From 5319dedb1a6480c2e9b7f6bcdb32549ab723493b Mon Sep 17 00:00:00 2001
From: Vladimir Glavnyy <31897320+vglavnyy@users.noreply.github.com>
Date: Tue, 2 Mar 2021 04:40:58 +0700
Subject: [PATCH] [idl_parser, JSON] Disable parsing of JSON for incomplete
 schemes (#6493)

This commit disable JSON parsing for an incomplete scheme if JSON object is embedded into one file with the scheme.
This should improve the quality of OSS-Fuzz inputs for the parser_fuzzer target.
---
 src/idl_parser.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/idl_parser.cpp b/src/idl_parser.cpp
index 8cfd04b..87b999d 100644
--- a/src/idl_parser.cpp
+++ b/src/idl_parser.cpp
@@ -3189,6 +3189,9 @@ CheckedError Parser::ParseRoot(const char *source, const char **include_paths,
       }
     }
   }
+  // Parse JSON object only if the scheme has been parsed.
+  if (token_ == '{') { ECHECK(DoParseJson()); }
+  EXPECT(kTokenEof);
   return NoError();
 }
 
@@ -3308,7 +3311,7 @@ CheckedError Parser::DoParse(const char *source, const char **include_paths,
     } else if (IsIdent("namespace")) {
       ECHECK(ParseNamespace());
     } else if (token_ == '{') {
-      ECHECK(DoParseJson());
+      return NoError();
     } else if (IsIdent("enum")) {
       ECHECK(ParseEnum(false, nullptr));
     } else if (IsIdent("union")) {
-- 
2.7.4