diff --git a/src/connection.c b/src/connection.c
index 2e081d8ac..2fa2f05f8 100644
--- a/src/connection.c
+++ b/src/connection.c
@@ -1039,7 +1039,7 @@ int make_proxy_line_v2(char *buf, int buf_len, struct server *srv, struct connec
 	if (conn_get_alpn(remote, &value, &value_len)) {
 		if ((buf_len - ret) < sizeof(struct tlv))
 			return 0;
-		ret += make_tlv(&buf[ret], buf_len, PP2_TYPE_ALPN, value_len, value);
+		ret += make_tlv(&buf[ret], (buf_len - ret), PP2_TYPE_ALPN, value_len, value);
 	}
 
 #ifdef USE_OPENSSL
@@ -1081,7 +1081,7 @@ int make_proxy_line_v2(char *buf, int buf_len, struct server *srv, struct connec
 	if (remote && (remote->proxy_netns)) {
 		if ((buf_len - ret) < sizeof(struct tlv))
 			return 0;
-		ret += make_tlv(&buf[ret], buf_len, PP2_TYPE_NETNS, remote->proxy_netns->name_len, remote->proxy_netns->node.key);
+		ret += make_tlv(&buf[ret], (buf_len - ret), PP2_TYPE_NETNS, remote->proxy_netns->name_len, remote->proxy_netns->node.key);
 	}
 #endif