From 6ed00f1af2916c27660e2a14bc63ace74459a27d Mon Sep 17 00:00:00 2001
From: Alexey Andreev <konsoletyper@gmail.com>
Date: Mon, 28 Oct 2019 13:59:03 +0300
Subject: [PATCH] C/Wasm: fix heap corruption when GC hits on initializing
 stack trace of exception

---
 .../java/org/teavm/classlib/java/lang/TThrowable.java     | 8 +-------
 .../lowlevel/ExceptionHandlingShadowStackContributor.java | 8 +++++++-
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/classlib/src/main/java/org/teavm/classlib/java/lang/TThrowable.java b/classlib/src/main/java/org/teavm/classlib/java/lang/TThrowable.java
index 7c72f80aa..428d2a588 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/lang/TThrowable.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/lang/TThrowable.java
@@ -22,7 +22,6 @@ import org.teavm.classlib.java.util.TArrays;
 import org.teavm.interop.Remove;
 import org.teavm.interop.Rename;
 import org.teavm.interop.Superclass;
-import org.teavm.interop.Unmanaged;
 import org.teavm.runtime.ExceptionHandling;
 
 @Superclass("java.lang.Object")
@@ -104,16 +103,11 @@ public class TThrowable extends RuntimeException {
     @Override
     public Throwable fillInStackTrace() {
         if (PlatformDetector.isLowLevel()) {
-            stackTrace = fillInStackTraceLowLevel();
+            stackTrace = (TStackTraceElement[]) (Object) ExceptionHandling.fillStackTrace();
         }
         return this;
     }
 
-    @Unmanaged
-    private static TStackTraceElement[] fillInStackTraceLowLevel() {
-        return (TStackTraceElement[]) (Object) ExceptionHandling.fillStackTrace();
-    }
-
     @Rename("getMessage")
     public String getMessage0() {
         return message;
diff --git a/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java b/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java
index 592d20372..4979946f9 100644
--- a/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java
+++ b/core/src/main/java/org/teavm/model/lowlevel/ExceptionHandlingShadowStackContributor.java
@@ -67,6 +67,8 @@ import org.teavm.runtime.ExceptionHandling;
 import org.teavm.runtime.ShadowStack;
 
 public class ExceptionHandlingShadowStackContributor {
+    private static final MethodReference FILL_STACK_TRACE = new MethodReference(ExceptionHandling.class,
+            "fillStackTrace", StackTraceElement[].class);
     private Characteristics characteristics;
     private List<CallSiteDescriptor> callSites;
     private BasicBlock defaultExceptionHandler;
@@ -281,7 +283,11 @@ public class ExceptionHandlingShadowStackContributor {
                 || insn instanceof NullCheckInstruction || insn instanceof BoundCheckInstruction) {
             return true;
         } else if (insn instanceof InvokeInstruction) {
-            return isManagedMethodCall(characteristics, ((InvokeInstruction) insn).getMethod());
+            MethodReference method = ((InvokeInstruction) insn).getMethod();
+            if (method.equals(FILL_STACK_TRACE)) {
+                return true;
+            }
+            return isManagedMethodCall(characteristics, method);
         }
         return false;
     }