Re: [PATCH v4] damon/sysfs: Fix possible memleak on damon_sysfs_add_target.

[Yun Levi]

Thanks :)

And Sorry to my mistake.

On Tue, Sep 27, 2022 at 1:23 AM SeongJae Park <sj@xxxxxxxxxx> wrote:
>
> I forgot removing the closing dot of the subject and making the subject
> lower-case.
>
> On Mon, 26 Sep 2022 16:06:11 +0000 SeongJae Park <sj@xxxxxxxxxx> wrote:
>
> > From: Levi Yun <ppbuk5246@xxxxxxxxx>
> >
> > When damon_sysfs_add_target couldn't find proper task,
> > New allocated damon_target structure isn't registered yet,
> > So, it's impossible to free new allocated one by
> > damon_sysfs_destroy_targets.
> >
> > By calling daemon_add_target as soon as allocating new target, Fix this
>
> Also we should s/daemon/damon/
>
> I will revise and send v5.
>
> > possible memory leak.
> >
> > Fixes: a61ea561c871 ("mm/damon/sysfs: link DAMON for virtual address spaces monitoring")
> > Cc: <stable@xxxxxxxxxxxxxxx> # 5.17.x
> > Signed-off-by: Levi Yun <ppbuk5246@xxxxxxxxx>
> > Reviewed-by: SeongJae Park <sj@xxxxxxxxxx>
> > Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
> > ---
> >
> > Changes from v3
> > (https://lore.kernel.org/damon/20220925234327.26345-1-ppbuk5246@xxxxxxxxx/)
> > - Fix Fixes: tag
> > - Add patch changelog
> >
> > Changes from v2
> > (https://lore.kernel.org/damon/20220925234053.26090-1-ppbuk5246@xxxxxxxxx/)
> > - Add Fixes: and Cc: stable
> >
> > Changes from v1
> > (https://lore.kernel.org/damon/20220925140257.23431-1-ppbuk5246@xxxxxxxxx/)
> > - Do damon_add_target() earlier instead of explicitly freeing the object
> >
> >  mm/damon/sysfs.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
> > index 455215a5c059..9f1219a67e3f 100644
> > --- a/mm/damon/sysfs.c
> > +++ b/mm/damon/sysfs.c
> > @@ -2172,12 +2172,12 @@ static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target,
> >
> >       if (!t)
> >               return -ENOMEM;
> > +     damon_add_target(ctx, t);
> >       if (damon_target_has_pid(ctx)) {
> >               t->pid = find_get_pid(sys_target->pid);
> >               if (!t->pid)
> >                       goto destroy_targets_out;
> >       }
> > -     damon_add_target(ctx, t);
> >       err = damon_sysfs_set_regions(t, sys_target->regions);
> >       if (err)
> >               goto destroy_targets_out;
> > --
> > 2.25.1