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author | Andrea Arcangeli <aarcange@redhat.com> | 2018-11-30 14:09:32 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-11-30 14:56:14 -0800 |
commit | 29ec90660d68bbdd69507c1c8b4e33aa299278b1 (patch) | |
tree | 8b23230b8554fe963152a3f8cdff152a5b7f72e4 /mm/shmem.c | |
parent | 5b51072e97d587186c2f5390c8c9c1fb7e179505 (diff) | |
download | linux-29ec90660d68bbdd69507c1c8b4e33aa299278b1.tar.gz linux-29ec90660d68bbdd69507c1c8b4e33aa299278b1.tar.bz2 linux-29ec90660d68bbdd69507c1c8b4e33aa299278b1.zip |
userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas
After the VMA to register the uffd onto is found, check that it has
VM_MAYWRITE set before allowing registration. This way we inherit all
common code checks before allowing to fill file holes in shmem and
hugetlbfs with UFFDIO_COPY.
The userfaultfd memory model is not applicable for readonly files unless
it's a MAP_PRIVATE.
Link: http://lkml.kernel.org/r/20181126173452.26955-4-aarcange@redhat.com
Fixes: ff62a3421044 ("hugetlb: implement memfd sealing")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Hugh Dickins <hughd@google.com>
Reported-by: Jann Horn <jannh@google.com>
Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Cc: <stable@vger.kernel.org>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/shmem.c')
0 files changed, 0 insertions, 0 deletions