Re: [PATCH 2/2] mm/hugetlb: Fix cow where page writtable in child

[Mike Kravetz]

On 5/1/21 7:41 AM, Peter Xu wrote:
> When fork() and copy hugetlb page range, we'll remember to wrprotect src pte if
> needed, however we forget about the child!  Without it, the child will be able
> to write to parent's pages when mapped as PROT_READ|PROT_WRITE and MAP_PRIVATE,
> which will cause data corruption in the parent process.
> 
> This issue can also be exposed by "memfd_test hugetlbfs" kselftest (if it can
> pass the F_SEAL_FUTURE_WRITE test first, though).
> 
> Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
> ---
>  mm/hugetlb.c | 2 ++
>  1 file changed, 2 insertions(+)

Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>

I think we need to add, "Fixes: 4eae4efa2c29" as this is now in v5.12
-- 
Mike Kravetz