xref: /linux/tools/testing/selftests/mm/protection_keys.c (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Tests Memory Protection Keys (see Documentation/core-api/protection-keys.rst)
4  *
5  * There are examples in here of:
6  *  * how to set protection keys on memory
7  *  * how to set/clear bits in pkey registers (the rights register)
8  *  * how to handle SEGV_PKUERR 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 -mxsave      -o protection_keys    -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
22  *	gcc -mxsave -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
23  */
24 #define _GNU_SOURCE
25 #define __SANE_USERSPACE_TYPES__
26 #include <errno.h>
27 #include <linux/elf.h>
28 #include <linux/futex.h>
29 #include <time.h>
30 #include <sys/time.h>
31 #include <sys/syscall.h>
32 #include <string.h>
33 #include <stdio.h>
34 #include <stdint.h>
35 #include <stdbool.h>
36 #include <signal.h>
37 #include <assert.h>
38 #include <stdlib.h>
39 #include <ucontext.h>
40 #include <sys/mman.h>
41 #include <sys/types.h>
42 #include <sys/wait.h>
43 #include <sys/stat.h>
44 #include <fcntl.h>
45 #include <asm-generic/unistd.h>
46 #include <sys/ptrace.h>
47 #include <setjmp.h>
48 
49 #include "pkey-helpers.h"
50 
51 int iteration_nr = 1;
52 int test_nr;
53 
54 u64 shadow_pkey_reg;
55 int dprint_in_signal;
56 char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];
57 
cat_into_file(char * str,char * file)58 void cat_into_file(char *str, char *file)
59 {
60 	int fd = open(file, O_RDWR);
61 	int ret;
62 
63 	dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
64 	/*
65 	 * these need to be raw because they are called under
66 	 * pkey_assert()
67 	 */
68 	if (fd < 0) {
69 		fprintf(stderr, "error opening '%s'\n", str);
70 		perror("error: ");
71 		exit(__LINE__);
72 	}
73 
74 	ret = write(fd, str, strlen(str));
75 	if (ret != strlen(str)) {
76 		perror("write to file failed");
77 		fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
78 		exit(__LINE__);
79 	}
80 	close(fd);
81 }
82 
83 #if CONTROL_TRACING > 0
84 static int warned_tracing;
tracing_root_ok(void)85 int tracing_root_ok(void)
86 {
87 	if (geteuid() != 0) {
88 		if (!warned_tracing)
89 			fprintf(stderr, "WARNING: not run as root, "
90 					"can not do tracing control\n");
91 		warned_tracing = 1;
92 		return 0;
93 	}
94 	return 1;
95 }
96 #endif
97 
tracing_on(void)98 void tracing_on(void)
99 {
100 #if CONTROL_TRACING > 0
101 #define TRACEDIR "/sys/kernel/tracing"
102 	char pidstr[32];
103 
104 	if (!tracing_root_ok())
105 		return;
106 
107 	sprintf(pidstr, "%d", getpid());
108 	cat_into_file("0", TRACEDIR "/tracing_on");
109 	cat_into_file("\n", TRACEDIR "/trace");
110 	if (1) {
111 		cat_into_file("function_graph", TRACEDIR "/current_tracer");
112 		cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
113 	} else {
114 		cat_into_file("nop", TRACEDIR "/current_tracer");
115 	}
116 	cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
117 	cat_into_file("1", TRACEDIR "/tracing_on");
118 	dprintf1("enabled tracing\n");
119 #endif
120 }
121 
tracing_off(void)122 void tracing_off(void)
123 {
124 #if CONTROL_TRACING > 0
125 	if (!tracing_root_ok())
126 		return;
127 	cat_into_file("0", "/sys/kernel/tracing/tracing_on");
128 #endif
129 }
130 
abort_hooks(void)131 void abort_hooks(void)
132 {
133 	fprintf(stderr, "running %s()...\n", __func__);
134 	tracing_off();
135 #ifdef SLEEP_ON_ABORT
136 	sleep(SLEEP_ON_ABORT);
137 #endif
138 }
139 
140 /*
141  * This attempts to have roughly a page of instructions followed by a few
142  * instructions that do a write, and another page of instructions.  That
143  * way, we are pretty sure that the write is in the second page of
144  * instructions and has at least a page of padding behind it.
145  *
146  * *That* lets us be sure to madvise() away the write instruction, which
147  * will then fault, which makes sure that the fault code handles
148  * execute-only memory properly.
