Milter-greylist

On Fri, Mar 14, 2008 at 09:39:32PM -0000, reschauzier wrote:
> See below. Let me know if you need additional info.
> 
> Rudy.
> 
> Core was generated by `/usr/bin/milter-greylist -P
> /var/milter-greylist/milter-greylist.pid -p /var/mi'.
> Program terminated with signal 11, Segmentation fault.
> #0  0x00c75f6c in free () from /lib/libc.so.6
> (gdb)     thread apply all bt full
> 
[..]
> 
> Thread 1 (process 13734):
> #0  0x00c75f6c in free () from /lib/libc.so.6
> No symbol table info available.
> #1  0x0014ae74 in __res_ndestroy () from /usr/lib/libbind.so.4
> No symbol table info available.
> #2  0x0014b7ee in __res_vinit () from /usr/lib/libbind.so.4
> No symbol table info available.
> #3  0x0014c4f5 in __res_ninit () from /usr/lib/libbind.so.4
> No symbol table info available.
> #4  0x00a71f9c in SPF_dns_resolv_new () from /usr/lib/libspf2.so.2
> No symbol table info available.
> #5  0x00a7003f in SPF_dns_lookup () from /usr/lib/libspf2.so.2
> No symbol table info available.
> #6  0x00a709b2 in SPF_dns_get_client_dom () from /usr/lib/libspf2.so.2
> ---Type <return> to continue, or q <return> to quit---
> No symbol table info available.
> #7  0x00a7003f in SPF_dns_lookup () from /usr/lib/libspf2.so.2
> No symbol table info available.
> #8  0x00a7916f in SPF_server_get_record () from /usr/lib/libspf2.so.2
> No symbol table info available.
> #9  0x00a785c3 in SPF_request_query_mailfrom () from /usr/lib/libspf2.so.2
> No symbol table info available.
[..]

This seems really to be the known res_ninit() issue (see my previous
posting): The caller have to provide a private data segment, for
subsequent resolver calls. If this memory area will be not cleared, some
resolver-library versions are assuming non-zero values of the data
structure as pointer to not returned malloc'd memory from the past - but
this assumption is wrong if the malloc'd memory was not wiped with zeros
and garbage is in the memory segment. Trying to apply free on such a
surious pointer leads to a segmentation fault (sooner or later).

Hope this helps.

Johann K.