Base: Add UMIP to Mitigations(7)

This commit is contained in:
Idan Horowitz 2022-03-22 20:14:47 +02:00
parent f0166efe8c
commit b880b64446
Notes: sideshowbarker 2024-07-17 16:51:50 +09:00

View File

@ -41,6 +41,22 @@ Date: Sun Jan 5 18:00:15 2020 +0100
Kernel: Start implementing x86 SMAP support
```
### UMIP (User Mode Instruction Prevention)
User Mode Instruction Prevention is an x86 CPU security feature which prevents execution of specific privileged
instructions in user mode (SGDT, SIDT, SLDT, SMSW, STR).
These instructions let user mode code query the addresses of various kernel structures (the GDT, LDT, IDT, etc),
meaning that they leak kernel addresses that can be exploited to defeat ASLR.
It was enabled in the following [commit](https://github.com/SerenityOS/serenity/commit/9c0836ce97ae36165abd8eb5241bb5239af3a756):
```
commit 9c0836ce97ae36165abd8eb5241bb5239af3a756
Author: Andreas Kling <awesomekling@gmail.com>
Date: Wed Jan 1 13:02:32 2020 +0100
Kernel: Enable x86 UMIP (User Mode Instruction Prevention) if supported
```
### Pledge
[pledge](https://marc.info/?l=openbsd-tech&m=143725996614627&w=2) is a mitigation which originated from OpenBSD.