Re: [PATCH v5 00/39] Shadow stacks for userspace

[John Allen]

On 1/19/23 3:22 PM, Rick Edgecombe wrote:
> I left tested-by tags in place per discussion with testers. Testers, please
> retest.

Re-tested on my AMD system (Dell PowerEdge R6515 w/ EPYC 7713) and it looks
like everything is still working properly.

The selftests seem to run cleanly:

[INFO]	new_ssp = 7ff19be0dff8, *new_ssp = 7ff19be0e001
[INFO]	changing ssp from 7ff19c7f1ff0 to 7ff19be0dff8
[INFO]	ssp is now 7ff19be0e000
[OK]	Shadow stack pivot
[OK]	Shadow stack faults
[INFO]	Corrupting shadow stack
[INFO]	Generated shadow stack violation successfully
[OK]	Shadow stack violation test
[INFO]	Gup read -> shstk access success
[INFO]	Gup write -> shstk access success
[INFO]	Violation from normal write
[INFO]	Gup read -> write access success
[INFO]	Violation from normal write
[INFO]	Gup write -> write access success
[INFO]	Cow gup write -> write access success
[OK]	Shadow gup test
[INFO]	Violation from shstk access
[OK]	mprotect() test
[OK]	Userfaultfd test
[OK]	32 bit test

Additionally, I could see the control protection messages in dmesg when
running the shstk violation test from here:
https://gitlab.com/cet-software/cet-smoke-test

ld-linux-x86-64[99764] control protection ip:401139 sp:7fff025507d8 ssp:7f186e017fd8 error:1(near ret) in shstk1[401000+1000]

Tested-by: John Allen <john.allen@xxxxxxx>