sgsn: Don't allow mmctx == NULL in sgsn_update_subscriber_data

Currently, sgsn_update_subscriber_data can be called with mmctx ==
NULL and will find and associate the right context (if present) based
on the subscriber's IMSI. This will not happen in regular use
any more, since sgsn_update_subscriber_data will only be called when
subscribers are used (auth mode 'remote') and in this case
gprs_subscr_get_or_create_by_mmctx will already be called by
sgsn_auth_request. Therefore, MM context and subscriber are always
associated except for some test cases and experimental VTY usage.
The current implementation of sgsn_update_subscriber_data also causes
additional complexity for the deletion on MM contexts to avoid a
ipossible double-free MM contexts.

This commit removes the MM context <-> subscriber association code
from sgsn_update_subscriber_data. That function must always be called
with mmctx != NULL, now. To avoid problems with VTY and test usage,
the calling subscriber function now only call
sgsn_update_subscriber_data when mmctx != NULL, since the purpose of
that function is to update that state of an existing MM context after
subscriber data has been changed.

Sponsored-by: On-Waves ehf

1 files changed, 1 insertions, 2 deletions

diff --git a/openbsc/include/openbsc/gprs_sgsn.h b/openbsc/include/openbsc/gprs_sgsn.h
index 533117a74..ce73e0189 100644
--- a/openbsc/include/openbsc/gprs_sgsn.h
+++ b/openbsc/include/openbsc/gprs_sgsn.h
@@ -339,8 +339,7 @@ int gprs_subscr_query_auth_info(struct gsm_subscriber *subscr);
 int gprs_subscr_location_update(struct gsm_subscriber *subscr);
 
 /* Called on subscriber data updates */
-void sgsn_update_subscriber_data(struct sgsn_mm_ctx *mmctx,
-				 struct gsm_subscriber *subscr);
+void sgsn_update_subscriber_data(struct sgsn_mm_ctx *mmctx);
 
 int gprs_sndcp_vty_init(void);
 struct sgsn_instance;