linux/arch/x86/kernel/cfi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Clang Control Flow Integrity (CFI) support.
 *
 * Copyright (C) 2022 Google LLC
 */
#include <linux/string.h>
#include <linux/cfi.h>
#include <asm/insn.h>
#include <asm/insn-eval.h>

/*
 * Returns the target address and the expected type when regs->ip points
 * to a compiler-generated CFI trap.
 */
static bool decode_cfi_insn(struct pt_regs *regs, unsigned long *target,
			    u32 *type)
{ … }

/*
 * Checks if a ud2 trap is because of a CFI failure, and handles the trap
 * if needed. Returns a bug_trap_type value similarly to report_bug.
 */
enum bug_trap_type handle_cfi_failure(struct pt_regs *regs)
{ … }

/*
 * Ensure that __kcfi_typeid_ symbols are emitted for functions that may
 * not be indirectly called with all configurations.
 */
__ADDRESSABLE(__memcpy)