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Diffstat (limited to 'mm')
-rw-r--r--mm/userfaultfd.c58
1 files changed, 28 insertions, 30 deletions
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 1e5c2f94e8a3..9f0ad2a4f102 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -197,22 +197,25 @@ retry:
* retry, dst_vma will be set to NULL and we must lookup again.
*/
if (!dst_vma) {
- err = -EINVAL;
+ err = -ENOENT;
dst_vma = find_vma(dst_mm, dst_start);
if (!dst_vma || !is_vm_hugetlb_page(dst_vma))
goto out_unlock;
-
- if (vma_hpagesize != vma_kernel_pagesize(dst_vma))
- goto out_unlock;
-
/*
- * Make sure the remaining dst range is both valid and
- * fully within a single existing vma.
+ * Only allow __mcopy_atomic_hugetlb on userfaultfd
+ * registered ranges.
*/
+ if (!dst_vma->vm_userfaultfd_ctx.ctx)
+ goto out_unlock;
+
if (dst_start < dst_vma->vm_start ||
dst_start + len > dst_vma->vm_end)
goto out_unlock;
+ err = -EINVAL;
+ if (vma_hpagesize != vma_kernel_pagesize(dst_vma))
+ goto out_unlock;
+
vm_shared = dst_vma->vm_flags & VM_SHARED;
}
@@ -221,12 +224,6 @@ retry:
goto out_unlock;
/*
- * Only allow __mcopy_atomic_hugetlb on userfaultfd registered ranges.
- */
- if (!dst_vma->vm_userfaultfd_ctx.ctx)
- goto out_unlock;
-
- /*
* If not shared, ensure the dst_vma has a anon_vma.
*/
err = -ENOMEM;
@@ -404,22 +401,35 @@ retry:
* Make sure the vma is not shared, that the dst range is
* both valid and fully within a single existing vma.
*/
- err = -EINVAL;
+ err = -ENOENT;
dst_vma = find_vma(dst_mm, dst_start);
if (!dst_vma)
goto out_unlock;
/*
- * shmem_zero_setup is invoked in mmap for MAP_ANONYMOUS|MAP_SHARED but
- * it will overwrite vm_ops, so vma_is_anonymous must return false.
+ * 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.
*/
- if (WARN_ON_ONCE(vma_is_anonymous(dst_vma) &&
- dst_vma->vm_flags & VM_SHARED))
+ if (!dst_vma->vm_userfaultfd_ctx.ctx)
goto out_unlock;
if (dst_start < dst_vma->vm_start ||
dst_start + len > dst_vma->vm_end)
goto out_unlock;
+ err = -EINVAL;
+ /*
+ * shmem_zero_setup is invoked in mmap for MAP_ANONYMOUS|MAP_SHARED but
+ * it will overwrite vm_ops, so vma_is_anonymous must return false.
+ */
+ if (WARN_ON_ONCE(vma_is_anonymous(dst_vma) &&
+ dst_vma->vm_flags & VM_SHARED))
+ goto out_unlock;
+
/*
* If this is a HUGETLB vma, pass off to appropriate routine
*/
@@ -427,18 +437,6 @@ retry:
return __mcopy_atomic_hugetlb(dst_mm, dst_vma, dst_start,
src_start, len, zeropage);
- /*
- * 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.
- */
- if (!dst_vma->vm_userfaultfd_ctx.ctx)
- goto out_unlock;
-
if (!vma_is_anonymous(dst_vma) && !vma_is_shmem(dst_vma))
goto out_unlock;