Re: [PATCH mptcp-net] mptcp: consolidate suboption status.

[Matthieu Baerts <matttbe@kernel.org>]

Hi Paolo,

On 16/01/2025 21:25, Matthieu Baerts wrote:
> Hi Paolo,
> 
> On 15/01/2025 22:12, Paolo Abeni wrote:
>> MPTCP maintains the received sub-options status is the bitmask carrying
>> the received suboptions and in several bitfields carrying per suboption
>> additional info.
>>
>> Zeroing the bitmask before parsing is not enough to ensure a consistent
>> status, and the MPTCP code has to additionally clear some bitfiled
>> depending on the actually parsed suboption.
>>
>> The above schema is fragile, and syzbot menaged to trigger a path where
>> a relevant bitfield is not cleared/initialized:
> 
> (...)
> 
>> The current schema is too fragile; address the issue grouping all the
>> state-related data together and clearing the whole group instead of
>> just the bitmask. This also cleans-up the code a bit, as there is no
>> need anymore to individually clear "random" bitfield in a couple of
>> places.
> 
> Good catch, and now cleaner!
> 
> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>

Now in our tree (fixes for -net) (without 2 spelling mistakes spotted by
checkpatch.pl --codespell):

New patches for t/upstream-net and t/upstream:
- 818bca988793: mptcp: consolidate suboption status
- Results: 05dbdeb0df9f..1b76b0bd2522 (export-net)
- Results: 23e469da2e50..2a6dfa001e66 (export)

Tests are now in progress:

- export-net:
https://github.com/multipath-tcp/mptcp_net-next/commit/6522a18009fb2dd2de6badbd6f3a75094ef56c5e/checks
- export:
https://github.com/multipath-tcp/mptcp_net-next/commit/8e6fd4818b81ecebcca1a3eb44a2927845471434/checks

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.