xref: /linux/tools/testing/selftests/mm/pkey-helpers.h (revision 04d0c0092b427dd28f57b57f001be9110cb5acfe)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _PKEYS_HELPER_H
3 #define _PKEYS_HELPER_H
4 #define _GNU_SOURCE
5 #include <string.h>
6 #include <stdarg.h>
7 #include <stdio.h>
8 #include <stdint.h>
9 #include <stdbool.h>
10 #include <signal.h>
11 #include <assert.h>
12 #include <stdlib.h>
13 #include <ucontext.h>
14 #include <sys/mman.h>
15 
16 #include <linux/mman.h>
17 #include <linux/types.h>
18 
19 #include "kselftest.h"
20 
21 /* Define some kernel-like types */
22 typedef __u8	u8;
23 typedef __u16	u16;
24 typedef __u32	u32;
25 typedef __u64	u64;
26 
27 #define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
28 
29 #ifndef DEBUG_LEVEL
30 #define DEBUG_LEVEL 0
31 #endif
32 extern int dprint_in_signal;
33 
34 extern int test_nr;
35 extern int iteration_nr;
36 
37 #ifdef __GNUC__
38 __printf(1, 2)
39 #endif
40 static inline void sigsafe_printf(const char *format, ...)
41 {
42 	va_list ap;
43 
44 	if (!dprint_in_signal) {
45 		va_start(ap, format);
46 		vprintf(format, ap);
47 		va_end(ap);
48 	} else {
49 		int ret;
50 		/*
51 		 * No printf() functions are signal-safe.
52 		 * They deadlock easily. Write the format
53 		 * string to get some output, even if
54 		 * incomplete.
55 		 */
56 		ret = write(1, format, strlen(format));
57 		if (ret < 0)
58 			exit(1);
59 	}
60 }
61 #define dprintf_level(level, args...) do {	\
62 	if (level <= DEBUG_LEVEL)		\
63 		sigsafe_printf(args);		\
64 } while (0)
65 #define dprintf0(args...) dprintf_level(0, args)
66 #define dprintf1(args...) dprintf_level(1, args)
67 #define dprintf2(args...) dprintf_level(2, args)
68 #define dprintf3(args...) dprintf_level(3, args)
69 #define dprintf4(args...) dprintf_level(4, args)
70 
71 extern void abort_hooks(void);
72 #define pkey_assert(condition) do {		\
73 	if (!(condition)) {			\
74 		dprintf0("# assert() at %s::%d test_nr: %d iteration: %d\n", \
75 			 __FILE__, __LINE__,				\
76 			 test_nr, iteration_nr);			\
77 		dprintf0("# errno at assert: %d\n", errno);		\
78 		abort_hooks();						\
79 		ksft_exit_fail_msg("test %d (iteration %d)\n",		\
80 				   test_nr, iteration_nr);		\
81 	}								\
82 } while (0)
83 
84 #define barrier() __asm__ __volatile__("": : :"memory")
85 #ifndef noinline
86 # define noinline __attribute__((noinline))
87 #endif
88 
89 int sys_pkey_alloc(unsigned long flags, unsigned long init_val);
90 int sys_pkey_free(unsigned long pkey);
91 int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
92 		unsigned long pkey);
93 
94 /* For functions called from protection_keys.c only */
95 noinline int read_ptr(int *ptr);
96 void expected_pkey_fault(int pkey);
97 int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
98 		unsigned long pkey);
99 void record_pkey_malloc(void *ptr, long size, int prot);
100 
101 #if defined(__i386__) || defined(__x86_64__) /* arch */
102 #include "pkey-x86.h"
103 #elif defined(__powerpc64__) /* arch */
104 #include "pkey-powerpc.h"
105 #elif defined(__aarch64__) /* arch */
106 #include "pkey-arm64.h"
107 #else /* arch */
108 #error Architecture not supported
109 #endif /* arch */
110 
111 #ifndef PKEY_MASK
112 #define PKEY_MASK	(PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)
113 #endif
114 
115 /*
116  * FIXME: Remove once the generic PKEY_UNRESTRICTED definition is merged.
