In the Linux kernel, the following vulnerability has been resolved: ARM: 9063/1: mm: reduce maximum number of CPUs if DEBUG_KMAP_LOCAL is enabled The debugging code for kmap_local() doubles the num…

Summary

In the Linux kernel, the following vulnerability has been resolved: ARM: 9063/1: mm: reduce maximum number of CPUs if DEBUG_KMAP_LOCAL is enabled The debugging code for kmap_local() doubles the number of per-CPU fixmap slots allocated for kmap_local(), in order to use half of them as guard regions. This causes the fixmap region to grow downwards beyond the start of its reserved window if the supported number of CPUs is large, and collide with the newly added virtual DT mapping right below it,…