From c0a2d2c6b14396a305eb1580c6e063f593df9ee8 Mon Sep 17 00:00:00 2001
From: HaseenaSainul <41037131+HaseenaSainul@users.noreply.github.com>
Date: Tue, 20 Aug 2024 18:41:16 +0530
Subject: [PATCH] JSON: add error logs for integer overflow case (#1713)

* JSON: add error logs for integer overflow case

* JSON: add logic to detect overflow using gcc __builtin_ overflow detection method

---------

Co-authored-by: Pierre Wielders <pierre@wielders.net>
Co-authored-by: Mateusz Daniluk <121170681+VeithMetro@users.noreply.github.com>
---
 Source/core/JSON.h | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/Source/core/JSON.h b/Source/core/JSON.h
index 10d7c5b15..c4ba49f78 100644
--- a/Source/core/JSON.h
+++ b/Source/core/JSON.h
@@ -744,13 +744,29 @@ namespace Core {
                 bool completed = ((_set & (ERROR|UNDEFINED)) != 0);
 
                 while ((loaded < maxLength) && (completed == false)) {
+#ifdef __WINDOWS__
+                    TYPE previous = _value;
+                    TYPE current = _value;
+#else
+                    bool overflow = false;
+#endif
                     if (isdigit(stream[loaded])) {
+#ifdef __WINDOWS__
                         _value *= (_set & 0x1F);
                         _value += (stream[loaded] - '0');
+                        current = _value / (_set & 0x1F);
+#else
+                        overflow = __builtin_mul_overflow(_value, (_set & 0x1F), &_value) || __builtin_add_overflow(stream[loaded] - '0', _value, &_value);
+#endif
                         loaded++;
                     } else if (isxdigit(stream[loaded])) {
+#ifdef __WINDOWS__
                         _value *= 16;
                         _value += (::toupper(stream[loaded]) - 'A') + 10;
+                        current = _value / 16;
+#else
+                        overflow = __builtin_mul_overflow(_value, 16, &_value) || __builtin_add_overflow((::toupper(stream[loaded]) - 'A') + 10, _value, &_value);
+#endif
                         loaded++;
                     } else if (((_set & QUOTED) != 0) && (stream[loaded] == '\"')) {
                         completed = true;
@@ -764,6 +780,16 @@ namespace Core {
                         _set |= ERROR;
                         completed = true;
                     }
+
+#ifdef __WINDOWS__
+                    if (previous != current) {
+#else
+                    if (overflow == true) {
+#endif
+                        error = Error{ "Integer overflow, it should be in the integer type range" };
+                        _set |= ERROR;
+                        completed = true;
+                    }
                 }
 
                 if ((_set & (ERROR | QUOTED)) == (ERROR | QUOTED)) {