netdev - Re: [PATCH net] udp: fix l4 hash after reconnect

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: <b46a7757-f311-4656-a114-68381d9856e3@redhat.com>
Date: Fri, 6 Dec 2024 17:23:59 +0100
From: Paolo Abeni <pabeni@...hat.com>
To: Eric Dumazet <edumazet@...gle.com>
Cc: netdev@...r.kernel.org, "David S. Miller" <davem@...emloft.net>,
 David Ahern <dsahern@...nel.org>, Jakub Kicinski <kuba@...nel.org>,
 Simon Horman <horms@...nel.org>, Fred Chen <fred.cc@...baba-inc.com>,
 Cambda Zhu <cambda@...ux.alibaba.com>, Willem de Bruijn
 <willemb@...gle.com>, Philo Lu <lulie@...ux.alibaba.com>,
 Stefano Brivio <sbrivio@...hat.com>
Subject: Re: [PATCH net] udp: fix l4 hash after reconnect

On 12/6/24 17:01, Eric Dumazet wrote:
> On Fri, Dec 6, 2024 at 4:57 PM Eric Dumazet <edumazet@...gle.com> wrote:
>> On Fri, Dec 6, 2024 at 4:50 PM Paolo Abeni <pabeni@...hat.com> wrote:
>>>
>>> After the blamed commit below, udp_rehash() is supposed to be called
>>> with both local and remote addresses set.
>>>
>>> Currently that is already the case for IPv6 sockets, but for IPv4 the
>>> destination address is updated after rehashing.
>>>
>>> Address the issue moving the destination address and port initialization
>>> before rehashing.
>>>
>>> Fixes: 1b29a730ef8b ("ipv6/udp: Add 4-tuple hash for connected socket")
>>> Signed-off-by: Paolo Abeni <pabeni@...hat.com>
>>
>> Nice catch, thanks !
>>
>> Reviewed-by: Eric Dumazet <edumazet@...gle.com>
> 
> BTW, it seems that udp_lib_rehash() does the udp_rehash4()
> only if the hash2 has changed.

Oh, you are right, that requires a separate fix.

@Philo: could you please have a look at that? basically you need to
check separately for hash2 and hash4 changes.

Thanks!

Paolo