netdev - Re: Fw: [Bug 199995] New: Ramdomly sent TCP Reset from Kernel with bonding mode "brodcast"

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] [day] [month] [year] [list]

Message-ID: <b5d2663f-4656-b396-c970-11750acb6b1c@gmail.com>
Date:   Fri, 8 Jun 2018 14:53:22 -0700
From:   Eric Dumazet <eric.dumazet@...il.com>
To:     Eric Dumazet <eric.dumazet@...il.com>,
        Michal Kubecek <mkubecek@...e.cz>,
        Stephen Hemminger <stephen@...workplumber.org>
Cc:     netdev@...r.kernel.org
Subject: Re: Fw: [Bug 199995] New: Ramdomly sent TCP Reset from Kernel with
 bonding mode "brodcast"



On 06/08/2018 02:38 PM, Eric Dumazet wrote:
> 
> 
> On 06/08/2018 02:04 PM, Michal Kubecek wrote:

>>
>> However, the lockless listener was introduced in 4.4 so it's not clear
>> why reporter started encountering this after an upgrade from 4.13 to
>> 4.15.
> 
> Yes, I do not buy this at all.
> 
> If two identical SYN are received by two cpus, we should create one SYN_RECV and send
> two SYNACK.
> 
> But it is a bit hard to test this :/
> 
> I will take a look, thanks.


Oh well, this is not done as I thought, this needs a fix, I will work on this.

reqsk_queue_hash_req() calls inet_ehash_insert() without making sure that the same 4-tuple
is not already there.

Do not worry, we will keep the listener lockless :)