Fix for a soundness bug around scope, don't allow callback parameters to escape

Also includes other fixes for compiletest_rs failures, and a small reorg of tests

8 files changed, 152 insertions, 104 deletions

diff --git a/src/scope.rs b/src/scope.rs
index 476b5c1..58f440f 100644
--- a/src/scope.rs
+++ b/src/scope.rs
@@ -61,6 +61,7 @@ impl<'scope> Scope<'scope> {
         A: FromLuaMulti<'callback>,
         R: ToLuaMulti<'callback>,
         F: 'scope + Fn(&'callback Lua, A) -> Result<R>,
+        'scope: 'callback,
     {
         unsafe {
             let f = Box::new(move |lua, args| {
@@ -106,6 +107,7 @@ impl<'scope> Scope<'scope> {
         A: FromLuaMulti<'callback>,
         R: ToLuaMulti<'callback>,
         F: 'scope + FnMut(&'callback Lua, A) -> Result<R>,
+        'scope: 'callback,
     {
         let func = RefCell::new(func);
         self.create_function(move |lua, args| {
diff --git a/src/tests/mod.rs b/src/tests/mod.rs
index deed3bd..196bc45 100644
--- a/src/tests/mod.rs
+++ b/src/tests/mod.rs
@@ -1,21 +1,17 @@
 mod function;
+mod scope;
 mod string;
 mod table;
 mod thread;
 mod types;
 mod userdata;
 
-use std::cell::Cell;
 use std::iter::FromIterator;
 use std::panic::catch_unwind;
-use std::rc::Rc;
 use std::sync::Arc;
 use std::{error, fmt};
 
-use {
-    Error, ExternalError, Function, Lua, Nil, Result, String, Table, UserData, UserDataMethods,
-    Value, Variadic,
-};
+use {Error, ExternalError, Function, Lua, Nil, Result, String, Table, UserData, Value, Variadic};
 
 #[test]
 fn test_load() {
@@ -621,102 +617,6 @@ fn test_mismatched_registry_key() {
 }
 
