Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756799Ab2HFRHY (ORCPT ); Mon, 6 Aug 2012 13:07:24 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:51997 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752497Ab2HFRHU (ORCPT ); Mon, 6 Aug 2012 13:07:20 -0400 From: Stefan Bader To: Xi Wang Cc: Dave Airlie , Stefan Bader , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [2.6.32+drm33-longterm] Patch "drm: integer overflow in drm_mode_dirtyfb_ioctl()" has been added to staging queue Date: Mon, 6 Aug 2012 19:07:16 +0200 Message-Id: <1344272836-32514-1-git-send-email-stefan.bader@canonical.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2582 Lines: 76 This is a note to let you know that I have just added a patch titled drm: integer overflow in drm_mode_dirtyfb_ioctl() to the drm-next branch of the 2.6.32+drm33-longterm tree which can be found at http://git.kernel.org/?p=linux/kernel/git/smb/linux-2.6.32.y-drm33.z.git;a=shortlog;h=refs/heads/drm-next or http://kernel.ubuntu.com/git?p=smb/linux-2.6.32.y-drm33.z.git;a=shortlog;h=refs/heads/drm-next If you, or anyone else, feels it should not be added to the drm33-longterm tree, please reply to this email not later than 8 days after this email was sent. Thanks. -Stefan ------ >From a5cd335165e31db9dbab636fd29895d41da55dd2 Mon Sep 17 00:00:00 2001 From: Xi Wang Date: Wed, 23 Nov 2011 01:12:01 -0500 Subject: [PATCH] drm: integer overflow in drm_mode_dirtyfb_ioctl() 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 upstream) Signed-off-by: Stefan Bader --- 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. * -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/