diff --git a/openbsc/src/gprs/sgsn_libgtp.c b/openbsc/src/gprs/sgsn_libgtp.c
index 862dd40..df392b9 100644
--- a/openbsc/src/gprs/sgsn_libgtp.c
+++ b/openbsc/src/gprs/sgsn_libgtp.c
@@ -445,6 +445,7 @@
 
 	/* Start GTP re-transmission timer */
 	sgi->gtp_timer.cb = sgsn_gtp_tmr_cb;
+	sgi->gtp_timer.data = sgi;
 	sgsn_gtp_tmr_start(sgi);
 
 	/* Register callbackcs with libgtp */