diff options
| author | Xi Wang <xi.wang@gmail.com> | 2011-11-23 10:12:01 +0400 |
|---|---|---|
| committer | Paul Gortmaker <paul.gortmaker@windriver.com> | 2012-08-17 23:34:59 +0400 |
| commit | 2d5bea3e719eb7dc957f168155337578acded206 (patch) | |
| tree | b602c50d4efe37d04aee6aec0c058a7b7cbd5668 /drivers/gpu | |
| parent | 3d67f874fd94587baa38869d317d537242baa097 (diff) | |
| download | linux-2d5bea3e719eb7dc957f168155337578acded206.tar.xz | |
drm: integer overflow in drm_mode_dirtyfb_ioctl()
commit a5cd335165e31db9dbab636fd29895d41da55dd2 upstream.
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>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_crtc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 1a224f83a2d8..819d0dc4f2fa 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1833,6 +1833,10 @@ 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; |