149  */
150 #if defined(__powerpc64__) || defined(__aarch64__)
151 /* This way, both 4K and 64K alignment are maintained */
152 __attribute__((__aligned__(65536)))
153 #else
154 __attribute__((__aligned__(PAGE_SIZE)))
155 #endif
lots_o_noops_around_write(int * write_to_me)156 void lots_o_noops_around_write(int *write_to_me)
157 {
158 	dprintf3("running %s()\n", __func__);
159 	__page_o_noops();
160 	/* Assume this happens in the second page of instructions: */
161 	*write_to_me = __LINE__;
162 	/* pad out by another page: */
163 	__page_o_noops();
164 	dprintf3("%s() done\n", __func__);
165 }
166 
dump_mem(void * dumpme,int len_bytes)167 void dump_mem(void *dumpme, int len_bytes)
168 {
169 	char *c = (void *)dumpme;
170 	int i;
171 
172 	for (i = 0; i < len_bytes; i += sizeof(u64)) {
173 		u64 *ptr = (u64 *)(c + i);
174 		dprintf1("dump[%03d][@%p]: %016llx\n", i, ptr, *ptr);
175 	}
176 }
177 
hw_pkey_get(int pkey,unsigned long flags)178 static u32 hw_pkey_get(int pkey, unsigned long flags)
179 {
180 	u64 pkey_reg = __read_pkey_reg();
181 
182 	dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
183 			__func__, pkey, flags, 0, 0);
184 	dprintf2("%s() raw pkey_reg: %016llx\n", __func__, pkey_reg);
185 
186 	return (u32) get_pkey_bits(pkey_reg, pkey);
187 }
188 
hw_pkey_set(int pkey,unsigned long rights,unsigned long flags)189 static int hw_pkey_set(int pkey, unsigned long rights, unsigned long flags)
190 {
191 	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
192 	u64 old_pkey_reg = __read_pkey_reg();
193 	u64 new_pkey_reg;
194 
195 	/* make sure that 'rights' only contains the bits we expect: */
196 	assert(!(rights & ~mask));
197 
198 	/* modify bits accordingly in old pkey_reg and assign it */
199 	new_pkey_reg = set_pkey_bits(old_pkey_reg, pkey, rights);
200 
201 	__write_pkey_reg(new_pkey_reg);
202 
203 	dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x"
204 		" pkey_reg now: %016llx old_pkey_reg: %016llx\n",
205 		__func__, pkey, rights, flags, 0, __read_pkey_reg(),
206 		old_pkey_reg);
207 	return 0;
208 }
209 
pkey_disable_set(int pkey,int flags)210 void pkey_disable_set(int pkey, int flags)
211 {
212 	unsigned long syscall_flags = 0;
213 	int ret;
214 	int pkey_rights;
215 
216 	dprintf1("START->%s(%d, 0x%x)\n", __func__,
217 		pkey, flags);
218 	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
219 
220 	pkey_rights = hw_pkey_get(pkey, syscall_flags);
221 
222 	dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
223 			pkey, pkey, pkey_rights);
224 
225 	pkey_assert(pkey_rights >= 0);
226 
227 	pkey_rights |= flags;
228 
229 	ret = hw_pkey_set(pkey, pkey_rights, syscall_flags);
230 	assert(!ret);
231 	/* pkey_reg and flags have the same format */
232 	shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights);
233 	dprintf1("%s(%d) shadow: 0x%016llx\n",
234 		__func__, pkey, shadow_pkey_reg);
235 
236 	pkey_assert(ret >= 0);
237 
238 	pkey_rights = hw_pkey_get(pkey, syscall_flags);
239 	dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
240 			pkey, pkey, pkey_rights);
241 
242 	dprintf1("%s(%d) pkey_reg: 0x%016llx\n",
243 		__func__, pkey, read_pkey_reg());
244 	dprintf1("END<---%s(%d, 0x%x)\n", __func__,
245 		pkey, flags);
246 }
247 
pkey_disable_clear(int pkey,int flags)248 void pkey_disable_clear(int pkey, int flags)
249 {
250 	unsigned long syscall_flags = 0;
251 	int ret;
252 	int pkey_rights = hw_pkey_get(pkey, syscall_flags);
253 
254 	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
255 
256 	dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
257 			pkey, pkey, pkey_rights);
258 	pkey_assert(pkey_rights >= 0);
259 
260 	pkey_rights &= ~flags;
261 
262 	ret = hw_pkey_set(pkey, pkey_rights, 0);
263 	shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, pkey, pkey_rights);
264 	pkey_assert(ret >= 0);
265 
266 	pkey_rights = hw_pkey_get(pkey, syscall_flags);
267 	dprintf1("%s(%d) hw_pkey_get(%d): %x\n", __func__,
268 			pkey, pkey, pkey_rights);
269 
270 	dprintf1("%s(%d) pkey_reg: 0x%016llx\n", __func__,
271 			pkey, read_pkey_reg());
272 }
273 
pkey_write_allow(int pkey)274 void pkey_write_allow(int pkey)
275 {
276 	pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
277 }
pkey_write_deny(int pkey)278 void pkey_write_deny(int pkey)
279 {
280 	pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
281 }
pkey_access_allow(int pkey)282 void pkey_access_allow(int pkey)
283 {
284 	pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
285 }
pkey_access_deny(int pkey)286 void pkey_access_deny(int pkey)
287 {
288 	pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
289 }
290 
si_code_str(int si_code)291 static char *si_code_str(int si_code)
292 {
293 	if (si_code == SEGV_MAPERR)
294 		return "SEGV_MAPERR";
295 	if (si_code == SEGV_ACCERR)
296 		return "SEGV_ACCERR";
297 	if (si_code == SEGV_BNDERR)
298 		return "SEGV_BNDERR";
299 	if (si_code == SEGV_PKUERR)
300 		return "SEGV_PKUERR";
301 	return "UNKNOWN";
302 }
303 
304 int pkey_faults;
305 int last_si_pkey = -1;
signal_handler(int signum,siginfo_t * si,void * vucontext)306 void signal_handler(int signum, siginfo_t *si, void *vucontext)
307 {
308 	ucontext_t *uctxt = vucontext;
309 	int trapno;
310 	unsigned long ip;
311 #ifdef MCONTEXT_FPREGS
312 	char *fpregs;
313 #endif
314 #if defined(__i386__) || defined(__x86_64__) /* arch */
315 	u32 *pkey_reg_ptr;
316 	int pkey_reg_offset;
317 #endif /* arch */
318 	u64 siginfo_pkey;
319 	u32 *si_pkey_ptr;
320 
321 	dprint_in_signal = 1;
322 	dprintf1(">>>>===============SIGSEGV============================\n");
323 	dprintf1("%s()::%d, pkey_reg: 0x%016llx shadow: %016llx\n",
324 			__func__, __LINE__,
325 			__read_pkey_reg(), shadow_pkey_reg);
326 
327 	trapno = MCONTEXT_TRAPNO(uctxt->uc_mcontext);
328 	ip = MCONTEXT_IP(uctxt->uc_mcontext);
329 #ifdef MCONTEXT_FPREGS
330 	fpregs = (char *) uctxt->uc_mcontext.fpregs;
331 #endif
332 
333 	dprintf2("%s() trapno: %d ip: 0x%016lx info->si_code: %s/%d\n",
334 			__func__, trapno, ip, si_code_str(si->si_code),
335 			si->si_code);
336 
337 #if defined(__i386__) || defined(__x86_64__) /* arch */
338 #ifdef __i386__
339 	/*
340 	 * 32-bit has some extra padding so that userspace can tell whether
341 	 * the XSTATE header is present in addition to the "legacy" FPU
342 	 * state.  We just assume that it is here.
