netdev - Re: Massive hash collisions on FIB

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <d1d6fd2c-c631-44a0-9962-c482540b3847@orange.com>
Date: Wed, 25 Sep 2024 21:06:44 +0200
From: Alexandre Ferrieux <alexandre.ferrieux@...il.com>
To: Eric Dumazet <edumazet@...gle.com>
Cc: Simon Horman <horms@...nel.org>,
 Przemek Kitszel <przemyslaw.kitszel@...el.com>, nicolas.dichtel@...nd.com,
 netdev@...r.kernel.org
Subject: Re: Massive hash collisions on FIB

On 24/09/2024 19:18, Alexandre Ferrieux wrote:
> 
> I see you did the work for the two other hashes (laddr and devindex).
> I tried to inject the dispersion the same way as you did, just before the final
> scrambling. Is this what you'd do ?
> 
> diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
Doing this, I discovered with surprise that the job was already done in IPv6, as
inet6_addr_hash() uses net_hash_mix() too. Which leads to the question: why are
the IPv4 and IPv6 FIB-exact-lookup implementations different/duplicated ?