Hi Simon,

On Sun, Jun 28, 2009 at 5:43 PM, Simon Horman[off-list ref] wrote:

On Wed, Jun 24, 2009 at 03:22:32PM +0200, Julius Volz wrote:

quoted

Add handling of incoming ICMPv6 Packet Too Big messages. This message
is received when a realserver sends a packet >PMTU to the client. The
hop on this path with insufficient MTU will generate an ICMPv6 Packet
Too Big message back to the VIP. The LVS server receives this message,
but the call to the function handling this has been missing. Thus, IPVS
fails to forward the message to the real server, which then does not
adjust the path MTU. This patch adds the missing call to
ip_vs_in_icmp_v6() in ip_vs_in() to handle this situation.

Thanks to Rob Gallagher from HEAnet for reporting this issue and for
testing this patch in production (with direct routing mode).

Signed-off-by: Julius Volz <redacted>
Tested-by: Rob Gallagher <redacted>

Hi Julius, Hi Rob,

this seems reasonable to me, although it seems that the following
code is common. I wonder if its repetition could be removed.

                       if (related)
                               return verdict;
                       ip_vs_fill_iphdr(af, skb_network_header(skb), &iph);

I agree, though I see no "nice" way to remove this duplication
considering the ifs and #ifdefs around this. You could move the
related and verdict variables to the top of the function and then
recheck afterwards whether one of these ICMP-handling branches was
entered and put the common code in there. But this seems more
cumbersome to me than repeating the code. Maybe you see a nicer way?
Btw., exactly this structure already exists in ip_vs_out(), which is
why I adopted it like this for ip_vs_in().

Cheers,
Julius