On Thursday 2008-11-27 17:15, Patrick McHardy wrote:

   netfilter: nf_nat: remove warn_if_extra_mangle
   
   In net/ipv4/netfilter/nf_nat_rule.c, the function warn_if_extra_mangle was added
   in commit 5b1158e909ecbe1a052203e0d8df15633f829930 (2006-12-02). I have a DNAT
   target in the OUTPUT chain than changes connections with dst 2.0.0.1 to another
   address which I'll substitute with 66.102.9.99 below.
   
   On every boot I get the following message:
   [  146.252505] NAT: no longer support implicit source local NAT
   [  146.252517] NAT: packet src 66.102.9.99 -> dst 2.0.0.1
   
   As far as I can tell from reading the function doing this, it should warn if the
   source IP for the route to 66.102.9.99 is different from 2.0.0.1 but that is not
   the case. It doesn't make sense to check the DNAT target against the local route
   source.
   
   Either the function should be changed to correctly check the route, or it should
   be removed entirely as it's been nearly 2 years since it was added.

Why did implicit local SNAT even go? It was kind of a neat way to
be able to issue `socat - tcp-client:localhost:1234` and have
it redirected elsewhere on the net.