From: Naoya Horiguchi naoya.horiguchi@nec.com
mainline inclusion from mainline-v5.13-rc5 commit 0c5da35723a961d8c02ea516da2bcfeb007d7d2c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I9SZXR CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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When memory_failure() or soft_offline_page() is called on a tail page of some hugetlb page, "BUG: unable to handle page fault" error can be triggered.
remove_hugetlb_page() dereferences page->lru, so it's assumed that the page points to a head page, but one of the caller, dissolve_free_huge_page(), provides remove_hugetlb_page() with 'page' which could be a tail page. So pass 'head' to it, instead.
Link: https://lkml.kernel.org/r/20210526235257.2769473-1-nao.horiguchi@gmail.com Fixes: 6eb4e88a6d27 ("hugetlb: create remove_hugetlb_page() to separate functionality") Signed-off-by: Naoya Horiguchi naoya.horiguchi@nec.com Reviewed-by: Mike Kravetz mike.kravetz@oracle.com Reviewed-by: Muchun Song songmuchun@bytedance.com Acked-by: Michal Hocko mhocko@suse.com Reviewed-by: Oscar Salvador osalvador@suse.de Cc: Miaohe Lin linmiaohe@huawei.com Cc: Matthew Wilcox willy@infradead.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org
Conflicts: mm/hugetlb.c [Context conflicts.] Signed-off-by: Jinjiang Tu tujinjiang@huawei.com --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 2844458b5fc5..10509d9f9c58 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1852,7 +1852,7 @@ int dissolve_free_huge_page(struct page *page) SetPageHWPoison(page); ClearPageHWPoison(head); } - remove_hugetlb_page(h, page, false); + remove_hugetlb_page(h, head, false); h->max_huge_pages--; spin_unlock_irq(&hugetlb_lock); update_and_free_page(h, head);