fix remote_proxy: cleanup socket on EOF/error/connect-fail to prevent infinite callback loop

src/remote_proxy.c

@@ -30,6 +30,7 @@ static struct remote_proxy_ctx* g_rp_ctx = NULL;
 static void rp_sock_read_cb (socket_t sock, void* arg);
 static void rp_sock_write_cb(socket_t sock, void* arg);
 static void rp_sock_error_cb(socket_t sock, void* arg);
+static void rp_conn_free(struct remote_proxy_conn* rc);
 
 static int rp_send_msg(struct UTUN_INSTANCE* inst, uint64_t dst, uint8_t subcmd,
                         uint64_t sid, const uint8_t* data, size_t len) {
@@ -62,13 +63,13 @@ static void rp_sock_read_cb(socket_t sock, void* arg) {
     if (n > 0) {
         struct UTUN_INSTANCE* inst = rc->ctx ? rc->ctx->inst : NULL;
         if (inst) rp_send_msg(inst, rc->peer_node_id, TCP_PROXY_SUBCMD_DATA, rc->stream_id, buf, (size_t)n);
-    } else if (n == 0) {
-        DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "remote_proxy: EOF stream=%016llx", (unsigned long long)rc->stream_id);
+    } else {
+        if (n == 0) DEBUG_INFO(DEBUG_CATEGORY_SOCKET, "remote_proxy: EOF stream=%016llx", (unsigned long long)rc->stream_id);
+        else DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "remote_proxy: recv error %s", strerror(errno));
         struct UTUN_INSTANCE* inst = rc->ctx ? rc->ctx->inst : NULL;
         if (inst) rp_send_msg(inst, rc->peer_node_id, TCP_PROXY_SUBCMD_CLOSE, rc->stream_id, NULL, 0);
         rc->connected = -1;
-    } else if (errno != EAGAIN && errno != EWOULDBLOCK && errno != EINTR) {
-        DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "remote_proxy: recv error %s", strerror(errno));
+        rp_conn_free(rc);
     }
 }
 
@@ -93,21 +94,30 @@ static void rp_sock_write_cb(socket_t sock, void* arg) {
             struct UTUN_INSTANCE* inst = rc->ctx ? rc->ctx->inst : NULL;
             if (inst) rp_send_connected(inst, rc->peer_node_id, rc->stream_id, 0, TCP_PROXY_CONNECTED_REFUSED);
             rc->connected = -1;
+            rp_conn_free(rc);
         }
     }
 }
 
 static void rp_sock_error_cb(socket_t sock, void* arg) {
     (void)sock; struct remote_proxy_conn* rc = (struct remote_proxy_conn*)arg;
-    DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "remote_proxy: socket error stream=%016llx", (unsigned long long)rc->stream_id);
-    if (rc) rc->connected = -1;
+    if (!rc || rc->sock == SOCKET_INVALID) return;
+    DEBUG_ERROR(DEBUG_CATEGORY_SOCKET, "remote_proxy: socket error stream=%016llx", (unsigned long long)(rc ? rc->stream_id : 0));
+    rc->connected = -1;
+    struct UTUN_INSTANCE* inst = rc->ctx ? rc->ctx->inst : NULL;
+    if (inst) rp_send_msg(inst, rc->peer_node_id, TCP_PROXY_SUBCMD_CLOSE, rc->stream_id, NULL, 0);
+    rp_conn_free(rc);
 }
 
 static void rp_conn_free(struct remote_proxy_conn* rc) {
     if (!rc) return;
+    if (rc->ctx) {
+        struct remote_proxy_conn** prev = &rc->ctx->conns;
+        while (*prev) { if (*prev == rc) { *prev = rc->next; break; } prev = &(*prev)->next; }
+    }
     if (rc->sock != SOCKET_INVALID) {
         if (rc->read_id) { uasync_remove_socket_t(rc->ua, rc->sock); rc->read_id = NULL; }
-        socket_close_wrapper(rc->sock);
+        socket_close_wrapper(rc->sock); rc->sock = SOCKET_INVALID;
     }
     u_free(rc);
 }