etcp: защита от UAF в start_keepalive_timer/enter_ready_tcp + диагностика указателей

- start_keepalive_timer: guard !link->etcp->instance->ua (SIGSEGV на 80 строке)
- etcp_link_enter_ready_tcp: return при etcp->state==2 после reinit/apply_reset/conn_ready
- tcp_server_on_link/enter_ready_tcp: DEBUG_CATEGORY_DEBUG с адресами link/etcp/inst/ua
- topo_node: убрать лишние DEBUG_CATEGORY_DEBUG (chain_rtt)

src/routing_layer/topo_node.c

@@ -564,24 +564,17 @@ void topo_node_ping_update_rtt(struct TOPO_GROUPS* groups, uint64_t node_id, uin
 
 uint16_t topo_get_chain_rtt(struct TOPO_GROUP_NODE* nq) {
     if (!nq || !nq->paths || !nq->paths->head) {
-        DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "chain_rtt: nid=%016llx NO PATHS", (unsigned long long)(nq ? nq->node_id : 0));
         return 0xFFFF;
     }
     uint16_t best = 0xFFFF;
     for (struct ll_entry* e = nq->paths->head; e; e = e->next) {
         struct TOPO_NODEPATH* p = (struct TOPO_NODEPATH*)e;
         if (!p->conn || !p->conn->links_up || !p->conn->rtt_last) {
-            DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "chain_rtt: nid=%016llx SKIP conn=%s up=%d rtt=%u cum=%u",
-                       (unsigned long long)nq->node_id, p->conn ? p->conn->log_name : "NULL",
-                       p->conn ? p->conn->links_up : 0, p->conn ? p->conn->rtt_last : 0, p->cumulative_rtt);
             continue;
         }
         uint16_t total = (uint16_t)((uint32_t)p->conn->rtt_last + p->cumulative_rtt);
-        DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "chain_rtt: nid=%016llx PATH %s rtt=%u+cum=%u=%u best=%u",
-                   (unsigned long long)nq->node_id, p->conn->log_name, p->conn->rtt_last, p->cumulative_rtt, total, best);
         if (total < best) best = total;
     }
-    DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "chain_rtt: nid=%016llx RESULT=%u(0x%04X)", (unsigned long long)nq->node_id, best, best);
     return best;
 }
 

src/transport_layer/etcp_connections.c

@@ -48,6 +48,8 @@ void etcp_link_enter_ready_tcp(struct ETCP_LINK *link);
 // TCP server: on new incoming connection → create ETCP_LINK + enter ready
 void tcp_server_on_link(struct stcp_link *link, struct ETCP_SOCKET *tcp_sock) {
     struct UTUN_INSTANCE *inst = tcp_sock->instance;
+    DEBUG_DEBUG(DEBUG_CATEGORY_DEBUG, "tcp_server_on_link: link=%p tcp_sock=%p inst=%p inst->ua=%p",
+                (void*)link, (void*)tcp_sock, (void*)inst, (void*)(inst ? inst->ua : NULL));
     const uint8_t *pubkey = stcp_link_get_peer_pubkey(link);
     if (!pubkey) { DEBUG_ERROR(DEBUG_CATEGORY_ETCP, "tcp_server_on_link: no peer pubkey"); return; }
     uint64_t node_id = sc_derive_node_id_from_pubkey(pubkey);
@@ -1066,6 +1068,9 @@ void etcp_link_close(struct ETCP_LINK* link) {
 void etcp_link_enter_ready_tcp(struct ETCP_LINK *link) {
     if (!link || !link->etcp) return;
     struct ETCP_CONN *etcp = link->etcp;
+    DEBUG_DEBUG(DEBUG_CATEGORY_DEBUG, "enter_ready_tcp: link=%p etcp=%p inst=%p ua=%p conn_state=%d tcp_link=%p",
+                (void*)link, (void*)etcp, (void*)etcp->instance, (void*)(etcp->instance ? etcp->instance->ua : NULL),
+                etcp->state, (void*)link->tcp_link);
 
     /* Синхронизация got_initial_pkt: если я грязный (1) а пир чистый (0) → сбросить */
     if (link->tcp_link) {
@@ -1077,6 +1082,7 @@ void etcp_link_enter_ready_tcp(struct ETCP_LINK *link) {
             etcp_conn_reinit(etcp, "tcp peer clean");
         }
         etcp_conn_apply_peer_reset_id(etcp, peer_rid);
+        if (etcp->state == 2) { DEBUG_ERROR(DEBUG_CATEGORY_DEBUG, "enter_ready_tcp: conn DELETED after reinit/apply_reset, link=%p", (void*)link); return; }
 
         link->peer_device_type = stcp_link_get_peer_device_type(link->tcp_link);
         {   uint16_t peer_ka = stcp_link_get_peer_keepalive_interval(link->tcp_link);
@@ -1092,6 +1098,7 @@ void etcp_link_enter_ready_tcp(struct ETCP_LINK *link) {
     etcp->tcp_link_count++;
     if (link->tcp_link) { const uint8_t* ed = stcp_link_get_peer_ed25519_pubkey(link->tcp_link); if (ed) memcpy(etcp->peer_ed25519_pubkey, ed, SC_PUBKEY_SIZE); }
     if (etcp->initialized == 0) etcp_conn_ready(etcp);
+    if (etcp->state == 2) { DEBUG_ERROR(DEBUG_CATEGORY_DEBUG, "enter_ready_tcp: conn DELETED after conn_ready, link=%p", (void*)link); return; }
     etcp_link_send_keepalive(link);
     start_keepalive_timer(link);
     loadbalancer_link_ready(link);

src/transport_layer/etcp_keepalive.c

@@ -69,6 +69,13 @@ static int etcp_all_links_down(struct ETCP_CONN* etcp) {
 }
 
 void start_keepalive_timer(struct ETCP_LINK* link) {
+    if (!link || !link->etcp || !link->etcp->instance || !link->etcp->instance->ua) {
+        DEBUG_ERROR(DEBUG_CATEGORY_DEBUG, "start_keepalive_timer: BAD link=%p etcp=%p inst=%p ua=%p",
+                    (void*)link, (void*)(link ? link->etcp : NULL),
+                    (void*)(link && link->etcp ? link->etcp->instance : NULL),
+                    (void*)(link && link->etcp && link->etcp->instance ? link->etcp->instance->ua : NULL));
+        return;
+    }
     // Start keepalive timer
     if (link->init_timer) {// cancel init timer
         uasync_cancel_timeout(link->etcp->instance->ua, link->init_timer);