From feb11e4a39c7ac3b4989ae2b7e5c8ad17cc1e60e Mon Sep 17 00:00:00 2001
From: mattijs <mattijs>
Date: Wed, 20 Dec 2017 15:28:20 +0000
Subject: [PATCH] BUG: UIPstream: sending zero sized string accesses beyond
 buffer. Fixes #676

---
 src/OpenFOAM/db/IOstreams/Pstreams/UIPstream.C | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/OpenFOAM/db/IOstreams/Pstreams/UIPstream.C b/src/OpenFOAM/db/IOstreams/Pstreams/UIPstream.C
index 76f9706093..ddee4450a4 100644
--- a/src/OpenFOAM/db/IOstreams/Pstreams/UIPstream.C
+++ b/src/OpenFOAM/db/IOstreams/Pstreams/UIPstream.C
@@ -106,7 +106,14 @@ inline Foam::Istream& Foam::UIPstream::readStringFromBuffer(std::string& str)
     size_t len;
     readFromBuffer(len);
 
-    str.assign(&externalBuf_[externalBufPosition_], len);
+    if (len == 0)
+    {
+        str.clear();
+    }
+    else
+    {
+        str.assign(&externalBuf_[externalBufPosition_], len);
+    }
 
     externalBufPosition_ += len;
     checkEof();