tree 5a9dd0d210b35577414f5d9dfc40ce0a9f1ae566
parent af2e9b349cfe1ccf4a19b7bf21c70ffc9d9191ed
author Daniel Willmann <dwillmann@sysmocom.de> 1637874296 +0100
committer Daniel Willmann <dwillmann@sysmocom.de> 1637874296 +0100

gbproxy: Fix crash when FLUSH_LL_ACK does not contain a BVCI IE

The BVCI IE is listed as conditional and is only included if the flush
action indicates that LLC-PDUs are transferred. (3GPP TS 48.018 Ch.
10.4.2).

The code in gbprox_rx_sig_from_bss unconditionally tries to get a BVCI
from a FLUSH_LL message which could result in a segfault if no such IE
is included. Routing towards the SGSN can happen simply based on TLLI (for pooling)
since there is only one signalling BVC towards the SGSN.

Related: OS#5332
Change-Id: I659f9c925bb38b8cf2348b84b976142d8d4693f7