xdp-tcp: bugfix: check presence in syn_table before adding

diff --git a/src/libknot/xdp/tcp.c b/src/libknot/xdp/tcp.c
index c6c10ec3c6b1b290f0a4bb375062a4d504702e41..b99ba77a522e63146fad93d669676fe41556da34 100644 (file)
--- a/src/libknot/xdp/tcp.c
+++ b/src/libknot/xdp/tcp.c
@@ -134,7 +134,9 @@ static knot_tcp_conn_t **tcp_table_lookup(const struct sockaddr_in6 *rem,
                                           const struct sockaddr_in6 *loc,
                                           uint64_t *hash, knot_tcp_table_t *table)
 {
-       *hash = hash_four_tuple(rem, loc, table);
+       if (*hash == 0) {
+               *hash = hash_four_tuple(rem, loc, table);
+       }
        size_t sdl = sockaddr_data_len(rem, loc);
        knot_tcp_conn_t **res = table->conns + (*hash % table->size);
        while (*res != NULL) {
@@ -150,7 +152,7 @@ static knot_tcp_conn_t **tcp_table_lookup(const struct sockaddr_in6 *rem,
 static knot_tcp_conn_t **tcp_table_re_lookup(knot_tcp_conn_t *conn,
                                              knot_tcp_table_t *table)
 {
-       uint64_t unused_hash;
+       uint64_t unused_hash = 0;
        knot_tcp_conn_t **res = tcp_table_lookup(&conn->ip_rem, &conn->ip_loc,
                                                 &unused_hash, table);
        assert(*res == conn);
@@ -288,7 +290,7 @@ int knot_tcp_recv(knot_tcp_relay_t *relays, knot_xdp_msg_t *msgs, uint32_t count
                        continue;
                }
 
-               uint64_t conn_hash;
+               uint64_t conn_hash = 0;
                knot_tcp_conn_t **pconn = tcp_table_lookup(&msg->ip_from, &msg->ip_to,
                                                           &conn_hash, tcp_table);
                knot_tcp_conn_t *conn = *pconn;
@@ -332,9 +334,15 @@ int knot_tcp_recv(knot_tcp_relay_t *relays, knot_xdp_msg_t *msgs, uint32_t count
                        if (conn == NULL) {
                                bool synack = (msg->flags & KNOT_XDP_MSG_ACK);
 
-                               ret = tcp_table_add(msg, conn_hash,
-                                                   (syn_table == NULL || synack) ? tcp_table : syn_table,
-                                                   &relay->conn);
+                               knot_tcp_table_t *add_table = tcp_table;
+                               if (syn_table != NULL && !synack) {
+                                       add_table = syn_table;
+                                       if (*tcp_table_lookup(&msg->ip_from, &msg->ip_to, &conn_hash, syn_table) != NULL) {
+                                               break;
+                                       }
+                               }
+
+                               ret = tcp_table_add(msg, conn_hash, add_table, &relay->conn);
                                if (ret == KNOT_EOK) {
                                        relay->action = synack ? XDP_TCP_ESTABLISH : XDP_TCP_SYN;
                                        if (!(ignore & XDP_TCP_IGNORE_ESTABLISH)) {
@@ -357,9 +365,8 @@ int knot_tcp_recv(knot_tcp_relay_t *relays, knot_xdp_msg_t *msgs, uint32_t count
                        break;
                case KNOT_XDP_MSG_ACK:
                        if (!seq_ack_match) {
-                               uint64_t syn_hash;
                                if (syn_table != NULL && msg->payload.iov_len == 0 &&
-                                   (pconn = tcp_table_lookup(&msg->ip_from, &msg->ip_to, &syn_hash, syn_table)) != NULL &&
+                                   (pconn = tcp_table_lookup(&msg->ip_from, &msg->ip_to, &conn_hash, syn_table)) != NULL &&
                                    (conn = *pconn) != NULL && check_seq_ack(msg, conn)) {
                                        // move conn from syn_table to tcp_table
                                        tcp_table_remove(pconn, syn_table);

diff --git a/tests/libknot/test_xdp_tcp.c b/tests/libknot/test_xdp_tcp.c
index b88bee7785eac062be0b0d7a7723707396054d86..edd91c1421aa9a12032a2b983186268245591b60 100644 (file)
--- a/tests/libknot/test_xdp_tcp.c
+++ b/tests/libknot/test_xdp_tcp.c
@@ -75,7 +75,7 @@ static void tcp_cleanup(knot_tcp_table_t *tcp_table, uint32_t timeout,
  */
 static knot_tcp_conn_t *tcp_table_find(knot_tcp_table_t *table, knot_xdp_msg_t *msg_recv)
 {
-       uint64_t unused;
+       uint64_t unused = 0;
        return *tcp_table_lookup(&msg_recv->ip_from, &msg_recv->ip_to, &unused, table);
 }