mm/rmap: fix comment in anon_vma_clone()

Commit 2555283eb4 ("mm/rmap: Fix anon_vma->degree ambiguity leading to
double-reuse") use num_children and num_active_vmas to replace the origin
degree to fix anon_vma UAF problem.  Update the comment in anon_vma_clone
to fit this change.

Link: https://lkml.kernel.org/r/20221014013931.1565969-1-mawupeng1@huawei.com
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Ma Wupeng 2022-10-14 09:39:31 +08:00 committed by Andrew Morton
parent e51da3a9b6
commit d8e454eb44

View File

@ -315,8 +315,8 @@ int anon_vma_clone(struct vm_area_struct *dst, struct vm_area_struct *src)
enomem_failure:
/*
* dst->anon_vma is dropped here otherwise its degree can be incorrectly
* decremented in unlink_anon_vmas().
* dst->anon_vma is dropped here otherwise its num_active_vmas can
* be incorrectly decremented in unlink_anon_vmas().
* We can safely do this because callers of anon_vma_clone() don't care
* about dst->anon_vma if anon_vma_clone() failed.
*/