Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 2 | /* |
| 3 | * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt) |
| 4 | * |
| 5 | * There are examples in here of: |
| 6 | * * how to set protection keys on memory |
| 7 | * * how to set/clear bits in PKRU (the rights register) |
| 8 | * * how to handle SEGV_PKRU signals and extract pkey-relevant |
| 9 | * information from the siginfo |
| 10 | * |
| 11 | * Things to add: |
| 12 | * make sure KSM and KSM COW breaking works |
| 13 | * prefault pages in at malloc, or not |
| 14 | * protect MPX bounds tables with protection keys? |
| 15 | * make sure VMA splitting/merging is working correctly |
| 16 | * OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys |
| 17 | * look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel |
| 18 | * do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks |
| 19 | * |
| 20 | * Compile like this: |
| 21 | * gcc -o protection_keys -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm |
| 22 | * gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm |
| 23 | */ |
| 24 | #define _GNU_SOURCE |
| 25 | #include <errno.h> |
| 26 | #include <linux/futex.h> |
| 27 | #include <sys/time.h> |
| 28 | #include <sys/syscall.h> |
| 29 | #include <string.h> |
| 30 | #include <stdio.h> |
| 31 | #include <stdint.h> |
| 32 | #include <stdbool.h> |
| 33 | #include <signal.h> |
| 34 | #include <assert.h> |
| 35 | #include <stdlib.h> |
| 36 | #include <ucontext.h> |
| 37 | #include <sys/mman.h> |
| 38 | #include <sys/types.h> |
| 39 | #include <sys/wait.h> |
| 40 | #include <sys/stat.h> |
| 41 | #include <fcntl.h> |
| 42 | #include <unistd.h> |
| 43 | #include <sys/ptrace.h> |
| 44 | #include <setjmp.h> |
| 45 | |
| 46 | #include "pkey-helpers.h" |
| 47 | |
| 48 | int iteration_nr = 1; |
| 49 | int test_nr; |
| 50 | |
| 51 | unsigned int shadow_pkru; |
| 52 | |
| 53 | #define HPAGE_SIZE (1UL<<21) |
| 54 | #define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) |
| 55 | #define ALIGN_UP(x, align_to) (((x) + ((align_to)-1)) & ~((align_to)-1)) |
| 56 | #define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1)) |
| 57 | #define ALIGN_PTR_UP(p, ptr_align_to) ((typeof(p))ALIGN_UP((unsigned long)(p), ptr_align_to)) |
| 58 | #define ALIGN_PTR_DOWN(p, ptr_align_to) ((typeof(p))ALIGN_DOWN((unsigned long)(p), ptr_align_to)) |
| 59 | #define __stringify_1(x...) #x |
| 60 | #define __stringify(x...) __stringify_1(x) |
| 61 | |
| 62 | #define PTR_ERR_ENOTSUP ((void *)-ENOTSUP) |
| 63 | |
| 64 | int dprint_in_signal; |
| 65 | char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE]; |
| 66 | |
| 67 | extern void abort_hooks(void); |
| 68 | #define pkey_assert(condition) do { \ |
| 69 | if (!(condition)) { \ |
| 70 | dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \ |
| 71 | __FILE__, __LINE__, \ |
| 72 | test_nr, iteration_nr); \ |
| 73 | dprintf0("errno at assert: %d", errno); \ |
| 74 | abort_hooks(); \ |
Dave Hansen | 86b9eea | 2018-05-09 10:13:40 -0700 | [diff] [blame] | 75 | exit(__LINE__); \ |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 76 | } \ |
| 77 | } while (0) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 78 | |
| 79 | void cat_into_file(char *str, char *file) |
| 80 | { |
| 81 | int fd = open(file, O_RDWR); |
| 82 | int ret; |
| 83 | |
| 84 | dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file); |
| 85 | /* |
| 86 | * these need to be raw because they are called under |
| 87 | * pkey_assert() |
| 88 | */ |
Dave Hansen | 86b9eea | 2018-05-09 10:13:40 -0700 | [diff] [blame] | 89 | if (fd < 0) { |
| 90 | fprintf(stderr, "error opening '%s'\n", str); |
| 91 | perror("error: "); |
| 92 | exit(__LINE__); |
| 93 | } |
| 94 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 95 | ret = write(fd, str, strlen(str)); |
| 96 | if (ret != strlen(str)) { |
| 97 | perror("write to file failed"); |
| 98 | fprintf(stderr, "filename: '%s' str: '%s'\n", file, str); |
Dave Hansen | 86b9eea | 2018-05-09 10:13:40 -0700 | [diff] [blame] | 99 | exit(__LINE__); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 100 | } |
| 101 | close(fd); |
| 102 | } |
| 103 | |
| 104 | #if CONTROL_TRACING > 0 |
| 105 | static int warned_tracing; |
| 106 | int tracing_root_ok(void) |
| 107 | { |
| 108 | if (geteuid() != 0) { |
| 109 | if (!warned_tracing) |
| 110 | fprintf(stderr, "WARNING: not run as root, " |
| 111 | "can not do tracing control\n"); |
| 112 | warned_tracing = 1; |
| 113 | return 0; |
| 114 | } |
| 115 | return 1; |
| 116 | } |
| 117 | #endif |
| 118 | |
| 119 | void tracing_on(void) |
| 120 | { |
| 121 | #if CONTROL_TRACING > 0 |
| 122 | #define TRACEDIR "/sys/kernel/debug/tracing" |
| 123 | char pidstr[32]; |
| 124 | |
| 125 | if (!tracing_root_ok()) |
| 126 | return; |
| 127 | |
| 128 | sprintf(pidstr, "%d", getpid()); |
| 129 | cat_into_file("0", TRACEDIR "/tracing_on"); |
| 130 | cat_into_file("\n", TRACEDIR "/trace"); |
| 131 | if (1) { |
| 132 | cat_into_file("function_graph", TRACEDIR "/current_tracer"); |
| 133 | cat_into_file("1", TRACEDIR "/options/funcgraph-proc"); |
| 134 | } else { |
| 135 | cat_into_file("nop", TRACEDIR "/current_tracer"); |
| 136 | } |
| 137 | cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid"); |
| 138 | cat_into_file("1", TRACEDIR "/tracing_on"); |
| 139 | dprintf1("enabled tracing\n"); |
| 140 | #endif |
| 141 | } |
| 142 | |
| 143 | void tracing_off(void) |
| 144 | { |
| 145 | #if CONTROL_TRACING > 0 |
| 146 | if (!tracing_root_ok()) |
| 147 | return; |
| 148 | cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on"); |
| 149 | #endif |
| 150 | } |
| 151 | |
| 152 | void abort_hooks(void) |
| 153 | { |
| 154 | fprintf(stderr, "running %s()...\n", __func__); |
| 155 | tracing_off(); |
| 156 | #ifdef SLEEP_ON_ABORT |
| 157 | sleep(SLEEP_ON_ABORT); |
| 158 | #endif |
| 159 | } |
| 160 | |
| 161 | static inline void __page_o_noops(void) |
| 162 | { |
| 163 | /* 8-bytes of instruction * 512 bytes = 1 page */ |
| 164 | asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr"); |
| 165 | } |
| 166 | |
| 167 | /* |
| 168 | * This attempts to have roughly a page of instructions followed by a few |
| 169 | * instructions that do a write, and another page of instructions. That |
| 170 | * way, we are pretty sure that the write is in the second page of |
| 171 | * instructions and has at least a page of padding behind it. |
| 172 | * |
| 173 | * *That* lets us be sure to madvise() away the write instruction, which |
| 174 | * will then fault, which makes sure that the fault code handles |
| 175 | * execute-only memory properly. |
| 176 | */ |
| 177 | __attribute__((__aligned__(PAGE_SIZE))) |
| 178 | void lots_o_noops_around_write(int *write_to_me) |
| 179 | { |
| 180 | dprintf3("running %s()\n", __func__); |
| 181 | __page_o_noops(); |
| 182 | /* Assume this happens in the second page of instructions: */ |
| 183 | *write_to_me = __LINE__; |
| 184 | /* pad out by another page: */ |
| 185 | __page_o_noops(); |
| 186 | dprintf3("%s() done\n", __func__); |
| 187 | } |
| 188 | |
| 189 | /* Define some kernel-like types */ |
| 190 | #define u8 uint8_t |
| 191 | #define u16 uint16_t |
| 192 | #define u32 uint32_t |
| 193 | #define u64 uint64_t |
| 194 | |
