8259786: initialize last parameter of getpwuid_r

Reviewed-by: mdoerr, hseigel

Author: MBaesken

src/hotspot/os/posix/perfMemory_posix.cpp

@@ -461,7 +461,7 @@ static char* get_user_name(uid_t uid) {
 
   char* pwbuf = NEW_C_HEAP_ARRAY(char, bufsize, mtInternal);
 
-  struct passwd* p;
+  struct passwd* p = NULL;
   int result = getpwuid_r(uid, &pwent, pwbuf, (size_t)bufsize, &p);
 
   if (result != 0 || p == NULL || p->pw_name == NULL || *(p->pw_name) == '\0') {

src/jdk.security.auth/unix/native/libjaas/Unix.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -45,7 +45,7 @@ Java_com_sun_security_auth_module_UnixSystem_getUnixInfo
 
     int i;
     char pwd_buf[1024];
-    struct passwd *pwd;
+    struct passwd *pwd = NULL;
     struct passwd resbuf;
     jfieldID userNameID;
     jfieldID userID;