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: Jiri Slaby <jslaby@xxxxxxx> Signed-off-by: Willy Tarreau <w@xxxxxx> --- drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c b/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c index c509d40..f435b6c 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_ioctl.c @@ -90,7 +90,7 @@ int vmw_get_cap_3d_ioctl(struct drm_device *dev, void *data, void *bounce; int ret; - if (unlikely(arg->pad64 != 0)) { + if (unlikely(arg->pad64 != 0 || arg->max_size == 0)) { DRM_ERROR("Illegal GET_3D_CAP argument.\n"); return -EINVAL; } -- 2.8.0.rc2.1.gbe9624a