Re: [PATCH v2] security: selinux: allow changing labels for cgroupfs

From: Stephen Smalley
Date: Thu Feb 02 2017 - 14:46:24 EST


On Thu, 2017-02-02 at 16:22 +0100, Antonio Murdaca wrote:
> This patch allows changing labels for cgroup mounts. Previously,
> running
> chcon on cgroupfs would throw an "Operation not supported". This
> patch
> specifically whitelist cgroupfs.
>
> The patch could also allow containers to write only to the systemd
> cgroup
> for instance, while the other cgroups are kept with cgroup_t label.
>
> Signed-off-by: Antonio Murdaca <runcom@xxxxxxxxxx>

Acked-by: Stephen Smalley <sds@xxxxxxxxxxxxx>

> ---
> Changes in v2:
> Â - whitelist cgroup2 fs type
>
> Âsecurity/selinux/hooks.c | 2 ++
> Â1 file changed, 2 insertions(+)
>
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index 3b955c6..2789f0a 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -480,6 +480,8 @@ static int selinux_is_sblabel_mnt(struct
> super_block *sb)
> Â sbsec->behavior == SECURITY_FS_USE_NATIVE ||
> Â /* Special handling. Genfs but also in-core setxattr
> handler */
> Â !strcmp(sb->s_type->name, "sysfs") ||
> + !strcmp(sb->s_type->name, "cgroup") ||
> + !strcmp(sb->s_type->name, "cgroup2") ||
> Â !strcmp(sb->s_type->name, "pstore") ||
> Â !strcmp(sb->s_type->name, "debugfs") ||
> Â !strcmp(sb->s_type->name, "tracefs") ||