Re: [PATCH rdma-rc] RDMA/uverbs: Mark ioctl responses with UVERBS_ATTR_F_VALID_OUTPUT

[Bart Van Assche <bvanassche@xxxxxxx>]

On 1/10/19 10:21 PM, Leon Romanovsky wrote:
> --- a/drivers/infiniband/core/uverbs_cmd.c
> +++ b/drivers/infiniband/core/uverbs_cmd.c
> @@ -60,6 +60,10 @@ static int uverbs_response(struct uverbs_attr_bundle *attrs, const void *resp,
>   {
>   	int ret;
>   
> +	if (uverbs_attr_is_valid(attrs, UVERBS_ATTR_CORE_OUT))
> +		return uverbs_copy_to_struct_or_zero(
> +			attrs, UVERBS_ATTR_CORE_OUT, resp, resp_len);
> +
>   	if (copy_to_user(attrs->ucore.outbuf, resp,
>   			 min(attrs->ucore.outlen, resp_len)))
>   		return -EFAULT;
> @@ -1181,6 +1185,9 @@ static int ib_uverbs_poll_cq(struct uverbs_attr_bundle *attrs)
>   		goto out_put;
>   	}
>   
> +	if (uverbs_attr_is_valid(attrs, UVERBS_ATTR_CORE_OUT))
> +		ret = uverbs_output_written(attrs, UVERBS_ATTR_CORE_OUT);
> +
>   	ret = 0;
>   

Hi Leon,

Coverity reports about this code that the value returned by 
uverbs_output_written() is overwritten before it is used.

Bart.