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From:   Peter Xu <peterx@redhat.com>
To:     linux-mm@kvack.org, linux-kernel@vger.kernel.org
Cc:     Axel Rasmussen <axelrasmussen@google.com>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>, peterx@redhat.com,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Hugh Dickins <hughd@google.com>
Subject: [PATCH v2 0/2] mm/hugetlb: Fix issues on file sealing and fork
Date:   Mon,  3 May 2021 19:43:54 -0400
Message-Id: <20210503234356.9097-1-peterx@redhat.com>
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v2:=0D
- Move seal check to be after setting VM_HUGETLB [Mike]=0D
- Rewrite commit message for patch 2, explaining more on why it got broken=
=0D
- Add r-bs for Mike=0D
=0D
Hugh reported issue with F_SEAL_FUTURE_WRITE not applied correctly to=0D
hugetlbfs, which I can easily verify using the memfd_test program, which se=
ems=0D
that the program is hardly run with hugetlbfs pages (as by default shmem).=
=0D
=0D
Meanwhile I found another probably even more severe issue on that hugetlb f=
ork=0D
won't wr-protect child cow pages, so child can potentially write to parent=
=0D
private pages.  Patch 2 addresses that.=0D
=0D
After this series applied, "memfd_test hugetlbfs" should start to pass.=0D
=0D
Please review, thanks.=0D
=0D
Peter Xu (2):=0D
  mm/hugetlb: Fix F_SEAL_FUTURE_WRITE=0D
  mm/hugetlb: Fix cow where page writtable in child=0D
=0D
 fs/hugetlbfs/inode.c |  5 +++++=0D
 include/linux/mm.h   | 32 ++++++++++++++++++++++++++++++++=0D
 mm/hugetlb.c         |  1 +=0D
 mm/shmem.c           | 22 ++++------------------=0D
 4 files changed, 42 insertions(+), 18 deletions(-)=0D
=0D
-- =0D
2.31.1=0D
=0D