[PATCH v2 0/4] modsign enhancement

[Jia Zhang]

This patch series allows to disable module validity enforcement
in runtime through /sys/kernel/security/modsign/enforce interface.

Assuming CONFIG_MODULE_SIG_FORCE=y, here are the instructions to
disable the validity enforcement.

# cat /sys/kernel/security/modsign/enforce
# echo -n 0 > data
# openssl smime -sign -nocerts -noattr -binary -in data \
    -inkey <system_trusted_key> -signer <cert> -outform der \
    -out /sys/kernel/security/modsign/enforce

Now enable enforcement again on demand.

# echo 1 > /sys/kernel/security/modsign/enforce

Changelog:
v2:
- Support to disable validity enforcement in runtime.