[CS] Memory Protection

 

1. Memory Protection Overview

In Memory protection, computers protect the operating system from user processes using a limit register and a relocation register.

1) relocation register: physical address

2) limit register: logical address

3) MMU (Memory Management unit): translate the logical address to physical address dynamically.

 

2. Need of Memory Protection

1) preventing from accessing unallocated memory

  -> stops the software from seizing control of an excessive amount of memory

  -> cause damage that will impact other software which is currently being used

  -> creates a loss of saved data

2) detecting malicious or harmful applications

 

3. Methods of Memory Protection

Different operating systems use different forms of memory protection

 

1) Memory protection using Keys

2) Memory protection using Rigs

3) Capability-based addressing

4) Memory Protection using masks

5) Memory Protection using Segmentation

6) Memory Protection using Simulated segmentation

7) Memory Protection using Dynamic tainting

 

Source:

https://geeksforgeeks.org/memory-protection-in-operating-systems/