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

Deepak Gupta debug at rivosinc.com
Sun Dec 11 21:33:38 PST 2022


I forgot to include URLs to qemu and linux implementation of Zisslpcfi

This is where I am maintaining qemu implementation
https://github.com/deepak0414/qemu/tree/gh_Zisslpcfi-0.1

And kernel implementation here
https://github.com/deepak0414/linux-riscv-cfi/tree/Zisslpcfi-0.1_v6.1-rc2

On Sun, Dec 11, 2022 at 07:08:02PM -0800, Deepak Gupta 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
>
>[1] - https://github.com/riscv/riscv-cfi
>
>Deepak Gupta (2):
>  include: adding support for zsslpcfi encodings
>  lib: sbi: zsslpcfi 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
>



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