tree 3d87c7c8e7e58cf438cab8905150a77dfaf92a7f
parent ac687be468e66d770c94af185da0bf39bfe1e94a
author Harald Welte <laforge@gnumonks.org> 1318783856 +0200
committer Harald Welte <laforge@gnumonks.org> 1318784310 +0200

GPRS GMM: Send LLGMM-RESET.req when talking to unknown MS

In case a MS (of which we have no MM context) sends us anything but a
GMM ATTACH REQUEST, we need to send it a LLC XID RESET (by means of
issuing LLGMM-RESET.req).  Otherwise the phone will expect us to send a
specific unacknowledged sequence number that we don't know.

Thanks to Holger for pointing this bug out to me.

It seems to commonly occur when a MS is doing network re-selection and
(erroneously) sends a RA UPD REQ instead of an ATTACH REQ.  The RA UPD
REJ that we sent was never seen by the GMM entity in the MS, as the LLC
entity discarded it due to sequence number mis-match.