Hi Luigi, Stefano, Thanks for taking a look.
Luigi — nothing fancy, I was just reading sysctl handlers and noticed that __vsock_net_mode_string() bails early on a zero-length write without touching new_mode. Since the child mode can only be set once, an empty write that sneaks through locks it with whatever was on the stack. CONFIG_INIT_STACK_ALL_ZERO hides the whole thing, which is probably why nobody hit it in practice. Stefano — yeah, makes more sense to bail before calling the helper at all. Fixed in v3, and I added the CCs I missed. Cheers, Aldo
