From patchwork Wed Mar 21 15:45:53 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 10299737 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A3D2460385 for ; Wed, 21 Mar 2018 15:45:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A1EE528DAF for ; Wed, 21 Mar 2018 15:45:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 95B0D297F8; Wed, 21 Mar 2018 15:45:58 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 1FAB928DAF for ; Wed, 21 Mar 2018 15:45:57 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id DAC076E049; Wed, 21 Mar 2018 15:45:56 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3FD5B6E049 for ; Wed, 21 Mar 2018 15:45:55 +0000 (UTC) Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id B13A4FBC; Wed, 21 Mar 2018 15:45:54 +0000 (UTC) Date: Wed, 21 Mar 2018 16:45:53 +0100 From: Greg Kroah-Hartman To: David Airlie Subject: [PATCH] drm: udl: Properly check framebuffer mmap offsets Message-ID: <20180321154553.GA18454@kroah.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Tom Lendacky , Daniel Vetter , Eyal Itkin , Krzysztof Kozlowski , Cihangir Akturk , dri-devel@lists.freedesktop.org, Ingo Molnar Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The memmap options sent to the udl framebuffer driver were not being checked for all sets of possible crazy values. Fix this up by properly bounding the allowed values. Reported-by: Eyal Itkin Cc: stable Signed-off-by: Greg Kroah-Hartman diff --git a/drivers/gpu/drm/udl/udl_fb.c b/drivers/gpu/drm/udl/udl_fb.c index b5b335c9b2bb..2ebdc6d5a76e 100644 --- a/drivers/gpu/drm/udl/udl_fb.c +++ b/drivers/gpu/drm/udl/udl_fb.c @@ -159,10 +159,15 @@ static int udl_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) { unsigned long start = vma->vm_start; unsigned long size = vma->vm_end - vma->vm_start; - unsigned long offset = vma->vm_pgoff << PAGE_SHIFT; + unsigned long offset; unsigned long page, pos; - if (offset + size > info->fix.smem_len) + if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) + return -EINVAL; + + offset = vma->vm_pgoff << PAGE_SHIFT; + + if (offset > info->fix.smem_len || size > info->fix.smem_len - offset) return -EINVAL; pos = (unsigned long)info->fix.smem_start + offset;