suprotect
A Proof-Of-Concept Linux kernel module for changing memory protection in an arbitrary process (x64 only).
Instructions
To compile the kernel module and the user-mode utility, run make. To clean the project directory, run make clean.
To load the kernel module, run sudo insmod suprotect.ko. To unload the kernel module, run sudo rmmod suprotect.ko.
To change memory protection, run the uesr-mode utility suprotect-cli with this usage (while the kernel module is loaded, of course):
Usage: ./suprotect-cli <pid> <addr> <len> <prot>
Note: all the parameters are in hex, except the pid.
Example
Let's run python with an infinite loop:
ron@ron-ubuntu:~/suprotect$ python -c "while True: pass" &
[1] 4504
First, check its memory mapping:
ron@ron-ubuntu:~/suprotect$ sudo cat /proc/4504/maps
56143b00d000-56143b315000 r-xp 00000000 08:01 1579941 /usr/bin/python2.7
56143b515000-56143b517000 r--p 00308000 08:01 1579941 /usr/bin/python2.7
56143b517000-56143b58d000 rw-p 0030a000 08:01 1579941 /usr/bin/python2.7
...
Remove the execute access for the entire executable region (prot=1 is read only):
ron@ron-ubuntu:~/suprotect$ sudo ./suprotect-cli 4504 0x56143b00d000 0x308000 1
Immediately, the python process is killed due to segmentation fault:
[1]+ Segmentation fault (core dumped) python -c "while True: pass"