From 0f663887ad032954fbed8dd43d2970f51df2177d Mon Sep 17 00:00:00 2001
From: losfair <zhy20000919@hotmail.com>
Date: Mon, 16 Mar 2020 22:49:37 +0800
Subject: [PATCH 1/2] Handle panics from DynamicFunc.

---
 lib/runtime-core-tests/tests/imports.rs | 16 ++++++++++++++++
 lib/runtime-core/src/typed_func.rs      |  9 ++++++++-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/lib/runtime-core-tests/tests/imports.rs b/lib/runtime-core-tests/tests/imports.rs
index e44d5159f8f..f9ac6df9ecf 100644
--- a/lib/runtime-core-tests/tests/imports.rs
+++ b/lib/runtime-core-tests/tests/imports.rs
@@ -77,6 +77,7 @@ fn imported_functions_forms(test: &dyn Fn(&Instance)) {
   (import "env" "callback_fn" (func $callback_fn (type $type)))
   (import "env" "callback_closure" (func $callback_closure (type $type)))
   (import "env" "callback_fn_dynamic" (func $callback_fn_dynamic (type $type)))
+  (import "env" "callback_fn_dynamic_panic" (func $callback_fn_dynamic_panic (type $type)))
   (import "env" "callback_closure_dynamic_0" (func $callback_closure_dynamic_0))
   (import "env" "callback_closure_dynamic_1" (func $callback_closure_dynamic_1 (param i32) (result i32)))
   (import "env" "callback_closure_dynamic_2" (func $callback_closure_dynamic_2 (param i32 i64) (result i64)))
@@ -104,6 +105,10 @@ fn imported_functions_forms(test: &dyn Fn(&Instance)) {
     get_local 0
     call $callback_fn_dynamic)
 
+  (func (export "function_fn_dynamic_panic") (type $type)
+    get_local 0
+    call $callback_fn_dynamic_panic)
+
   (func (export "function_closure_dynamic_0")
     call $callback_closure_dynamic_0)
 
@@ -191,6 +196,12 @@ fn imported_functions_forms(test: &dyn Fn(&Instance)) {
                 callback_fn_dynamic,
             ),
 
+            // Polymorphic function that panics.
+            "callback_fn_dynamic_panic" => DynamicFunc::new(
+                Arc::new(FuncSig::new(vec![Type::I32], vec![Type::I32])),
+                callback_fn_dynamic_panic,
+            ),
+
             // Polymorphic closure “closures”.
             "callback_closure_dynamic_0" => DynamicFunc::new(
                 Arc::new(FuncSig::new(vec![], vec![])),
@@ -325,6 +336,10 @@ fn callback_fn_dynamic(_: &mut vm::Ctx, inputs: &[Value]) -> Vec<Value> {
     }
 }
 
+fn callback_fn_dynamic_panic(_: &mut vm::Ctx, _: &[Value]) -> Vec<Value> {
+    panic!("test");
+}
+
 fn callback_fn_with_vmctx(vmctx: &mut vm::Ctx, n: i32) -> Result<i32, ()> {
     let memory = vmctx.memory(0);
     let shift_: i32 = memory.view()[0].get();
@@ -357,6 +372,7 @@ macro_rules! test {
 test!(test_fn, function_fn(i32) -> i32, (1) == Ok(2));
 test!(test_closure, function_closure(i32) -> i32, (1) == Ok(2));
 test!(test_fn_dynamic, function_fn_dynamic(i32) -> i32, (1) == Ok(2));
+test!(test_fn_dynamic_panic, function_fn_dynamic_panic(i32) -> i32, (1) == Err(RuntimeError(Box::new("test"))));
 test!(
     test_closure_dynamic_0,
     function_closure_dynamic_0(()) -> (),
diff --git a/lib/runtime-core/src/typed_func.rs b/lib/runtime-core/src/typed_func.rs
index 6578042a710..a34960134c2 100644
--- a/lib/runtime-core/src/typed_func.rs
+++ b/lib/runtime-core/src/typed_func.rs
@@ -334,7 +334,14 @@ impl<'a> DynamicFunc<'a> {
                     }
                 })
                 .collect();
-            (ctx.func)(vmctx, &args)
+            match panic::catch_unwind(panic::AssertUnwindSafe(|| (ctx.func)(vmctx, &args))) {
+                Ok(x) => x,
+                Err(e) => {
+                    // At this point, there is an error that needs to be trapped.
+                    drop(args); // Release the Vec which will leak otherwise.
+                    (&*vmctx.module).runnable_module.do_early_trap(e)
+                }
+            }
         }
         unsafe extern "C" fn enter_host_polymorphic_i(
             ctx: *const CallContext,

From 686fe4a1e1907f9efd19e6864c47a8ec20ed38b0 Mon Sep 17 00:00:00 2001
From: losfair <zhy20000919@hotmail.com>
Date: Mon, 16 Mar 2020 22:51:58 +0800
Subject: [PATCH 2/2] Update changelog

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fcfbd3eab48..e73fff47f0e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 ## **[Unreleased]**
 
+- [#1305](https://github.com/wasmerio/wasmer/pull/1305) Handle panics from DynamicFunc.
 - [#1301](https://github.com/wasmerio/wasmer/pull/1301) Update supported stable Rust version to 1.41.1.
 - [#1285](https://github.com/wasmerio/wasmer/pull/1285) Greatly improve errors in `wasmer-interface-types`
 - [#1283](https://github.com/wasmerio/wasmer/pull/1283) Workaround for floating point arguments and return values in `DynamicFunc`s.