| From | Greg Kroah-Hartman <> | Subject | [PATCH 5.15 09/73] mm/hugetlb: avoid corrupting page->mapping in hugetlb_mcopy_atomic_pte | Date | Fri, 2 Sep 2022 14:18:33 +0200 |
| |
From: Miaohe Lin <linmiaohe@huawei.com>
commit ab74ef708dc51df7cf2b8a890b9c6990fac5c0c6 upstream.
In MCOPY_ATOMIC_CONTINUE case with a non-shared VMA, pages in the page cache are installed in the ptes. But hugepage_add_new_anon_rmap is called for them mistakenly because they're not vm_shared. This will corrupt the page->mapping used by page cache code.
Link: https://lkml.kernel.org/r/20220712130542.18836-1-linmiaohe@huawei.com Fixes: f619147104c8 ("userfaultfd: add UFFDIO_CONTINUE ioctl") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Peter Xu <peterx@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Axel Rasmussen <axelrasmussen@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -5371,7 +5371,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_s if (!huge_pte_none(huge_ptep_get(dst_pte))) goto out_release_unlock; - if (vm_shared) { + if (page_in_pagecache) { page_dup_rmap(page, true); } else { ClearHPageRestoreReserve(page);
|