diff options
Diffstat (limited to 'mm/userfaultfd.c')
| -rw-r--r-- | mm/userfaultfd.c | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 471b6457f95f..43cf314cfddd 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -205,8 +205,9 @@ retry: if (!dst_vma || !is_vm_hugetlb_page(dst_vma)) goto out_unlock; /* - * Only allow __mcopy_atomic_hugetlb on userfaultfd - * registered ranges. + * Check the vma is registered in uffd, this is + * required to enforce the VM_MAYWRITE check done at + * uffd registration time. */ if (!dst_vma->vm_userfaultfd_ctx.ctx) goto out_unlock; @@ -459,13 +460,9 @@ retry: if (!dst_vma) goto out_unlock; /* - * Be strict and only allow __mcopy_atomic on userfaultfd - * registered ranges to prevent userland errors going - * unnoticed. As far as the VM consistency is concerned, it - * would be perfectly safe to remove this check, but there's - * no useful usage for __mcopy_atomic ouside of userfaultfd - * registered ranges. This is after all why these are ioctls - * belonging to the userfaultfd and not syscalls. + * Check the vma is registered in uffd, this is required to + * enforce the VM_MAYWRITE check done at uffd registration + * time. */ if (!dst_vma->vm_userfaultfd_ctx.ctx) goto out_unlock; |