On Mon, Aug 29, 2022 at 12:38 AM <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > The patch below does not apply to the 5.15-stable tree. > If someone wants it applied there, or to any other stable or longterm > tree, then please email the backport, including the original git commit > id to <stable@xxxxxxxxxxxxxxx>. I'm in favor of applying this to 5.15. I can send a backport, unless someone else was already planning to do it (don't want to duplicate effort)? > > thanks, > > greg k-h > > ------------------ original commit in Linus's tree ------------------ > > From ab74ef708dc51df7cf2b8a890b9c6990fac5c0c6 Mon Sep 17 00:00:00 2001 > From: Miaohe Lin <linmiaohe@xxxxxxxxxx> > Date: Tue, 12 Jul 2022 21:05:42 +0800 > Subject: [PATCH] mm/hugetlb: avoid corrupting page->mapping in > hugetlb_mcopy_atomic_pte > > 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> > > diff --git a/mm/hugetlb.c b/mm/hugetlb.c > index 2480ba627aa5..e070b8593b37 100644 > --- a/mm/hugetlb.c > +++ b/mm/hugetlb.c > @@ -6041,7 +6041,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm, > 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); >
