1 files changed, 32 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/wasm/memory-maximum-clamping.js b/js/src/jit-test/tests/wasm/memory-maximum-clamping.js
new file mode 100644
index 0000000000..dfd1d175d7
--- /dev/null
+++ b/js/src/jit-test/tests/wasm/memory-maximum-clamping.js
@@ -0,0 +1,32 @@
+const MemoryMaxValid = 65536;
+
+// Linking should fail if the imported memory has a higher maximum than required,
+// however if we internally clamp maximum values to an implementation limit
+// and use that for linking we may erroneously accept some modules.
+
+function testLinkFail(importMax, importedMax) {
+  assertErrorMessage(() => {
+    let importedMemory = new WebAssembly.Memory({
+      initial: 0,
+      maximum: importedMax,
+    });
+    wasmEvalText(`(module
+      (memory (import "" "") 0 ${importMax})
+    )`, {"": {"": importedMemory}});
+  }, WebAssembly.LinkError, /incompatible maximum/);
+}
+
+testLinkFail(0, 1);
+testLinkFail(MemoryMaxValid - 1, MemoryMaxValid);
+
+// The type reflection interface for WebAssembly.Memory should not report
+// an internally clamped maximum.
+
+if ('type' in WebAssembly.Memory.prototype) {
+  let memory = new WebAssembly.Memory({
+    initial: 0,
+    maximum: MemoryMaxValid,
+  });
+  let type = memory.type();
+  assertEq(type.maximum, MemoryMaxValid, 'reported memory maximum is not clamped');
+}