[CRIU] [PATCH 1/7] cgroup: add a check for cgroup namespaces

[Pavel Emelyanov]

On 02/18/2016 07:08 PM, Tycho Andersen wrote:
> Signed-off-by: Tycho Andersen <tycho.andersen at canonical.com>
> ---
>  criu/cr-check.c | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/criu/cr-check.c b/criu/cr-check.c
> index 2bb0d9a..854a8a4 100644
> --- a/criu/cr-check.c
> +++ b/criu/cr-check.c
> @@ -820,6 +820,16 @@ static int check_clone_parent_vs_pid()
>  	return 0;
>  }
>  
> +static int check_cgroupns(void)
> +{
> +	if (opts.check_ms_kernel) {
> +		pr_warn("Skipping cgroup namespaces check\n");
> +		return 0;
> +	}
> +
> +	return access("/proc/self/ns/cgroup", F_OK);

Here should come a message that says what's wrong if the access() fails.

> +}
> +
>  static int (*chk_feature)(void);
>  
>  int cr_check(void)
> @@ -876,6 +886,7 @@ int cr_check(void)
>  	ret |= check_aio_remap();
>  	ret |= check_fdinfo_lock();
>  	ret |= check_clone_parent_vs_pid();
> +	ret |= check_cgroupns();
>  
>  out:
>  	if (!ret)
> @@ -949,6 +960,8 @@ int check_add_feature(char *feat)
>  		chk_feature = check_ptrace_dump_seccomp_filters;
>  	else if (!strcmp(feat, "loginuid"))
>  		chk_feature = check_loginuid;
> +	else if (!strcmp(feat, "cgroupns"))
> +		chk_feature = check_cgroupns;
>  	else {
>  		pr_err("Unknown feature %s\n", feat);
>  		return -1;
>