From: Miaohe Lin <linmiaohe@xxxxxxxxxx> 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@xxxxxxxxxx Fixes: f619147104c8 ("userfaultfd: add UFFDIO_CONTINUE ioctl") Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Axel Rasmussen <axelrasmussen@xxxxxxxxxx> Cc: Peter Xu <peterx@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -6026,7 +6026,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_s if (!huge_pte_none_mostly(huge_ptep_get(dst_pte))) goto out_release_unlock; - if (vm_shared) { + if (page_in_pagecache) { page_dup_file_rmap(page, true); } else { ClearHPageRestoreReserve(page);
