[PATCH v2 Zisslpcfi 0/2] Support for zisslpcfi in opensbi

[Deepak Gupta]

Please don't bother with your time and ignore this patch series.
Something went wrong on my setup and patches didn't come out as expected.

I'll send a new version.
Apologies.

-Deepak

On Wed, Dec 21, 2022 at 11:55 AM Deepak Gupta <debug at rivosinc.com> wrote:
>
> Zisslpcfi [1] extension extends risc-v architecture to mitigate against
> control-flow integrity attacks (ROP/JOP/COP).
>
> Zisslpcfi uses bits (b23-b29) in (m/s/vs) status CSR for enabling cfi in
> lesser privileged mode and record cfi state. One such state is expected
> landing pad (ELP). If forward cfi is enabled, indirect call/jmp updates
> hart's ELP state (1bit) to true. ELP state is cleared only by a landing
> pad instruction else trap is delivered with ELP state recorded in sstatus
> CSR.
>
> This two patch series adds following changes to opensbi
>     - Adds support in opensbi to detect zisslpcfi
>     - trap redirection updates ELP state accordingly
>
> Qemu implementation for Zisslpcfi can be checked out on github [2]
> Strawman linux kernel enabling (still very early) can be checked out on github [3]
>
> [1] - https://github.com/riscv/riscv-cfi
> [2] - https://github.com/deepak0414/qemu/tree/gh_Zisslpcfi-0.1
> [3] - https://github.com/deepak0414/linux-riscv-cfi/tree/Zisslpcfi-0.1_v6.1-rc2
>
> Deepak Gupta (2):
>   include: adding support for Zisslpcfi encodings
>   lib: sbi: Zisslpcfi detection and elp cfi state reflect back in status
>
>  include/sbi/riscv_encoding.h |  6 ++++++
>  include/sbi/sbi_hart.h       |  2 ++
>  lib/sbi/sbi_hart.c           | 21 +++++++++++++++++++++
>  lib/sbi/sbi_trap.c           | 18 ++++++++++++++++++
>  4 files changed, 47 insertions(+)
>
> --
> 2.25.1
>