diff --git a/openbsc/include/openbsc/gsm_data.h b/openbsc/include/openbsc/gsm_data.h
index ac04265..03794c2 100644
--- a/openbsc/include/openbsc/gsm_data.h
+++ b/openbsc/include/openbsc/gsm_data.h
@@ -100,6 +100,7 @@
 #define msgb_bvci(__x)		OBSC_MSGB_CB(__x)->bvci
 #define msgb_gmmh(__x)		(__x)->l3h
 #define msgb_bssgph(__x)	OBSC_MSGB_CB(__x)->bssgph
+#define msgb_bssgp_len(__x)	((__x)->tail - (uint8_t *)msgb_bssgph(__x))
 #define msgb_bcid(__x)		OBSC_MSGB_CB(__x)->bssgp_cell_id
 #define msgb_llch(__x)		OBSC_MSGB_CB(__x)->llch
 
diff --git a/openbsc/src/gprs_bssgp.c b/openbsc/src/gprs_bssgp.c
index aceedb5..554738b 100644
--- a/openbsc/src/gprs_bssgp.c
+++ b/openbsc/src/gprs_bssgp.c
@@ -200,7 +200,7 @@
 	}
 	if (orig_msg)
 		msgb_tvlv_put(msg, BSSGP_IE_PDU_IN_ERROR,
-			      msgb_l3len(orig_msg), msgb_bssgph(orig_msg));
+			      msgb_bssgp_len(orig_msg), msgb_bssgph(orig_msg));
 
 	return gprs_ns_sendmsg(bssgp_nsi, msg);
 }
@@ -257,7 +257,7 @@
 static int bssgp_rx_ul_ud(struct msgb *msg)
 {
 	struct bssgp_ud_hdr *budh = (struct bssgp_ud_hdr *) msgb_bssgph(msg);
-	int data_len = msgb_l3len(msg) - sizeof(*budh);
+	int data_len = msgb_bssgp_len(msg) - sizeof(*budh);
 	struct tlv_parsed tp;
 	int rc;
 
@@ -285,7 +285,7 @@
 {
 	struct bssgp_normal_hdr *bgph =
 			(struct bssgp_normal_hdr *) msgb_bssgph(msg);
-	int data_len = msgb_l3len(msg) - sizeof(*bgph);
+	int data_len = msgb_bssgp_len(msg) - sizeof(*bgph);
 	struct tlv_parsed tp;
 	int rc;
 
@@ -307,7 +307,7 @@
 {
 	struct bssgp_normal_hdr *bgph =
 			(struct bssgp_normal_hdr *) msgb_bssgph(msg);
-	int data_len = msgb_l3len(msg) - sizeof(*bgph);
+	int data_len = msgb_bssgp_len(msg) - sizeof(*bgph);
 	struct tlv_parsed tp;
 	int rc;
 
@@ -352,7 +352,7 @@
 			(struct bssgp_normal_hdr *) msgb_bssgph(msg);
 	struct tlv_parsed tp;
 	uint8_t pdu_type = bgph->pdu_type;
-	int data_len = msgb_l3len(msg) - sizeof(*bgph);
+	int data_len = msgb_bssgp_len(msg) - sizeof(*bgph);
 	uint16_t bvci;	/* PTP BVCI */
 	uint16_t ns_bvci = msgb_bvci(msg);
 	int rc = 0;