Osmo-nitb v_0.13.0.48-9e22 broke compatibility with Nokia InSite

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Sipos Csaba dchardware at gmail.com
Thu Aug 1 23:41:14 UTC 2013


Hey Holger,

After placing some markers into the code, I have found the part which
is responsible for proper close of the OML connection:

lapd_sap_stop(ts->lapd, link->tei, link->sapi);

which is called properly by the Nokia related code, after the ACK got
received for the RESET_REQ. The lapd connection closes as it should:

Fri Aug  2 01:10:16 2013 <0018> input/lapd.c:513 LAPD DL-RELEASE request TEI=1 SAPI=62
Fri Aug  2 01:10:16 2013 <0018> lapd_core.c:2183 Message DL-RELEASE-REQUEST received in state LAPD_STATE_MF_EST
Fri Aug  2 01:10:16 2013 <0018> lapd_core.c:2024 perform local release
Fri Aug  2 01:10:16 2013 <0018> lapd_core.c:229 new state LAPD_STATE_MF_EST -> LAPD_STATE_IDLE
Fri Aug  2 01:10:16 2013 <0018> lapd_core.c:222 stop T203
Fri Aug  2 01:10:16 2013 <0018> input/lapd.c:628 LAPD DL-RELEASE confirm TEI=1 SAPI=62

Now OML lapd connection is closed,
but for some unkown reason lapd_core.c still try to process the
received lapd messages for an already closed connection, which causes
the segfault:

Fri Aug  2 01:10:16 2013 <0018> lapd_core.c:1781 lapd_send_i() called from line 1615
Segmentation fault (core dumped)

And this is not because the Nokia related code tries to send something
when the lapd connection is closed. From the above log, it is clear
that the LAPD connection got terminated as it should, so it seems this is a problem with
lapd_core.c in general, that for an already closed connection, if
something got received on the OML timeslot, lapd_core.c tries to
process it. And this behavior leads to the segfault.

This is normal, that lapd_core.c tries to process data related to an
already closed connection?

BR,
Csaba





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