On 11/25/2010 07:32 PM, dotnetdub wrote:
Hi Marius,
I hope this is what your after!
(gdb) add-symbol-file /lib/kamailio/modules/topoh.so
0xb7004000+0x00001d30
add symbol table from file "/lib/kamailio/modules/topoh.so" at
.text_addr = 0xb7005d30
(y or n) y
Reading symbols from /lib/kamailio/modules/topoh.so...done.
(gdb) x/s 0xb70070d9
0xb70070d9 <th_skip_msg+9>: <Address 0xb70070d9 out of bounds>
(gdb) info registers
Yes I think it is
Looking at the debug messages I see the CSeq is wrong.
But :
int th_skip_msg(sip_msg_t *msg)
{
if((get_cseq(msg)->method_id)&(METHOD_REGISTER|METHOD_PUBLISH))
return 1;
return 0;
}
As the cseq is wrong the get_cseq macro probably returns a NULL
Pointer who gets dereferenced (BANG the crash). Any other Ideas ?!
The patch is trivial ( if(!get_cseq(msg))) parse_cseq(....) )
something in this line. Daniel, What do you think ?
Marius
Thanks Marius.
Glad that we were able to find the issue.
Are you able to test a patch if a provide one to you? I wanted to wait
for Daniel's opinion as I have no way of testing it. If you have a dump
of the attack traffic or you can generate more with bad CSEQ (as from
the message log you provided) you can test the patch against your cfg
and see if it still crashes(hope not). In my opinion the crash should be
deterministic. You will find the trivial patch attached. If you can test
it and it works I will push it to upstream (also to 3.0 branch). Keep in
mind that other probles might appear as well during the processing of
the SIP messages. If a core does appear please retry the steps in the
previous mail with the new core and .so offset.
Apply the patch with the patch utility (copy to the modules/topoh and
run patch < patch) . I await some feedback :)
Marius
Regards
Brian