Re: Does ICMP_FRAG_NEEDED automatically update the routing cache?

Hi!

On Fri, Feb 14, 2014 at 02:36:48PM +0000, David Howells wrote:

Am I reading the ipv4 code right?  If a UDP packet we send results in an
ICMP_FRAG_NEEDED packet being received, the cached routing information for the
peer will automatically be updated by __udp4_lib_err()?

A next hop exception will be generated (or reused) which stores the path
mtu towards that target, yes (there is no more routing cache).

Prior to that a validation check happens if the socket really exists (this is
e.g. needed to identify the namespace or routing table the update should occur
on).

And something similar in __udp6_lib_err()?

Exactly.

Greetings,

  Hannes