drm/vmwgfx: avoid calling vzalloc with a 0 size in vmw_get_cap_3d_ioctl()

In vmw_get_cap_3d_ioctl(), a user can supply 0 for a size that is
used in vzalloc(). This eventually calls dump_stack() (in warn_alloc()),
which can leak useful addresses to dmesg.

Add check to avoid a size of 0.

Cc: <stable@vger.kernel.org>
Signed-off-by: Murray McAllister <murray.mcallister@insomniasec.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
This commit is contained in:
Murray McAllister 2017-03-27 11:15:12 +02:00 committed by Thomas Hellstrom
parent 36274ab8c5
commit 63774069d9

View File

@ -186,7 +186,7 @@ int vmw_get_cap_3d_ioctl(struct drm_device *dev, void *data,
bool gb_objects = !!(dev_priv->capabilities & SVGA_CAP_GBOBJECTS);
struct vmw_fpriv *vmw_fp = vmw_fpriv(file_priv);
if (unlikely(arg->pad64 != 0)) {
if (unlikely(arg->pad64 != 0 || arg->max_size == 0)) {
DRM_ERROR("Illegal GET_3D_CAP argument.\n");
return -EINVAL;
}