diff options
| author | David Hildenbrand <david@redhat.com> | 2022-12-23 16:56:16 +0100 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-01-18 17:12:50 -0800 |
| commit | 1ef488edd6c4d447784710974f049628c2890481 (patch) | |
| tree | a3577746e57294945403990ca3dd33a9a0986ee4 /mm/userfaultfd.c | |
| parent | 931298e103c228c4ce6d13e7b5781aeaaff37ac7 (diff) | |
mm/mprotect: drop pgprot_t parameter from change_protection()
Being able to provide a custom protection opens the door for
inconsistencies and BUGs: for example, accidentally allowing for more
permissions than desired by other mechanisms (e.g., softdirty tracking).
vma->vm_page_prot should be the single source of truth.
Only PROT_NUMA is special: there is no way we can erroneously allow
for more permissions when removing all permissions. Special-case using
the MM_CP_PROT_NUMA flag.
[david@redhat.com: PAGE_NONE might not be defined without CONFIG_NUMA_BALANCING]
Link: https://lkml.kernel.org/r/5084ff1c-ebb3-f918-6a60-bacabf550a88@redhat.com
Link: https://lkml.kernel.org/r/20221223155616.297723-3-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/userfaultfd.c')
| -rw-r--r-- | mm/userfaultfd.c | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 46771362550f..65ad172add27 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -730,8 +730,7 @@ void uffd_wp_range(struct mm_struct *dst_mm, struct vm_area_struct *dst_vma, if (!enable_wp && vma_wants_manual_pte_write_upgrade(dst_vma)) mm_cp_flags |= MM_CP_TRY_CHANGE_WRITABLE; tlb_gather_mmu(&tlb, dst_mm); - change_protection(&tlb, dst_vma, start, start + len, vma->vm_page_prot, - mm_cp_flags); + change_protection(&tlb, dst_vma, start, start + len, mm_cp_flags); tlb_finish_mmu(&tlb); } |