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Subject: Re: [PATCH v2 1/3] bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)
To:     Jakub Kicinski <kuba@kernel.org>,
        Alexei Starovoitov <alexei.starovoitov@gmail.com>
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From:   Daniel Borkmann <daniel@iogearbox.net>
Message-ID: <bcc5fbaf-83f3-cc05-67b3-512b44818321@iogearbox.net>
Date:   Wed, 19 Jul 2023 16:51:51 +0200
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On 7/19/23 1:21 AM, Jakub Kicinski wrote:
> On Tue, 18 Jul 2023 16:17:24 -0700 Alexei Starovoitov wrote:
>> Which would encourage bnxt-like hacks.
>> I don't like it tbh.
>> At least skb_pointer_if_linear() has a clear meaning.
>> It's more run-time overhead, since buffer__opt is checked early,
>> but that's ok.
> 
> Alright, your version fine by me, too. Thanks!

Looks good to me too. Agree that the !buffer check should not live in
__skb_header_pointer() and is better handled in the bpf_dynptr_slice()
internals.

Thanks,
Daniel