Memory Leak(?) problem with usermode harness

Hi, I looked at the example of the KAFL UserMode harness and used the code below to fuzz Defender. By the way, after some time, QEMU will be shut down due to low memory. (Actual Ram 64gb, Swap file 50gb) This is quite weird. As far as I know, fuzzer is returning qemu to the time it called LOCK Hypercall, and working again, so suppose it's not affected by functions such as memory free or freelibrary.(because it will be restore to when I called Lock Hypercall) And no payload will have more than 500mb of memory usage on the host(on my real compute). Why is this happening? Below is my code.
It's weird because I didn't get this memory related problem when I tested the Windows driver and just as an example. Am I doing something wrong?

my parameter was : kafl fuzz -workdir ./work --seed-dir ./seed --redqueen -p 24

dunno why but if i paste my code to this issue section directly, then indent make weird. So I paste it to pastebin