1 files changed, 26 insertions, 1 deletions

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 0dfc7324c789..9fcdaa705b6c 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2346,11 +2346,26 @@ static int cgroup_rename(struct kernfs_node *kn, struct kernfs_node *new_parent,
         return ret;
 }
 
+/* set uid and gid of cgroup dirs and files to that of the creator */
+static int cgroup_kn_set_ugid(struct kernfs_node *kn)
+{
+        struct iattr iattr = { .ia_valid = ATTR_UID | ATTR_GID,
+                               .ia_uid = current_fsuid(),
+                               .ia_gid = current_fsgid(), };
+
+        if (uid_eq(iattr.ia_uid, GLOBAL_ROOT_UID) &&
+            gid_eq(iattr.ia_gid, GLOBAL_ROOT_GID))
+                return 0;
+
+        return kernfs_setattr(kn, &iattr);
+}
+
 static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft)
 {
         char name[CGROUP_FILE_NAME_MAX];
         struct kernfs_node *kn;
         struct lock_class_key *key = NULL;
+        int ret;
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
         key = &cft->lockdep_key;
@@ -2358,7 +2373,13 @@ static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft)
         kn = __kernfs_create_file(cgrp->kn, cgroup_file_name(cgrp, cft, name),
                                   cgroup_file_mode(cft), 0, cft->kf_ops, cft,
                                   NULL, false, key);
-        return PTR_ERR_OR_ZERO(kn);
+        if (IS_ERR(kn))
+                return PTR_ERR(kn);
+
+        ret = cgroup_kn_set_ugid(kn);
+        if (ret)
+                kernfs_remove(kn);
+        return ret;
 }
 
 /**
@@ -3753,6 +3774,10 @@ static long cgroup_create(struct cgroup *parent, const char *name,
          */
         idr_replace(&root->cgroup_idr, cgrp, cgrp->id);
 
+        err = cgroup_kn_set_ugid(kn);
+        if (err)
+                goto err_destroy;
+
         err = cgroup_addrm_files(cgrp, cgroup_base_files, true);
         if (err)
                 goto err_destroy;