sgsn: Don't attempt to delete GTP pdp ctx if GGSN was restarted
Scenario and behaviour before this commit:
- Received Echo Reply from GGSN has incremented RestartCounter
- func sgsn_ggsn_ctx_drop_all_pdp() is called to dettach all pdp ctx
from GGSN and request the MS to deact all related ctx.
- DEACT ACCEPT is received from MS, and then it tries to send DEL PDP CTX
to GGSN, expecting to receive a Confirmation and only then freeing the
pdp ctx.
The problem is that since the initial cause of triggering was a GGSN
restart, the GGSN doesn't know anything about that pdp ctx anymore, so
it's not useful sending it. We can instead dettach the GGSN and libgtp
ref at drop_all_pdp() time and then when we receive DEACT ACCEPT from MS
we can free the pdp ctx directly.
Change-Id: I1c74098e181552c218e152bf4ac5035cea770428
diff --git a/src/gprs/gprs_sgsn.c b/src/gprs/gprs_sgsn.c
index 35479fb..ef0cc23 100644
--- a/src/gprs/gprs_sgsn.c
+++ b/src/gprs/gprs_sgsn.c
@@ -444,7 +444,8 @@
/* Detach from MM context */
pdp_ctx_detach_mm_ctx(pdp);
- sgsn_delete_pdp_ctx(pdp);
+ if (pdp->ggsn)
+ sgsn_delete_pdp_ctx(pdp);
}
/*
@@ -479,8 +480,6 @@
lib->priv = NULL;
}
- if (pdp->destroy_ggsn)
- sgsn_ggsn_ctx_free(pdp->ggsn);
talloc_free(pdp);
}
@@ -702,9 +701,10 @@
static void drop_one_pdp(struct sgsn_pdp_ctx *pdp)
{
- if (pdp->mm->gmm_state == GMM_REGISTERED_NORMAL)
+ if (pdp->mm->gmm_state == GMM_REGISTERED_NORMAL) {
gsm48_tx_gsm_deact_pdp_req(pdp, GSM_CAUSE_NET_FAIL, true);
- else {
+ sgsn_ggsn_ctx_remove_pdp(pdp->ggsn, pdp);
+ } else {
/* FIXME: GPRS paging in case MS is SUSPENDED */
LOGPDPCTXP(LOGL_NOTICE, pdp, "Hard-dropping PDP ctx due to GGSN "
"recovery\n");
@@ -739,6 +739,13 @@
llist_del(&pdp->ggsn_list);
if (llist_empty(&ggc->pdp_list) && osmo_timer_pending(&ggc->echo_timer))
osmo_timer_del(&ggc->echo_timer);
+ if (pdp->destroy_ggsn)
+ sgsn_ggsn_ctx_free(pdp->ggsn);
+ pdp->ggsn = NULL;
+ /* Drop references to libgtp since the conn is down */
+ if (pdp->lib)
+ pdp_freepdp(pdp->lib);
+ pdp->lib = NULL;
}
void sgsn_update_subscriber_data(struct sgsn_mm_ctx *mmctx)