Re: [PATCH v7 2/6] seccomp: make get_nth_filter available outside of CHECKPOINT_RESTORE

[Kees Cook]

On Thu, Sep 27, 2018 at 8:11 AM, Tycho Andersen <tycho@xxxxxxxx> wrote:
> In the next commit we'll use this same mnemonic to get a listener for the
> nth filter, so we need it available outside of CHECKPOINT_RESTORE in the
> USER_NOTIFICATION case as well.
>
> v2: new in v2
> v3: no changes
> v4: no changes
> v5: switch to CHECKPOINT_RESTORE || USER_NOTIFICATION to avoid warning when
>     only CONFIG_SECCOMP_FILTER is enabled.
> v7: drop USER_NOTIFICATION bits
>
> Signed-off-by: Tycho Andersen <tycho@xxxxxxxx>
> CC: Kees Cook <keescook@xxxxxxxxxxxx>
> CC: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
> CC: Oleg Nesterov <oleg@xxxxxxxxxx>
> CC: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
> CC: "Serge E. Hallyn" <serge@xxxxxxxxxx>
> CC: Christian Brauner <christian.brauner@xxxxxxxxxx>
> CC: Tyler Hicks <tyhicks@xxxxxxxxxxxxx>
> CC: Akihiro Suda <suda.akihiro@xxxxxxxxxxxxx>
> ---
>  kernel/seccomp.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/seccomp.c b/kernel/seccomp.c
> index fa6fe9756c80..44a31ac8373a 100644
> --- a/kernel/seccomp.c
> +++ b/kernel/seccomp.c
> @@ -1158,7 +1158,7 @@ long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter)
>         return do_seccomp(op, 0, uargs);
>  }
>
> -#if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE)
> +#if defined(CONFIG_SECCOMP_FILTER)
>  static struct seccomp_filter *get_nth_filter(struct task_struct *task,
>                                              unsigned long filter_off)
>  {
> @@ -1205,6 +1205,7 @@ static struct seccomp_filter *get_nth_filter(struct task_struct *task,
>         return filter;
>  }
>
> +#if defined(CONFIG_CHECKPOINT_RESTORE)
>  long seccomp_get_filter(struct task_struct *task, unsigned long filter_off,
>                         void __user *data)
>  {
> @@ -1277,7 +1278,8 @@ long seccomp_get_metadata(struct task_struct *task,
>         __put_seccomp_filter(filter);
>         return ret;
>  }
> -#endif
> +#endif /* CONFIG_CHECKPOINT_RESTORE */
> +#endif /* CONFIG_SECCOMP_FILTER */
>
>  #ifdef CONFIG_SYSCTL

Yup, looks fine.

-Kees

-- 
Kees Cook
Pixel Security