CVE-2022-49744 mm/uffd: fix pte marker when fork() without fork event

In the Linux kernel, the following vulnerability has been resolved: mm/uffd: fix pte marker when fork without fork event Patch series "mm: Fixes on pte markers". Patch 1 resolves the syzkiller report from Pengfei. Patch 2 further harden pte markers when used with the recent swapin error markers...