CVE-2022-50849 pstore: Avoid kcore oops by vmap()ing with VM_IOREMAP

In the Linux kernel, the following vulnerability has been resolved: pstore: Avoid kcore oops by vmaping with VMIOREMAP An oops can be induced by running 'cat /proc/kcore /dev/null' on devices using pstore with the ram backend because kmapatomic assumes lowmem pages are accessible with va. Unable ...