Merge branch 'for-4.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull more cgroup updates from Tejun Heo:
 "I forgot to include the patches which got applied to for-4.7-fixes
  late during last cycle.

  Eric's three patches fix bugs introduced with the namespace support"

* 'for-4.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroupns: Only allow creation of hierarchies in the initial cgroup namespace
  cgroupns: Close race between cgroup_post_fork and copy_cgroup_ns
  cgroupns: Fix the locking in copy_cgroup_ns
This commit is contained in:
Linus Torvalds 2016-07-29 14:29:04 -07:00
commit 574c7e2333

View File

@ -2209,12 +2209,8 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
goto out_unlock;
}
/*
* We know this subsystem has not yet been bound. Users in a non-init
* user namespace may only mount hierarchies with no bound subsystems,
* i.e. 'none,name=user1'
*/
if (!opts.none && !capable(CAP_SYS_ADMIN)) {
/* Hierarchies may only be created in the initial cgroup namespace. */
if (ns != &init_cgroup_ns) {
ret = -EPERM;
goto out_unlock;
}
@ -2956,6 +2952,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk)
int retval = 0;
mutex_lock(&cgroup_mutex);
percpu_down_write(&cgroup_threadgroup_rwsem);
for_each_root(root) {
struct cgroup *from_cgrp;
@ -2970,6 +2967,7 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk)
if (retval)
break;
}
percpu_up_write(&cgroup_threadgroup_rwsem);
mutex_unlock(&cgroup_mutex);
return retval;
@ -4337,6 +4335,8 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from)
mutex_lock(&cgroup_mutex);
percpu_down_write(&cgroup_threadgroup_rwsem);
/* all tasks in @from are being moved, all csets are source */
spin_lock_irq(&css_set_lock);
list_for_each_entry(link, &from->cset_links, cset_link)
@ -4365,6 +4365,7 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from)
} while (task && !ret);
out_err:
cgroup_migrate_finish(&preloaded_csets);
percpu_up_write(&cgroup_threadgroup_rwsem);
mutex_unlock(&cgroup_mutex);
return ret;
}
@ -6339,14 +6340,11 @@ struct cgroup_namespace *copy_cgroup_ns(unsigned long flags,
if (!ns_capable(user_ns, CAP_SYS_ADMIN))
return ERR_PTR(-EPERM);
mutex_lock(&cgroup_mutex);
/* It is not safe to take cgroup_mutex here */
spin_lock_irq(&css_set_lock);
cset = task_css_set(current);
get_css_set(cset);
spin_unlock_irq(&css_set_lock);
mutex_unlock(&cgroup_mutex);
new_ns = alloc_cgroup_ns();
if (IS_ERR(new_ns)) {