Allocated memory not cleared (only on zephyr?) about wasm-micro-runtime

[TianlongLiang]

Hi, do you have a minimum reproducible test case that I could take a look at?

[sasq64]

After further investigation it seems to happens because data segments are allowed to truncate trailing zeroes and rely on the fact that target memory is zeroed.

Is it possible that mmap()ed memory is zeroed by default on normal systems but not on zephyr ?

[TianlongLiang]

In the Zephyr platform, if you are not explicitly using set_exec_mem_alloc_func, then by default you are using BH_MALLOC(system malloc), you can refer to this file. I think it's worth a try to manually zero out the memory to see whether this is the cause

[sasq64]

Adding a memset() to os_malloc() in zephyr_platform.c fixes the issue.
But most of the time memory is cleared again (like aot_runtime.c / runtime_malloc()) so
I don't think it's the correct fix?

But I am not sure how to find the call to malloc that doesn't clear but should...