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 * For prevent_user_access() only. 10 * Use the current saved situation instead of the to/from/size params. 11 * Used on book3s/32 12 */ 13 #define KUAP_CURRENT_READ 4 14 #define KUAP_CURRENT_WRITE 8 15 #define KUAP_CURRENT (KUAP_CURRENT_READ | KUAP_CURRENT_WRITE) 16 17 #ifdef CONFIG_PPC_BOOK3S_64 18 #include <asm/book3s/64/kup.h> 19 #endif 20 21 #ifdef CONFIG_PPC_8xx 22 #include <asm/nohash/32/kup-8xx.h> 23 #endif 24 25 #ifdef CONFIG_PPC_BOOK3S_32 26 #include <asm/book3s/32/kup.h> 27 #endif 28 29 #ifdef __ASSEMBLY__ 30 #ifndef CONFIG_PPC_KUAP 31 .macro kuap_save_and_lock sp, thread, gpr1, gpr2, gpr3 32 .endm 33 34 .macro kuap_restore sp, current, gpr1, gpr2, gpr3 35 .endm 36 37 .macro kuap_check current, gpr 38 .endm 39 40 .macro kuap_check_amr gpr1, gpr2 41 .endm 42 43 #endif 44 45 #else /* !__ASSEMBLY__ */ 46 47 extern bool disable_kuep; 48 extern bool disable_kuap; 49 50 #include <linux/pgtable.h> 51 52 #ifdef CONFIG_PPC_KUEP 53 void setup_kuep(bool disabled); 54 #else 55 static inline void setup_kuep(bool disabled) { } 56 #endif /* CONFIG_PPC_KUEP */ 57 58 #ifdef CONFIG_PPC_KUAP 59 void setup_kuap(bool disabled); 60 #else 61 static inline void setup_kuap(bool disabled) { } 62 63 static inline bool 64 bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) 65 { 66 return false; 67 } 68 69 static inline void kuap_check_amr(void) { } 70 71 /* 72 * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush 73 * the L1D cache after user accesses. Only include the empty stubs for other 74 * platforms. 75 */ 76 #ifndef CONFIG_PPC_BOOK3S_64 77 static inline void allow_user_access(void __user *to, const void __user *from, 78 unsigned long size, unsigned long dir) { } 79 static inline void prevent_user_access(void __user *to, const void __user *from, 80 unsigned long size, unsigned long dir) { } 81 static inline unsigned long prevent_user_access_return(void) { return 0UL; } 82 static inline void restore_user_access(unsigned long flags) { } 83 #endif /* CONFIG_PPC_BOOK3S_64 */ 84 #endif /* CONFIG_PPC_KUAP */ 85 86 static __always_inline void setup_kup(void) 87 { 88 setup_kuep(disable_kuep); 89 setup_kuap(disable_kuap); 90 } 91 92 static inline void allow_read_from_user(const void __user *from, unsigned long size) 93 { 94 allow_user_access(NULL, from, size, KUAP_READ); 95 } 96 97 static inline void allow_write_to_user(void __user *to, unsigned long size) 98 { 99 allow_user_access(to, NULL, size, KUAP_WRITE); 100 } 101 102 static inline void allow_read_write_user(void __user *to, const void __user *from, 103 unsigned long size) 104 { 105 allow_user_access(to, from, size, KUAP_READ_WRITE); 106 } 107 108 static inline void prevent_read_from_user(const void __user *from, unsigned long size) 109 { 110 prevent_user_access(NULL, from, size, KUAP_READ); 111 } 112 113 static inline void prevent_write_to_user(void __user *to, unsigned long size) 114 { 115 prevent_user_access(to, NULL, size, KUAP_WRITE); 116 } 117 118 static inline void prevent_read_write_user(void __user *to, const void __user *from, 119 unsigned long size) 120 { 121 prevent_user_access(to, from, size, KUAP_READ_WRITE); 122 } 123 124 static inline void prevent_current_access_user(void) 125 { 126 prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT); 127 } 128 129 static inline void prevent_current_read_from_user(void) 130 { 131 prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT_READ); 132 } 133 134 static inline void prevent_current_write_to_user(void) 135 { 136 prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT_WRITE); 137 } 138 139 #endif /* !__ASSEMBLY__ */ 140 141 #endif /* _ASM_POWERPC_KUAP_H_ */ 142