Re: [PATCH bpf-next v2 4/4] selftest: bpf: Test copying a sockmap and sockhash

On Tue, 29 Sep 2020 at 07:06, Martin KaFai Lau kafai@fb.com wrote:

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• /* We need a temporary buffer on the stack, since the verifier doesn't
  

•  * let us use the pointer from the context as an argument to the helper.
  

Is it something that can be improved later?

others LGTM.

Yeah, I think so. We'd need to do something similar to your sock_common work for PTR_TO_RDONLY_BUF_OR_NULL. The fact that the pointer is read only makes it a bit more difficult I think. After that, a user could just plug the key into map_update_elem directly. Alternatively, allow specialising map_ops per context.