Commit 2d032410 authored Feb 24, 2021 by Miaohe Lin Committed by Greg Kroah-Hartman Mar 04, 2021

mm/hugetlb: fix potential double free in hugetlb_register_node() error path

[ Upstream commit cc2205a67dec5a700227a693fc113441e73e4641 ]

In hugetlb_sysfs_add_hstate(), we would do kobject_put() on hstate_kobjs
when failed to create sysfs group but forget to set hstate_kobjs to NULL.
Then in hugetlb_register_node() error path, we may free it again via
hugetlb_unregister_node().

Link: https://lkml.kernel.org/r/20210107123249.36964-1-linmiaohe@huawei.com


Fixes: a3437870 ("hugetlb: new sysfs interface")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <smuchun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 39e913ee

mm/hugetlb.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -2648,8 +2648,10 @@ static int hugetlb_sysfs_add_hstate(struct hstate h, struct kobject parent,
		return -ENOMEM;

		retval = sysfs_create_group(hstate_kobjs[hi], hstate_attr_group);
		if (retval)
		if (retval) {
		kobject_put(hstate_kobjs[hi]);
		hstate_kobjs[hi] = NULL;
		}

		return retval;
		}