343 	 */
344 	fpregs += 0x70;
345 #endif /* i386 */
346 	pkey_reg_offset = pkey_reg_xstate_offset();
347 	pkey_reg_ptr = (void *)(&fpregs[pkey_reg_offset]);
348 
349 	/*
350 	 * If we got a PKEY fault, we *HAVE* to have at least one bit set in
351 	 * here.
352 	 */
353 	dprintf1("pkey_reg_xstate_offset: %d\n", pkey_reg_xstate_offset());
354 	if (DEBUG_LEVEL > 4)
355 		dump_mem(pkey_reg_ptr - 128, 256);
356 	pkey_assert(*pkey_reg_ptr);
357 #endif /* arch */
358 
359 	dprintf1("siginfo: %p\n", si);
360 #ifdef MCONTEXT_FPREGS
361 	dprintf1(" fpregs: %p\n", fpregs);
362 #endif
363 
364 	if ((si->si_code == SEGV_MAPERR) ||
365 	    (si->si_code == SEGV_ACCERR) ||
366 	    (si->si_code == SEGV_BNDERR)) {
367 		printf("non-PK si_code, exiting...\n");
368 		exit(4);
369 	}
370 
371 	si_pkey_ptr = siginfo_get_pkey_ptr(si);
372 	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
373 	dump_mem((u8 *)si_pkey_ptr - 8, 24);
374 	siginfo_pkey = *si_pkey_ptr;
375 	pkey_assert(siginfo_pkey < NR_PKEYS);
376 	last_si_pkey = siginfo_pkey;
377 
378 	/*
379 	 * need __read_pkey_reg() version so we do not do shadow_pkey_reg
380 	 * checking
381 	 */
382 	dprintf1("signal pkey_reg from  pkey_reg: %016llx\n",
383 			__read_pkey_reg());
384 	dprintf1("pkey from siginfo: %016llx\n", siginfo_pkey);
385 #if defined(__i386__) || defined(__x86_64__) /* arch */
386 	dprintf1("signal pkey_reg from xsave: %08x\n", *pkey_reg_ptr);
387 	*(u64 *)pkey_reg_ptr = 0x00000000;
388 	dprintf1("WARNING: set PKEY_REG=0 to allow faulting instruction to continue\n");
389 #elif defined(__powerpc64__) /* arch */
390 	/* restore access and let the faulting instruction continue */
391 	pkey_access_allow(siginfo_pkey);
392 #elif defined(__aarch64__)
393 	aarch64_write_signal_pkey(uctxt, PKEY_ALLOW_ALL);
394 #endif /* arch */
395 	pkey_faults++;
396 	dprintf1("<<<<==================================================\n");
397 	dprint_in_signal = 0;
398 }
399 
wait_all_children(void)400 int wait_all_children(void)
401 {
402 	int status;
403 	return waitpid(-1, &status, 0);
404 }
405 
sig_chld(int x)406 void sig_chld(int x)
407 {
408 	dprint_in_signal = 1;
409 	dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
410 	dprint_in_signal = 0;
411 }
412 
setup_sigsegv_handler(void)413 void setup_sigsegv_handler(void)
414 {
415 	int r, rs;
416 	struct sigaction newact;
417 	struct sigaction oldact;
418 
419 	/* #PF is mapped to sigsegv */
420 	int signum  = SIGSEGV;
421 
422 	newact.sa_handler = 0;
423 	newact.sa_sigaction = signal_handler;
424 
425 	/*sigset_t - signals to block while in the handler */
426 	/* get the old signal mask. */
427 	rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
428 	pkey_assert(rs == 0);
429 
430 	/* call sa_sigaction, not sa_handler*/
431 	newact.sa_flags = SA_SIGINFO;
432 
433 	newact.sa_restorer = 0;  /* void(*)(), obsolete */
434 	r = sigaction(signum, &newact, &oldact);
435 	r = sigaction(SIGALRM, &newact, &oldact);
436 	pkey_assert(r == 0);
437 }
438 
setup_handlers(void)439 void setup_handlers(void)
440 {
441 	signal(SIGCHLD, &sig_chld);
442 	setup_sigsegv_handler();
443 }
444 
fork_lazy_child(void)445 pid_t fork_lazy_child(void)
446 {
447 	pid_t forkret;
448 
449 	forkret = fork();
450 	pkey_assert(forkret >= 0);
451 	dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
452 
453 	if (!forkret) {
454 		/* in the child */
455 		while (1) {
456 			dprintf1("child sleeping...\n");
457 			sleep(30);
458 		}
459 	}
460 	return forkret;
461 }
462 
sys_mprotect_pkey(void * ptr,size_t size,unsigned long orig_prot,unsigned long pkey)463 int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
464 		unsigned long pkey)
465 {
466 	int sret;
467 
468 	dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
469 			ptr, size, orig_prot, pkey);
470 
471 	errno = 0;
472 	sret = syscall(__NR_pkey_mprotect, ptr, size, orig_prot, pkey);
473 	if (errno) {
474 		dprintf2("SYS_mprotect_key sret: %d\n", sret);
475 		dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
476 		dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
477 		if (DEBUG_LEVEL >= 2)
478 			perror("SYS_mprotect_pkey");
479 	}
480 	return sret;
481 }
482 
sys_pkey_alloc(unsigned long flags,unsigned long init_val)483 int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
484 {
485 	int ret = syscall(SYS_pkey_alloc, flags, init_val);
486 	dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
487 			__func__, flags, init_val, ret, errno);
488 	return ret;
489 }
490 
alloc_pkey(void)491 int alloc_pkey(void)
492 {
493 	int ret;
494 	unsigned long init_val = 0x0;
495 
