From: Chen Zhou <chenzhou10@xxxxxxxxxx> commit 61e960b07b637f0295308ad91268501d744c21b5 upstream. When mounting a cgroup hierarchy with disabled controller in cgroup v1, all available controllers will be attached. For example, boot with cgroup_no_v1=cpu or cgroup_disable=cpu, and then mount with "mount -t cgroup -ocpu cpu /sys/fs/cgroup/cpu", then all enabled controllers will be attached except cpu. Fix this by adding disabled controller check in cgroup1_parse_param(). If the specified controller is disabled, just return error with information "Disabled controller xx" rather than attaching all the other enabled controllers. Fixes: f5dfb5315d34 ("cgroup: take options parsing into ->parse_monolithic()") Signed-off-by: Chen Zhou <chenzhou10@xxxxxxxxxx> Reviewed-by: Zefan Li <lizefan.x@xxxxxxxxxxxxx> Reviewed-by: Michal Koutný <mkoutny@xxxxxxxx> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Luiz Capitulino <luizcap@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/cgroup/cgroup-v1.c | 3 +++ 1 file changed, 3 insertions(+) --- a/kernel/cgroup/cgroup-v1.c +++ b/kernel/cgroup/cgroup-v1.c @@ -944,6 +944,9 @@ int cgroup1_parse_param(struct fs_contex for_each_subsys(ss, i) { if (strcmp(param->key, ss->legacy_name)) continue; + if (!cgroup_ssid_enabled(i) || cgroup1_ssid_disabled(i)) + return invalf(fc, "Disabled controller '%s'", + param->key); ctx->subsys_mask |= (1 << i); return 0; }