Re: [PATCH 4/8] pipe: fix limit checking in pipe_set_size()

[Willy Tarreau]

Hi Michael,

Since you're changing this code, it's probably worth swapping the size
check and capable() below to save a function call in the normal path :

On Fri, Aug 19, 2016 at 05:25:35PM +1200, Michael Kerrisk (man-pages) wrote:
> +	if (nr_pages > pipe->buffers) {
> +		if (!capable(CAP_SYS_RESOURCE) && size > pipe_max_size) {

=>		if (size > pipe_max_size && !capable(CAP_SYS_RESOURCE)) {

> +			ret = -EPERM;
> +			goto out_revert_acct;
> +		} else if ((too_many_pipe_buffers_hard(pipe->user) ||
> +				too_many_pipe_buffers_soft(pipe->user)) &&
> +				!capable(CAP_SYS_RESOURCE) &&
> +				!capable(CAP_SYS_ADMIN)) {
> +			ret = -EPERM;
> +			goto out_revert_acct;
> +		}
> +	}
(...)

Cheers,
Willy