Merge pull request #154 from webmaster128/bounds-fixes

Remainings fixes before Botan runs fine in debug mode

1 files changed, 5 insertions, 1 deletions

diff --git a/src/lib/math/bigint/bigint.h b/src/lib/math/bigint/bigint.h
index 3f329c451..fed986882 100644
--- a/src/lib/math/bigint/bigint.h
+++ b/src/lib/math/bigint/bigint.h
@@ -278,7 +278,11 @@ class BOTAN_DLL BigInt
 
         if(top_word < size())
            {
-           clear_mem(&m_reg[top_word+1], size() - (top_word + 1));
+           const auto len = size() - (top_word + 1);
+           if (len > 0)
+              {
+              clear_mem(&m_reg[top_word+1], len);
+              }
            m_reg[top_word] &= mask;
            }
         }