os: fix memory leak in userInfo()

This previously leaked memory in the ‘success’ case.

PR-URL: #23893
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: addaleax

Diff for: src/node_os.cc

@@ -368,6 +368,8 @@ static void GetUserInfo(const FunctionCallbackInfo<Value>& args) {
     return args.GetReturnValue().SetUndefined();
   }
 
+  OnScopeLeave free_passwd([&]() { uv_os_free_passwd(&pwd); });
+
   Local<Value> error;
 
   Local<Value> uid = Number::New(env->isolate(), pwd.uid);
@@ -389,7 +391,6 @@ static void GetUserInfo(const FunctionCallbackInfo<Value>& args) {
 
   if (username.IsEmpty() || homedir.IsEmpty() || shell.IsEmpty()) {
     CHECK(!error.IsEmpty());
-    uv_os_free_passwd(&pwd);
     env->isolate()->ThrowException(error);
     return;
   }