Clear WASM linear memory on other OSes besides Linux too (#10291)

2026-04-26 23:57:56 +00:00 · 2021-11-18 20:16:38 +09:00
parent 6e424d74ff
commit 15a0bfb0f6
3 changed files with 91 additions and 11 deletions
@@ -699,3 +699,81 @@ fn panic_in_spawned_instance_panics_on_joining_its_result(wasm_method: WasmExecu

 	assert!(format!("{}", error_result).contains("Spawned task"));
 }
+
+test_wasm_execution!(memory_is_cleared_between_invocations);
+fn memory_is_cleared_between_invocations(wasm_method: WasmExecutionMethod) {
+	// This is based on the code generated by compiling a runtime *without*
+	// the `-C link-arg=--import-memory` using the following code and then
+	// disassembling the resulting blob with `wasm-dis`:
+	//
+	// ```
+	// #[no_mangle]
+	// #[cfg(not(feature = "std"))]
+	// pub fn returns_no_bss_mutable_static(_: *mut u8, _: usize) -> u64 {
+	//     static mut COUNTER: usize = 0;
+	//     let output = unsafe {
+	//        COUNTER += 1;
+	//        COUNTER as u64
+	//     };
+	//     sp_core::to_substrate_wasm_fn_return_value(&output)
+	// }
+	// ```
+	//
+	// This results in the BSS section to *not* be emitted, hence the executor has no way
+	// of knowing about the `static` variable's existence, so this test will fail if the linear
+	// memory is not properly cleared between invocations.
+	let binary = wat::parse_str(r#"
+	(module
+	 (type $i32_=>_i32 (func (param i32) (result i32)))
+	 (type $i32_i32_=>_i64 (func (param i32 i32) (result i64)))
+	 (import "env" "ext_allocator_malloc_version_1" (func $ext_allocator_malloc_version_1 (param i32) (result i32)))
+	 (global $__stack_pointer (mut i32) (i32.const 1048576))
+	 (global $global$1 i32 (i32.const 1048580))
+	 (global $global$2 i32 (i32.const 1048592))
+	 (memory $0 17)
+	 (export "memory" (memory $0))
+	 (export "returns_no_bss_mutable_static" (func $returns_no_bss_mutable_static))
+	 (export "__data_end" (global $global$1))
+	 (export "__heap_base" (global $global$2))
+	 (func $returns_no_bss_mutable_static (param $0 i32) (param $1 i32) (result i64)
+	  (local $2 i32)
+	  (local $3 i32)
+	  (i32.store offset=1048576
+	   (i32.const 0)
+	   (local.tee $2
+	    (i32.add
+	     (i32.load offset=1048576 (i32.const 0))
+	     (i32.const 1)
+	    )
+	   )
+	  )
+	  (i64.store
+	   (local.tee $3
+	    (call $ext_allocator_malloc_version_1 (i32.const 8))
+	   )
+	   (i64.extend_i32_u (local.get $2))
+	  )
+	  (i64.or
+	   (i64.extend_i32_u (local.get $3))
+	   (i64.const 34359738368)
+	  )
+	 )
+	)"#).unwrap();
+
+	let runtime = crate::wasm_runtime::create_wasm_runtime_with_code(
+		wasm_method,
+		1024,
+		RuntimeBlob::uncompress_if_needed(&binary[..]).unwrap(),
+		HostFunctions::host_functions(),
+		true,
+		None,
+	)
+	.unwrap();
+
+	let mut instance = runtime.new_instance().unwrap();
+	let res = instance.call_export("returns_no_bss_mutable_static", &[0]).unwrap();
+	assert_eq!(1, u64::decode(&mut &res[..]).unwrap());
+
+	let res = instance.call_export("returns_no_bss_mutable_static", &[0]).unwrap();
+	assert_eq!(1, u64::decode(&mut &res[..]).unwrap());
+}