Description of problem:
I followed a guide for signing kernel modules

https://docs.fedoraproject.org/en-US/Fedora/23/html/System_Administrators_Guide/sect-signing-kernel-module-with-the-private-key.html

and the sign-file script fails with an error.
 

Version-Release number of selected component (if applicable):
kernel-devel-4.7.4-100.fc23.x86_64

How reproducible:
Always.

Steps to Reproduce:
1. You need a key pair
https://docs.fedoraproject.org/en-US/Fedora/23/html/System_Administrators_Guide/sect-generating-a-public-private-x509-key-pair.html

and an unsigned module- I have used the VirtualBox module from rpmfusion 
http://rpmfusion.org/Howto/VirtualBox

2. # perl /usr/src/kernels/4.7.4-100.fc23.x86_64/scripts/sign-file sha256 private_key.priv public_key.der /usr/lib/modules/4.7.4-100.fc23.x86_64/extra/VirtualBox/vboxdrv.ko

Actual results:
Unrecognized character \x7F; marked by <-- HERE after <-- HERE near column 1 at /usr/src/kernels/4.7.4-100.fc23.x86_64/scripts/sign-file line 1.

Expected results:
The module gets signed.

Additional info:
I have reported a bug on the documentation https://bugzilla.redhat.com/show_bug.cgi?id=1379758.