gcc/libsanitizer/sanitizer_common/sanitizer_ptrauth.h

44 lines
1.7 KiB
C++

//===-- sanitizer_ptrauth.h -------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef SANITIZER_PTRAUTH_H
#define SANITIZER_PTRAUTH_H
#if __has_feature(ptrauth_intrinsics)
# include <ptrauth.h>
#elif defined(__ARM_FEATURE_PAC_DEFAULT) && !defined(__APPLE__)
// On the stack the link register is protected with Pointer
// Authentication Code when compiled with -mbranch-protection.
// Let's stripping the PAC unconditionally because xpaclri is in
// the NOP space so will do nothing when it is not enabled or not available.
# define ptrauth_strip(__value, __key) \
({ \
__typeof(__value) ret; \
asm volatile( \
"mov x30, %1\n\t" \
"hint #7\n\t" \
"mov %0, x30\n\t" \
"mov x30, xzr\n\t" \
: "=r"(ret) \
: "r"(__value) \
: "x30"); \
ret; \
})
# define ptrauth_auth_data(__value, __old_key, __old_data) __value
# define ptrauth_string_discriminator(__string) ((int)0)
#else
// Copied from <ptrauth.h>
# define ptrauth_strip(__value, __key) __value
# define ptrauth_auth_data(__value, __old_key, __old_data) __value
# define ptrauth_string_discriminator(__string) ((int)0)
#endif
#define STRIP_PAC_PC(pc) ((uptr)ptrauth_strip(pc, 0))
#endif // SANITIZER_PTRAUTH_H