From patchwork Wed Aug 8 20:24:00 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steve Conklin X-Patchwork-Id: 175953 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from chlorine.canonical.com (chlorine.canonical.com [91.189.94.204]) by ozlabs.org (Postfix) with ESMTP id 3971E2C00A3 for ; Thu, 9 Aug 2012 06:24:23 +1000 (EST) Received: from localhost ([127.0.0.1] helo=chlorine.canonical.com) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1SzCnb-00059D-9t; Wed, 08 Aug 2012 20:24:11 +0000 Received: from mail-qc0-f177.google.com ([209.85.216.177]) by chlorine.canonical.com with esmtp (Exim 4.71) (envelope-from ) id 1SzCnZ-000598-C9 for kernel-team@lists.ubuntu.com; Wed, 08 Aug 2012 20:24:09 +0000 Received: by qcsu28 with SMTP id u28so895347qcs.8 for ; Wed, 08 Aug 2012 13:24:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:subject:date:message-id:x-mailer; bh=8opUOH5i1IshnTIDuHnARL/LmSyxOMibpO3iePGdtxU=; b=lFwB49+L1CEaheGIHR9gCl7mskpKgX/PEnEdna187F2bbBstWvXabjIHU9xCekh8E0 I8mr/N6WZy2cHaVm8IjTaK0eWyQTCANdiMrD4Eqo2MfRDjJTs3R+ZrxE1+6UQPRhJYVh zMcj6MtaE7dD7c66VSwhU2Dq8SCPFNHiC+2jrMoYnyF4NnUc0txu4NaUvTB42qKEdzXY 3C9jwpI4Z8LU71sXUkJnptbAIES+7uW/gI5yY3SUK0eD4MJIvqjLKceBwmCL1zTzJVKZ lUG2/djUNqJjQeY4kh2NhzLGZoJLVkgVnCHcm8jGgQHeOsplXUzwlbhCBAA7J0CtmTcR XfPQ== Received: by 10.224.185.148 with SMTP id co20mr32292970qab.4.1344457448733; Wed, 08 Aug 2012 13:24:08 -0700 (PDT) Received: from localhost.localdomain (user-69-73-1-154.knology.net. [69.73.1.154]) by mx.google.com with ESMTPS id ej6sm19475534qab.0.2012.08.08.13.24.07 (version=TLSv1/SSLv3 cipher=OTHER); Wed, 08 Aug 2012 13:24:08 -0700 (PDT) From: Steve Conklin To: kernel-team@lists.ubuntu.com Subject: [lucid] [CVE-2012-0044] drm: integer overflow in drm_mode_dirtyfb_ioctl() Date: Wed, 8 Aug 2012 15:24:00 -0500 Message-Id: <1344457440-23625-1-git-send-email-sconklin@canonical.com> X-Mailer: git-send-email 1.7.9.5 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.13 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: kernel-team-bounces@lists.ubuntu.com Errors-To: kernel-team-bounces@lists.ubuntu.com From: Xi Wang CVE-2012-0044 BugLink: http://bugs.launchpad.net/bugs/917838 There is a potential integer overflow in drm_mode_dirtyfb_ioctl() if userspace passes in a large num_clips. The call to kmalloc would allocate a small buffer, and the call to fb->funcs->dirty may result in a memory corruption. Reported-by: Haogang Chen Signed-off-by: Xi Wang Cc: stable@kernel.org Signed-off-by: Dave Airlie (cherry picked from commit a5cd335165e31db9dbab636fd29895d41da55dd2) Signed-off-by: Steve Conklin Acked-by: Andy Whitcroft --- drivers/gpu/drm/drm_crtc.c | 4 ++++ include/drm/drm_mode.h | 2 ++ 2 files changed, 6 insertions(+) diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 405c63b..8323fc3 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1873,6 +1873,10 @@ int drm_mode_dirtyfb_ioctl(struct drm_device *dev, } if (num_clips && clips_ptr) { + if (num_clips < 0 || num_clips > DRM_MODE_FB_DIRTY_MAX_CLIPS) { + ret = -EINVAL; + goto out_err1; + } clips = kzalloc(num_clips * sizeof(*clips), GFP_KERNEL); if (!clips) { ret = -ENOMEM; diff --git a/include/drm/drm_mode.h b/include/drm/drm_mode.h index d30bedf..ddd46db 100644 --- a/include/drm/drm_mode.h +++ b/include/drm/drm_mode.h @@ -235,6 +235,8 @@ struct drm_mode_fb_cmd { #define DRM_MODE_FB_DIRTY_ANNOTATE_FILL 0x02 #define DRM_MODE_FB_DIRTY_FLAGS 0x03 +#define DRM_MODE_FB_DIRTY_MAX_CLIPS 256 + /* * Mark a region of a framebuffer as dirty. *