diff --git a/astlpc.c b/astlpc.c
index 5218c92..616ed1d 100644
--- a/astlpc.c
+++ b/astlpc.c
@@ -178,12 +178,12 @@
 		return;
 	}
 
-	if (len > MCTP_MTU + sizeof(struct mctp_hdr)) {
+	if (len > astlpc->binding.pkt_size) {
 		mctp_prwarn("invalid RX len 0x%x", len);
 		return;
 	}
 
-	pkt = mctp_pktbuf_alloc(len);
+	pkt = mctp_pktbuf_alloc(&astlpc->binding, len);
 	if (!pkt)
 		goto out_complete;
 
@@ -335,6 +335,8 @@
 	astlpc->binding.name = "astlpc";
 	astlpc->binding.version = 1;
 	astlpc->binding.tx = mctp_binding_astlpc_tx;
+	astlpc->binding.pkt_size = MCTP_BMTU;
+	astlpc->binding.pkt_pad = 0;
 
 	rc = mctp_astlpc_init_lpc(astlpc);
 	if (rc) {