From: Markus Koschany <apo@debian.org>
Date: Fri, 10 Feb 2017 03:01:38 +0100
Subject: BZ57544 infinite loop

Bug-Upstream: https://bz.apache.org/bugzilla/show_bug.cgi?id=60578
Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=854551
Origin: https://github.com/apache/tomcat80/commit/614e7f78aecc429d8740bb59900c2f9fbc86a788
---
 java/org/apache/coyote/http11/AbstractInputBuffer.java | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/java/org/apache/coyote/http11/AbstractInputBuffer.java b/java/org/apache/coyote/http11/AbstractInputBuffer.java
index eda3609..a1251d6 100644
--- a/java/org/apache/coyote/http11/AbstractInputBuffer.java
+++ b/java/org/apache/coyote/http11/AbstractInputBuffer.java
@@ -225,15 +225,10 @@ public abstract class AbstractInputBuffer<S> implements InputBuffer{
         request.recycle();
 
         // Copy leftover bytes to the beginning of the buffer
-        if (lastValid - pos > 0) {
-            int npos = 0;
-            int opos = pos;
-            while (lastValid - opos > opos - npos) {
-                System.arraycopy(buf, opos, buf, npos, opos - npos);
-                npos += pos;
-                opos += pos;
-            }
-            System.arraycopy(buf, opos, buf, npos, lastValid - opos);
+        if (lastValid - pos > 0 && pos > 0) {
+            System.arraycopy(buf, pos, buf, 0, lastValid - pos);
+            lastValid = lastValid - pos;
+            pos = 0;
         }
 
         // Recycle filters
@@ -242,12 +237,9 @@ public abstract class AbstractInputBuffer<S> implements InputBuffer{
         }
 
         // Reset pointers
-        lastValid = lastValid - pos;
-        pos = 0;
         lastActiveFilter = -1;
         parsingHeader = true;
         swallowInput = true;
-
     }