double-free bug and a question

[Patrick McHardy]

jmzhou.ml at gmail.com wrote:
> Apology if this has been reported. Here's the way to reproduce the crash:
> 
> # iptables -A INPUT --protocol udp -m multiport --dports 65530:65535 -m
> multiport --sport 53:67 -j ACCEPT
> *** glibc detected *** double free or corruption (!prev): 0x08055160 ***
> Abort (core dumped)
> 
> # iptables -A INPUT --protocol udp -m multiport --dports 65530:65535 -m
> multiport --sports 53:67 -j ACCEPT
> Bad argument `53:67'
> Try `iptables -h' or 'iptables --help' for more information.
> 
> $ iptables --version
> iptables v1.3.5
> 
> 
> What I want to do is to define multiple ports for both source and
> destination in a single iptables rule. Is there any way to do it?
> Thanks!

Read the help for multiport, the ports are given as comma-seperated
list. For simple ranges you don't need multiport. For source and
destination you must only specify "-m multiport" once.

I have no idea where the crash comes from (works fine here). Please
try to get a backtrace by running the command in gdb:

gdb iptables

(gdb) run -A INPUT ...
<crash>
(gdb) backtrace