| 195 | #ifdef __i386__ |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 196 | |
| 197 | #ifndef SYS_mprotect_key |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 198 | # define SYS_mprotect_key 380 |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 199 | #endif |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 200 | |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 201 | #ifndef SYS_pkey_alloc |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 202 | # define SYS_pkey_alloc 381 |
| 203 | # define SYS_pkey_free 382 |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 204 | #endif |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 205 | |
| 206 | #define REG_IP_IDX REG_EIP |
| 207 | #define si_pkey_offset 0x14 |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 208 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 209 | #else |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 210 | |
| 211 | #ifndef SYS_mprotect_key |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 212 | # define SYS_mprotect_key 329 |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 213 | #endif |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 214 | |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 215 | #ifndef SYS_pkey_alloc |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 216 | # define SYS_pkey_alloc 330 |
| 217 | # define SYS_pkey_free 331 |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 218 | #endif |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 219 | |
| 220 | #define REG_IP_IDX REG_RIP |
| 221 | #define si_pkey_offset 0x20 |
Andy Lutomirski | 693cb55 | 2017-11-04 04:19:48 -0700 | [diff] [blame] | 222 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 223 | #endif |
| 224 | |
| 225 | void dump_mem(void *dumpme, int len_bytes) |
| 226 | { |
| 227 | char *c = (void *)dumpme; |
| 228 | int i; |
| 229 | |
| 230 | for (i = 0; i < len_bytes; i += sizeof(u64)) { |
| 231 | u64 *ptr = (u64 *)(c + i); |
| 232 | dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr); |
| 233 | } |
| 234 | } |
| 235 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 236 | /* Failed address bound checks: */ |
| 237 | #ifndef SEGV_BNDERR |
| 238 | # define SEGV_BNDERR 3 |
| 239 | #endif |
| 240 | |
| 241 | #ifndef SEGV_PKUERR |
| 242 | # define SEGV_PKUERR 4 |
| 243 | #endif |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 244 | |
| 245 | static char *si_code_str(int si_code) |
| 246 | { |
Eric W. Biederman | d12fe87 | 2017-06-26 16:36:57 -0500 | [diff] [blame] | 247 | if (si_code == SEGV_MAPERR) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 248 | return "SEGV_MAPERR"; |
Eric W. Biederman | d12fe87 | 2017-06-26 16:36:57 -0500 | [diff] [blame] | 249 | if (si_code == SEGV_ACCERR) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 250 | return "SEGV_ACCERR"; |
Eric W. Biederman | d12fe87 | 2017-06-26 16:36:57 -0500 | [diff] [blame] | 251 | if (si_code == SEGV_BNDERR) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 252 | return "SEGV_BNDERR"; |
Eric W. Biederman | d12fe87 | 2017-06-26 16:36:57 -0500 | [diff] [blame] | 253 | if (si_code == SEGV_PKUERR) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 254 | return "SEGV_PKUERR"; |
| 255 | return "UNKNOWN"; |
| 256 | } |
| 257 | |
| 258 | int pkru_faults; |
| 259 | int last_si_pkey = -1; |
| 260 | void signal_handler(int signum, siginfo_t *si, void *vucontext) |
| 261 | { |
| 262 | ucontext_t *uctxt = vucontext; |
| 263 | int trapno; |
| 264 | unsigned long ip; |
| 265 | char *fpregs; |
| 266 | u32 *pkru_ptr; |
Dave Hansen | 91c49c2 | 2017-11-10 16:12:31 -0800 | [diff] [blame] | 267 | u64 siginfo_pkey; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 268 | u32 *si_pkey_ptr; |
| 269 | int pkru_offset; |
| 270 | fpregset_t fpregset; |
| 271 | |
| 272 | dprint_in_signal = 1; |
| 273 | dprintf1(">>>>===============SIGSEGV============================\n"); |
| 274 | dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__, |
| 275 | __rdpkru(), shadow_pkru); |
| 276 | |
| 277 | trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO]; |
| 278 | ip = uctxt->uc_mcontext.gregs[REG_IP_IDX]; |
| 279 | fpregset = uctxt->uc_mcontext.fpregs; |
| 280 | fpregs = (void *)fpregset; |
| 281 | |
| 282 | dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__, |
| 283 | trapno, ip, si_code_str(si->si_code), si->si_code); |
| 284 | #ifdef __i386__ |
| 285 | /* |
| 286 | * 32-bit has some extra padding so that userspace can tell whether |
| 287 | * the XSTATE header is present in addition to the "legacy" FPU |
| 288 | * state. We just assume that it is here. |
| 289 | */ |
| 290 | fpregs += 0x70; |
| 291 | #endif |
| 292 | pkru_offset = pkru_xstate_offset(); |
| 293 | pkru_ptr = (void *)(&fpregs[pkru_offset]); |
| 294 | |
| 295 | dprintf1("siginfo: %p\n", si); |
| 296 | dprintf1(" fpregs: %p\n", fpregs); |
| 297 | /* |
| 298 | * If we got a PKRU fault, we *HAVE* to have at least one bit set in |
| 299 | * here. |
| 300 | */ |
| 301 | dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset()); |
| 302 | if (DEBUG_LEVEL > 4) |
| 303 | dump_mem(pkru_ptr - 128, 256); |
| 304 | pkey_assert(*pkru_ptr); |
| 305 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 306 | if ((si->si_code == SEGV_MAPERR) || |
| 307 | (si->si_code == SEGV_ACCERR) || |
| 308 | (si->si_code == SEGV_BNDERR)) { |
| 309 | printf("non-PK si_code, exiting...\n"); |
| 310 | exit(4); |
| 311 | } |
| 312 | |
Dave Hansen | 3d64f4e | 2018-05-09 10:13:52 -0700 | [diff] [blame] | 313 | si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset); |
| 314 | dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr); |
| 315 | dump_mem((u8 *)si_pkey_ptr - 8, 24); |
| 316 | siginfo_pkey = *si_pkey_ptr; |
| 317 | pkey_assert(siginfo_pkey < NR_PKEYS); |
| 318 | last_si_pkey = siginfo_pkey; |
| 319 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 320 | dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr); |
| 321 | /* need __rdpkru() version so we do not do shadow_pkru checking */ |
| 322 | dprintf1("signal pkru from pkru: %08x\n", __rdpkru()); |
Dave Hansen | 91c49c2 | 2017-11-10 16:12:31 -0800 | [diff] [blame] | 323 | dprintf1("pkey from siginfo: %jx\n", siginfo_pkey); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 324 | *(u64 *)pkru_ptr = 0x00000000; |
| 325 | dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n"); |
| 326 | pkru_faults++; |
| 327 | dprintf1("<<<<==================================================\n"); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 328 | dprint_in_signal = 0; |
| 329 | } |
| 330 | |
| 331 | int wait_all_children(void) |
| 332 | { |
| 333 | int status; |
| 334 | return waitpid(-1, &status, 0); |
| 335 | } |
| 336 | |
| 337 | void sig_chld(int x) |
| 338 | { |
| 339 | dprint_in_signal = 1; |
| 340 | dprintf2("[%d] SIGCHLD: %d\n", getpid(), x); |
| 341 | dprint_in_signal = 0; |
| 342 | } |
| 343 | |
| 344 | void setup_sigsegv_handler(void) |
| 345 | { |
| 346 | int r, rs; |
| 347 | struct sigaction newact; |
| 348 | struct sigaction oldact; |
| 349 | |
| 350 | /* #PF is mapped to sigsegv */ |
| 351 | int signum = SIGSEGV; |
| 352 | |
| 353 | newact.sa_handler = 0; |
| 354 | newact.sa_sigaction = signal_handler; |
| 355 | |
| 356 | /*sigset_t - signals to block while in the handler */ |
