Messages in this thread Patch in this message | | | From | Stefan Bader <> | 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 |
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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
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From a5cd335165e31db9dbab636fd29895d41da55dd2 Mon Sep 17 00:00:00 2001 From: Xi Wang <xi.wang@gmail.com> 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 <haogangchen@gmail.com> Signed-off-by: Xi Wang <xi.wang@gmail.com> Cc: stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
(cherry-picked from commit a5cd335165e31db9dbab636fd29895d41da55dd2 upstream) Signed-off-by: Stefan Bader <stefan.bader@canonical.com> --- 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
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