From: Harald Welte <[EMAIL PROTECTED]> Date: Sun, 10 Mar 2002 08:23:29 +0100 > One should never set IP_DF for ICMP packets. Well, I haven't heard of any rule (especially not in an RFC) about this - but I assume it's because somebody would then send an ICMP frag_needed in response to our ICMP error message - and we wouldn't know about which of our error message the frag_needed was about?
Yes, this is the reason. And my real impetus for the change was my seeing that the code stated "this matches what icmp.c does" when in fact it did not. Our ICMP code never will set IP_DF in an outgoing ICMP packet. See how the icmp_socket PMTU setting is initialized in net/ipv4/icmp.c to understand why.
