Re: [PATCH 1/2] mm/kasan: dump alloc/free stack for page allocator

[Walter Wu]

On Wed, 2019-09-04 at 15:44 +0200, Andrey Konovalov wrote:
> On Wed, Sep 4, 2019 at 8:51 AM Walter Wu <walter-zh.wu@xxxxxxxxxxxx> wrote:
> > +config KASAN_DUMP_PAGE
> > +       bool "Dump the page last stack information"
> > +       depends on KASAN && PAGE_OWNER
> > +       help
> > +         By default, KASAN doesn't record alloc/free stack for page allocator.
> > +         It is difficult to fix up page use-after-free issue.
> > +         This feature depends on page owner to record the last stack of page.
> > +         It is very helpful for solving the page use-after-free or out-of-bound.
> 
> I'm not sure if we need a separate config for this. Is there any
> reason to not have this enabled by default?

PAGE_OWNER need some memory usage, it is not allowed to enable by
default in low RAM device. so I create new feature option and the person
who wants to use it to enable it.

Thanks.
Walter