Description: cgroup: Use open-time creds and namespace for migration perm checks
References:
 https://lore.kernel.org/lkml/20211209214707.805617-1-tj@kernel.org/T/
 https://bugzilla.redhat.com/show_bug.cgi?id=2035652
Notes:
 carnil> Fixed as well in 5.15.14 for 5.15.y.
Bugs:
upstream: released (5.16) [1756d7994ad85c2479af6ae5a9750b92324685af, 0d2b5955b36250a9428c832664f2079cbf723bec, e57457641613fef0d147ede8bd6a3047df588b95]
5.10-upstream-stable:
4.19-upstream-stable:
4.9-upstream-stable:
sid: released (5.15.15-1)
5.10-bullseye-security:
4.19-buster-security:
4.9-stretch-security: