From: Zoltan Varga <vargaz@gmail.com>
Date: Tue, 4 Aug 2020 22:18:21 +0000 (-0400)
Subject: [wasm] Make mono_wasm_get_obj_type () GC safe by doing all object access before calli... 
X-Git-Tag: submit/tizen/20210909.063632~6225
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7d3b804b6078a647835bfaf697369109855093b5;p=platform%2Fupstream%2Fdotnet%2Fruntime.git

[wasm] Make mono_wasm_get_obj_type () GC safe by doing all object access before calling into the runtime. (#40312)

Part of the fix for https://github.com/dotnet/runtime/issues/40132.
---

diff --git a/src/mono/wasm/runtime/driver.c b/src/mono/wasm/runtime/driver.c
index fec7260..0400c39 100644
--- a/src/mono/wasm/runtime/driver.c
+++ b/src/mono/wasm/runtime/driver.c
@@ -587,6 +587,11 @@ mono_wasm_get_obj_type (MonoObject *obj)
 	if (!obj)
 		return 0;
 
+	/* Process obj before calling into the runtime, class_from_name () can invoke managed code */
+	MonoClass *klass = mono_object_get_class (obj);
+	MonoType *type = mono_class_get_type (klass);
+	obj = NULL;
+
 	if (!datetime_class)
 		datetime_class = mono_class_from_name (mono_get_corlib(), "System", "DateTime");
 	if (!datetimeoffset_class)
@@ -598,9 +603,6 @@ mono_wasm_get_obj_type (MonoObject *obj)
 	if (!safehandle_class)
 		safehandle_class = mono_class_from_name (mono_get_corlib(), "System.Runtime.InteropServices", "SafeHandle");
 
-	MonoClass *klass = mono_object_get_class (obj);
-	MonoType *type = mono_class_get_type (klass);
-
 	switch (mono_type_get_type (type)) {
 	// case MONO_TYPE_CHAR: prob should be done not as a number?
 	case MONO_TYPE_BOOLEAN: