Re: [PATCH] mm: remove duplicated vma->vm_flags check when expanding stack

[Andrew Morton]

On Wed,  6 Sep 2023 10:33:12 +0000 Xiu Jianfeng <xiujianfeng@xxxxxxxxxxxxxxx> wrote:

> expand_upwards() and expand_downwards() will return -EFAULT if VM_GROWSUP
> or VM_GROWSDOWN is not correctly set in vma->vm_flags, however in
> !CONFIG_STACK_GROWSUP case, expand_stack_locked() returns -EINVAL first
> if !(vma->vm_flags & VM_GROWSDOWN) before calling expand_downwards(), to
> keep the consistency with CONFIG_STACK_GROWSUP case, remove this check.

What are the user-visible effects of this change?

Do you believe this fix should be backported into earlier kernel versions?