| 357 | /* get the old signal mask. */ |
| 358 | rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask); |
| 359 | pkey_assert(rs == 0); |
| 360 | |
| 361 | /* call sa_sigaction, not sa_handler*/ |
| 362 | newact.sa_flags = SA_SIGINFO; |
| 363 | |
| 364 | newact.sa_restorer = 0; /* void(*)(), obsolete */ |
| 365 | r = sigaction(signum, &newact, &oldact); |
| 366 | r = sigaction(SIGALRM, &newact, &oldact); |
| 367 | pkey_assert(r == 0); |
| 368 | } |
| 369 | |
| 370 | void setup_handlers(void) |
| 371 | { |
| 372 | signal(SIGCHLD, &sig_chld); |
| 373 | setup_sigsegv_handler(); |
| 374 | } |
| 375 | |
| 376 | pid_t fork_lazy_child(void) |
| 377 | { |
| 378 | pid_t forkret; |
| 379 | |
| 380 | forkret = fork(); |
| 381 | pkey_assert(forkret >= 0); |
| 382 | dprintf3("[%d] fork() ret: %d\n", getpid(), forkret); |
| 383 | |
| 384 | if (!forkret) { |
| 385 | /* in the child */ |
| 386 | while (1) { |
| 387 | dprintf1("child sleeping...\n"); |
| 388 | sleep(30); |
| 389 | } |
| 390 | } |
| 391 | return forkret; |
| 392 | } |
| 393 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 394 | #ifndef PKEY_DISABLE_ACCESS |
| 395 | # define PKEY_DISABLE_ACCESS 0x1 |
| 396 | #endif |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 397 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 398 | #ifndef PKEY_DISABLE_WRITE |
| 399 | # define PKEY_DISABLE_WRITE 0x2 |
| 400 | #endif |
| 401 | |
| 402 | static u32 hw_pkey_get(int pkey, unsigned long flags) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 403 | { |
| 404 | u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE); |
| 405 | u32 pkru = __rdpkru(); |
| 406 | u32 shifted_pkru; |
| 407 | u32 masked_pkru; |
| 408 | |
| 409 | dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n", |
| 410 | __func__, pkey, flags, 0, 0); |
| 411 | dprintf2("%s() raw pkru: %x\n", __func__, pkru); |
| 412 | |
| 413 | shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY)); |
| 414 | dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru); |
| 415 | masked_pkru = shifted_pkru & mask; |
| 416 | dprintf2("%s() masked pkru: %x\n", __func__, masked_pkru); |
| 417 | /* |
| 418 | * shift down the relevant bits to the lowest two, then |
| 419 | * mask off all the other high bits. |
| 420 | */ |
| 421 | return masked_pkru; |
| 422 | } |
| 423 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 424 | static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 425 | { |
| 426 | u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE); |
| 427 | u32 old_pkru = __rdpkru(); |
| 428 | u32 new_pkru; |
| 429 | |
| 430 | /* make sure that 'rights' only contains the bits we expect: */ |
| 431 | assert(!(rights & ~mask)); |
| 432 | |
| 433 | /* copy old pkru */ |
| 434 | new_pkru = old_pkru; |
| 435 | /* mask out bits from pkey in old value: */ |
| 436 | new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY)); |
| 437 | /* OR in new bits for pkey: */ |
| 438 | new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY)); |
| 439 | |
| 440 | __wrpkru(new_pkru); |
| 441 | |
| 442 | dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n", |
| 443 | __func__, pkey, rights, flags, 0, __rdpkru(), old_pkru); |
| 444 | return 0; |
| 445 | } |
| 446 | |
| 447 | void pkey_disable_set(int pkey, int flags) |
| 448 | { |
| 449 | unsigned long syscall_flags = 0; |
| 450 | int ret; |
| 451 | int pkey_rights; |
Dave Hansen | 16846c2 | 2017-02-03 10:51:34 -0800 | [diff] [blame] | 452 | u32 orig_pkru = rdpkru(); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 453 | |
| 454 | dprintf1("START->%s(%d, 0x%x)\n", __func__, |
| 455 | pkey, flags); |
| 456 | pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)); |
| 457 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 458 | pkey_rights = hw_pkey_get(pkey, syscall_flags); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 459 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 460 | dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 461 | pkey, pkey, pkey_rights); |
| 462 | pkey_assert(pkey_rights >= 0); |
| 463 | |
| 464 | pkey_rights |= flags; |
| 465 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 466 | ret = hw_pkey_set(pkey, pkey_rights, syscall_flags); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 467 | assert(!ret); |
| 468 | /*pkru and flags have the same format */ |
| 469 | shadow_pkru |= flags << (pkey * 2); |
| 470 | dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru); |
| 471 | |
| 472 | pkey_assert(ret >= 0); |
| 473 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 474 | pkey_rights = hw_pkey_get(pkey, syscall_flags); |
| 475 | dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 476 | pkey, pkey, pkey_rights); |
| 477 | |
| 478 | dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru()); |
| 479 | if (flags) |
| 480 | pkey_assert(rdpkru() > orig_pkru); |
| 481 | dprintf1("END<---%s(%d, 0x%x)\n", __func__, |
| 482 | pkey, flags); |
| 483 | } |
| 484 | |
| 485 | void pkey_disable_clear(int pkey, int flags) |
| 486 | { |
| 487 | unsigned long syscall_flags = 0; |
| 488 | int ret; |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 489 | int pkey_rights = hw_pkey_get(pkey, syscall_flags); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 490 | u32 orig_pkru = rdpkru(); |
| 491 | |
| 492 | pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)); |
| 493 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 494 | dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 495 | pkey, pkey, pkey_rights); |
| 496 | pkey_assert(pkey_rights >= 0); |
| 497 | |
| 498 | pkey_rights |= flags; |
| 499 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 500 | ret = hw_pkey_set(pkey, pkey_rights, 0); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 501 | /* pkru and flags have the same format */ |
| 502 | shadow_pkru &= ~(flags << (pkey * 2)); |
| 503 | pkey_assert(ret >= 0); |
| 504 | |
Ingo Molnar | 0fb9662 | 2018-05-14 10:56:23 +0200 | [diff] [blame] | 505 | pkey_rights = hw_pkey_get(pkey, syscall_flags); |
| 506 | dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__, |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 507 | pkey, pkey, pkey_rights); |
| 508 | |
| 509 | dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru()); |
| 510 | if (flags) |
| 511 | assert(rdpkru() > orig_pkru); |
| 512 | } |
| 513 | |
| 514 | void pkey_write_allow(int pkey) |
| 515 | { |
| 516 | pkey_disable_clear(pkey, PKEY_DISABLE_WRITE); |
| 517 | } |
| 518 | void pkey_write_deny(int pkey) |
| 519 | { |
| 520 | pkey_disable_set(pkey, PKEY_DISABLE_WRITE); |
| 521 | } |
| 522 | void pkey_access_allow(int pkey) |
| 523 | { |
| 524 | pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS); |
| 525 | } |
| 526 | void pkey_access_deny(int pkey) |
| 527 | { |
| 528 | pkey_disable_set(pkey, PKEY_DISABLE_ACCESS); |
| 529 | } |
| 530 | |
| 531 | int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot, |
| 532 | unsigned long pkey) |
| 533 | { |
| 534 | int sret; |
| 535 | |
| 536 | dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__, |
| 537 | ptr, size, orig_prot, pkey); |
| 538 | |
| 539 | errno = 0; |
| 540 | sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey); |
| 541 | if (errno) { |
