Re: [PATCH v2 5/8] memcg: accounting for fasync_cache

[Shakeel Butt <shakeelb@google.com>]

On Mon, Mar 15, 2021 at 5:23 AM Vasily Averin <vvs@virtuozzo.com> wrote:
>
> unprivileged user inside memcg-limited container can trigger
> creation of huge number of non-accounted fasync_struct objects

You need to make each patch of this series self-contained by including
the motivation behind the series (just one or two sentences). For
example, for this patch include what's the potential impact of these
huge numbers of unaccounted fasync_struct objects?

> ---
>  fs/fcntl.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/fcntl.c b/fs/fcntl.c
> index dfc72f1..7941559 100644
> --- a/fs/fcntl.c
> +++ b/fs/fcntl.c
> @@ -1049,7 +1049,8 @@ static int __init fcntl_init(void)
>                         __FMODE_EXEC | __FMODE_NONOTIFY));
>
>         fasync_cache = kmem_cache_create("fasync_cache",
> -               sizeof(struct fasync_struct), 0, SLAB_PANIC, NULL);
> +                                        sizeof(struct fasync_struct), 0,
> +                                        SLAB_PANIC | SLAB_ACCOUNT, NULL);
>         return 0;
>  }
>
> --
> 1.8.3.1
>