[op5-users] Merlin crashed on me?

[Andreas Ericsson]

Frater, Greg J wrote:
> About 10 minutes after I installed Merlin the following appeared on my
> console, what does this mean?
> 
> 
>  *** glibc detected *** /usr/local/nagios/merlin/merlind: free():
> invalid size: 0x00007fff43ca2830 ***

This.

> ======= Backtrace: =========
> /lib64/libc.so.6[0x3613a71ce2]
> /lib64/libc.so.6(cfree+0x8c)[0x3613a7590c]
> /usr/local/nagios/merlin/merlind[0x405c0a]
> /usr/local/nagios/merlin/merlind[0x403977]
> /lib64/libc.so.6(__libc_start_main+0xf4)[0x3613a1d974]
> /usr/local/nagios/merlin/merlind[0x4021c9]
> ======= Memory map: ========
> 00400000-0040d000 r-xp 00000000 fd:00 6096222
> /usr/local/nagios/merlin/merlind
> 0060d000-0060e000 rw-p 0000d000 fd:00 6096222
> /usr/local/nagios/merlin/merlind
> 088d9000-08917000 rw-p 088d9000 00:00 0
> [heap]
> 7fff43c96000-7fff43cab000 rw-p 7ffffffea000 00:00 0
> [stack]

And this. Combined, it means Merlin tried to free() a stack-allocated
pointer (I think), or that there is a stack overflow somewhere which
caused Merlin to overwrite a short bit of memory in glibc's memory
allocator with an address to the stack. It could happen due to too
deep recursion, and there's one such place in Merlin which I've been
meaning to clean up for some time. Looks like the time to actually
do that has finally come.

Thanks for reporting this. It's likely you won't run into this
again for quite some time, but please let me know if this becomes a
frequent error, and especially if you're using the latest code from
merlin.git.

-- 
Andreas Ericsson                   andreas.ericsson at op5.se
OP5 AB                             www.op5.se
Tel: +46 8-230225                  Fax: +46 8-230231

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