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