| 542 | dprintf2("SYS_mprotect_key sret: %d\n", sret); |
| 543 | dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot); |
| 544 | dprintf2("SYS_mprotect_key failed, errno: %d\n", errno); |
| 545 | if (DEBUG_LEVEL >= 2) |
| 546 | perror("SYS_mprotect_pkey"); |
| 547 | } |
| 548 | return sret; |
| 549 | } |
| 550 | |
| 551 | int sys_pkey_alloc(unsigned long flags, unsigned long init_val) |
| 552 | { |
| 553 | int ret = syscall(SYS_pkey_alloc, flags, init_val); |
| 554 | dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n", |
| 555 | __func__, flags, init_val, ret, errno); |
| 556 | return ret; |
| 557 | } |
| 558 | |
| 559 | int alloc_pkey(void) |
| 560 | { |
| 561 | int ret; |
| 562 | unsigned long init_val = 0x0; |
| 563 | |
| 564 | dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n", |
| 565 | __LINE__, __rdpkru(), shadow_pkru); |
| 566 | ret = sys_pkey_alloc(0, init_val); |
| 567 | /* |
| 568 | * pkey_alloc() sets PKRU, so we need to reflect it in |
| 569 | * shadow_pkru: |
| 570 | */ |
| 571 | dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", |
| 572 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 573 | if (ret) { |
| 574 | /* clear both the bits: */ |
| 575 | shadow_pkru &= ~(0x3 << (ret * 2)); |
| 576 | dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", |
| 577 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 578 | /* |
| 579 | * move the new state in from init_val |
| 580 | * (remember, we cheated and init_val == pkru format) |
| 581 | */ |
| 582 | shadow_pkru |= (init_val << (ret * 2)); |
| 583 | } |
| 584 | dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", |
| 585 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 586 | dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno); |
| 587 | /* for shadow checking: */ |
| 588 | rdpkru(); |
| 589 | dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", |
| 590 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 591 | return ret; |
| 592 | } |
| 593 | |
| 594 | int sys_pkey_free(unsigned long pkey) |
| 595 | { |
| 596 | int ret = syscall(SYS_pkey_free, pkey); |
| 597 | dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret); |
| 598 | return ret; |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * I had a bug where pkey bits could be set by mprotect() but |
| 603 | * not cleared. This ensures we get lots of random bit sets |
| 604 | * and clears on the vma and pte pkey bits. |
| 605 | */ |
| 606 | int alloc_random_pkey(void) |
| 607 | { |
| 608 | int max_nr_pkey_allocs; |
| 609 | int ret; |
| 610 | int i; |
| 611 | int alloced_pkeys[NR_PKEYS]; |
| 612 | int nr_alloced = 0; |
| 613 | int random_index; |
| 614 | memset(alloced_pkeys, 0, sizeof(alloced_pkeys)); |
| 615 | |
| 616 | /* allocate every possible key and make a note of which ones we got */ |
| 617 | max_nr_pkey_allocs = NR_PKEYS; |
| 618 | max_nr_pkey_allocs = 1; |
| 619 | for (i = 0; i < max_nr_pkey_allocs; i++) { |
| 620 | int new_pkey = alloc_pkey(); |
| 621 | if (new_pkey < 0) |
| 622 | break; |
| 623 | alloced_pkeys[nr_alloced++] = new_pkey; |
| 624 | } |
| 625 | |
| 626 | pkey_assert(nr_alloced > 0); |
| 627 | /* select a random one out of the allocated ones */ |
| 628 | random_index = rand() % nr_alloced; |
| 629 | ret = alloced_pkeys[random_index]; |
| 630 | /* now zero it out so we don't free it next */ |
| 631 | alloced_pkeys[random_index] = 0; |
| 632 | |
| 633 | /* go through the allocated ones that we did not want and free them */ |
| 634 | for (i = 0; i < nr_alloced; i++) { |
| 635 | int free_ret; |
| 636 | if (!alloced_pkeys[i]) |
| 637 | continue; |
| 638 | free_ret = sys_pkey_free(alloced_pkeys[i]); |
| 639 | pkey_assert(!free_ret); |
| 640 | } |
| 641 | dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__, |
| 642 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 643 | return ret; |
| 644 | } |
| 645 | |
| 646 | int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot, |
| 647 | unsigned long pkey) |
| 648 | { |
| 649 | int nr_iterations = random() % 100; |
| 650 | int ret; |
| 651 | |
| 652 | while (0) { |
| 653 | int rpkey = alloc_random_pkey(); |
| 654 | ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey); |
| 655 | dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n", |
| 656 | ptr, size, orig_prot, pkey, ret); |
| 657 | if (nr_iterations-- < 0) |
| 658 | break; |
| 659 | |
| 660 | dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__, |
| 661 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 662 | sys_pkey_free(rpkey); |
| 663 | dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__, |
| 664 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 665 | } |
| 666 | pkey_assert(pkey < NR_PKEYS); |
| 667 | |
| 668 | ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey); |
| 669 | dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n", |
| 670 | ptr, size, orig_prot, pkey, ret); |
| 671 | pkey_assert(!ret); |
| 672 | dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__, |
| 673 | __LINE__, ret, __rdpkru(), shadow_pkru); |
| 674 | return ret; |
| 675 | } |
| 676 | |
| 677 | struct pkey_malloc_record { |
| 678 | void *ptr; |
| 679 | long size; |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 680 | int prot; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 681 | }; |
| 682 | struct pkey_malloc_record *pkey_malloc_records; |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 683 | struct pkey_malloc_record *pkey_last_malloc_record; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 684 | long nr_pkey_malloc_records; |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 685 | void record_pkey_malloc(void *ptr, long size, int prot) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 686 | { |
| 687 | long i; |
| 688 | struct pkey_malloc_record *rec = NULL; |
| 689 | |
| 690 | for (i = 0; i < nr_pkey_malloc_records; i++) { |
| 691 | rec = &pkey_malloc_records[i]; |
| 692 | /* find a free record */ |
| 693 | if (rec) |
| 694 | break; |
| 695 | } |
| 696 | if (!rec) { |
| 697 | /* every record is full */ |
| 698 | size_t old_nr_records = nr_pkey_malloc_records; |
| 699 | size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1); |
| 700 | size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record); |
| 701 | dprintf2("new_nr_records: %zd\n", new_nr_records); |
| 702 | dprintf2("new_size: %zd\n", new_size); |
| 703 | pkey_malloc_records = realloc(pkey_malloc_records, new_size); |
| 704 | pkey_assert(pkey_malloc_records != NULL); |
| 705 | rec = &pkey_malloc_records[nr_pkey_malloc_records]; |
| 706 | /* |
| 707 | * realloc() does not initialize memory, so zero it from |
| 708 | * the first new record all the way to the end. |
| 709 | */ |
| 710 | for (i = 0; i < new_nr_records - old_nr_records; i++) |
| 711 | memset(rec + i, 0, sizeof(*rec)); |
| 712 | } |
| 713 | dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n", |
| 714 | (int)(rec - pkey_malloc_records), rec, ptr, size); |
| 715 | rec->ptr = ptr; |
| 716 | rec->size = size; |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 717 | rec->prot = prot; |
| 718 | pkey_last_malloc_record = rec; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 719 | nr_pkey_malloc_records++; |
| 720 | } |
| 721 | |
| 722 | void free_pkey_malloc(void *ptr) |
