From 06436efaa1b118eac3526d8f77d9e159d0292959 Mon Sep 17 00:00:00 2001
From: Norman Maurer <norman_maurer@apple.com>
Date: Tue, 3 May 2016 10:32:25 +0200
Subject: [PATCH] [#5190] Ensure memory is not leaked when readEndOfLine(...)
 throws an exception.

Motivation:

We need to ensure we not retain the buffer until readEndOfLine(...) completes as otherwise we may leak memory in the case of an exception.

Modifications:

Only call retain after readEndOfLine(...) returns.

Result:

No more leak in case of exception while decoding redis messages.
---
 .../main/java/io/netty/handler/codec/redis/RedisDecoder.java | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/codec-redis/src/main/java/io/netty/handler/codec/redis/RedisDecoder.java b/codec-redis/src/main/java/io/netty/handler/codec/redis/RedisDecoder.java
index 54891a11c4..0fe9f6e509 100644
--- a/codec-redis/src/main/java/io/netty/handler/codec/redis/RedisDecoder.java
+++ b/codec-redis/src/main/java/io/netty/handler/codec/redis/RedisDecoder.java
@@ -205,9 +205,10 @@ public final class RedisDecoder extends ByteToMessageDecoder {
 
         // if this is last frame.
         if (readableBytes >= remainingBulkLength + RedisConstants.EOL_LENGTH) {
-            ByteBuf content = in.readSlice(remainingBulkLength).retain();
+            ByteBuf content = in.readSlice(remainingBulkLength);
             readEndOfLine(in);
-            out.add(new DefaultLastBulkStringRedisContent(content));
+            // Only call retain after readEndOfLine(...) as the method may throw an exception.
+            out.add(new DefaultLastBulkStringRedisContent(content.retain()));
             resetDecoder();
             return true;
         }