117  */
118 #ifndef PKEY_UNRESTRICTED
119 #define PKEY_UNRESTRICTED 0x0
120 #endif
121 
122 #ifndef set_pkey_bits
123 static inline u64 set_pkey_bits(u64 reg, int pkey, u64 flags)
124 {
125 	u32 shift = pkey_bit_position(pkey);
126 	/* mask out bits from pkey in old value */
127 	reg &= ~((u64)PKEY_MASK << shift);
128 	/* OR in new bits for pkey */
129 	reg |= (flags & PKEY_MASK) << shift;
130 	return reg;
131 }
132 #endif
133 
134 #ifndef get_pkey_bits
135 static inline u64 get_pkey_bits(u64 reg, int pkey)
136 {
137 	u32 shift = pkey_bit_position(pkey);
138 	/*
139 	 * shift down the relevant bits to the lowest two, then
140 	 * mask off all the other higher bits
141 	 */
142 	return ((reg >> shift) & PKEY_MASK);
143 }
144 #endif
145 
146 extern u64 shadow_pkey_reg;
147 
148 static inline u64 _read_pkey_reg(int line)
149 {
150 	u64 pkey_reg = __read_pkey_reg();
151 
152 	dprintf4("read_pkey_reg(line=%d) pkey_reg: %016llx"
153 			" shadow: %016llx\n",
154 			line, pkey_reg, shadow_pkey_reg);
155 	assert(pkey_reg == shadow_pkey_reg);
156 
157 	return pkey_reg;
158 }
159 
160 #define read_pkey_reg() _read_pkey_reg(__LINE__)
161 
162 static inline void write_pkey_reg(u64 pkey_reg)
163 {
164 	dprintf4("%s() changing %016llx to %016llx\n", __func__,
165 			__read_pkey_reg(), pkey_reg);
166 	/* will do the shadow check for us: */
167 	read_pkey_reg();
168 	__write_pkey_reg(pkey_reg);
169 	shadow_pkey_reg = pkey_reg;
170 	dprintf4("%s(%016llx) pkey_reg: %016llx\n", __func__,
171 			pkey_reg, __read_pkey_reg());
172 }
173 
174 #define ALIGN_UP(x, align_to)	(((x) + ((align_to)-1)) & ~((align_to)-1))
175 #define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
176 #define ALIGN_PTR_UP(p, ptr_align_to)	\
177 	((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
178 #define ALIGN_PTR_DOWN(p, ptr_align_to)	\
179 	((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
180 #define __stringify_1(x...)     #x
181 #define __stringify(x...)       __stringify_1(x)
182 
183 static inline u32 *siginfo_get_pkey_ptr(siginfo_t *si)
184 {
185 #ifdef si_pkey
186 	return &si->si_pkey;
187 #else
188 	return (u32 *)(((u8 *)si) + si_pkey_offset);
189 #endif
190 }
191 
192 static inline int kernel_has_pkeys(void)
193 {
194 	/* try allocating a key and see if it succeeds */
195 	int ret = sys_pkey_alloc(0, PKEY_UNRESTRICTED);
196 	if (ret <= 0) {
197 		return 0;
198 	}
199 	sys_pkey_free(ret);
200 	return 1;
201 }
202 
203 static inline int is_pkeys_supported(void)
204 {
205 	/* check if the cpu supports pkeys */
206 	if (!cpu_has_pkeys()) {
207 		dprintf1("SKIP: %s: no CPU support\n", __func__);
208 		return 0;
209 	}
210 
211 	/* check if the kernel supports pkeys */
212 	if (!kernel_has_pkeys()) {
213 		dprintf1("SKIP: %s: no kernel support\n", __func__);
214 		return 0;
215 	}
216 
217 	return 1;
218 }
219 
220 #endif /* _PKEYS_HELPER_H */
221