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 #ifndef __ASSEMBLER__
10 #include <linux/types.h>
11
12 static __always_inline bool kuap_is_disabled(void);
13 #endif
14
15 #ifdef CONFIG_PPC_BOOK3S_64
16 #include <asm/book3s/64/kup.h>
17 #endif
18
19 #ifdef CONFIG_PPC_8xx
20 #include <asm/nohash/32/kup-8xx.h>
21 #endif
22
23 #ifdef CONFIG_BOOKE
24 #include <asm/nohash/kup-booke.h>
25 #endif
26
27 #ifdef CONFIG_PPC_BOOK3S_32
28 #include <asm/book3s/32/kup.h>
29 #endif
30
31 #ifdef __ASSEMBLER__
32 #ifndef CONFIG_PPC_KUAP
33 .macro kuap_check_amr gpr1, gpr2
34 .endm
35
36 #endif
37
38 #else /* !__ASSEMBLER__ */
39
40 extern bool disable_kuep;
41 extern bool disable_kuap;
42
43 #include <linux/pgtable.h>
44
45 void setup_kup(void);
46 void setup_kuep(bool disabled);
47
48 #ifdef CONFIG_PPC_KUAP
49 void setup_kuap(bool disabled);
50
kuap_is_disabled(void)51 static __always_inline bool kuap_is_disabled(void)
52 {
53 return !mmu_has_feature(MMU_FTR_KUAP);
54 }
55 #else
setup_kuap(bool disabled)56 static inline void setup_kuap(bool disabled) { }
57
kuap_is_disabled(void)58 static __always_inline bool kuap_is_disabled(void) { return true; }
59
60 static __always_inline bool
__bad_kuap_fault(struct pt_regs * regs,unsigned long address,bool is_write)61 __bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
62 {
63 return false;
64 }
65
kuap_user_restore(struct pt_regs * regs)66 static __always_inline void kuap_user_restore(struct pt_regs *regs) { }
__kuap_kernel_restore(struct pt_regs * regs,unsigned long amr)67 static __always_inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { }
68
69 /*
70 * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush
71 * the L1D cache after user accesses. Only include the empty stubs for other
72 * platforms.
73 */
74 #ifndef CONFIG_PPC_BOOK3S_64
allow_user_access(void __user * to,unsigned long dir)75 static __always_inline void allow_user_access(void __user *to, unsigned long dir) { }
prevent_user_access(unsigned long dir)76 static __always_inline void prevent_user_access(unsigned long dir) { }
prevent_user_access_return(void)77 static __always_inline unsigned long prevent_user_access_return(void) { return 0UL; }
restore_user_access(unsigned long flags)78 static __always_inline void restore_user_access(unsigned long flags) { }
79 #endif /* CONFIG_PPC_BOOK3S_64 */
80 #endif /* CONFIG_PPC_KUAP */
81
82 static __always_inline bool
bad_kuap_fault(struct pt_regs * regs,unsigned long address,bool is_write)83 bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
84 {
85 if (kuap_is_disabled())
86 return false;
87
88 return __bad_kuap_fault(regs, address, is_write);
89 }
90
kuap_lock(void)91 static __always_inline void kuap_lock(void)
92 {
93 #ifdef __kuap_lock
94 if (kuap_is_disabled())
95 return;
96
97 __kuap_lock();
98 #endif
99 }
100
kuap_save_and_lock(struct pt_regs * regs)101 static __always_inline void kuap_save_and_lock(struct pt_regs *regs)
102 {
103 #ifdef __kuap_save_and_lock
104 if (kuap_is_disabled())
105 return;
106
107 __kuap_save_and_lock(regs);
108 #endif
109 }
110
kuap_kernel_restore(struct pt_regs * regs,unsigned long amr)111 static __always_inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long amr)
112 {
113 if (kuap_is_disabled())
114 return;
115
116 __kuap_kernel_restore(regs, amr);
117 }
118
kuap_get_and_assert_locked(void)119 static __always_inline unsigned long kuap_get_and_assert_locked(void)
120 {
121 #ifdef __kuap_get_and_assert_locked
122 if (!kuap_is_disabled())
123 return __kuap_get_and_assert_locked();
124 #endif
125 return 0;
126 }
127
kuap_assert_locked(void)128 static __always_inline void kuap_assert_locked(void)
129 {
130 if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG))
131 kuap_get_and_assert_locked();
132 }
133
134 #endif /* !__ASSEMBLER__ */
135
136 #endif /* _ASM_POWERPC_KUAP_H_ */
137