| 723 | { |
| 724 | long i; |
| 725 | int ret; |
| 726 | dprintf3("%s(%p)\n", __func__, ptr); |
| 727 | for (i = 0; i < nr_pkey_malloc_records; i++) { |
| 728 | struct pkey_malloc_record *rec = &pkey_malloc_records[i]; |
| 729 | dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n", |
| 730 | ptr, i, rec, rec->ptr, rec->size); |
| 731 | if ((ptr < rec->ptr) || |
| 732 | (ptr >= rec->ptr + rec->size)) |
| 733 | continue; |
| 734 | |
| 735 | dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n", |
| 736 | ptr, i, rec, rec->ptr, rec->size); |
| 737 | nr_pkey_malloc_records--; |
| 738 | ret = munmap(rec->ptr, rec->size); |
| 739 | dprintf3("munmap ret: %d\n", ret); |
| 740 | pkey_assert(!ret); |
| 741 | dprintf3("clearing rec->ptr, rec: %p\n", rec); |
| 742 | rec->ptr = NULL; |
| 743 | dprintf3("done clearing rec->ptr, rec: %p\n", rec); |
| 744 | return; |
| 745 | } |
| 746 | pkey_assert(false); |
| 747 | } |
| 748 | |
| 749 | |
| 750 | void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey) |
| 751 | { |
| 752 | void *ptr; |
| 753 | int ret; |
| 754 | |
| 755 | rdpkru(); |
| 756 | dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__, |
| 757 | size, prot, pkey); |
| 758 | pkey_assert(pkey < NR_PKEYS); |
| 759 | ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); |
| 760 | pkey_assert(ptr != (void *)-1); |
| 761 | ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey); |
| 762 | pkey_assert(!ret); |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 763 | record_pkey_malloc(ptr, size, prot); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 764 | rdpkru(); |
| 765 | |
| 766 | dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr); |
| 767 | return ptr; |
| 768 | } |
| 769 | |
| 770 | void *malloc_pkey_anon_huge(long size, int prot, u16 pkey) |
| 771 | { |
| 772 | int ret; |
| 773 | void *ptr; |
| 774 | |
| 775 | dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__, |
| 776 | size, prot, pkey); |
| 777 | /* |
| 778 | * Guarantee we can fit at least one huge page in the resulting |
| 779 | * allocation by allocating space for 2: |
| 780 | */ |
| 781 | size = ALIGN_UP(size, HPAGE_SIZE * 2); |
| 782 | ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); |
| 783 | pkey_assert(ptr != (void *)-1); |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 784 | record_pkey_malloc(ptr, size, prot); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 785 | mprotect_pkey(ptr, size, prot, pkey); |
| 786 | |
| 787 | dprintf1("unaligned ptr: %p\n", ptr); |
| 788 | ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE); |
| 789 | dprintf1(" aligned ptr: %p\n", ptr); |
| 790 | ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE); |
| 791 | dprintf1("MADV_HUGEPAGE ret: %d\n", ret); |
| 792 | ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED); |
| 793 | dprintf1("MADV_WILLNEED ret: %d\n", ret); |
| 794 | memset(ptr, 0, HPAGE_SIZE); |
| 795 | |
| 796 | dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr); |
| 797 | return ptr; |
| 798 | } |
| 799 | |
| 800 | int hugetlb_setup_ok; |
| 801 | #define GET_NR_HUGE_PAGES 10 |
| 802 | void setup_hugetlbfs(void) |
| 803 | { |
| 804 | int err; |
| 805 | int fd; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 806 | char buf[] = "123"; |
| 807 | |
| 808 | if (geteuid() != 0) { |
| 809 | fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n"); |
| 810 | return; |
| 811 | } |
| 812 | |
| 813 | cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages"); |
| 814 | |
| 815 | /* |
| 816 | * Now go make sure that we got the pages and that they |
| 817 | * are 2M pages. Someone might have made 1G the default. |
| 818 | */ |
| 819 | fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY); |
| 820 | if (fd < 0) { |
| 821 | perror("opening sysfs 2M hugetlb config"); |
| 822 | return; |
| 823 | } |
| 824 | |
| 825 | /* -1 to guarantee leaving the trailing \0 */ |
| 826 | err = read(fd, buf, sizeof(buf)-1); |
| 827 | close(fd); |
| 828 | if (err <= 0) { |
| 829 | perror("reading sysfs 2M hugetlb config"); |
| 830 | return; |
| 831 | } |
| 832 | |
| 833 | if (atoi(buf) != GET_NR_HUGE_PAGES) { |
| 834 | fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n", |
| 835 | buf, GET_NR_HUGE_PAGES); |
| 836 | return; |
| 837 | } |
| 838 | |
| 839 | hugetlb_setup_ok = 1; |
| 840 | } |
| 841 | |
| 842 | void *malloc_pkey_hugetlb(long size, int prot, u16 pkey) |
| 843 | { |
| 844 | void *ptr; |
| 845 | int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB; |
| 846 | |
| 847 | if (!hugetlb_setup_ok) |
| 848 | return PTR_ERR_ENOTSUP; |
| 849 | |
| 850 | dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey); |
| 851 | size = ALIGN_UP(size, HPAGE_SIZE * 2); |
| 852 | pkey_assert(pkey < NR_PKEYS); |
| 853 | ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0); |
| 854 | pkey_assert(ptr != (void *)-1); |
| 855 | mprotect_pkey(ptr, size, prot, pkey); |
| 856 | |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 857 | record_pkey_malloc(ptr, size, prot); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 858 | |
| 859 | dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr); |
| 860 | return ptr; |
| 861 | } |
| 862 | |
| 863 | void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey) |
| 864 | { |
| 865 | void *ptr; |
| 866 | int fd; |
| 867 | |
| 868 | dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__, |
| 869 | size, prot, pkey); |
| 870 | pkey_assert(pkey < NR_PKEYS); |
| 871 | fd = open("/dax/foo", O_RDWR); |
| 872 | pkey_assert(fd >= 0); |
| 873 | |
| 874 | ptr = mmap(0, size, prot, MAP_SHARED, fd, 0); |
| 875 | pkey_assert(ptr != (void *)-1); |
| 876 | |
| 877 | mprotect_pkey(ptr, size, prot, pkey); |
| 878 | |
Dave Hansen | acb25d7 | 2018-05-09 10:13:54 -0700 | [diff] [blame] | 879 | record_pkey_malloc(ptr, size, prot); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 880 | |
| 881 | dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr); |
| 882 | close(fd); |
| 883 | return ptr; |
| 884 | } |
| 885 | |
| 886 | void *(*pkey_malloc[])(long size, int prot, u16 pkey) = { |
| 887 | |
| 888 | malloc_pkey_with_mprotect, |
| 889 | malloc_pkey_anon_huge, |
| 890 | malloc_pkey_hugetlb |
| 891 | /* can not do direct with the pkey_mprotect() API: |
| 892 | malloc_pkey_mmap_direct, |
| 893 | malloc_pkey_mmap_dax, |
| 894 | */ |
| 895 | }; |
| 896 | |
| 897 | void *malloc_pkey(long size, int prot, u16 pkey) |
| 898 | { |
| 899 | void *ret; |
| 900 | static int malloc_type; |
| 901 | int nr_malloc_types = ARRAY_SIZE(pkey_malloc); |
| 902 | |
| 903 | pkey_assert(pkey < NR_PKEYS); |
| 904 | |
| 905 | while (1) { |
| 906 | pkey_assert(malloc_type < nr_malloc_types); |
| 907 | |
| 908 | ret = pkey_malloc[malloc_type](size, prot, pkey); |
| 909 | pkey_assert(ret != (void *)-1); |
| 910 | |
| 911 | malloc_type++; |
| 912 | if (malloc_type >= nr_malloc_types) |
| 913 | malloc_type = (random()%nr_malloc_types); |
| 914 | |
| 915 | /* try again if the malloc_type we tried is unsupported */ |
| 916 | if (ret == PTR_ERR_ENOTSUP) |
| 917 | continue; |
| 918 | |
| 919 | break; |
| 920 | } |
| 921 | |
| 922 | dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__, |
| 923 | size, prot, pkey, ret); |
| 924 | return ret; |
| 925 | } |
| 926 | |
