Bug #2499
Updated by neels over 6 years ago
Take this osmo-msc config, I have an ASP with remote-ip defined, but no AS:
<pre>
network
network country code 1
mobile network code 1
short name OsmoMSC
long name OsmoMSC
auth policy closed
location updating reject cause 13
encryption a5 0
rrlp mode none
mm info 1
cs7 instance 0
point-code 0.23.1
asp asp-clnt-OsmoMSC-A-Iu 2905 0 m3ua
! where to reach the STP:
remote-ip 10.23.24.1
msc
cs7-instance-a 0
cs7-instance-iu 0
mgcpgw remote-ip 10.23.24.1
assign-tmsi
</pre>
What happens when osmo-msc starts is:
- a new AS is created because none exists yet.
- for that AS, no ASP is defined, so one is created. But this by doing
osmo_ss7_asp_find_or_create(ss7, asp_name, default_remote_port,
default_local_port, prot);
Because I have created in the VTY an ASP that has exactly the name that is
autogenerated, instead of creating a fresh one, the
osmo_ss7_asp_find_or_create() returns exactly that one the VTY created.
- next, the code does:
asp->cfg.remote.host = default_remote_ip [...];
i.e. it silently overwrites the IP address I have configured in the VTY.
Writing the config back results in
<pre>
cs7 instance 0
point-code 0.23.1
asp asp-clnt-OsmoMSC-A-Iu 2905 0 m3ua
remote-ip 127.0.0.1
as as-clnt-OsmoMSC-A-Iu m3ua
asp asp-clnt-OsmoMSC-A-Iu
routing-key 0 0.23.1
</pre>
(i.e. with a different ASP remote-ip than originally)
What the user clearly requested is dropped on the floor without any warning.
Also the previous value in asp->cfg.remote.host is un-freed.
Of course this only happens when the ASP's name exactly matches the default
name, but when we use config generated by 'show running-config' or 'write file'
and tweak that, this is actually a quite common case.
