4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Murray McAllister <murray.mcallister@xxxxxxxxxxxxxxx>
commit 63774069d9527a1aeaa4aa20e929ef5e8e9ecc38 upstream.
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.
Signed-off-by: Murray McAllister <murray.mcallister@xxxxxxxxxxxxxxx>
Reviewed-by: Sinclair Yeh <syeh@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c
@@ -186,7 +186,7 @@ int vmw_get_cap_3d_ioctl(struct drm_devi
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;
}