On Sat, 2024-02-03 at 00:05 +0000, Mark Brown wrote:
> + if (args->shadow_stack) {
> + addr = args->shadow_stack;
> + size = args->shadow_stack_size;
>
> - size = adjust_shstk_size(stack_size);
> - addr = alloc_shstk(0, size, 0, false);
> - if (IS_ERR_VALUE(addr))
> - return addr;
> + /* There should be a valid token at the top of the
> stack. */
> + if (!shstk_consume_token(tsk, addr + size -
> sizeof(u64)))
> + return (unsigned long)ERR_PTR(-EINVAL);
I think for this case, it needs:
shstk->base = 0;
shstk->size = 0;
To prevent trying to free the parents shadow stack when the child
exits.
