xref: /openbmc/linux/tools/testing/selftests/mm/pkey-helpers.h (revision 9a87ffc99ec8eb8d35eed7c4f816d75f5cc9662e)
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
30  extern int dprint_in_signal;
31  extern char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
32  
33  extern int test_nr;
34  extern int iteration_nr;
35  
36  #ifdef __GNUC__
37  __attribute__((format(printf, 1, 2)))
38  #endif
sigsafe_printf(const char * format,...)39  static 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  
70  extern 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);
83  void expected_pkey_fault(int pkey);
84  int sys_pkey_alloc(unsigned long flags, unsigned long init_val);
85  int sys_pkey_free(unsigned long pkey);
86  int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
87  		unsigned long pkey);
88  void 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  
set_pkey_bits(u64 reg,int pkey,u64 flags)100  static 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  
get_pkey_bits(u64 reg,int pkey)110  static 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  
120  extern u64 shadow_pkey_reg;
121  
_read_pkey_reg(int line)122  static 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  
write_pkey_reg(u64 pkey_reg)136  static 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   */
__pkey_access_allow(int pkey,int do_allow)152  static 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  
__pkey_write_allow(int pkey,int do_allow_write)166  static 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  
siginfo_get_pkey_ptr(siginfo_t * si)189  static 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  
kernel_has_pkeys(void)198  static 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  
is_pkeys_supported(void)209  static 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 */
227