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From: David Ahern <dsahern@gmail.com>
To: mastertheknife <mastertheknife@gmail.com>
Cc: netdev@vger.kernel.org
Subject: Re: PMTUD broken inside network namespace with multipath routing
Date: Tue, 1 Sep 2020 18:42:10 -0600	[thread overview]
Message-ID: <2f0e9d12-1780-cd1f-891d-940274f9105d@gmail.com> (raw)
In-Reply-To: <CANXY5yLXpS+YYVeUPGok7R=4cm2AEAoM1zR_sd6YSKqCJPGLOg@mail.gmail.com>

On 9/1/20 4:40 AM, mastertheknife wrote:
> 
> P.S: while reading the relevant code in the kernel, i think i spotted
> some mistake in net/ipv4/route.c, in function "update_or_create_fnhe".
> It looks like it loops over all the exceptions for the nexthop entry,
> but always overwriting the first (and only) entry, so effectively only
> 1 exception can exist per nexthop entry.
> Line 678:
> "if (fnhe) {"
> Should probably be:
> "if (fnhe && fnhe->fnhe_daddr == daddr) {"
> 

Right above that line is:

        for (fnhe = rcu_dereference(hash->chain); fnhe;
             fnhe = rcu_dereference(fnhe->fnhe_next)) {
                if (fnhe->fnhe_daddr == daddr)
                        break;
                depth++;
        }

so fnhe is set based on daddr match.

      parent reply	other threads:[~2020-09-02  0:42 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-08-03 11:14 mastertheknife
2020-08-03 13:32 ` David Ahern
2020-08-03 14:24   ` mastertheknife
2020-08-03 15:38     ` David Ahern
2020-08-03 18:39       ` mastertheknife
2020-08-10 22:13         ` David Ahern
2020-08-12 12:37           ` mastertheknife
2020-08-12 19:21             ` David Ahern
2020-08-14  7:08               ` mastertheknife
2020-09-01 10:40                 ` mastertheknife
2020-09-01 10:44                   ` mastertheknife
2020-09-02  0:42                   ` David Ahern [this message]

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