Basic code can crash the whole Node.js process

[tmisirpash]

Here's a an example that causes an OOM and an ungraceful exit with isolated-vm:

const ivm = require("isolated-vm");

const isolate = new ivm.Isolate({memoryLimit: 512});
const context = isolate.createContextSync();

context.evalClosureSync(`
        const arrayBuffer = new ArrayBuffer(100 * 1024 * 1024);

        let view = new Array(arrayBuffer.byteLength);
        let array = new Uint8Array(arrayBuffer);
        let i = view.length;
        while (i--) {
            view[i] = array[i];
        }
`);

Output:

<--- JS stacktrace --->

CALL_AND_RETRY_LAST
is_heap_oom = 1


<--- Heap statistics --->
total_heap_size = 203489280
total_heap_size_executable = 262144
total_physical_size = 201801728
total_available_size = 360626944
used_heap_size = 201638712
heap_size_limit = 562036736
malloced_memory = 49256
peak_malloced_memory = 254976
does_zap_garbage = 0
Abort trap: 6

Would appreciate some help in understanding whether this is a bug somewhere in isolated-vm or V8 and how a Node.js process can be more resilient against failures like this.

[tmisirpash]

What's interesting here is that the used heap size is 200 MB (I am duplicating a 100 MB array buffer, so this seems expected). This is less than half of the memory limit, but we still have a heap OOM.

[laverdet]

Yes that's a strange one. I don't have a solution for you at this time.