From f01a590154f05247ce39bc218880bf0510c6508f Mon Sep 17 00:00:00 2001
From: Norman Maurer <norman_maurer@apple.com>
Date: Wed, 9 May 2018 08:57:20 +0200
Subject: [PATCH] Enfore upper limit for minTtl when using DefaultCacheEntry.
 (#7920)

Motivation:

a598c3b69b55f930b91a8265f42d1a3cceb75ddd added a upper limit for ttl but missed to also do the same for minTtl.

Modifications:

- Add upper limit for minTtl
- Add testcase.

Result:

No more IllegalArgumentException possible.
---
 .../java/io/netty/resolver/dns/DefaultDnsCache.java |  4 ++--
 .../io/netty/resolver/dns/DefaultDnsCacheTest.java  | 13 +++++++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/resolver-dns/src/main/java/io/netty/resolver/dns/DefaultDnsCache.java b/resolver-dns/src/main/java/io/netty/resolver/dns/DefaultDnsCache.java
index 3cbb1a367d..d5431362fe 100644
--- a/resolver-dns/src/main/java/io/netty/resolver/dns/DefaultDnsCache.java
+++ b/resolver-dns/src/main/java/io/netty/resolver/dns/DefaultDnsCache.java
@@ -65,8 +65,8 @@ public class DefaultDnsCache implements DnsCache {
      * @param negativeTtl the TTL for failed queries
      */
     public DefaultDnsCache(int minTtl, int maxTtl, int negativeTtl) {
-        this.minTtl = checkPositiveOrZero(minTtl, "minTtl");
-        this.maxTtl = checkPositiveOrZero(maxTtl, "maxTtl");
+        this.minTtl = Math.min(MAX_SUPPORTED_TTL_SECS, checkPositiveOrZero(minTtl, "minTtl"));
+        this.maxTtl = Math.min(MAX_SUPPORTED_TTL_SECS, checkPositiveOrZero(maxTtl, "maxTtl"));
         if (minTtl > maxTtl) {
             throw new IllegalArgumentException(
                     "minTtl: " + minTtl + ", maxTtl: " + maxTtl + " (expected: 0 <= minTtl <= maxTtl)");
diff --git a/resolver-dns/src/test/java/io/netty/resolver/dns/DefaultDnsCacheTest.java b/resolver-dns/src/test/java/io/netty/resolver/dns/DefaultDnsCacheTest.java
index 806f8f9e90..17aba98e3c 100644
--- a/resolver-dns/src/test/java/io/netty/resolver/dns/DefaultDnsCacheTest.java
+++ b/resolver-dns/src/test/java/io/netty/resolver/dns/DefaultDnsCacheTest.java
@@ -86,6 +86,19 @@ public class DefaultDnsCacheTest {
         }
     }
 
+    @Test
+    public void testExpireWithToBigMinTTL() {
+        EventLoopGroup group = new NioEventLoopGroup(1);
+
+        try {
+            EventLoop loop = group.next();
+            final DefaultDnsCache cache = new DefaultDnsCache(Integer.MAX_VALUE, Integer.MAX_VALUE, Integer.MAX_VALUE);
+            assertNotNull(cache.cache("netty.io", null, NetUtil.LOCALHOST, 100, loop));
+        } finally {
+            group.shutdownGracefully();
+        }
+    }
+
     @Test
     public void testAddMultipleAddressesForSameHostname() throws Exception {
         InetAddress addr1 = InetAddress.getByAddress(new byte[] { 10, 0, 0, 1 });