Refine port binding

src/local.c

@@ -156,13 +156,20 @@ create_and_bind(const char *addr, const char *port)
     memset(&hints, 0, sizeof(struct addrinfo));
     hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */
     hints.ai_socktype = SOCK_STREAM; /* We want a TCP socket */
+    result = NULL;
 
     s = getaddrinfo(addr, port, &hints, &result);
+
     if (s != 0) {
         LOGI("getaddrinfo: %s", gai_strerror(s));
         return -1;
     }
 
+    if (result == NULL) {
+        LOGE("Could not bind");
+        return -1;
+    }
+
     for (rp = result; rp != NULL; rp = rp->ai_next) {
         listen_sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
         if (listen_sock == -1) {
@@ -190,11 +197,7 @@ create_and_bind(const char *addr, const char *port)
         }
 
         close(listen_sock);
-    }
-
-    if (rp == NULL) {
-        LOGE("Could not bind");
-        return -1;
+        listen_sock = -1;
     }
 
     freeaddrinfo(result);

src/redir.c

@@ -140,12 +140,19 @@ create_and_bind(const char *addr, const char *port)
     hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */
     hints.ai_socktype = SOCK_STREAM; /* We want a TCP socket */
 
+    result = NULL;
+
     s = getaddrinfo(addr, port, &hints, &result);
     if (s != 0) {
         LOGI("getaddrinfo: %s", gai_strerror(s));
         return -1;
     }
 
+    if (result == NULL) {
+        LOGE("Could not bind");
+        return -1;
+    }
+
     for (rp = result; rp != NULL; rp = rp->ai_next) {
         listen_sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
         if (listen_sock == -1) {
@@ -173,11 +180,7 @@ create_and_bind(const char *addr, const char *port)
         }
 
         close(listen_sock);
-    }
-
-    if (rp == NULL) {
-        LOGE("Could not bind");
-        return -1;
+        listen_sock = -1;
     }
 
     freeaddrinfo(result);

src/server.c

@@ -328,6 +328,8 @@ create_and_bind(const char *host, const char *port, int mptcp)
     hints.ai_flags    = AI_PASSIVE | AI_ADDRCONFIG; /* For wildcard IP address */
     hints.ai_protocol = IPPROTO_TCP;
 
+    result = NULL;
+
     for (int i = 1; i < 8; i++) {
         s = getaddrinfo(host, port, &hints, &result);
         if (s == 0) {
@@ -343,6 +345,11 @@ create_and_bind(const char *host, const char *port, int mptcp)
         return -1;
     }
 
+    if (result == NULL) {
+        LOGE("Could not bind");
+        return -1;
+    }
+
     rp = result;
 
     /*
@@ -410,11 +417,7 @@ create_and_bind(const char *host, const char *port, int mptcp)
         }
 
         close(listen_sock);
-    }
-
-    if (rp == NULL) {
-        LOGE("Could not bind");
-        return -1;
+        listen_sock = -1;
     }
 
     freeaddrinfo(result);

src/tunnel.c

@@ -121,12 +121,19 @@ create_and_bind(const char *addr, const char *port)
     hints.ai_family   = AF_UNSPEC;   /* Return IPv4 and IPv6 choices */
     hints.ai_socktype = SOCK_STREAM; /* We want a TCP socket */
 
+    result = NULL;
+
     s = getaddrinfo(addr, port, &hints, &result);
     if (s != 0) {
         LOGI("getaddrinfo: %s", gai_strerror(s));
         return -1;
     }
 
+    if (result == NULL) {
+        LOGE("Could not bind");
+        return -1;
+    }
+
     for (rp = result; rp != NULL; rp = rp->ai_next) {
         listen_sock = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
         if (listen_sock == -1) {
@@ -154,11 +161,7 @@ create_and_bind(const char *addr, const char *port)
         }
 
         close(listen_sock);
-    }
-
-    if (rp == NULL) {
-        LOGE("Could not bind");
-        return -1;
+        listen_sock = -1;
     }
 
     freeaddrinfo(result);

src/udprelay.c

@@ -389,13 +389,13 @@ create_server_socket(const char *host, const char *port)
         return -1;
     }
 
-    rp = result;
-
-    if (rp == NULL) {
+    if (result == NULL) {
         LOGE("[udp] cannot bind");
         return -1;
     }
 
+    rp = result;
+
     /*
      * On Linux, with net.ipv6.bindv6only = 0 (the default), getaddrinfo(NULL) with
      * AI_PASSIVE returns 0.0.0.0 and :: (in this order). AI_PASSIVE was meant to
@@ -462,6 +462,7 @@ create_server_socket(const char *host, const char *port)
         }
 
         close(server_sock);
+        server_sock = -1;
     }
 
     freeaddrinfo(result);