496 	dprintf1("%s()::%d, pkey_reg: 0x%016llx shadow: %016llx\n",
497 			__func__, __LINE__, __read_pkey_reg(), shadow_pkey_reg);
498 	ret = sys_pkey_alloc(0, init_val);
499 	/*
500 	 * pkey_alloc() sets PKEY register, so we need to reflect it in
501 	 * shadow_pkey_reg:
502 	 */
503 	dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
504 			" shadow: 0x%016llx\n",
505 			__func__, __LINE__, ret, __read_pkey_reg(),
506 			shadow_pkey_reg);
507 	if (ret > 0) {
508 		/* clear both the bits: */
509 		shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, ret,
510 						~PKEY_MASK);
511 		dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
512 				" shadow: 0x%016llx\n",
513 				__func__,
514 				__LINE__, ret, __read_pkey_reg(),
515 				shadow_pkey_reg);
516 		/*
517 		 * move the new state in from init_val
518 		 * (remember, we cheated and init_val == pkey_reg format)
519 		 */
520 		shadow_pkey_reg = set_pkey_bits(shadow_pkey_reg, ret,
521 						init_val);
522 	}
523 	dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
524 			" shadow: 0x%016llx\n",
525 			__func__, __LINE__, ret, __read_pkey_reg(),
526 			shadow_pkey_reg);
527 	dprintf1("%s()::%d errno: %d\n", __func__, __LINE__, errno);
528 	/* for shadow checking: */
529 	read_pkey_reg();
530 	dprintf4("%s()::%d, ret: %d pkey_reg: 0x%016llx"
531 		 " shadow: 0x%016llx\n",
532 		__func__, __LINE__, ret, __read_pkey_reg(),
533 		shadow_pkey_reg);
534 	return ret;
535 }
536 
sys_pkey_free(unsigned long pkey)537 int sys_pkey_free(unsigned long pkey)
538 {
539 	int ret = syscall(SYS_pkey_free, pkey);
540 	dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
541 	return ret;
542 }
543 
544 /*
545  * I had a bug where pkey bits could be set by mprotect() but
546  * not cleared.  This ensures we get lots of random bit sets
547  * and clears on the vma and pte pkey bits.
548  */
alloc_random_pkey(void)549 int alloc_random_pkey(void)
550 {
551 	int max_nr_pkey_allocs;
552 	int ret;
553 	int i;
554 	int alloced_pkeys[NR_PKEYS];
555 	int nr_alloced = 0;
556 	int random_index;
557 	memset(alloced_pkeys, 0, sizeof(alloced_pkeys));
558 
559 	/* allocate every possible key and make a note of which ones we got */
560 	max_nr_pkey_allocs = NR_PKEYS;
561 	for (i = 0; i < max_nr_pkey_allocs; i++) {
562 		int new_pkey = alloc_pkey();
563 		if (new_pkey < 0)
564 			break;
565 		alloced_pkeys[nr_alloced++] = new_pkey;
566 	}
567 
568 	pkey_assert(nr_alloced > 0);
569 	/* select a random one out of the allocated ones */
570 	random_index = rand() % nr_alloced;
571 	ret = alloced_pkeys[random_index];
572 	/* now zero it out so we don't free it next */
573 	alloced_pkeys[random_index] = 0;
574 
575 	/* go through the allocated ones that we did not want and free them */
576 	for (i = 0; i < nr_alloced; i++) {
577 		int free_ret;
578 		if (!alloced_pkeys[i])
579 			continue;
580 		free_ret = sys_pkey_free(alloced_pkeys[i]);
581 		pkey_assert(!free_ret);
582 	}
583 	dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
584 			 " shadow: 0x%016llx\n", __func__,
585 			__LINE__, ret, __read_pkey_reg(), shadow_pkey_reg);
586 	return ret;
587 }
588 
mprotect_pkey(void * ptr,size_t size,unsigned long orig_prot,unsigned long pkey)589 int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
590 		unsigned long pkey)
591 {
592 	int nr_iterations = random() % 100;
593 	int ret;
594 
595 	while (0) {
596 		int rpkey = alloc_random_pkey();
597 		ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
598 		dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
599 				ptr, size, orig_prot, pkey, ret);
600 		if (nr_iterations-- < 0)
601 			break;
602 
603 		dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
604 			" shadow: 0x%016llx\n",
605 			__func__, __LINE__, ret, __read_pkey_reg(),
606 			shadow_pkey_reg);
607 		sys_pkey_free(rpkey);
608 		dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
609 			" shadow: 0x%016llx\n",
610 			__func__, __LINE__, ret, __read_pkey_reg(),
611 			shadow_pkey_reg);
612 	}
613 	pkey_assert(pkey < NR_PKEYS);
614 
615 	ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
616 	dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
617 			ptr, size, orig_prot, pkey, ret);
618 	pkey_assert(!ret);
619 	dprintf1("%s()::%d, ret: %d pkey_reg: 0x%016llx"
620 			" shadow: 0x%016llx\n", __func__,
621 			__LINE__, ret, __read_pkey_reg(), shadow_pkey_reg);
622 	return ret;
623 }
624 
625 struct pkey_malloc_record {
626 	void *ptr;
627 	long size;
628 	int prot;
629 };
630 struct pkey_malloc_record *pkey_malloc_records;
631 struct pkey_malloc_record *pkey_last_malloc_record;
632 long nr_pkey_malloc_records;