| 927 | int last_pkru_faults; |
Dave Hansen | 7e7fd67 | 2018-05-09 10:13:46 -0700 | [diff] [blame] | 928 | #define UNKNOWN_PKEY -2 |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 929 | void expected_pk_fault(int pkey) |
| 930 | { |
| 931 | dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n", |
| 932 | __func__, last_pkru_faults, pkru_faults); |
| 933 | dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey); |
| 934 | pkey_assert(last_pkru_faults + 1 == pkru_faults); |
Dave Hansen | 7e7fd67 | 2018-05-09 10:13:46 -0700 | [diff] [blame] | 935 | |
| 936 | /* |
| 937 | * For exec-only memory, we do not know the pkey in |
| 938 | * advance, so skip this check. |
| 939 | */ |
| 940 | if (pkey != UNKNOWN_PKEY) |
| 941 | pkey_assert(last_si_pkey == pkey); |
| 942 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 943 | /* |
| 944 | * The signal handler shold have cleared out PKRU to let the |
| 945 | * test program continue. We now have to restore it. |
| 946 | */ |
| 947 | if (__rdpkru() != 0) |
| 948 | pkey_assert(0); |
| 949 | |
| 950 | __wrpkru(shadow_pkru); |
| 951 | dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n", |
| 952 | __func__, shadow_pkru); |
| 953 | last_pkru_faults = pkru_faults; |
| 954 | last_si_pkey = -1; |
| 955 | } |
| 956 | |
Dave Hansen | 55556b0 | 2018-05-09 10:13:38 -0700 | [diff] [blame] | 957 | #define do_not_expect_pk_fault(msg) do { \ |
| 958 | if (last_pkru_faults != pkru_faults) \ |
| 959 | dprintf0("unexpected PK fault: %s\n", msg); \ |
| 960 | pkey_assert(last_pkru_faults == pkru_faults); \ |
| 961 | } while (0) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 962 | |
| 963 | int test_fds[10] = { -1 }; |
| 964 | int nr_test_fds; |
| 965 | void __save_test_fd(int fd) |
| 966 | { |
| 967 | pkey_assert(fd >= 0); |
| 968 | pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds)); |
| 969 | test_fds[nr_test_fds] = fd; |
| 970 | nr_test_fds++; |
| 971 | } |
| 972 | |
| 973 | int get_test_read_fd(void) |
| 974 | { |
| 975 | int test_fd = open("/etc/passwd", O_RDONLY); |
| 976 | __save_test_fd(test_fd); |
| 977 | return test_fd; |
| 978 | } |
| 979 | |
| 980 | void close_test_fds(void) |
| 981 | { |
| 982 | int i; |
| 983 | |
| 984 | for (i = 0; i < nr_test_fds; i++) { |
| 985 | if (test_fds[i] < 0) |
| 986 | continue; |
| 987 | close(test_fds[i]); |
| 988 | test_fds[i] = -1; |
| 989 | } |
| 990 | nr_test_fds = 0; |
| 991 | } |
| 992 | |
| 993 | #define barrier() __asm__ __volatile__("": : :"memory") |
| 994 | __attribute__((noinline)) int read_ptr(int *ptr) |
| 995 | { |
| 996 | /* |
| 997 | * Keep GCC from optimizing this away somehow |
| 998 | */ |
| 999 | barrier(); |
| 1000 | return *ptr; |
| 1001 | } |
| 1002 | |
| 1003 | void test_read_of_write_disabled_region(int *ptr, u16 pkey) |
| 1004 | { |
| 1005 | int ptr_contents; |
| 1006 | |
| 1007 | dprintf1("disabling write access to PKEY[1], doing read\n"); |
| 1008 | pkey_write_deny(pkey); |
| 1009 | ptr_contents = read_ptr(ptr); |
| 1010 | dprintf1("*ptr: %d\n", ptr_contents); |
| 1011 | dprintf1("\n"); |
| 1012 | } |
| 1013 | void test_read_of_access_disabled_region(int *ptr, u16 pkey) |
| 1014 | { |
| 1015 | int ptr_contents; |
| 1016 | |
| 1017 | dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr); |
| 1018 | rdpkru(); |
| 1019 | pkey_access_deny(pkey); |
| 1020 | ptr_contents = read_ptr(ptr); |
| 1021 | dprintf1("*ptr: %d\n", ptr_contents); |
| 1022 | expected_pk_fault(pkey); |
| 1023 | } |
| 1024 | void test_write_of_write_disabled_region(int *ptr, u16 pkey) |
| 1025 | { |
| 1026 | dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey); |
| 1027 | pkey_write_deny(pkey); |
| 1028 | *ptr = __LINE__; |
| 1029 | expected_pk_fault(pkey); |
| 1030 | } |
| 1031 | void test_write_of_access_disabled_region(int *ptr, u16 pkey) |
| 1032 | { |
| 1033 | dprintf1("disabling access to PKEY[%02d], doing write\n", pkey); |
| 1034 | pkey_access_deny(pkey); |
| 1035 | *ptr = __LINE__; |
| 1036 | expected_pk_fault(pkey); |
| 1037 | } |
| 1038 | void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey) |
| 1039 | { |
| 1040 | int ret; |
| 1041 | int test_fd = get_test_read_fd(); |
| 1042 | |
| 1043 | dprintf1("disabling access to PKEY[%02d], " |
| 1044 | "having kernel read() to buffer\n", pkey); |
| 1045 | pkey_access_deny(pkey); |
| 1046 | ret = read(test_fd, ptr, 1); |
| 1047 | dprintf1("read ret: %d\n", ret); |
| 1048 | pkey_assert(ret); |
| 1049 | } |
| 1050 | void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey) |
| 1051 | { |
| 1052 | int ret; |
| 1053 | int test_fd = get_test_read_fd(); |
| 1054 | |
| 1055 | pkey_write_deny(pkey); |
| 1056 | ret = read(test_fd, ptr, 100); |
| 1057 | dprintf1("read ret: %d\n", ret); |
| 1058 | if (ret < 0 && (DEBUG_LEVEL > 0)) |
| 1059 | perror("verbose read result (OK for this to be bad)"); |
| 1060 | pkey_assert(ret); |
| 1061 | } |
| 1062 | |
| 1063 | void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey) |
| 1064 | { |
| 1065 | int pipe_ret, vmsplice_ret; |
| 1066 | struct iovec iov; |
| 1067 | int pipe_fds[2]; |
| 1068 | |
| 1069 | pipe_ret = pipe(pipe_fds); |
| 1070 | |
| 1071 | pkey_assert(pipe_ret == 0); |
| 1072 | dprintf1("disabling access to PKEY[%02d], " |
| 1073 | "having kernel vmsplice from buffer\n", pkey); |
| 1074 | pkey_access_deny(pkey); |
| 1075 | iov.iov_base = ptr; |
| 1076 | iov.iov_len = PAGE_SIZE; |
| 1077 | vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT); |
| 1078 | dprintf1("vmsplice() ret: %d\n", vmsplice_ret); |
| 1079 | pkey_assert(vmsplice_ret == -1); |
| 1080 | |
| 1081 | close(pipe_fds[0]); |
| 1082 | close(pipe_fds[1]); |
| 1083 | } |
| 1084 | |
| 1085 | void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey) |
| 1086 | { |
| 1087 | int ignored = 0xdada; |
| 1088 | int futex_ret; |
| 1089 | int some_int = __LINE__; |
| 1090 | |
| 1091 | dprintf1("disabling write to PKEY[%02d], " |
| 1092 | "doing futex gunk in buffer\n", pkey); |
| 1093 | *ptr = some_int; |
| 1094 | pkey_write_deny(pkey); |
| 1095 | futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL, |
| 1096 | &ignored, ignored); |
| 1097 | if (DEBUG_LEVEL > 0) |
| 1098 | perror("futex"); |
| 1099 | dprintf1("futex() ret: %d\n", futex_ret); |
| 1100 | } |
| 1101 | |
| 1102 | /* Assumes that all pkeys other than 'pkey' are unallocated */ |
| 1103 | void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey) |
| 1104 | { |
| 1105 | int err; |
| 1106 | int i; |
| 1107 | |
| 1108 | /* Note: 0 is the default pkey, so don't mess with it */ |
| 1109 | for (i = 1; i < NR_PKEYS; i++) { |
| 1110 | if (pkey == i) |
| 1111 | continue; |
| 1112 | |
| 1113 | dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i); |
| 1114 | err = sys_pkey_free(i); |
| 1115 | pkey_assert(err); |
| 1116 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1117 | err = sys_pkey_free(i); |
| 1118 | pkey_assert(err); |
| 1119 | |
| 1120 | err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i); |
| 1121 | pkey_assert(err); |
| 1122 | } |
| 1123 | } |
| 1124 | |
| 1125 | /* Assumes that all pkeys other than 'pkey' are unallocated */ |
| 1126 | void test_pkey_syscalls_bad_args(int *ptr, u16 pkey) |
| 1127 | { |
| 1128 | int err; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1129 | int bad_pkey = NR_PKEYS+99; |
