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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _PKEYS_HELPER_H3#define _PKEYS_HELPER_H4#define _GNU_SOURCE5#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 __u820#define u16 __u1621#define u32 __u3222#define u64 __u6423 24#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)25 26#ifndef DEBUG_LEVEL27#define DEBUG_LEVEL 028#endif29#define DPRINT_IN_SIGNAL_BUF_SIZE 409630extern 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#endif39static 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 format52 * string to get some output, even if53 * 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#define barrier() __asm__ __volatile__("": : :"memory")83#ifndef noinline84# define noinline __attribute__((noinline))85#endif86 87noinline int read_ptr(int *ptr)88{89 /* Keep GCC from optimizing this away somehow */90 barrier();91 return *ptr;92}93 94void expected_pkey_fault(int pkey);95int sys_pkey_alloc(unsigned long flags, unsigned long init_val);96int sys_pkey_free(unsigned long pkey);97int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,98 unsigned long pkey);99void 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 supported109#endif /* arch */110 111#ifndef PKEY_MASK112#define PKEY_MASK (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)113#endif114 115#ifndef set_pkey_bits116static inline u64 set_pkey_bits(u64 reg, int pkey, u64 flags)117{118 u32 shift = pkey_bit_position(pkey);119 /* mask out bits from pkey in old value */120 reg &= ~((u64)PKEY_MASK << shift);121 /* OR in new bits for pkey */122 reg |= (flags & PKEY_MASK) << shift;123 return reg;124}125#endif126 127#ifndef get_pkey_bits128static inline u64 get_pkey_bits(u64 reg, int pkey)129{130 u32 shift = pkey_bit_position(pkey);131 /*132 * shift down the relevant bits to the lowest two, then133 * mask off all the other higher bits134 */135 return ((reg >> shift) & PKEY_MASK);136}137#endif138 139extern u64 shadow_pkey_reg;140 141static inline u64 _read_pkey_reg(int line)142{143 u64 pkey_reg = __read_pkey_reg();144 145 dprintf4("read_pkey_reg(line=%d) pkey_reg: %016llx"146 " shadow: %016llx\n",147 line, pkey_reg, shadow_pkey_reg);148 assert(pkey_reg == shadow_pkey_reg);149 150 return pkey_reg;151}152 153#define read_pkey_reg() _read_pkey_reg(__LINE__)154 155static inline void write_pkey_reg(u64 pkey_reg)156{157 dprintf4("%s() changing %016llx to %016llx\n", __func__,158 __read_pkey_reg(), pkey_reg);159 /* will do the shadow check for us: */160 read_pkey_reg();161 __write_pkey_reg(pkey_reg);162 shadow_pkey_reg = pkey_reg;163 dprintf4("%s(%016llx) pkey_reg: %016llx\n", __func__,164 pkey_reg, __read_pkey_reg());165}166 167/*168 * These are technically racy. since something could169 * change PKEY register between the read and the write.170 */171static inline void __pkey_access_allow(int pkey, int do_allow)172{173 u64 pkey_reg = read_pkey_reg();174 int bit = pkey * 2;175 176 if (do_allow)177 pkey_reg &= (1<<bit);178 else179 pkey_reg |= (1<<bit);180 181 dprintf4("pkey_reg now: %016llx\n", read_pkey_reg());182 write_pkey_reg(pkey_reg);183}184 185static inline void __pkey_write_allow(int pkey, int do_allow_write)186{187 u64 pkey_reg = read_pkey_reg();188 int bit = pkey * 2 + 1;189 190 if (do_allow_write)191 pkey_reg &= (1<<bit);192 else193 pkey_reg |= (1<<bit);194 195 write_pkey_reg(pkey_reg);196 dprintf4("pkey_reg now: %016llx\n", read_pkey_reg());197}198 199#define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1))200#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))201#define ALIGN_PTR_UP(p, ptr_align_to) \202 ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to))203#define ALIGN_PTR_DOWN(p, ptr_align_to) \204 ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to))205#define __stringify_1(x...) #x206#define __stringify(x...) __stringify_1(x)207 208static inline u32 *siginfo_get_pkey_ptr(siginfo_t *si)209{210#ifdef si_pkey211 return &si->si_pkey;212#else213 return (u32 *)(((u8 *)si) + si_pkey_offset);214#endif215}216 217static inline int kernel_has_pkeys(void)218{219 /* try allocating a key and see if it succeeds */220 int ret = sys_pkey_alloc(0, 0);221 if (ret <= 0) {222 return 0;223 }224 sys_pkey_free(ret);225 return 1;226}227 228static inline int is_pkeys_supported(void)229{230 /* check if the cpu supports pkeys */231 if (!cpu_has_pkeys()) {232 dprintf1("SKIP: %s: no CPU support\n", __func__);233 return 0;234 }235 236 /* check if the kernel supports pkeys */237 if (!kernel_has_pkeys()) {238 dprintf1("SKIP: %s: no kernel support\n", __func__);239 return 0;240 }241 242 return 1;243}244 245#endif /* _PKEYS_HELPER_H */246