[PATCH v7 2/9] seccomp: split filter prep from check and apply

[David Drysdale]

On Mon, Jun 23, 2014 at 02:58:06PM -0700, Kees Cook wrote:
> In preparation for adding seccomp locking, move filter creation away
> from where it is checked and applied. This will allow for locking where
> no memory allocation is happening. The validation, filter attachment,
> and seccomp mode setting can all happen under the future locks.
> 
> Signed-off-by: Kees Cook <keescook at chromium.org>
> ---
>  kernel/seccomp.c |   97 +++++++++++++++++++++++++++++++++++++-----------------
>  1 file changed, 67 insertions(+), 30 deletions(-)
> 
> diff --git a/kernel/seccomp.c b/kernel/seccomp.c
> index afb916c7e890..edc8c79ed16d 100644
> --- a/kernel/seccomp.c
> +++ b/kernel/seccomp.c
> @@ -515,6 +551,7 @@ static long seccomp_set_mode(unsigned long seccomp_mode, char __user *filter)
>  	current->seccomp.mode = seccomp_mode;
>  	set_thread_flag(TIF_SECCOMP);
>  out:
> +	seccomp_filter_free(prepared);
>  	return ret;
>  }

I think this needs to be inside #ifdef CONFIG_SECCOMP_FILTER to match
the definition of seccomp_filter_free:

../kernel/seccomp.c:554:2: error: implicit declaration of function ‘seccomp_filter_free’ [-Werror=implicit-function-declaration]