1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Clang Control Flow Integrity (CFI) support. 4 * 5 * Copyright (C) 2022 Google LLC 6 */ 7 #ifndef _LINUX_CFI_H 8 #define _LINUX_CFI_H 9 10 #include <linux/bug.h> 11 #include <linux/module.h> 12 #include <asm/cfi.h> 13 14 #ifndef cfi_get_offset 15 static inline int cfi_get_offset(void) 16 { 17 return 0; 18 } 19 #endif 20 21 #ifdef CONFIG_CFI_CLANG 22 enum bug_trap_type report_cfi_failure(struct pt_regs *regs, unsigned long addr, 23 unsigned long *target, u32 type); 24 25 static inline enum bug_trap_type report_cfi_failure_noaddr(struct pt_regs *regs, 26 unsigned long addr) 27 { 28 return report_cfi_failure(regs, addr, NULL, 0); 29 } 30 #endif /* CONFIG_CFI_CLANG */ 31 32 #ifdef CONFIG_ARCH_USES_CFI_TRAPS 33 bool is_cfi_trap(unsigned long addr); 34 #else 35 static inline bool is_cfi_trap(unsigned long addr) { return false; } 36 #endif 37 38 #ifdef CONFIG_MODULES 39 #ifdef CONFIG_ARCH_USES_CFI_TRAPS 40 void module_cfi_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, 41 struct module *mod); 42 #else 43 static inline void module_cfi_finalize(const Elf_Ehdr *hdr, 44 const Elf_Shdr *sechdrs, 45 struct module *mod) {} 46 #endif /* CONFIG_ARCH_USES_CFI_TRAPS */ 47 #endif /* CONFIG_MODULES */ 48 49 #ifndef CFI_NOSEAL 50 #define CFI_NOSEAL(x) 51 #endif 52 53 #endif /* _LINUX_CFI_H */ 54