cgroup: update cgroup_create() failure path
cgroup_create() was ignoring failure of cgroupfs files. Update it
such that, if file creation fails, it rolls back by calling
cgroup_destroy_locked() and returns failure.
Note that error out goto labels are renamed. The labels are a bit
confusing but will become better w/ later cgroup operation renames.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index c53f42e..027b66e 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4107,7 +4107,7 @@
*/
if (!cgroup_lock_live_group(parent)) {
err = -ENODEV;
- goto err_free;
+ goto err_free_cgrp;
}
/* Grab a reference on the superblock so the hierarchy doesn't
@@ -4135,13 +4135,13 @@
css = ss->create(cgrp);
if (IS_ERR(css)) {
err = PTR_ERR(css);
- goto err_destroy;
+ goto err_free_all;
}
init_cgroup_css(css, ss, cgrp);
if (ss->use_id) {
err = alloc_css_id(ss, parent, cgrp);
if (err)
- goto err_destroy;
+ goto err_free_all;
}
/* At error, ->destroy() callback has to free assigned ID. */
if (clone_children(parent) && ss->post_clone)
@@ -4164,7 +4164,7 @@
*/
err = cgroup_create_file(dentry, S_IFDIR | mode, sb);
if (err < 0)
- goto err_destroy;
+ goto err_free_all;
lockdep_assert_held(&dentry->d_inode->i_mutex);
/* allocation complete, commit to creation */
@@ -4183,14 +4183,15 @@
}
err = cgroup_populate_dir(cgrp, true, root->subsys_mask);
- /* If err < 0, we have a half-filled directory - oh well ;) */
+ if (err)
+ goto err_destroy;
mutex_unlock(&cgroup_mutex);
mutex_unlock(&cgrp->dentry->d_inode->i_mutex);
return 0;
-err_destroy:
+err_free_all:
for_each_subsys(root, ss) {
if (cgrp->subsys[ss->subsys_id])
ss->destroy(cgrp);
@@ -4198,9 +4199,15 @@
mutex_unlock(&cgroup_mutex);
/* Release the reference count that we took on the superblock */
deactivate_super(sb);
-err_free:
+err_free_cgrp:
kfree(cgrp);
return err;
+
+err_destroy:
+ cgroup_destroy_locked(cgrp);
+ mutex_unlock(&cgroup_mutex);
+ mutex_unlock(&dentry->d_inode->i_mutex);
+ return err;
}
static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)