diff --git a/tools/source/stream/stream.cxx b/tools/source/stream/stream.cxx
index 77d06abfe0fd..01c33a3ab534 100644
--- a/tools/source/stream/stream.cxx
+++ b/tools/source/stream/stream.cxx
@@ -1646,7 +1646,7 @@ std::size_t SvMemoryStream::PutData( const void* pData, std::size_t nCount )
         }
         else
         {
-            const bool bSourceDataIsInsideBuffer = pData >= pBuf && pData <= (pBuf + nSize);
+            const bool bSourceDataIsInsideBuffer = pData >= pBuf && pData < (pBuf + nSize);
             std::ptrdiff_t const offset = bSourceDataIsInsideBuffer ? static_cast<const char*>(pData) - reinterpret_cast<const char*>(pBuf) : 0;
             tools::Long nNewResize;
             if( nSize && nSize > nResize )