| 1130 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1131 | /* pass a known-invalid pkey in: */ |
| 1132 | err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey); |
| 1133 | pkey_assert(err); |
| 1134 | } |
| 1135 | |
| 1136 | /* Assumes that all pkeys other than 'pkey' are unallocated */ |
| 1137 | void test_pkey_alloc_exhaust(int *ptr, u16 pkey) |
| 1138 | { |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1139 | int err; |
| 1140 | int allocated_pkeys[NR_PKEYS] = {0}; |
| 1141 | int nr_allocated_pkeys = 0; |
| 1142 | int i; |
| 1143 | |
| 1144 | for (i = 0; i < NR_PKEYS*2; i++) { |
| 1145 | int new_pkey; |
| 1146 | dprintf1("%s() alloc loop: %d\n", __func__, i); |
| 1147 | new_pkey = alloc_pkey(); |
| 1148 | dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__, |
| 1149 | __LINE__, err, __rdpkru(), shadow_pkru); |
| 1150 | rdpkru(); /* for shadow checking */ |
| 1151 | dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC); |
| 1152 | if ((new_pkey == -1) && (errno == ENOSPC)) { |
| 1153 | dprintf2("%s() failed to allocate pkey after %d tries\n", |
| 1154 | __func__, nr_allocated_pkeys); |
| 1155 | break; |
| 1156 | } |
| 1157 | pkey_assert(nr_allocated_pkeys < NR_PKEYS); |
| 1158 | allocated_pkeys[nr_allocated_pkeys++] = new_pkey; |
| 1159 | } |
| 1160 | |
| 1161 | dprintf3("%s()::%d\n", __func__, __LINE__); |
| 1162 | |
| 1163 | /* |
| 1164 | * ensure it did not reach the end of the loop without |
| 1165 | * failure: |
| 1166 | */ |
| 1167 | pkey_assert(i < NR_PKEYS*2); |
| 1168 | |
| 1169 | /* |
Dave Hansen | f50b487 | 2018-05-09 10:13:50 -0700 | [diff] [blame] | 1170 | * There are 16 pkeys supported in hardware. Three are |
| 1171 | * allocated by the time we get here: |
| 1172 | * 1. The default key (0) |
| 1173 | * 2. One possibly consumed by an execute-only mapping. |
| 1174 | * 3. One allocated by the test code and passed in via |
| 1175 | * 'pkey' to this function. |
| 1176 | * Ensure that we can allocate at least another 13 (16-3). |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1177 | */ |
Dave Hansen | f50b487 | 2018-05-09 10:13:50 -0700 | [diff] [blame] | 1178 | pkey_assert(i >= NR_PKEYS-3); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1179 | |
| 1180 | for (i = 0; i < nr_allocated_pkeys; i++) { |
| 1181 | err = sys_pkey_free(allocated_pkeys[i]); |
| 1182 | pkey_assert(!err); |
| 1183 | rdpkru(); /* for shadow checking */ |
| 1184 | } |
| 1185 | } |
| 1186 | |
Dave Hansen | 3488a60 | 2018-05-09 10:13:56 -0700 | [diff] [blame] | 1187 | /* |
| 1188 | * pkey 0 is special. It is allocated by default, so you do not |
| 1189 | * have to call pkey_alloc() to use it first. Make sure that it |
| 1190 | * is usable. |
| 1191 | */ |
| 1192 | void test_mprotect_with_pkey_0(int *ptr, u16 pkey) |
| 1193 | { |
| 1194 | long size; |
| 1195 | int prot; |
| 1196 | |
| 1197 | assert(pkey_last_malloc_record); |
| 1198 | size = pkey_last_malloc_record->size; |
| 1199 | /* |
| 1200 | * This is a bit of a hack. But mprotect() requires |
| 1201 | * huge-page-aligned sizes when operating on hugetlbfs. |
| 1202 | * So, make sure that we use something that's a multiple |
| 1203 | * of a huge page when we can. |
| 1204 | */ |
| 1205 | if (size >= HPAGE_SIZE) |
| 1206 | size = HPAGE_SIZE; |
| 1207 | prot = pkey_last_malloc_record->prot; |
| 1208 | |
| 1209 | /* Use pkey 0 */ |
| 1210 | mprotect_pkey(ptr, size, prot, 0); |
| 1211 | |
| 1212 | /* Make sure that we can set it back to the original pkey. */ |
| 1213 | mprotect_pkey(ptr, size, prot, pkey); |
| 1214 | } |
| 1215 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1216 | void test_ptrace_of_child(int *ptr, u16 pkey) |
| 1217 | { |
| 1218 | __attribute__((__unused__)) int peek_result; |
| 1219 | pid_t child_pid; |
| 1220 | void *ignored = 0; |
| 1221 | long ret; |
| 1222 | int status; |
| 1223 | /* |
| 1224 | * This is the "control" for our little expermient. Make sure |
| 1225 | * we can always access it when ptracing. |
| 1226 | */ |
| 1227 | int *plain_ptr_unaligned = malloc(HPAGE_SIZE); |
| 1228 | int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE); |
| 1229 | |
| 1230 | /* |
| 1231 | * Fork a child which is an exact copy of this process, of course. |
| 1232 | * That means we can do all of our tests via ptrace() and then plain |
| 1233 | * memory access and ensure they work differently. |
| 1234 | */ |
| 1235 | child_pid = fork_lazy_child(); |
| 1236 | dprintf1("[%d] child pid: %d\n", getpid(), child_pid); |
| 1237 | |
| 1238 | ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored); |
| 1239 | if (ret) |
| 1240 | perror("attach"); |
| 1241 | dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__); |
| 1242 | pkey_assert(ret != -1); |
| 1243 | ret = waitpid(child_pid, &status, WUNTRACED); |
| 1244 | if ((ret != child_pid) || !(WIFSTOPPED(status))) { |
| 1245 | fprintf(stderr, "weird waitpid result %ld stat %x\n", |
| 1246 | ret, status); |
| 1247 | pkey_assert(0); |
| 1248 | } |
| 1249 | dprintf2("waitpid ret: %ld\n", ret); |
| 1250 | dprintf2("waitpid status: %d\n", status); |
| 1251 | |
| 1252 | pkey_access_deny(pkey); |
| 1253 | pkey_write_deny(pkey); |
| 1254 | |
| 1255 | /* Write access, untested for now: |
| 1256 | ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data); |
| 1257 | pkey_assert(ret != -1); |
| 1258 | dprintf1("poke at %p: %ld\n", peek_at, ret); |
| 1259 | */ |
| 1260 | |
| 1261 | /* |
| 1262 | * Try to access the pkey-protected "ptr" via ptrace: |
| 1263 | */ |
| 1264 | ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored); |
| 1265 | /* expect it to work, without an error: */ |
| 1266 | pkey_assert(ret != -1); |
| 1267 | /* Now access from the current task, and expect an exception: */ |
| 1268 | peek_result = read_ptr(ptr); |
| 1269 | expected_pk_fault(pkey); |
| 1270 | |
| 1271 | /* |
| 1272 | * Try to access the NON-pkey-protected "plain_ptr" via ptrace: |
| 1273 | */ |
| 1274 | ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored); |
| 1275 | /* expect it to work, without an error: */ |
| 1276 | pkey_assert(ret != -1); |
| 1277 | /* Now access from the current task, and expect NO exception: */ |
| 1278 | peek_result = read_ptr(plain_ptr); |
Dave Hansen | 55556b0 | 2018-05-09 10:13:38 -0700 | [diff] [blame] | 1279 | do_not_expect_pk_fault("read plain pointer after ptrace"); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1280 | |
| 1281 | ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0); |
| 1282 | pkey_assert(ret != -1); |
| 1283 | |
| 1284 | ret = kill(child_pid, SIGKILL); |
| 1285 | pkey_assert(ret != -1); |
| 1286 | |
| 1287 | wait(&status); |
| 1288 | |
| 1289 | free(plain_ptr_unaligned); |
| 1290 | } |
| 1291 | |
Dave Hansen | 3fcd2b2 | 2018-05-09 10:13:47 -0700 | [diff] [blame] | 1292 | void *get_pointer_to_instructions(void) |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1293 | { |
| 1294 | void *p1; |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1295 | |
| 1296 | p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE); |
| 1297 | dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write); |
| 1298 | /* lots_o_noops_around_write should be page-aligned already */ |
| 1299 | assert(p1 == &lots_o_noops_around_write); |
| 1300 | |
