From e4154bcb0b91acfe5cf041208fc255aff16143be Mon Sep 17 00:00:00 2001
From: Norman Maurer <norman_maurer@apple.com>
Date: Fri, 19 Aug 2016 14:15:19 +0200
Subject: [PATCH] [#5720] Static initializers can cause deadlock

Motivation:

SystemPropertyUtil requires InternalLoggerFactory requires ThreadLocalRandom requires SystemPropertyUtil. This can lead to a dead-lock.

Modifications:

Ensure ThreadLocalRandom does not require SystemPropertyUtil during initialization.

Result:

No more deadlock possible.
---
 .../io/netty/util/internal/ThreadLocalRandom.java    | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/common/src/main/java/io/netty/util/internal/ThreadLocalRandom.java b/common/src/main/java/io/netty/util/internal/ThreadLocalRandom.java
index fb1594bcae..f8c6a539d4 100644
--- a/common/src/main/java/io/netty/util/internal/ThreadLocalRandom.java
+++ b/common/src/main/java/io/netty/util/internal/ThreadLocalRandom.java
@@ -66,8 +66,7 @@ public final class ThreadLocalRandom extends Random {
 
     private static final AtomicLong seedUniquifier = new AtomicLong();
 
-    private static volatile long initialSeedUniquifier =
-            SystemPropertyUtil.getLong("io.netty.initialSeedUniquifier", 0);
+    private static volatile long initialSeedUniquifier;
 
     private static final Thread seedGeneratorThread;
     private static final BlockingQueue<Long> seedQueue;
@@ -75,11 +74,18 @@ public final class ThreadLocalRandom extends Random {
     private static volatile long seedGeneratorEndTime;
 
     static {
+        initialSeedUniquifier = AccessController.doPrivileged(new PrivilegedAction<Long>() {
+            @Override
+            public Long run() {
+                return Long.getLong("io.netty.initialSeedUniquifier", 0);
+            }
+        });
+
         if (initialSeedUniquifier == 0) {
             boolean secureRandom = AccessController.doPrivileged(new PrivilegedAction<Boolean>() {
                 @Override
                 public Boolean run() {
-                    return SystemPropertyUtil.getBoolean("java.util.secureRandomSeed", false);
+                    return Boolean.getBoolean("java.util.secureRandomSeed");
                 }
             });