netdev - Re: [PATCH bpf-next v7 0/3] Add skb + xdp dynptrs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 15 Jan 2023 14:41:25 +0200
From:   Tariq Toukan <ttoukan.linux@...il.com>
To:     Alexei Starovoitov <alexei.starovoitov@...il.com>,
        Joanne Koong <joannelkoong@...il.com>,
        Kumar Kartikeya Dwivedi <memxor@...il.com>
Cc:     bpf <bpf@...r.kernel.org>, Daniel Borkmann <daniel@...earbox.net>,
        Martin KaFai Lau <martin.lau@...nel.org>,
        Andrii Nakryiko <andrii@...nel.org>,
        Alexei Starovoitov <ast@...nel.org>,
        Network Development <netdev@...r.kernel.org>,
        Kernel Team <Kernel-team@...com>,
        Jakub Kicinski <kuba@...nel.org>,
        Toke Høiland-Jørgensen <toke@...hat.com>,
        Gal Pressman <gal@...dia.com>, Tariq Toukan <tariqt@...dia.com>
Subject: Re: [PATCH bpf-next v7 0/3] Add skb + xdp dynptrs

Hi,

I'm reviving this thread, following the discussion here:
https://lore.kernel.org/bpf/87fscjakba.fsf@toke.dk/

On 21/10/2022 4:19, Alexei Starovoitov wrote:
> On Thu, Oct 20, 2022 at 6:15 PM Joanne Koong <joannelkoong@...il.com> wrote:
>>
>> This patchset is the 2nd in the dynptr series. The 1st can be found here [0].
>>
>> This patchset adds skb and xdp type dynptrs, which have two main benefits for
>> packet parsing:
>>      * allowing operations on sizes that are not statically known at
>>        compile-time (eg variable-sized accesses).
>>      * more ergonomic and less brittle iteration through data (eg does not need
>>        manual if checking for being within bounds of data_end)
>>
>> When comparing the differences in runtime for packet parsing without dynptrs
>> vs. with dynptrs for the more simple cases, there is no noticeable difference.
>> For the more complex cases where lengths are non-statically known at compile
>> time, there can be a significant speed-up when using dynptrs (eg a 2x speed up
>> for cls redirection). Patch 3 contains more details as well as examples of how
>> to use skb and xdp dynptrs.
> 
> Before proceeding with this patchset I think we gotta resolve the
> issues with dynptr-s that Kumar found.

Just to make sure I'm following: The issues that are discussed here?
https://lore.kernel.org/all/CAP01T74icBDXOM=ckxYVPK90QLcU4n4VRBjON_+v74dQwJfZvw@mail.gmail.com/

What is the current status of dynptrs?
Any updates since October?
Do we have any agreement or a plan for this?

Regards,
Tariq