[Dnsmasq-discuss] Segfault in dnsmasq 2.72 compiled from source on CentOS6

[Matt Coddington]

Hi,
I am wanting to use the "statistics available as DNS queries in the .bind
TLD" feature of dnsmasq. The currently available RPM in the CentOS repo's
is 2.48, and that .bind TLD feature isn't available until 2.69.

I downloaded the source for 2.72 and am using the binary generated with a
straight up "make".

On a system with a reasonable amount of DNS traffic (it's an MTA sending a
couple thousand emails per day), the 2.72 binary segfaults usually in about
1-5 minutes (though once I had it run for a few hours before segfaulting).
When I run the stock CentOS 2.48 RPM version it does not segfault. I also
compiled my own 2.48 to see if maybe there was some sort of issue with my
compilation environment and that also has not segfaulted in over a day, so
this does seem to be an issue that is related to some difference between
2.48 and 2.72.

I captured a core file from one of the segfaults. I don't have a lot of
experience with that sort of debugging, but the stack trace seems pretty
huge to me - it is almost 35000 deep. Here is the last bit of it where it
finally gets into the dnsmasq code as opposed to system libraries:

#34784 0x000000000040b4d6 in whine_malloc (size=144) at util.c:258
#34785 0x0000000000413a68 in allocate_frec (now=1427863329,
    wait=0x7fff78f2d3ac, force=0) at forward.c:1946
#34786 get_new_frec (now=1427863329, wait=0x7fff78f2d3ac, force=0)
    at forward.c:2107
#34787 0x0000000000418e86 in set_dns_listeners (now=1427863329,
    set=0x7fff78f2d5e0, maxfdp=0x7fff78f2d6ac) at dnsmasq.c:1403
#34788 0x000000000041a909 in main (argc=<value optimized out>,
    argv=<value optimized out>) at dnsmasq.c:809

I'm happy to share the abrtd dump directory w/the core file and other info
if that would be helpful - just let me know how you'd like to receive it.

thanks!
matt
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