From: Deepak Gupta Date: Wed, 8 Feb 2023 20:26:52 -0800 Subject: [PATCH v3 Zisslpcfi 0/2] Support for zisslpcfi in opensbi Message-ID: <20230209042654.3568990-1-debug@rivosinc.com> List-Id: To: opensbi@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit zisslpcfi [1] extension extends risc-v architecture to mitigate against control-flow integrity attacks (ROP/JOP/COP). zisslpcfi uses bits (b23-b26) in (m/s/vs) status CSR for enabling cfi in U 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 | 10 ++++++++++ include/sbi/sbi_hart.h | 2 ++ lib/sbi/sbi_hart.c | 23 +++++++++++++++++++++++ lib/sbi/sbi_trap.c | 16 ++++++++++++++++ 4 files changed, 51 insertions(+) -- 2.25.1