Make sure that [::1] is recognized as a private address

Fixes bug 8377; bugfix on 0.2.1.3-alpha.

changes/bug8377

@@ -0,0 +1,3 @@
+  o Minor bugfixes:
+    - Correctly recognize that [::1] is a loopback address. Fixes bug #8377;
+      bugfix on 0.2.1.3-alpha.

src/common/address.c

@@ -779,7 +779,8 @@ tor_addr_is_loopback(const tor_addr_t *addr)
     case AF_INET6: {
       /* ::1 */
       uint32_t *a32 = tor_addr_to_in6_addr32(addr);
-      return (a32[0] == 0) && (a32[1] == 0) && (a32[2] == 0) && (a32[3] == 1);
+      return (a32[0] == 0) && (a32[1] == 0) && (a32[2] == 0) &&
+        (ntohl(a32[3]) == 1);
     }
     case AF_INET:
       /* 127.0.0.1 */