record_pkey_malloc(void * ptr,long size,int prot)633 void record_pkey_malloc(void *ptr, long size, int prot)
634 {
635 	long i;
636 	struct pkey_malloc_record *rec = NULL;
637 
638 	for (i = 0; i < nr_pkey_malloc_records; i++) {
639 		rec = &pkey_malloc_records[i];
640 		/* find a free record */
641 		if (rec)
642 			break;
643 	}
644 	if (!rec) {
645 		/* every record is full */
646 		size_t old_nr_records = nr_pkey_malloc_records;
647 		size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
648 		size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
649 		dprintf2("new_nr_records: %zd\n", new_nr_records);
650 		dprintf2("new_size: %zd\n", new_size);
651 		pkey_malloc_records = realloc(pkey_malloc_records, new_size);
652 		pkey_assert(pkey_malloc_records != NULL);
653 		rec = &pkey_malloc_records[nr_pkey_malloc_records];
654 		/*
655 		 * realloc() does not initialize memory, so zero it from
656 		 * the first new record all the way to the end.
657 		 */
658 		for (i = 0; i < new_nr_records - old_nr_records; i++)
659 			memset(rec + i, 0, sizeof(*rec));
660 	}
661 	dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
662 		(int)(rec - pkey_malloc_records), rec, ptr, size);
663 	rec->ptr = ptr;
664 	rec->size = size;
665 	rec->prot = prot;
666 	pkey_last_malloc_record = rec;
667 	nr_pkey_malloc_records++;
668 }
669 
free_pkey_malloc(void * ptr)670 void free_pkey_malloc(void *ptr)
671 {
672 	long i;
673 	int ret;
674 	dprintf3("%s(%p)\n", __func__, ptr);
675 	for (i = 0; i < nr_pkey_malloc_records; i++) {
676 		struct pkey_malloc_record *rec = &pkey_malloc_records[i];
677 		dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
678 				ptr, i, rec, rec->ptr, rec->size);
679 		if ((ptr <  rec->ptr) ||
680 		    (ptr >= rec->ptr + rec->size))
681 			continue;
682 
683 		dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
684 				ptr, i, rec, rec->ptr, rec->size);
685 		nr_pkey_malloc_records--;
686 		ret = munmap(rec->ptr, rec->size);
687 		dprintf3("munmap ret: %d\n", ret);
688 		pkey_assert(!ret);
689 		dprintf3("clearing rec->ptr, rec: %p\n", rec);
690 		rec->ptr = NULL;
691 		dprintf3("done clearing rec->ptr, rec: %p\n", rec);
692 		return;
693 	}
694 	pkey_assert(false);
695 }
696 
697 
malloc_pkey_with_mprotect(long size,int prot,u16 pkey)698 void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
699 {
700 	void *ptr;
701 	int ret;
702 
703 	read_pkey_reg();
704 	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
705 			size, prot, pkey);
706 	pkey_assert(pkey < NR_PKEYS);
707 	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
708 	pkey_assert(ptr != (void *)-1);
709 	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
710 	pkey_assert(!ret);
711 	record_pkey_malloc(ptr, size, prot);
712 	read_pkey_reg();
713 
714 	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
715 	return ptr;
716 }
717 
malloc_pkey_anon_huge(long size,int prot,u16 pkey)718 void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
719 {
720 	int ret;
721 	void *ptr;
722 
723 	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
724 			size, prot, pkey);
725 	/*
726 	 * Guarantee we can fit at least one huge page in the resulting
727 	 * allocation by allocating space for 2:
728 	 */
729 	size = ALIGN_UP(size, HPAGE_SIZE * 2);
730 	ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
731 	pkey_assert(ptr != (void *)-1);
732 	record_pkey_malloc(ptr, size, prot);
733 	mprotect_pkey(ptr, size, prot, pkey);
734 
735 	dprintf1("unaligned ptr: %p\n", ptr);
736 	ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
737 	dprintf1("  aligned ptr: %p\n", ptr);
738 	ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
739 	dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
740 	ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
741 	dprintf1("MADV_WILLNEED ret: %d\n", ret);
742 	memset(ptr, 0, HPAGE_SIZE);
743 
744 	dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
745 	return ptr;
746 }
747 
748 int hugetlb_setup_ok;
749 #define SYSFS_FMT_NR_HUGE_PAGES "/sys/kernel/mm/hugepages/hugepages-%ldkB/nr_hugepages"
750 #define GET_NR_HUGE_PAGES 10
setup_hugetlbfs(void)751 void setup_hugetlbfs(void)
752 {
753 	int err;
754 	int fd;
755 	char buf[256];
756 	long hpagesz_kb;
757 	long hpagesz_mb;
758 
759 	if (geteuid() != 0) {
760 		fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
761 		return;
762 	}
763 
764 	cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");
765 
766 	/*
767 	 * Now go make sure that we got the pages and that they
768 	 * are PMD-level pages. Someone might have made PUD-level
769 	 * pages the default.
