arch/powerpc/include/asm/kup.h

   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_PPC64
  18 #include <asm/book3s/64/kup-radix.h>
  19 #endif
  20 #ifdef CONFIG_PPC_8xx
  21 #include <asm/nohash/32/kup-8xx.h>
  22 #endif
  23 #ifdef CONFIG_PPC_BOOK3S_32
  24 #include <asm/book3s/32/kup.h>
  25 #endif
  26
  27 #ifdef __ASSEMBLY__
  28 #ifndef CONFIG_PPC_KUAP
  29 .macro kuap_save_and_lock       sp, thread, gpr1, gpr2, gpr3
  30 .endm
  31
  32 .macro kuap_restore     sp, current, gpr1, gpr2, gpr3
  33 .endm
  34
  35 .macro kuap_check       current, gpr
  36 .endm
  37
  38 #endif
  39
  40 #else /* !__ASSEMBLY__ */
  41
  42 #include <asm/pgtable.h>
  43
  44 void setup_kup(void);
  45
  46 #ifdef CONFIG_PPC_KUEP
  47 void setup_kuep(bool disabled);
  48 #else
  49 static inline void setup_kuep(bool disabled) { }
  50 #endif /* CONFIG_PPC_KUEP */
  51
  52 #ifdef CONFIG_PPC_KUAP
  53 void setup_kuap(bool disabled);
  54 #else
  55 static inline void setup_kuap(bool disabled) { }
  56 static inline void allow_user_access(void __user *to, const void __user *from,
  57                                      unsigned long size, unsigned long dir) { }
  58 static inline void prevent_user_access(void __user *to, const void __user *from,
  59                                        unsigned long size, unsigned long dir) { }
  60 static inline unsigned long prevent_user_access_return(void) { return 0UL; }
  61 static inline void restore_user_access(unsigned long flags) { }
  62 static inline bool
  63 bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
  64 {
  65         return false;
  66 }
  67 #endif /* CONFIG_PPC_KUAP */
  68
  69 static inline void allow_read_from_user(const void __user *from, unsigned long size)
  70 {
  71         allow_user_access(NULL, from, size, KUAP_READ);
  72 }
  73
  74 static inline void allow_write_to_user(void __user *to, unsigned long size)
  75 {
  76         allow_user_access(to, NULL, size, KUAP_WRITE);
  77 }
  78
  79 static inline void allow_read_write_user(void __user *to, const void __user *from,
  80                                          unsigned long size)
  81 {
  82         allow_user_access(to, from, size, KUAP_READ_WRITE);
  83 }
  84
  85 static inline void prevent_read_from_user(const void __user *from, unsigned long size)
  86 {
  87         prevent_user_access(NULL, from, size, KUAP_READ);
  88 }
  89
  90 static inline void prevent_write_to_user(void __user *to, unsigned long size)
  91 {
  92         prevent_user_access(to, NULL, size, KUAP_WRITE);
  93 }
  94
  95 static inline void prevent_read_write_user(void __user *to, const void __user *from,
  96                                            unsigned long size)
  97 {
  98         prevent_user_access(to, from, size, KUAP_READ_WRITE);
  99 }
 100
 101 static inline void prevent_current_access_user(void)
 102 {
 103         prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT);
 104 }
 105
 106 static inline void prevent_current_read_from_user(void)
 107 {
 108         prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT_READ);
 109 }
 110
 111 static inline void prevent_current_write_to_user(void)
 112 {
 113         prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT_WRITE);
 114 }
 115
 116 #endif /* !__ASSEMBLY__ */
 117
 118 #endif /* _ASM_POWERPC_KUAP_H_ */