On Tue, 3 Sept 2024 at 02:09, Oleg Nesterov <[email protected]> wrote:
>
> but with or without this fix __create_xol_area() also needs
>
> area->xol_mapping.mremap = NULL;
I think the whole thing needs to be zeroed out.
It was always horribly buggy. The close thing just made it more
*obviously* buggy, because closing a vma is a lot more common than
mremap'ing it.
Either use kzalloc(), or do a proper initializer something like this:
- area->xol_mapping.name = "[uprobes]";
- area->xol_mapping.fault = NULL;
- area->xol_mapping.pages = area->pages;
+ area->xol_mapping = (struct vm_special_mapping) {
+ .name = "[uprobes]",
+ .pages = area->pages,
+ .close = uprobe_clear_state,
+ };
which should initialize the struct vm_special_mapping fully.
Linus
