drm/vmwgfx: limit the number of mip levels in vmw_gb_surface_define_ioctl()
authorVladis Dronov <vdronov@redhat.com>
Fri, 2 Jun 2017 05:42:09 +0000 (07:42 +0200)
committerThomas Hellstrom <thellstrom@vmware.com>
Wed, 7 Jun 2017 10:07:35 +0000 (12:07 +0200)
commitee9c4e681ec4f58e42a83cb0c22a0289ade1aacf
treeb0ffe1b2073a8c749c18e9e99696df602f9637a0
parente5b4ab1ffbe2553ee278cb1b6bcb671a31d86518
drm/vmwgfx: limit the number of mip levels in vmw_gb_surface_define_ioctl()

The 'req->mip_levels' parameter in vmw_gb_surface_define_ioctl() is
a user-controlled 'uint32_t' value which is used as a loop count limit.
This can lead to a kernel lockup and DoS. Add check for 'req->mip_levels'.

References:
https://bugzilla.redhat.com/show_bug.cgi?id=1437431

Cc: <stable@vger.kernel.org>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
drivers/gpu/drm/vmwgfx/vmwgfx_surface.c