2019-09-09 12:46:24

by Maciej S. Szmigiero

Subject: Re: [PATCH] z3fold: fix retry mechanism in page reclaim

On 08.09.2019 15:29, Vitaly Wool wrote:
> z3fold_page_reclaim()'s retry mechanism is broken: on a second
> iteration it will have zhdr from the first one so that zhdr
> is no longer in line with struct page. That leads to crashes when
> the system is stressed.
>
> Fix that by moving zhdr assignment up.
>
> While at it, protect against using already freed handles by using
> own local slots structure in z3fold_page_reclaim().
>
> Reported-by: Markus Linnala <[email protected]>
> Reported-by: Chris Murphy <[email protected]>
> Reported-by: Agustin Dall'Alba <[email protected]>
> Signed-off-by: Vitaly Wool <[email protected]>
> ---

Shouldn't this be CC'ed to stable@ ?

Maciej

2019-09-09 13:38:36

by Vitaly Wool

Subject: Re: [PATCH] z3fold: fix retry mechanism in page reclaim

On Sun, Sep 8, 2019 at 4:56 PM Maciej S. Szmigiero
<[email protected]> wrote:
>
> On 08.09.2019 15:29, Vitaly Wool wrote:
> > z3fold_page_reclaim()'s retry mechanism is broken: on a second
> > iteration it will have zhdr from the first one so that zhdr
> > is no longer in line with struct page. That leads to crashes when
> > the system is stressed.
> >
> > Fix that by moving zhdr assignment up.
> >
> > While at it, protect against using already freed handles by using
> > own local slots structure in z3fold_page_reclaim().
> >
> > Reported-by: Markus Linnala <[email protected]>
> > Reported-by: Chris Murphy <[email protected]>
> > Reported-by: Agustin Dall'Alba <[email protected]>
> > Signed-off-by: Vitaly Wool <[email protected]>
> > ---
>
> Shouldn't this be CC'ed to stable@ ?

I guess :)

Thanks,
Vitaly