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 /* Define some kernel-like types */
17 #define u8 __u8
18 #define u16 __u16
19 #define u32 __u32
20 #define u64 __u64
21
22 #define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)
23
24 #ifndef DEBUG_LEVEL
25 #define DEBUG_LEVEL 0
26 #endif
27 #define DPRINT_IN_SIGNAL_BUF_SIZE 4096
28 extern int dprint_in_signal;
29 extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
30
31 extern int test_nr;
32 extern int iteration_nr;
33
34 #ifdef __GNUC__
35 __attribute__((format(printf, 1, 2)))
36 #endif
sigsafe_printf(const char * format,...)37 static inline void sigsafe_printf(const char *format, ...)
38 {
39 va_list ap;
40
41 if (!dprint_in_signal) {
42 va_start(ap, format);
43 vprintf(format, ap);
44 va_end(ap);
45 } else {
46 int ret;
47 /*
48 * No printf() functions are signal-safe.
49 * They deadlock easily. Write the format
50 * string to get some output, even if
51 * incomplete.
52 */
53 ret = write(1, format, strlen(format));
54 if (ret < 0)
55 exit(1);
56 }
57 }
58 #define dprintf_level(level, args...) do { \
59 if (level <= DEBUG_LEVEL) \
60 sigsafe_printf(args); \
61 } while (0)
62 #define dprintf0(args...) dprintf_level(0, args)
63 #define dprintf1(args...) dprintf_level(1, args)
64 #define dprintf2(args...) dprintf_level(2, args)
65 #define dprintf3(args...) dprintf_level(3, args)
66 #define dprintf4(args...) dprintf_level(4, args)
67
68 extern void abort_hooks(void);
69 #define pkey_assert(condition) do { \
70 if (!(condition)) { \
71 dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
72 __FILE__, __LINE__, \
73 test_nr, iteration_nr); \
74 dprintf0("errno at assert: %d", errno); \
75 abort_hooks(); \
76 exit(__LINE__); \
77 } \
78 } while (0)
79
80 __attribute__((noinline)) int read_ptr(int *ptr);
81 void expected_pkey_fault(int pkey);
82 int sys_pkey_alloc(unsigned long flags, unsigned long init_val);
83 int sys_pkey_free(unsigned long pkey);
84 int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
85 unsigned long pkey);
86 void record_pkey_malloc(void *ptr, long size, int prot);
87
88 #if defined(__i386__) || defined(__x86_64__) /* arch */
89 #include "pkey-x86.h"
90 #elif defined(__powerpc64__) /* arch */
91 #include "pkey-powerpc.h"
92 #else /* arch */
93 #error Architecture not supported
94 #endif /* arch */
95
96 #define PKEY_MASK (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)
97
set_pkey_bits(u64 reg,int pkey,u64 flags)98 static inline u64 set_pkey_bits(u64 reg, int pkey, u64 flags)
99 {
100 u32 shift = pkey_bit_position(pkey);
101 /* mask out bits from pkey in old value */
102 reg &= ~((u64)PKEY_MASK << shift);
103 /* OR in new bits for pkey */
104 reg |= (flags & PKEY_MASK) << shift;
105 return reg;
106 }
107
get_pkey_bits(u64 reg,int pkey)108 static inline u64 get_pkey_bits(u64 reg, int pkey)
109 {
110 u32 shift = pkey_bit_position(pkey);
111 /*
112 * shift down the relevant bits to the lowest two, then
113 * mask off all the other higher bits
114 */
115 return ((reg >> shift) & PKEY_MASK);
116 }
117
118 extern u64 shadow_pkey_reg;
119
_read_pkey_reg(int line)120 static inline u64 _read_pkey_reg(int line)
121 {
122 u64 pkey_reg = __read_pkey_reg();
123
124 dprintf4("read_pkey_reg(line=%d) pkey_reg: %016llx"
125 " shadow: %016llx\n",
126 line, pkey_reg, shadow_pkey_reg);
127 assert(pkey_reg == shadow_pkey_reg);
128
129 return pkey_reg;
130 }
131
132 #define read_pkey_reg() _read_pkey_reg(__LINE__)
133
write_pkey_reg(u64 pkey_reg)134 static inline void write_pkey_reg(u64 pkey_reg)
135 {
136 dprintf4("%s() changing %016llx to %016llx\n", __func__,
137 __read_pkey_reg(), pkey_reg);
138 /* will do the shadow check for us: */
139 read_pkey_reg();
140 __write_pkey_reg(pkey_reg);
141 shadow_pkey_reg = pkey_reg;
142 dprintf4("%s(%016llx) pkey_reg: %016llx\n", __func__,
143 pkey_reg, __read_pkey_reg());
144 }
145
146 /*
147 * These are technically racy. since something could
148 * change PKEY register between the read and the write.
149 */
__pkey_access_allow(int pkey,int do_allow)150 static inline void __pkey_access_allow(int pkey, int do_allow)
151 {
152 u64 pkey_reg = read_pkey_reg();
153 int bit = pkey * 2;
154
155 if (do_allow)
156 pkey_reg &= (1<<bit);
157 else
158 pkey_reg |= (1<<bit);
159
160 dprintf4("pkey_reg now: %016llx\n", read_pkey_reg());
161 write_pkey_reg(pkey_reg);
162 }
163
__pkey_write_allow(int pkey,int do_allow_write)164 static inline void __pkey_write_allow(int pkey, int do_allow_write)
165 {
166 u64 pkey_reg = read_pkey_reg();
167 int bit = pkey * 2 + 1;
168
169 if (do_allow_write)
170 pkey_reg &= (1<<bit);
171 else
172 pkey_reg |= (1<<bit);
173
174 write_pkey_reg(pkey_reg);
175 dprintf4("pkey_reg now: %016llx\n", read_pkey_reg());
176 }
177
178 #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
179 #define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))
180 #define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
181 #define ALIGN_PTR_UP(p, ptr_align_to) \
182 ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))
183 #define ALIGN_PTR_DOWN(p, ptr_align_to) \
184 ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))
185 #define __stringify_1(x...) #x
186 #define __stringify(x...) __stringify_1(x)
187
siginfo_get_pkey_ptr(siginfo_t * si)188 static inline u32 *siginfo_get_pkey_ptr(siginfo_t *si)
189 {
190 #ifdef si_pkey
191 return &si->si_pkey;
192 #else
193 return (u32 *)(((u8 *)si) + si_pkey_offset);
194 #endif
195 }
196
kernel_has_pkeys(void)197 static inline int kernel_has_pkeys(void)
198 {
199 /* try allocating a key and see if it succeeds */
200 int ret = sys_pkey_alloc(0, 0);
201 if (ret <= 0) {
202 return 0;
203 }
204 sys_pkey_free(ret);
205 return 1;
206 }
207
is_pkeys_supported(void)208 static inline int is_pkeys_supported(void)
209 {
210 /* check if the cpu supports pkeys */
211 if (!cpu_has_pkeys()) {
212 dprintf1("SKIP: %s: no CPU support\n", __func__);
213 return 0;
214 }
215
216 /* check if the kernel supports pkeys */
217 if (!kernel_has_pkeys()) {
218 dprintf1("SKIP: %s: no kernel support\n", __func__);
219 return 0;
220 }
221
222 return 1;
223 }
224
225 #endif /* _PKEYS_HELPER_H */
226