memcg: fix possible use-after-free in memcg_write_event_control()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v4.19.269 by commit e1ae97624ecf400ea56c238bff23e5cd139df0b8, it was introduced in version v3.14 by commit 347c4a8747104a945ecced358944e42879176ca5. For more details please see the references link.