CVE-2023-52940

In the Linux kernel, the following vulnerability has been resolved:

mm: multi-gen LRU: fix crash during cgroup migration

lrugenmigratemm() assumes lrugenaddmm() runs prior to itself. This isn't true for the following scenario:

CPU 1                         CPU 2

clone() cgroupcanfork() cgroupprocswrite() cgrouppostfork() tasklock() lrugenmigratemm() taskunlock() tasklock() lrugenaddmm() taskunlock()

And when the above happens, kernel crashes because of linked list corruption (mmstruct->lrugen.list).