drm/vmwgfx: fix integer overflow in vmw_surface_define_ioctl()
authorLi Qiang <liq3ea@gmail.com>
Tue, 28 Mar 2017 03:10:53 +0000 (20:10 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 12 Apr 2017 10:38:33 +0000 (12:38 +0200)
commitc21636bd64c511160846bdf87ef4c7ff48680c99
tree9c1d263886aa13fb5ac535c4172b7c5c0d3a5782
parent235e914069bd501be22597e6c0176f16b477ae37
drm/vmwgfx: fix integer overflow in vmw_surface_define_ioctl()

commit e7e11f99564222d82f0ce84bd521e57d78a6b678 upstream.

In vmw_surface_define_ioctl(), the 'num_sizes' is the sum of the
'req->mip_levels' array. This array can be assigned any value from
the user space. As both the 'num_sizes' and the array is uint32_t,
it is easy to make 'num_sizes' overflow. The later 'mip_levels' is
used as the loop count. This can lead an oob write. Add the check of
'req->mip_levels' to avoid this.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/gpu/drm/vmwgfx/vmwgfx_surface.c