signed-off-by: Dan Carpenter --- drivers/gpu/drm/i915/gt/shmem_utils.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/shmem_utils.c b/drivers/gpu/drm/i915/gt/shmem_utils.c index f011ea42487e..7eb542018219 100644 --- a/drivers/gpu/drm/i915/gt/shmem_utils.c +++ b/drivers/gpu/drm/i915/gt/shmem_utils.c @@ -52,8 +52,9 @@ struct file *shmem_create_from_object(struct drm_i915_gem_object *obj) void *shmem_pin_map(struct file *file) { struct page **pages; - size_t n_pages, i; + size_t n_pages; void *vaddr; + int i; n_pages = file->f_mapping->host->i_size >> PAGE_SHIFT; pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL); -- 2.28.0