[PATCH v2] drm/vmwgfx: Fix an uninitialized fence handle value

[Deepak Singh Rawat]

Reviewed-by: Deepak Rawat <drawat at vmware.com>

On Thu, 2019-01-31 at 10:52 +0100, Thomas Hellstrom wrote:
> if vmw_execbuf_fence_commands() fails, The handle value will be
> uninitialized and a bogus fence handle might be copied to user-space.
> 
> Fixes: 2724b2d54cda: ("drm/vmwgfx: Use new validation interface for
> the modesetting code v2")
> Reported-by: Dan Carpenter <dan.carpenter at oracle.com>
> Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
> Reviewed-by: Brian Paul <brianp at vmware.com> #v1
> Reviewed-by: Sinclair Yeh <syeh at vmware.com> #v1
> ---
> v2: Also initialize the ret local variable, to silence compilatior
> warnings.
> Call vmw_execbuf_copy_fence_user regardless of the value of ret, to
> propagate
> the correct error code to user-space.
> ---
>  drivers/gpu/drm/vmwgfx/vmwgfx_kms.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
> b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
> index b351fb5214d3..5e257a600cea 100644
> --- a/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
> +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_kms.c
> @@ -2554,8 +2554,8 @@ void vmw_kms_helper_validation_finish(struct
> vmw_private *dev_priv,
>  				      user_fence_rep)
>  {
>  	struct vmw_fence_obj *fence = NULL;
> -	uint32_t handle;
> -	int ret;
> +	uint32_t handle = 0;
> +	int ret = 0;
>  
>  	if (file_priv || user_fence_rep || vmw_validation_has_bos(ctx)
> ||
>  	    out_fence)