dns: fix crash on setServers with port 0

Signed-off-by: Lazizbek Ergashev <lazerg2@gmail.com>
PR-URL: #65009
Fixes: #65006
Reviewed-By: René <contact.9a5d6388@renegade334.me.uk>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Tim Perry <pimterry@gmail.com>

Author: lazerg

src/cares_wrap.cc

@@ -2275,13 +2275,13 @@ void SetServers(const FunctionCallbackInfo<Value>& args) {
     if (!elm->Get(env->context(), 1).ToLocal(&ipValue)) return;
     if (!elm->Get(env->context(), 2).ToLocal(&portValue)) return;
 
-    CHECK(familyValue->Int32Value(env->context()).FromJust());
+    CHECK(familyValue->IsInt32());
     CHECK(ipValue->IsString());
-    CHECK(portValue->Int32Value(env->context()).FromJust());
+    CHECK(portValue->IsInt32());
 
-    int fam = familyValue->Int32Value(env->context()).FromJust();
+    int32_t fam = familyValue.As<Int32>()->Value();
     node::Utf8Value ip(env->isolate(), ipValue);
-    int port = portValue->Int32Value(env->context()).FromJust();
+    int32_t port = portValue.As<Int32>()->Value();
 
     if (!csv.empty()) csv += ',';
 

test/parallel/test-dns.js

@@ -134,6 +134,10 @@ const portsExpected = [
 dns.setServers(ports);
 assert.deepStrictEqual(dns.getServers(), portsExpected);
 
+// Port 0 means "use the default port" for c-ares.
+dns.setServers(['4.4.4.4:0', '[2001:4860:4860::8888]:0']);
+assert.deepStrictEqual(dns.getServers(), ['4.4.4.4', '2001:4860:4860::8888']);
+
 // Link-local IPv6 addresses require a zone index (scope id) to be usable;
 // c-ares drops link-local servers configured without one.
 dns.setServers(['[fe80::483a:5aff:fee6:1f04]%eth0']);