linux/kernel/cfi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Clang Control Flow Integrity (CFI) error handling.
 *
 * Copyright (C) 2022 Google LLC
 */

#include <linux/cfi.h>

enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr,
				      unsigned long *target, u32 type)
{ … }

#ifdef CONFIG_ARCH_USES_CFI_TRAPS
static inline unsigned long trap_address(s32 *p)
{ … }

static bool is_trap(unsigned long addr, s32 *start, s32 *end)
{ … }

#ifdef CONFIG_MODULES
/* Populates `kcfi_trap(_end)?` fields in `struct module`. */
void module_cfi_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs,
			 struct module *mod)
{ … }

static bool is_module_cfi_trap(unsigned long addr)
{ … }
#else /* CONFIG_MODULES */
static inline bool is_module_cfi_trap(unsigned long addr)
{
	return false;
}
#endif /* CONFIG_MODULES */

extern s32 __start___kcfi_traps[];
extern s32 __stop___kcfi_traps[];

bool is_cfi_trap(unsigned long addr)
{ … }
#endif /* CONFIG_ARCH_USES_CFI_TRAPS */