diff --git a/openbsc/src/ipaccess/ipaccess-proxy.c b/openbsc/src/ipaccess/ipaccess-proxy.c
index b4d17e2c7..21dc70c27 100644
--- a/openbsc/src/ipaccess/ipaccess-proxy.c
+++ b/openbsc/src/ipaccess/ipaccess-proxy.c
@@ -103,7 +103,7 @@ struct ipa_bts_conn {
 	uint16_t gprs_orig_port;
 	uint32_t gprs_orig_ip;
 
-	char *id_tags[0xff];
+	char *id_tags[256];
 	uint8_t *id_resp;
 	unsigned int id_resp_len;
 };
@@ -488,7 +488,7 @@ static int ipaccess_rcvmsg(struct ipa_proxy_conn *ipc, struct msgb *msg,
 				return 0;
 			}
 
-			if (trx_id > MAX_TRX) {
+			if (trx_id >= MAX_TRX) {
 				LOGP(DINP, LOGL_ERROR, "We don't support more "
 				     "than %u TRX\n", MAX_TRX);
 				return -EINVAL;