security-misc/etc/sysctl.d/30_security-misc_kexec-disable.conf

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## See the file COPYING for copying conditions.

## Quote https://www.kernel.org/doc/html/latest/admin-guide/sysctl/kernel.html
##
## kexec_load_disabled:
##
## A toggle indicating if the kexec_load syscall has been disabled. This value defaults to 0 (false: kexec_load enabled), but can be set to 1 (true: kexec_load disabled). Once true, kexec can no longer be used, and the toggle cannot be set back to false. This allows a kexec image to be loaded before disabling the syscall, allowing a system to set up (and later use) an image without it being altered. Generally used together with the "modules_disabled" sysctl.
## Disables kexec which can be used to replace the running kernel.
kernel.kexec_load_disabled=1

## Why is this in a dedicated config file?
## Package ram-wipe requires kexec. However, ram-wipe could not ship a config
## file /etc/sysctl.d/40_ram-wipe.conf which sets 'kernel.kexec_load_disabled=0'.
## This is because once systemd-sysctl.service has set 'kernel.kexec_load_disabled=1'
## it cannot be undone without reboot. This is a upstream Linux security feature.