diff mbox series

[RFC,v1,22/28] riscv sigcontext: adding cfi state field in sigcontext

Message ID 20240125062739.1339782-23-debug@rivosinc.com
State New
Headers
Series riscv control-flow integrity for usermode |

Commit Message

Deepak Gupta Jan. 25, 2024, 6:21 a.m. UTC 
  From: Deepak Gupta <debug@rivosinc.com>

Shadow stack needs to be saved and restored on signal delivery and signal
return.

sigcontext embedded in ucontext is extendible. Adding cfi state in there
which can be used to save cfi state before signal delivery and restore
cfi state on sigreturn

Signed-off-by: Deepak Gupta <debug@rivosinc.com>
---
 arch/riscv/include/uapi/asm/sigcontext.h | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/arch/riscv/include/uapi/asm/sigcontext.h b/arch/riscv/include/uapi/asm/sigcontext.h
index cd4f175dc837..5ccdd94a0855 100644
--- a/arch/riscv/include/uapi/asm/sigcontext.h
+++ b/arch/riscv/include/uapi/asm/sigcontext.h
@@ -21,6 +21,10 @@  struct __sc_riscv_v_state {
 	struct __riscv_v_ext_state v_state;
 } __attribute__((aligned(16)));
 
+struct __sc_riscv_cfi_state {
+	unsigned long ss_ptr;	/* shadow stack pointer */
+	unsigned long rsvd;		/* keeping another word reserved in case we need it */
+};
 /*
  * Signal context structure
  *
@@ -29,6 +33,7 @@  struct __sc_riscv_v_state {
  */
 struct sigcontext {
 	struct user_regs_struct sc_regs;
+	struct __sc_riscv_cfi_state sc_cfi_state;
 	union {
 		union __riscv_fp_state sc_fpregs;
 		struct __riscv_extra_ext_header sc_extdesc;