Subject: Re: [PATCH] [IPv4] Reply net unreachable ICMP message

From: Jarek Poplawski <[email-masked]>
Date: Thu, 6 Dec 2007 09:47:33 +0100

On 06-12-2007 09:14, Mitsuru Chinen wrote:
> On Thu, 6 Dec 2007 08:49:47 +0100
> Jarek Poplawski <[email-masked]> wrote:
> 
>> On 06-12-2007 07:31, Mitsuru Chinen wrote:
>>> IPv4 stack doesn't reply any ICMP destination unreachable message
>>> with net unreachable code when IP detagrams are being discarded
>>> because of no route could be found in the forwarding path.
>>> Incidentally, IPv6 stack replies such ICMPv6 message in the similar
>>> situation.
...
>> This patch seems to be wrong. It overrides err codes from
>> fib_lookup, where such decisions should be made.
> 
> fib_lookup() replies -ESRCH in this situation.
> It is necessary to override the variable by the suitable error
> number like the code under e_hostunreach label.

Probably I miss something, but I can't see how can you be sure it's
only -ESRCH possible here? Isn't opt->action() in fib_rules_lookup()
supposed to return this -ENETUNREACH when needed?

Jarek P.