check size of buffer in yy_scan_buffer

1 files changed, 2 insertions, 1 deletions

diff --git a/flex.skl b/flex.skl
index a974fb0..7cf432a 100644
--- a/flex.skl
+++ b/flex.skl
@@ -1162,7 +1162,8 @@ yy_size_t size;
 	{
 	YY_BUFFER_STATE b;
 
-	if ( base[size-2] != YY_END_OF_BUFFER_CHAR ||
+	if ( size < 2 ||
+	     base[size-2] != YY_END_OF_BUFFER_CHAR ||
 	     base[size-1] != YY_END_OF_BUFFER_CHAR )
 		/* They forgot to leave room for the EOB's. */
 		return 0;