770 	 */
771 	hpagesz_kb = HPAGE_SIZE / 1024;
772 	hpagesz_mb = hpagesz_kb / 1024;
773 	sprintf(buf, SYSFS_FMT_NR_HUGE_PAGES, hpagesz_kb);
774 	fd = open(buf, O_RDONLY);
775 	if (fd < 0) {
776 		fprintf(stderr, "opening sysfs %ldM hugetlb config: %s\n",
777 			hpagesz_mb, strerror(errno));
778 		return;
779 	}
780 
781 	/* -1 to guarantee leaving the trailing \0 */
782 	err = read(fd, buf, sizeof(buf)-1);
783 	close(fd);
784 	if (err <= 0) {
785 		fprintf(stderr, "reading sysfs %ldM hugetlb config: %s\n",
786 			hpagesz_mb, strerror(errno));
787 		return;
788 	}
789 
790 	if (atoi(buf) != GET_NR_HUGE_PAGES) {
791 		fprintf(stderr, "could not confirm %ldM pages, got: '%s' expected %d\n",
792 			hpagesz_mb, buf, GET_NR_HUGE_PAGES);
793 		return;
794 	}
795 
796 	hugetlb_setup_ok = 1;
797 }
798 
malloc_pkey_hugetlb(long size,int prot,u16 pkey)799 void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
800 {
801 	void *ptr;
802 	int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;
803 
804 	if (!hugetlb_setup_ok)
805 		return PTR_ERR_ENOTSUP;
806 
807 	dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
808 	size = ALIGN_UP(size, HPAGE_SIZE * 2);
809 	pkey_assert(pkey < NR_PKEYS);
810 	ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
811 	pkey_assert(ptr != (void *)-1);
812 	mprotect_pkey(ptr, size, prot, pkey);
813 
814 	record_pkey_malloc(ptr, size, prot);
815 
816 	dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
817 	return ptr;
818 }
819 
malloc_pkey_mmap_dax(long size,int prot,u16 pkey)820 void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
821 {
822 	void *ptr;
823 	int fd;
824 
825 	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
826 			size, prot, pkey);
827 	pkey_assert(pkey < NR_PKEYS);
828 	fd = open("/dax/foo", O_RDWR);
829 	pkey_assert(fd >= 0);
830 
831 	ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
832 	pkey_assert(ptr != (void *)-1);
833 
834 	mprotect_pkey(ptr, size, prot, pkey);
835 
836 	record_pkey_malloc(ptr, size, prot);
837 
838 	dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
839 	close(fd);
840 	return ptr;
841 }
842 
843 void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {
844 
845 	malloc_pkey_with_mprotect,
846 	malloc_pkey_with_mprotect_subpage,
847 	malloc_pkey_anon_huge,
848 	malloc_pkey_hugetlb
849 /* can not do direct with the pkey_mprotect() API:
850 	malloc_pkey_mmap_direct,
851 	malloc_pkey_mmap_dax,
852 */
853 };
854 
malloc_pkey(long size,int prot,u16 pkey)855 void *malloc_pkey(long size, int prot, u16 pkey)
856 {
857 	void *ret;
858 	static int malloc_type;
859 	int nr_malloc_types = ARRAY_SIZE(pkey_malloc);
860 
861 	pkey_assert(pkey < NR_PKEYS);
862 
863 	while (1) {
864 		pkey_assert(malloc_type < nr_malloc_types);
865 
866 		ret = pkey_malloc[malloc_type](size, prot, pkey);
867 		pkey_assert(ret != (void *)-1);
868 
869 		malloc_type++;
870 		if (malloc_type >= nr_malloc_types)
871 			malloc_type = (random()%nr_malloc_types);
872 
873 		/* try again if the malloc_type we tried is unsupported */
874 		if (ret == PTR_ERR_ENOTSUP)
875 			continue;
876 
877 		break;
878 	}
879 
880 	dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
881 			size, prot, pkey, ret);
882 	return ret;
883 }
884 
885 int last_pkey_faults;
886 #define UNKNOWN_PKEY -2
expected_pkey_fault(int pkey)887 void expected_pkey_fault(int pkey)
888 {
889 	dprintf2("%s(): last_pkey_faults: %d pkey_faults: %d\n",
890 			__func__, last_pkey_faults, pkey_faults);
891 	dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
892 	pkey_assert(last_pkey_faults + 1 == pkey_faults);
893 
894        /*
895 	* For exec-only memory, we do not know the pkey in
896 	* advance, so skip this check.
897 	*/
898 	if (pkey != UNKNOWN_PKEY)
899 		pkey_assert(last_si_pkey == pkey);
900 
901 #if defined(__i386__) || defined(__x86_64__) /* arch */
902 	/*
903 	 * The signal handler shold have cleared out PKEY register to let the
904 	 * test program continue.  We now have to restore it.
