arm64: add ptrace regsets for ptrauth key management

Add two new ptrace regsets, which can be used to request and change the
pointer authentication keys of a thread. NT_ARM_PACA_KEYS gives access
to the instruction/data address keys, and NT_ARM_PACG_KEYS to the
generic authentication key. The keys are also part of the core dump file
of the process.

The regsets are only exposed if the kernel is compiled with
CONFIG_CHECKPOINT_RESTORE=y, as the only intended use case is
checkpointing and restoring processes that are using pointer
authentication. (This can be changed later if there are other use
cases.)

Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h
index 28d77c9ed531..d78623acb649 100644
--- a/arch/arm64/include/uapi/asm/ptrace.h
+++ b/arch/arm64/include/uapi/asm/ptrace.h
@@ -233,6 +233,19 @@ struct user_pac_mask {
 	__u64		insn_mask;
 };
 
+/* pointer authentication keys (NT_ARM_PACA_KEYS, NT_ARM_PACG_KEYS) */
+
+struct user_pac_address_keys {
+	__uint128_t	apiakey;
+	__uint128_t	apibkey;
+	__uint128_t	apdakey;
+	__uint128_t	apdbkey;
+};
+
+struct user_pac_generic_keys {
+	__uint128_t	apgakey;
+};
+
 #endif /* __ASSEMBLY__ */
 
 #endif /* _UAPI__ASM_PTRACE_H */