Ram Pai <linux...@us.ibm.com> writes:
> Pkey tracking information is not copied over to the mm_struct of the
> child during fork(). This can cause the child to erroneously allocate
> keys that were already allocated. Any allocated execute-only key is lost
> aswell.
>
> Add code; called by dup_mmap(), to copy the pkey state from parent to
> child explicitly.
>
> This problem was originally found by Dave Hansen on x86, which turns out
> to be a problem on powerpc aswell.
>
> Reviewed-by: Thiago Jung Bauermann <bauer...@linux.ibm.com>
> Signed-off-by: Ram Pai <linux...@us.ibm.com>
>
> v2: do not copy if pkeys is disabled.
> -- comment by Michael Ellermen
Thanks.
I changed the subject to:
powerpc/pkeys: Fix handling of pkey state across fork()
And added tags:
Fixes: cf43d3b26452 ("powerpc: Enable pkey subsystem")
Cc: sta...@vger.kernel.org # v4.16+
cheers
