If we cache them, the kernel will reuse them, independently of whether forwarding is enabled or not. Which means that if forwarding is disabled on the input interface where the first routing request comes from, then that unreachable result will be cached and reused for other interfaces, even if forwarding is enabled on them. The opposite is also true.
This can be verified with two interfaces A and B and an output interface C, where B has forwarding enabled, but not A and trying ip route get $dst iif A from $src && ip route get $dst iif B from $src Signed-off-by: Nicolas Cavallari <[email protected]> Reviewed-by: Julian Anastasov <[email protected]> --- > Sorry Nicolas, this seems to have fallen on the floor. Could you please > resubmit your most uptodate version of this patch so I can apply it? Here you are. diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 2d4ae46..6a2155b 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1798,6 +1798,7 @@ local_input: no_route: RT_CACHE_STAT_INC(in_no_route); res.type = RTN_UNREACHABLE; + res.fi = NULL; goto local_input; /* -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
