From ec554c067caf3b2a7757ec290ea68524a897273e Mon Sep 17 00:00:00 2001
From: kpayson64 <kpayson@google.com>
Date: Mon, 23 Jan 2017 13:05:08 -0800
Subject: [PATCH] Fix buffer underflow bug (#58)

In the event the engine returns BUFFER_UNDERFLOW, and was not able to produce any bytes as a result, the read() returns 0 instead of continuing to read from the socket.
---
 common/src/main/java/org/conscrypt/OpenSSLEngineSocketImpl.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/common/src/main/java/org/conscrypt/OpenSSLEngineSocketImpl.java b/common/src/main/java/org/conscrypt/OpenSSLEngineSocketImpl.java
index a8bfc60dd..5fd011fcc 100644
--- a/common/src/main/java/org/conscrypt/OpenSSLEngineSocketImpl.java
+++ b/common/src/main/java/org/conscrypt/OpenSSLEngineSocketImpl.java
@@ -522,7 +522,7 @@ public int read(byte[] b, int off, int len) throws IOException {
                             if (engineResult.getHandshakeStatus() == HandshakeStatus.FINISHED) {
                                 completeHandshake();
                             }
-                            if (engineResult.bytesProduced() == 0) {
+                            if (!needMoreData && engineResult.bytesProduced() == 0) {
                                 // Read successfully, but produced no data. Possibly part of a
                                 // handshake.
                                 return 0;