 #[test]
-fn scope_func() {
-    let lua = Lua::new();
-
-    let rc = Rc::new(Cell::new(0));
-    lua.scope(|scope| {
-        let r = rc.clone();
-        let f = scope
-            .create_function(move |_, ()| {
-                r.set(42);
-                Ok(())
-            })
-            .unwrap();
-        lua.globals().set("bad", f.clone()).unwrap();
-        f.call::<_, ()>(()).unwrap();
-        assert_eq!(Rc::strong_count(&rc), 2);
-    });
-    assert_eq!(rc.get(), 42);
-    assert_eq!(Rc::strong_count(&rc), 1);
-
-    match lua
-        .globals()
-        .get::<_, Function>("bad")
-        .unwrap()
-        .call::<_, ()>(())
-    {
-        Err(Error::CallbackError { .. }) => {}
-        r => panic!("improper return for destructed function: {:?}", r),
-    };
-}
-
-#[test]
-fn scope_drop() {
-    let lua = Lua::new();
-
-    struct MyUserdata(Rc<()>);
-    impl UserData for MyUserdata {
-        fn add_methods(methods: &mut UserDataMethods<Self>) {
-            methods.add_method("method", |_, _, ()| Ok(()));
-        }
-    }
-
-    let rc = Rc::new(());
-
-    lua.scope(|scope| {
-        lua.globals()
-            .set(
-                "test",
-                scope.create_userdata(MyUserdata(rc.clone())).unwrap(),
-            )
-            .unwrap();
-        assert_eq!(Rc::strong_count(&rc), 2);
-    });
-    assert_eq!(Rc::strong_count(&rc), 1);
-
-    match lua.exec::<()>("test:method()", None) {
-        Err(Error::CallbackError { .. }) => {}
-        r => panic!("improper return for destructed userdata: {:?}", r),
-    };
-}
-
-#[test]
-fn scope_capture() {
-    let lua = Lua::new();
-
-    let mut i = 0;
-    lua.scope(|scope| {
-        scope
-            .create_function_mut(|_, ()| {
-                i = 42;
-                Ok(())
-            })
-            .unwrap()
-            .call::<_, ()>(())
-            .unwrap();
-    });
-    assert_eq!(i, 42);
-}
-
-#[test]
-fn outer_lua_access() {
-    let lua = Lua::new();
-    let table = lua.create_table().unwrap();
-    lua.scope(|scope| {
-        scope
-            .create_function_mut(|_, ()| {
-                table.set("a", "b").unwrap();
-                Ok(())
-            })
-            .unwrap()
-            .call::<_, ()>(())
-            .unwrap();
-    });
-    assert_eq!(table.get::<_, String>("a").unwrap(), "b");
-}
-
-#[test]
 fn too_many_returns() {
     let lua = Lua::new();
     let f = lua
diff --git a/src/tests/scope.rs b/src/tests/scope.rs
new file mode 100644
index 0000000..1e4c255
--- /dev/null
+++ b/src/tests/scope.rs
@@ -0,0 +1,100 @@
+use std::cell::Cell;
+use std::rc::Rc;
+
+use {Error, Function, Lua, String, UserData, UserDataMethods};
+
+#[test]
+fn scope_func() {
+    let lua = Lua::new();
+
+    let rc = Rc::new(Cell::new(0));
+    lua.scope(|scope| {
+        let r = rc.clone();
+        let f = scope
+            .create_function(move |_, ()| {
+                r.set(42);
+                Ok(())
+            })
+            .unwrap();
+        lua.globals().set("bad", f.clone()).unwrap();
+        f.call::<_, ()>(()).unwrap();
+        assert_eq!(Rc::strong_count(&rc), 2);
+    });
+    assert_eq!(rc.get(), 42);
+    assert_eq!(Rc::strong_count(&rc), 1);
+
+    match lua
+        .globals()
+        .get::<_, Function>("bad")
+        .unwrap()
+        .call::<_, ()>(())
+    {
+        Err(Error::CallbackError { .. }) => {}
+        r => panic!("improper return for destructed function: {:?}", r),
+    };
+}
+
+#[test]
+fn scope_drop() {
+    let lua = Lua::new();
+
+    struct MyUserdata(Rc<()>);
+    impl UserData for MyUserdata {
+        fn add_methods(methods: &mut UserDataMethods<Self>) {
+            methods.add_method("method", |_, _, ()| Ok(()));
+        }
+    }
+
+    let rc = Rc::new(());
+
+    lua.scope(|scope| {
+        lua.globals()
+            .set(
+                "test",
+                scope.create_userdata(MyUserdata(rc.clone())).unwrap(),
+            )
+            .unwrap();
+        assert_eq!(Rc::strong_count(&rc), 2);
+    });
+    assert_eq!(Rc::strong_count(&rc), 1);
+
+    match lua.exec::<()>("test:method()", None) {
+        Err(Error::CallbackError { .. }) => {}
+        r => panic!("improper return for destructed userdata: {:?}", r),
+    };
+}
+
+#[test]
+fn scope_capture() {
+    let lua = Lua::new();
+
+    let mut i = 0;
+    lua.scope(|scope| {
+        scope
+            .create_function_mut(|_, ()| {
+                i = 42;
+                Ok(())
+            })
+            .unwrap()
+            .call::<_, ()>(())
+            .unwrap();
+    });
+    assert_eq!(i, 42);
+}
+
+#[test]
+fn outer_lua_access() {
+    let lua = Lua::new();
+    let table = lua.create_table().unwrap();
+    lua.scope(|scope| {
+        scope
+            .create_function_mut(|_, ()| {
+                table.set("a", "b").unwrap();
+                Ok(())
+            })
+            .unwrap()
+            .call::<_, ()>(())
+            .unwrap();
+    });
+    assert_eq!(table.get::<_, String>("a").unwrap(), "b");
+}
diff --git a/tests/compile-fail/not_refunwindsafe.rs b/tests/compile-fail/not_refunwindsafe.rs
index 08de5de..55a3189 100644
--- a/tests/compile-fail/not_refunwindsafe.rs
+++ b/tests/compile-fail/not_refunwindsafe.rs
@@ -7,5 +7,6 @@ use rlua::*;
 fn main() {
     let lua = Lua::new();
     let _ = catch_unwind(|| lua.create_table().unwrap());
-    //~^ error: the trait bound `std::cell::UnsafeCell<()>: std::panic::RefUnwindSafe` is not satisfied in `rlua::Lua`
+    //~^ error: the type `std::cell::UnsafeCell<()>` may contain interior mutability and a reference
+    // may not be safely transferrable across a catch_unwind boundary
 }
diff --git a/tests/compile-fail/ref_not_unwindsafe.rs b/tests/compile-fail/ref_not_unwindsafe.rs
index 5debd16..19d64a6 100644
--- a/tests/compile-fail/ref_not_unwindsafe.rs
+++ b/tests/compile-fail/ref_not_unwindsafe.rs
@@ -8,5 +8,6 @@ fn main() {
     let lua = Lua::new();
     let table = lua.create_table().unwrap();
     let _ = catch_unwind(move || table.set("a", "b").unwrap());
-    //~^ error: the trait bound `std::cell::UnsafeCell<()>: std::panic::RefUnwindSafe` is not satisfied in `rlua::Lua`
+    //~^ error: the type `std::cell::UnsafeCell<()>` may contain interior mutability and a reference
+    // may not be safely transferrable across a catch_unwind boundary
 }
diff --git a/tests/compile-fail/scope_callback_escape.rs b/tests/compile-fail/scope_callback_escape.rs
new file mode 100644
index 0000000..2da9d61
--- /dev/null
+++ b/tests/compile-fail/scope_callback_escape.rs
@@ -0,0 +1,22 @@
+extern crate rlua;
+
+use rlua::*;
+
+fn main() {
+    struct Test {
+        field: i32,
+    }
+
+    let lua = Lua::new();
+    let mut outer: Option<Table> = None;
+    lua.scope(|scope| {
+        let f = scope
+            .create_function_mut(|_, t: Table| {
+                outer = Some(t);
+                //~^ error: `*outer` does not live long enough
+                Ok(())
+            })
+            .unwrap();
+        f.call::<_, ()>(lua.create_table()).unwrap();
+    });
+}
diff --git a/tests/compile-fail/scope_callback_inner.rs b/tests/compile-fail/scope_callback_inner.rs
new file mode 100644
index 0000000..6e95a9e
--- /dev/null
+++ b/tests/compile-fail/scope_callback_inner.rs
@@ -0,0 +1,22 @@
+extern crate rlua;
+
+use rlua::*;
+
+fn main() {
+    struct Test {
+        field: i32,
+    }
+
+    let lua = Lua::new();
+    lua.scope(|scope| {
+        let mut inner: Option<Table> = None;
+        let f = scope
+            .create_function_mut(|_, t: Table| {
+                inner = Some(t);
+                //~^ error: `inner` does not live long enough
+                Ok(())
+            })
+            .unwrap();
+        f.call::<_, ()>(lua.create_table()).unwrap();
+    });
+}
diff --git a/tests/compile-fail/scope_escape.rs b/tests/compile-fail/scope_handle_escape.rs
index 18be7db..18be7db 100644
--- a/tests/compile-fail/scope_escape.rs
+++ b/tests/compile-fail/scope_handle_escape.rs