This is a note to let you know that I've just added the patch titled mm/hugetlb: fix potential double free in hugetlb_register_node() error path to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mm-hugetlb-fix-potential-double-free-in-hugetlb_regi.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit adf6799a4fc2926f908ba8bc5c665a9e247524aa Author: Miaohe Lin <linmiaohe@xxxxxxxxxx> Date: Wed Feb 24 12:06:50 2021 -0800 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@xxxxxxxxxx Fixes: a3437870160c ("hugetlb: new sysfs interface") Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Reviewed-by: Muchun Song <smuchun@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/mm/hugetlb.c b/mm/hugetlb.c index d5b03b9262d4f..2e2527c9f9a21 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2812,8 +2812,10 @@ 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; }