1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_POWERPC_KUP_H_ 3 #define _ASM_POWERPC_KUP_H_ 4 5 #define KUAP_READ 1 6 #define KUAP_WRITE 2 7 #define KUAP_READ_WRITE (KUAP_READ | KUAP_WRITE) 8 9 #ifdef CONFIG_PPC_BOOK3S_64 10 #include <asm/book3s/64/kup.h> 11 #endif 12 13 #ifdef CONFIG_PPC_8xx 14 #include <asm/nohash/32/kup-8xx.h> 15 #endif 16 17 #ifdef CONFIG_PPC_BOOK3S_32 18 #include <asm/book3s/32/kup.h> 19 #endif 20 21 #ifdef __ASSEMBLY__ 22 #ifndef CONFIG_PPC_KUAP 23 .macro kuap_check_amr gpr1, gpr2 24 .endm 25 26 #endif 27 28 #else /* !__ASSEMBLY__ */ 29 30 extern bool disable_kuep; 31 extern bool disable_kuap; 32 33 #include <linux/pgtable.h> 34 35 #ifdef CONFIG_PPC_KUEP 36 void setup_kuep(bool disabled); 37 #else 38 static inline void setup_kuep(bool disabled) { } 39 #endif /* CONFIG_PPC_KUEP */ 40 41 #ifndef CONFIG_PPC_BOOK3S_32 42 static inline void kuep_lock(void) { } 43 static inline void kuep_unlock(void) { } 44 #endif 45 46 #ifdef CONFIG_PPC_KUAP 47 void setup_kuap(bool disabled); 48 #else 49 static inline void setup_kuap(bool disabled) { } 50 51 static inline bool 52 bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) 53 { 54 return false; 55 } 56 57 static inline void kuap_assert_locked(void) { } 58 static inline void kuap_save_and_lock(struct pt_regs *regs) { } 59 static inline void kuap_user_restore(struct pt_regs *regs) { } 60 static inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { } 61 62 static inline unsigned long kuap_get_and_assert_locked(void) 63 { 64 return 0; 65 } 66 67 /* 68 * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush 69 * the L1D cache after user accesses. Only include the empty stubs for other 70 * platforms. 71 */ 72 #ifndef CONFIG_PPC_BOOK3S_64 73 static inline void allow_user_access(void __user *to, const void __user *from, 74 unsigned long size, unsigned long dir) { } 75 static inline void prevent_user_access(unsigned long dir) { } 76 static inline unsigned long prevent_user_access_return(void) { return 0UL; } 77 static inline void restore_user_access(unsigned long flags) { } 78 #endif /* CONFIG_PPC_BOOK3S_64 */ 79 #endif /* CONFIG_PPC_KUAP */ 80 81 static __always_inline void setup_kup(void) 82 { 83 setup_kuep(disable_kuep); 84 setup_kuap(disable_kuap); 85 } 86 87 static __always_inline void allow_read_from_user(const void __user *from, unsigned long size) 88 { 89 barrier_nospec(); 90 allow_user_access(NULL, from, size, KUAP_READ); 91 } 92 93 static __always_inline void allow_write_to_user(void __user *to, unsigned long size) 94 { 95 allow_user_access(to, NULL, size, KUAP_WRITE); 96 } 97 98 static __always_inline void allow_read_write_user(void __user *to, const void __user *from, 99 unsigned long size) 100 { 101 barrier_nospec(); 102 allow_user_access(to, from, size, KUAP_READ_WRITE); 103 } 104 105 static __always_inline void prevent_read_from_user(const void __user *from, unsigned long size) 106 { 107 prevent_user_access(KUAP_READ); 108 } 109 110 static __always_inline void prevent_write_to_user(void __user *to, unsigned long size) 111 { 112 prevent_user_access(KUAP_WRITE); 113 } 114 115 static __always_inline void prevent_read_write_user(void __user *to, const void __user *from, 116 unsigned long size) 117 { 118 prevent_user_access(KUAP_READ_WRITE); 119 } 120 121 static __always_inline void prevent_current_access_user(void) 122 { 123 prevent_user_access(KUAP_READ_WRITE); 124 } 125 126 static __always_inline void prevent_current_read_from_user(void) 127 { 128 prevent_user_access(KUAP_READ); 129 } 130 131 static __always_inline void prevent_current_write_to_user(void) 132 { 133 prevent_user_access(KUAP_WRITE); 134 } 135 136 #endif /* !__ASSEMBLY__ */ 137 138 #endif /* _ASM_POWERPC_KUAP_H_ */ 139