In kobj_ns_current_may_mount the default should be to allow the mount. The test is only for a single kobj_ns_type at a time, and unless there is a reason to prevent it the mounting sysfs should be allowed. Subsystems that are not registered can't have are not involved so can't have a reason to prevent mounting sysfs. This is a bug-fix to commit 7dc5dbc879bd ("sysfs: Restrict mounting sysfs") that came in via the userns tree during the 3.12 merge window.
Unified · Split
| @@ -933,10 +933,7 @@ const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj) · 932 unmodified lines | |||
| 933 | 933 | ||
| 934 | bool kobj_ns_current_may_mount(enum kobj_ns_type type) | 934 | bool kobj_ns_current_may_mount(enum kobj_ns_type type) |
| 935 | { | 935 | { |
| 936 | bool may_mount = false; | 936 | bool may_mount = true; |
| 937 | |||
| 938 | if (type == KOBJ_NS_TYPE_NONE) | ||
| 939 | return true; | ||
| 940 | 937 | ||
| 941 | spin_lock(&kobj_ns_type_lock); | 938 | spin_lock(&kobj_ns_type_lock); |
| 942 | if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) && | 939 | if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) && |