Re: [PATCH V3 05/12] io_uring: bpf: extend io_uring with bpf struct_ops

[Jens Axboe <axboe@kernel.dk>]

On 3/24/26 10:37 AM, Ming Lei wrote:
>  int io_uring_bpf_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
>  {
> +	struct uring_bpf_data *data = io_kiocb_to_cmd(req, struct uring_bpf_data);
> +	u32 opf = READ_ONCE(sqe->bpf_op_flags);
> +	unsigned char bpf_op = uring_bpf_get_op(opf);
> +	const struct uring_bpf_ops *ops;
> +
> +	if (unlikely(!(req->ctx->flags & IORING_SETUP_BPF_EXT)))
> +		goto fail;
> +
> +	if (bpf_op >= IO_RING_MAX_BPF_OPS)
> +		return -EINVAL;
> +
> +	ops = req->ctx->bpf_ext_ops[bpf_op].ops;
> +	data->opf = opf;
> +	data->ops = ops;
> +	if (ops && ops->prep_fn)
> +		return ops->prep_fn(data, sqe);
> +fail:
>  	return -EOPNOTSUPP;
>  }

Any early exit should ensure 'data' is sane, so that the cleanup doesn't
potentially touch uninitialized crap. This is something that has bit us
in the past. Not an issue for this patch that adds the code, but it will
be once the next patch is applied. Better to clear ->opf/ops here
upfront, so that we never leave this function without 'data' being fully
initialized.

-- 
Jens Axboe