Avoid a crash in Skein_512::add_data if it is called with a zero-length

input vector.

1 files changed, 3 insertions, 0 deletions

diff --git a/src/hash/skein/skein_512.cpp b/src/hash/skein/skein_512.cpp
index eaef641ed..51eef262c 100644
--- a/src/hash/skein/skein_512.cpp
+++ b/src/hash/skein/skein_512.cpp
@@ -193,6 +193,9 @@ void Skein_512::clear() throw()
 
 void Skein_512::add_data(const byte input[], u32bit length)
    {
+   if(length == 0)
+      return;
+
    if(buf_pos)
       {
       buffer.copy(buf_pos, input, length);