commit 6aba23f4a8628d599a9ef7fa4811c4ff6e4070e2
author kabeer27 <32016558+kabeer27@users.noreply.github.com> Fri May 29 13:50:26 2020
committer GitHub <noreply@github.com> Fri May 29 13:50:26 2020
tree f8d7ad1720d718e779ca9fd1f6f8adbe30430abd
parent c161f4ac69633deb2ed43bc8569cb9b183f63c32

Fixes Oss-Fuzz issue: 21916 (#1180)

* Fix heap-buffer-overflow in json_reader

src/lib_json/json_reader.cpp

diff --git a/src/lib_json/json_reader.cpp b/src/lib_json/json_reader.cpp
index 2dca4ca..23cbe60 100644
--- a/src/lib_json/json_reader.cpp
+++ b/src/lib_json/json_reader.cpp
@@ -1270,7 +1270,7 @@
 void OurReader::skipBom(bool skipBom) {
   // The default behavior is to skip BOM.
   if (skipBom) {
-    if (strncmp(begin_, "\xEF\xBB\xBF", 3) == 0) {
+    if ((end_ - begin_) >= 3 && strncmp(begin_, "\xEF\xBB\xBF", 3) == 0) {
       begin_ += 3;
       current_ = begin_;
     }