Re: [PATCH 07/11] io_uring: add new api to register fixed workers

[Ammar Faizi <ammarfaizi2@gnuweeb.org>]

On Fri, Jun 09, 2023 at 08:20:27PM +0800, Hao Xu wrote:  
> +static __cold int io_register_iowq_fixed_workers(struct io_ring_ctx *ctx,
> +					       void __user *arg, int nr_args)
> +	__must_hold(&ctx->uring_lock)
> +{
> +	struct io_uring_task *tctx = NULL;
> +	struct io_sq_data *sqd = NULL;
> +	struct io_uring_fixed_worker_arg *res;
> +	size_t size;
> +	int i, ret;
> +	bool zero = true;
> +
> +	size = array_size(nr_args, sizeof(*res));
> +	if (size == SIZE_MAX)
> +		return -EOVERFLOW;
> +
> +	res = memdup_user(arg, size);
> +	if (IS_ERR(res))
> +		return PTR_ERR(res);
> +
> +	for (i = 0; i < nr_args; i++) {
> +		if (res[i].nr_workers) {
> +			zero = false;
> +			break;
> +		}
> +	}
> +
> +	if (zero)
> +		return 0;

You have a memory leak bug here. The memdup_user() needs clean up.
kfree(res);

-- 
Ammar Faizi