drivers/acpi/debugfs.c in the Linux kernel before 3.0 allows local users to modify arbitrary kernel memory locations by leveraging root privileges to write to the /sys/kernel/debug/acpi/custom_method file. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-4347.
https://github.com/torvalds/linux/commit/526b4af47f44148c9d665e57723ed9f86634c6e3
https://euvd.enisa.europa.eu/vulnerability/EUVD-2011-1038
https://bugzilla.redhat.com/show_bug.cgi?id=680841