summaryrefslogtreecommitdiff
path: root/mm/userfaultfd.c
diff options
context:
space:
mode:
authorDavid Hildenbrand <david@redhat.com>2022-12-23 18:56:16 +0300
committerAndrew Morton <akpm@linux-foundation.org>2023-01-19 04:12:50 +0300
commit1ef488edd6c4d447784710974f049628c2890481 (patch)
treea3577746e57294945403990ca3dd33a9a0986ee4 /mm/userfaultfd.c
parent931298e103c228c4ce6d13e7b5781aeaaff37ac7 (diff)
downloadlinux-1ef488edd6c4d447784710974f049628c2890481.tar.xz
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.c3
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);
}