905 	 */
906 	if (__read_pkey_reg() != 0)
907 #elif defined(__aarch64__)
908 	if (__read_pkey_reg() != PKEY_ALLOW_ALL)
909 #else
910 	if (__read_pkey_reg() != shadow_pkey_reg)
911 #endif /* arch */
912 		pkey_assert(0);
913 
914 	__write_pkey_reg(shadow_pkey_reg);
915 	dprintf1("%s() set pkey_reg=%016llx to restore state after signal "
916 		       "nuked it\n", __func__, shadow_pkey_reg);
917 	last_pkey_faults = pkey_faults;
918 	last_si_pkey = -1;
919 }
920 
921 #define do_not_expect_pkey_fault(msg)	do {			\
922 	if (last_pkey_faults != pkey_faults)			\
923 		dprintf0("unexpected PKey fault: %s\n", msg);	\
924 	pkey_assert(last_pkey_faults == pkey_faults);		\
925 } while (0)
926 
927 int test_fds[10] = { -1 };
928 int nr_test_fds;
__save_test_fd(int fd)929 void __save_test_fd(int fd)
930 {
931 	pkey_assert(fd >= 0);
932 	pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
933 	test_fds[nr_test_fds] = fd;
934 	nr_test_fds++;
935 }
936 
get_test_read_fd(void)937 int get_test_read_fd(void)
938 {
939 	int test_fd = open("/etc/passwd", O_RDONLY);
940 	__save_test_fd(test_fd);
941 	return test_fd;
942 }
943 
close_test_fds(void)944 void close_test_fds(void)
945 {
946 	int i;
947 
948 	for (i = 0; i < nr_test_fds; i++) {
949 		if (test_fds[i] < 0)
950 			continue;
951 		close(test_fds[i]);
952 		test_fds[i] = -1;
953 	}
954 	nr_test_fds = 0;
955 }
956 
test_pkey_alloc_free_attach_pkey0(int * ptr,u16 pkey)957 void test_pkey_alloc_free_attach_pkey0(int *ptr, u16 pkey)
958 {
959 	int i, err;
960 	int max_nr_pkey_allocs;
961 	int alloced_pkeys[NR_PKEYS];
962 	int nr_alloced = 0;
963 	long size;
964 
965 	pkey_assert(pkey_last_malloc_record);
966 	size = pkey_last_malloc_record->size;
967 	/*
968 	 * This is a bit of a hack.  But mprotect() requires
969 	 * huge-page-aligned sizes when operating on hugetlbfs.
970 	 * So, make sure that we use something that's a multiple
971 	 * of a huge page when we can.
972 	 */
973 	if (size >= HPAGE_SIZE)
974 		size = HPAGE_SIZE;
975 
976 	/* allocate every possible key and make sure key-0 never got allocated */
977 	max_nr_pkey_allocs = NR_PKEYS;
978 	for (i = 0; i < max_nr_pkey_allocs; i++) {
979 		int new_pkey = alloc_pkey();
980 		pkey_assert(new_pkey != 0);
981 
982 		if (new_pkey < 0)
983 			break;
984 		alloced_pkeys[nr_alloced++] = new_pkey;
985 	}
986 	/* free all the allocated keys */
987 	for (i = 0; i < nr_alloced; i++) {
988 		int free_ret;
989 
990 		if (!alloced_pkeys[i])
991 			continue;
992 		free_ret = sys_pkey_free(alloced_pkeys[i]);
993 		pkey_assert(!free_ret);
994 	}
995 
996 	/* attach key-0 in various modes */
997 	err = sys_mprotect_pkey(ptr, size, PROT_READ, 0);
998 	pkey_assert(!err);
999 	err = sys_mprotect_pkey(ptr, size, PROT_WRITE, 0);
1000 	pkey_assert(!err);
1001 	err = sys_mprotect_pkey(ptr, size, PROT_EXEC, 0);
1002 	pkey_assert(!err);
1003 	err = sys_mprotect_pkey(ptr, size, PROT_READ|PROT_WRITE, 0);
1004 	pkey_assert(!err);
1005 	err = sys_mprotect_pkey(ptr, size, PROT_READ|PROT_WRITE|PROT_EXEC, 0);
1006 	pkey_assert(!err);
1007 }
1008 
test_read_of_write_disabled_region(int * ptr,u16 pkey)1009 void test_read_of_write_disabled_region(int *ptr, u16 pkey)
1010 {
1011 	int ptr_contents;
1012 
1013 	dprintf1("disabling write access to PKEY[1], doing read\n");
1014 	pkey_write_deny(pkey);
1015 	ptr_contents = read_ptr(ptr);
1016 	dprintf1("*ptr: %d\n", ptr_contents);
1017 	dprintf1("\n");
1018 }
test_read_of_access_disabled_region(int * ptr,u16 pkey)1019 void test_read_of_access_disabled_region(int *ptr, u16 pkey)
1020 {
1021 	int ptr_contents;
1022 
1023 	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
1024 	read_pkey_reg();
1025 	pkey_access_deny(pkey);
1026 	ptr_contents = read_ptr(ptr);
1027 	dprintf1("*ptr: %d\n", ptr_contents);
1028 	expected_pkey_fault(pkey);
1029 }
1030 
test_read_of_access_disabled_region_with_page_already_mapped(int * ptr,u16 pkey)1031 void test_read_of_access_disabled_region_with_page_already_mapped(int *ptr,
1032 		u16 pkey)
1033 {
1034 	int ptr_contents;
1035 
1036 	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n",
1037 				pkey, ptr);
1038 	ptr_contents = read_ptr(ptr);
1039 	dprintf1("reading ptr before disabling the read : %d\n",
1040 			ptr_contents);
1041 	read_pkey_reg();
1042 	pkey_access_deny(pkey);
1043 	ptr_contents = read_ptr(ptr);
1044 	dprintf1("*ptr: %d\n", ptr_contents);
1045 	expected_pkey_fault(pkey);
1046 }
1047 
test_write_of_write_disabled_region_with_page_already_mapped(int * ptr,u16 pkey)1048 void test_write_of_write_disabled_region_with_page_already_mapped(int *ptr,
1049 		u16 pkey)
1050 {
1051 	*ptr = __LINE__;
