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Subject2.2.x kernels missend odd-sized ICMP packets
I've noticed something exceedingly strange. 2.2.x kernels all seem to send
out odd sized ICMP packets improperly.

root@kite:/home/joey/prog>ping -qs 11 localhost
PING localhost (127.0.0.1): 11 data bytes

--- localhost ping statistics ---
26 packets transmitted, 0 packets received, 100% packet loss
Compare to:

root@kite:/home/joey/prog>ping -qs 10 localhost
PING localhost (127.0.0.1): 10 data bytes

--- localhost ping statistics ---
5 packets transmitted, 5 packets received, 0% packet loss
Or to:

root@kite:/home/joey/prog>ping -qs 12 localhost
PING localhost (127.0.0.1): 12 data bytes

--- localhost ping statistics ---
5 packets transmitted, 5 packets received, 0% packet loss
I wrote a quick test program:

#!/usr/bin/perl
for $c (1..1000) {
$p=ping -c 1 -s $c $ARGV[0];
($n)=$p=~m/ (\d+)% packet loss/;
print "packet size $c: $n% loss\n";
}
The results look like this:

packet size 1: 0% loss
packet size 2: 0% loss
packet size 3: 0% loss
packet size 4: 0% loss
packet size 5: 0% loss
packet size 6: 0% loss
packet size 7: 0% loss
packet size 8: 0% loss
packet size 9: 0% loss
packet size 10: 0% loss
packet size 11: 100% loss
packet size 12: 0% loss
packet size 13: 100% loss
packet size 14: 0% loss
packet size 15: 100% loss
packet size 16: 0% loss
packet size 17: 100% loss
packet size 18: 0% loss
packet size 19: 100% loss
packet size 20: 0% loss
packet size 21: 100% loss
packet size 22: 0% loss
packet size 23: 100% loss
packet size 24: 0% loss
packet size 25: 100% loss
packet size 26: 0% loss
packet size 27: 100% loss
packet size 28: 0% loss
packet size 29: 100% loss
packet size 30: 0% loss

This isn't limited to pinging localhost. In fact, it doesn't seem to matter
where I ping to, I see the same pattern of packet losses. Some friends tried
it with other kernel versions than the 2.2.5 I am using. Everything in the
2.2.x series seems to have the problem. 2.2.0-pre6 seems fine.

--
see shy jo

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