fix: Prevent stack overflow in variant conversion

CHANGELOG.md

@@ -11,6 +11,7 @@
 - Prevent feedback loops in SentryLogger ([#275](https://github.com/getsentry/sentry-godot/pull/275))
 - Fix `release` option not honored if set to a custom value in the project settings, and fix parsing of `app_name`/`app_version` replacement tokens if set via a configuration script. ([#276](https://github.com/getsentry/sentry-godot/pull/276))
 - Remove `libatomic.so.1` dependency on Linux ([#278](https://github.com/getsentry/sentry-godot/pull/278))
+- Prevent stack overflow in variant conversion ([#284](https://github.com/getsentry/sentry-godot/pull/284))
 
 ## 1.0.0-alpha.2
 

project/test/suites/test_sdk.gd

@@ -46,3 +46,11 @@ func test_remove_tag() -> void:
 	await assert_signal(monitor).is_emitted("callback_processed")
 
 	SentrySDK._unset_before_send()
+
+
+## SentrySDK Variant conversion should not cause stack overflow.
+func test_variant_conversion_against_stack_overflow() -> void:
+	var dict: Dictionary = { "some_key": "some_value"}
+	var arr: Array = [dict, "another_value"]
+	dict["array"] = arr
+	SentrySDK.set_context("broken_context", dict)

src/sentry/common_defs.h

@@ -4,4 +4,10 @@
 #define SENTRY_SCREENSHOT_FN "screenshot.jpg"
 #define SENTRY_VIEW_HIERARCHY_FN "view-hierarchy.json"
 
+namespace sentry {
+
+constexpr int VARIANT_CONVERSION_MAX_DEPTH = 32;
+
+};
+
 #endif // SENTRY_COMMON_DEFS_H

src/sentry/native/native_util.cpp

@@ -1,8 +1,10 @@
 #include "native_util.h"
 
+#include "sentry/common_defs.h"
+
 namespace sentry::native {
 
-sentry_value_t variant_to_sentry_value(const Variant &p_variant) {
+sentry_value_t variant_to_sentry_value(const Variant &p_variant, int p_depth) {
 	switch (p_variant.get_type()) {
 		case Variant::Type::NIL: {
 			return sentry_value_new_null();
@@ -20,12 +22,17 @@ sentry_value_t variant_to_sentry_value(const Variant &p_variant) {
 			return sentry_value_new_string(((String)p_variant).utf8());
 		} break;
 		case Variant::Type::DICTIONARY: {
+			if (p_depth > VARIANT_CONVERSION_MAX_DEPTH) {
+				ERR_PRINT_ONCE("Sentry: Maximum Variant conversion depth reached!");
+				return sentry_value_new_string("{...}");
+			}
+
 			Dictionary dic = p_variant;
 			sentry_value_t sentry_dic = sentry_value_new_object();
 			const Array &keys = dic.keys();
 			for (int i = 0; i < keys.size(); i++) {
 				const String &key = keys[i];
-				sentry_value_set_by_key(sentry_dic, key.utf8(), variant_to_sentry_value(dic[key]));
+				sentry_value_set_by_key(sentry_dic, key.utf8(), variant_to_sentry_value(dic[key], p_depth + 1));
 			}
 			return sentry_dic;
 		} break;
@@ -40,14 +47,19 @@ sentry_value_t variant_to_sentry_value(const Variant &p_variant) {
 		case Variant::Type::PACKED_VECTOR3_ARRAY:
 		case Variant::Type::PACKED_COLOR_ARRAY:
 		case Variant::Type::PACKED_VECTOR4_ARRAY: {
+			if (p_depth > VARIANT_CONVERSION_MAX_DEPTH) {
+				ERR_PRINT_ONCE("Sentry: Maximum Variant conversion depth reached!");
+				return sentry_value_new_string("[...]");
+			}
+
 			bool oob = false;
 			bool valid = true;
 			int i = 0;
 			sentry_value_t sentry_list = sentry_value_new_list();
 			do {
 				Variant item = p_variant.get_indexed(i++, valid, oob);
 				if (valid) {
-					sentry_value_append(sentry_list, variant_to_sentry_value(item));
+					sentry_value_append(sentry_list, variant_to_sentry_value(item, p_depth + 1));
 				}
 			} while (!oob);
 			return sentry_list;

src/sentry/native/native_util.h

@@ -13,7 +13,7 @@ using namespace godot;
 namespace sentry::native {
 
 // Convert Godot Variant to sentry_value_t.
-sentry_value_t variant_to_sentry_value(const Variant &p_variant);
+sentry_value_t variant_to_sentry_value(const Variant &p_variant, int p_depth = 0);
 
 // Convert PackedStringArray to sentry_value_t (as a list).
 sentry_value_t strings_to_sentry_list(const PackedStringArray &p_strings);