[PATCH 5/6] mm/hugetlb: fix sysfs group leak in hugetlb_unregister_node()
From: Miaohe Lin
Date: Tue Aug 16 2022 - 09:06:44 EST
The sysfs group per_node_hstate_attr_group and hstate_demote_attr_group
when h->demote_order != 0 are created in hugetlb_register_node(). But
these sysfs groups are not removed when unregister the node, thus sysfs
group is leaked. Using sysfs_remove_group() to fix this issue.
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
---
mm/hugetlb.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b69d7808f457..e1356ad57087 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3850,12 +3850,18 @@ static int hugetlb_sysfs_add_hstate(struct hstate *h, struct kobject *parent,
}
if (h->demote_order) {
- if (sysfs_create_group(hstate_kobjs[hi],
- &hstate_demote_attr_group))
+ retval = sysfs_create_group(hstate_kobjs[hi],
+ &hstate_demote_attr_group);
+ if (retval) {
pr_warn("HugeTLB unable to create demote interfaces for %s\n", h->name);
+ sysfs_remove_group(hstate_kobjs[hi], hstate_attr_group);
+ kobject_put(hstate_kobjs[hi]);
+ hstate_kobjs[hi] = NULL;
+ return retval;
+ }
}
- return retval;
+ return 0;
}
static void __init hugetlb_sysfs_init(void)
@@ -3941,10 +3947,15 @@ static void hugetlb_unregister_node(struct node *node)
for_each_hstate(h) {
int idx = hstate_index(h);
- if (nhs->hstate_kobjs[idx]) {
- kobject_put(nhs->hstate_kobjs[idx]);
- nhs->hstate_kobjs[idx] = NULL;
- }
+ struct kobject *hstate_kobj = nhs->hstate_kobjs[idx];
+
+ if (!hstate_kobj)
+ continue;
+ if (h->demote_order)
+ sysfs_remove_group(hstate_kobj, &hstate_demote_attr_group);
+ sysfs_remove_group(hstate_kobj, &per_node_hstate_attr_group);
+ kobject_put(hstate_kobj);
+ nhs->hstate_kobjs[idx] = NULL;
}
kobject_put(nhs->hugepages_kobj);
--
2.23.0