| 1301 | /* Point 'p1' at the *second* page of the function: */ |
| 1302 | p1 += PAGE_SIZE; |
| 1303 | |
Dave Hansen | 3fcd2b2 | 2018-05-09 10:13:47 -0700 | [diff] [blame] | 1304 | /* |
| 1305 | * Try to ensure we fault this in on next touch to ensure |
| 1306 | * we get an instruction fault as opposed to a data one |
| 1307 | */ |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1308 | madvise(p1, PAGE_SIZE, MADV_DONTNEED); |
Dave Hansen | 3fcd2b2 | 2018-05-09 10:13:47 -0700 | [diff] [blame] | 1309 | |
| 1310 | return p1; |
| 1311 | } |
| 1312 | |
| 1313 | void test_executing_on_unreadable_memory(int *ptr, u16 pkey) |
| 1314 | { |
| 1315 | void *p1; |
| 1316 | int scratch; |
| 1317 | int ptr_contents; |
| 1318 | int ret; |
| 1319 | |
| 1320 | p1 = get_pointer_to_instructions(); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1321 | lots_o_noops_around_write(&scratch); |
| 1322 | ptr_contents = read_ptr(p1); |
| 1323 | dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents); |
| 1324 | |
| 1325 | ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey); |
| 1326 | pkey_assert(!ret); |
| 1327 | pkey_access_deny(pkey); |
| 1328 | |
| 1329 | dprintf2("pkru: %x\n", rdpkru()); |
| 1330 | |
| 1331 | /* |
| 1332 | * Make sure this is an *instruction* fault |
| 1333 | */ |
| 1334 | madvise(p1, PAGE_SIZE, MADV_DONTNEED); |
| 1335 | lots_o_noops_around_write(&scratch); |
Dave Hansen | 55556b0 | 2018-05-09 10:13:38 -0700 | [diff] [blame] | 1336 | do_not_expect_pk_fault("executing on PROT_EXEC memory"); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1337 | ptr_contents = read_ptr(p1); |
| 1338 | dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents); |
| 1339 | expected_pk_fault(pkey); |
| 1340 | } |
| 1341 | |
Dave Hansen | 6af17cf | 2018-05-09 10:13:48 -0700 | [diff] [blame] | 1342 | void test_implicit_mprotect_exec_only_memory(int *ptr, u16 pkey) |
| 1343 | { |
| 1344 | void *p1; |
| 1345 | int scratch; |
| 1346 | int ptr_contents; |
| 1347 | int ret; |
| 1348 | |
| 1349 | dprintf1("%s() start\n", __func__); |
| 1350 | |
| 1351 | p1 = get_pointer_to_instructions(); |
| 1352 | lots_o_noops_around_write(&scratch); |
| 1353 | ptr_contents = read_ptr(p1); |
| 1354 | dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents); |
| 1355 | |
| 1356 | /* Use a *normal* mprotect(), not mprotect_pkey(): */ |
| 1357 | ret = mprotect(p1, PAGE_SIZE, PROT_EXEC); |
| 1358 | pkey_assert(!ret); |
| 1359 | |
| 1360 | dprintf2("pkru: %x\n", rdpkru()); |
| 1361 | |
| 1362 | /* Make sure this is an *instruction* fault */ |
| 1363 | madvise(p1, PAGE_SIZE, MADV_DONTNEED); |
| 1364 | lots_o_noops_around_write(&scratch); |
| 1365 | do_not_expect_pk_fault("executing on PROT_EXEC memory"); |
| 1366 | ptr_contents = read_ptr(p1); |
| 1367 | dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents); |
| 1368 | expected_pk_fault(UNKNOWN_PKEY); |
| 1369 | |
| 1370 | /* |
| 1371 | * Put the memory back to non-PROT_EXEC. Should clear the |
| 1372 | * exec-only pkey off the VMA and allow it to be readable |
| 1373 | * again. Go to PROT_NONE first to check for a kernel bug |
| 1374 | * that did not clear the pkey when doing PROT_NONE. |
| 1375 | */ |
| 1376 | ret = mprotect(p1, PAGE_SIZE, PROT_NONE); |
| 1377 | pkey_assert(!ret); |
| 1378 | |
| 1379 | ret = mprotect(p1, PAGE_SIZE, PROT_READ|PROT_EXEC); |
| 1380 | pkey_assert(!ret); |
| 1381 | ptr_contents = read_ptr(p1); |
| 1382 | do_not_expect_pk_fault("plain read on recently PROT_EXEC area"); |
| 1383 | } |
| 1384 | |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1385 | void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey) |
| 1386 | { |
| 1387 | int size = PAGE_SIZE; |
| 1388 | int sret; |
| 1389 | |
| 1390 | if (cpu_has_pku()) { |
| 1391 | dprintf1("SKIP: %s: no CPU support\n", __func__); |
| 1392 | return; |
| 1393 | } |
| 1394 | |
| 1395 | sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey); |
| 1396 | pkey_assert(sret < 0); |
| 1397 | } |
| 1398 | |
| 1399 | void (*pkey_tests[])(int *ptr, u16 pkey) = { |
| 1400 | test_read_of_write_disabled_region, |
| 1401 | test_read_of_access_disabled_region, |
| 1402 | test_write_of_write_disabled_region, |
| 1403 | test_write_of_access_disabled_region, |
| 1404 | test_kernel_write_of_access_disabled_region, |
| 1405 | test_kernel_write_of_write_disabled_region, |
| 1406 | test_kernel_gup_of_access_disabled_region, |
| 1407 | test_kernel_gup_write_to_write_disabled_region, |
| 1408 | test_executing_on_unreadable_memory, |
Dave Hansen | 6af17cf | 2018-05-09 10:13:48 -0700 | [diff] [blame] | 1409 | test_implicit_mprotect_exec_only_memory, |
Dave Hansen | 3488a60 | 2018-05-09 10:13:56 -0700 | [diff] [blame] | 1410 | test_mprotect_with_pkey_0, |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1411 | test_ptrace_of_child, |
| 1412 | test_pkey_syscalls_on_non_allocated_pkey, |
| 1413 | test_pkey_syscalls_bad_args, |
| 1414 | test_pkey_alloc_exhaust, |
| 1415 | }; |
| 1416 | |
| 1417 | void run_tests_once(void) |
| 1418 | { |
| 1419 | int *ptr; |
| 1420 | int prot = PROT_READ|PROT_WRITE; |
| 1421 | |
| 1422 | for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) { |
| 1423 | int pkey; |
| 1424 | int orig_pkru_faults = pkru_faults; |
| 1425 | |
| 1426 | dprintf1("======================\n"); |
| 1427 | dprintf1("test %d preparing...\n", test_nr); |
| 1428 | |
| 1429 | tracing_on(); |
| 1430 | pkey = alloc_random_pkey(); |
| 1431 | dprintf1("test %d starting with pkey: %d\n", test_nr, pkey); |
| 1432 | ptr = malloc_pkey(PAGE_SIZE, prot, pkey); |
| 1433 | dprintf1("test %d starting...\n", test_nr); |
| 1434 | pkey_tests[test_nr](ptr, pkey); |
| 1435 | dprintf1("freeing test memory: %p\n", ptr); |
| 1436 | free_pkey_malloc(ptr); |
| 1437 | sys_pkey_free(pkey); |
| 1438 | |
| 1439 | dprintf1("pkru_faults: %d\n", pkru_faults); |
| 1440 | dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults); |
| 1441 | |
| 1442 | tracing_off(); |
| 1443 | close_test_fds(); |
| 1444 | |
Colin King | 7738789 | 2016-12-27 16:17:21 +0000 | [diff] [blame] | 1445 | printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr); |
Dave Hansen | 5f23f6d | 2016-07-29 09:30:24 -0700 | [diff] [blame] | 1446 | dprintf1("======================\n\n"); |
| 1447 | } |
| 1448 | iteration_nr++; |
| 1449 | } |
| 1450 | |
| 1451 | void pkey_setup_shadow(void) |
| 1452 | { |
| 1453 | shadow_pkru = __rdpkru(); |
| 1454 | } |
| 1455 | |
| 1456 | int main(void) |
| 1457 | { |
| 1458 | int nr_iterations = 22; |
| 1459 | |
| 1460 | setup_handlers(); |
| 1461 | |
| 1462 | printf("has pku: %d\n", cpu_has_pku()); |
| 1463 | |
| 1464 | if (!cpu_has_pku()) { |
| 1465 | int size = PAGE_SIZE; |
| 1466 | int *ptr; |
| 1467 | |
| 1468 | printf("running PKEY tests for unsupported CPU/OS\n"); |
| 1469 | |
| 1470 | ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0); |
| 1471 | assert(ptr != (void *)-1); |
| 1472 | test_mprotect_pkey_on_unsupported_cpu(ptr, 1); |
| 1473 | exit(0); |
| 1474 | } |
| 1475 | |
| 1476 | pkey_setup_shadow(); |
| 1477 | printf("startup pkru: %x\n", rdpkru()); |
| 1478 | setup_hugetlbfs(); |
| 1479 | |
| 1480 | while (nr_iterations-- > 0) |
| 1481 | run_tests_once(); |
| 1482 | |
| 1483 | printf("done (all tests OK)\n"); |
| 1484 | return 0; |
| 1485 | } |