GPRS LLC: fix segfault when transmitting downlink unit-data without mmctx
diff --git a/openbsc/src/gprs/gprs_llc.c b/openbsc/src/gprs/gprs_llc.c
index c705c87..6244d18 100644
--- a/openbsc/src/gprs/gprs_llc.c
+++ b/openbsc/src/gprs/gprs_llc.c
@@ -43,11 +43,16 @@
struct bssgp_dl_ud_par dup;
const uint8_t qos_profile_default[3] = { 0x00, 0x00, 0x20 };
- dup.tlli = NULL;
- dup.imsi = mmctx->imsi;
- dup.drx_parms = mmctx->drx_parms;
- dup.ms_ra_cap.len = mmctx->ms_radio_access_capa.len;
- dup.ms_ra_cap.v = mmctx->ms_radio_access_capa.buf;
+ memset(&dup, 0, sizeof(dup));
+ /* before we have received some identity from the MS, we might
+ * not yet have a MMC context (e.g. XID negotiation of primarly
+ * LLC connection fro GMM sapi). */
+ if (mmctx) {
+ dup.imsi = mmctx->imsi;
+ dup.drx_parms = mmctx->drx_parms;
+ dup.ms_ra_cap.len = mmctx->ms_radio_access_capa.len;
+ dup.ms_ra_cap.v = mmctx->ms_radio_access_capa.buf;
+ }
memcpy(&dup.qos_profile, qos_profile_default,
sizeof(qos_profile_default));