1052 	dprintf1("disabling write access; after accessing the page, "
1053 		"to PKEY[%02d], doing write\n", pkey);
1054 	pkey_write_deny(pkey);
1055 	*ptr = __LINE__;
1056 	expected_pkey_fault(pkey);
1057 }
1058 
test_write_of_write_disabled_region(int * ptr,u16 pkey)1059 void test_write_of_write_disabled_region(int *ptr, u16 pkey)
1060 {
1061 	dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
1062 	pkey_write_deny(pkey);
1063 	*ptr = __LINE__;
1064 	expected_pkey_fault(pkey);
1065 }
test_write_of_access_disabled_region(int * ptr,u16 pkey)1066 void test_write_of_access_disabled_region(int *ptr, u16 pkey)
1067 {
1068 	dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
1069 	pkey_access_deny(pkey);
1070 	*ptr = __LINE__;
1071 	expected_pkey_fault(pkey);
1072 }
1073 
test_write_of_access_disabled_region_with_page_already_mapped(int * ptr,u16 pkey)1074 void test_write_of_access_disabled_region_with_page_already_mapped(int *ptr,
1075 			u16 pkey)
1076 {
1077 	*ptr = __LINE__;
1078 	dprintf1("disabling access; after accessing the page, "
1079 		" to PKEY[%02d], doing write\n", pkey);
1080 	pkey_access_deny(pkey);
1081 	*ptr = __LINE__;
1082 	expected_pkey_fault(pkey);
1083 }
1084 
test_kernel_write_of_access_disabled_region(int * ptr,u16 pkey)1085 void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
1086 {
1087 	int ret;
1088 	int test_fd = get_test_read_fd();
1089 
1090 	dprintf1("disabling access to PKEY[%02d], "
1091 		 "having kernel read() to buffer\n", pkey);
1092 	pkey_access_deny(pkey);
1093 	ret = read(test_fd, ptr, 1);
1094 	dprintf1("read ret: %d\n", ret);
1095 	pkey_assert(ret);
1096 }
test_kernel_write_of_write_disabled_region(int * ptr,u16 pkey)1097 void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
1098 {
1099 	int ret;
1100 	int test_fd = get_test_read_fd();
1101 
1102 	pkey_write_deny(pkey);
1103 	ret = read(test_fd, ptr, 100);
1104 	dprintf1("read ret: %d\n", ret);
1105 	if (ret < 0 && (DEBUG_LEVEL > 0))
1106 		perror("verbose read result (OK for this to be bad)");
1107 	pkey_assert(ret);
1108 }
1109 
test_kernel_gup_of_access_disabled_region(int * ptr,u16 pkey)1110 void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
1111 {
1112 	int pipe_ret, vmsplice_ret;
1113 	struct iovec iov;
1114 	int pipe_fds[2];
1115 
1116 	pipe_ret = pipe(pipe_fds);
1117 
1118 	pkey_assert(pipe_ret == 0);
1119 	dprintf1("disabling access to PKEY[%02d], "
1120 		 "having kernel vmsplice from buffer\n", pkey);
1121 	pkey_access_deny(pkey);
1122 	iov.iov_base = ptr;
1123 	iov.iov_len = PAGE_SIZE;
1124 	vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
1125 	dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
1126 	pkey_assert(vmsplice_ret == -1);
1127 
1128 	close(pipe_fds[0]);
1129 	close(pipe_fds[1]);
1130 }
1131 
test_kernel_gup_write_to_write_disabled_region(int * ptr,u16 pkey)1132 void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
1133 {
1134 	int ignored = 0xdada;
1135 	int futex_ret;
1136 	int some_int = __LINE__;
1137 
1138 	dprintf1("disabling write to PKEY[%02d], "
1139 		 "doing futex gunk in buffer\n", pkey);
1140 	*ptr = some_int;
1141 	pkey_write_deny(pkey);
1142 	futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
1143 			&ignored, ignored);
1144 	if (DEBUG_LEVEL > 0)
1145 		perror("futex");
1146 	dprintf1("futex() ret: %d\n", futex_ret);
1147 }
1148 
1149 /* Assumes that all pkeys other than 'pkey' are unallocated */
test_pkey_syscalls_on_non_allocated_pkey(int * ptr,u16 pkey)1150 void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
1151 {
1152 	int err;
1153 	int i;
1154 
1155 	/* Note: 0 is the default pkey, so don't mess with it */
1156 	for (i = 1; i < NR_PKEYS; i++) {
1157 		if (pkey == i)
1158 			continue;
1159 
1160 		dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
1161 		err = sys_pkey_free(i);
1162 		pkey_assert(err);
1163 
1164 		err = sys_pkey_free(i);
1165 		pkey_assert(err);
1166 
1167 		err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
1168 		pkey_assert(err);
1169 	}
1170 }
1171 
1172 /* Assumes that all pkeys other than 'pkey' are unallocated */
test_pkey_syscalls_bad_args(int * ptr,u16 pkey)1173 void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
1174 {
1175 	int err;
1176 	int bad_pkey = NR_PKEYS+99;
1177 
1178 	/* pass a known-invalid pkey in: */
1179 	err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
1180 	pkey_assert(err);
1181 }
1182 
become_child(void)1183 void become_child(void)
1184 {
1185 	pid_t forkret;
1186 
1187 	forkret = fork();
1188 	pkey_assert(forkret >= 0);
1189 	dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);
1190 
1191 	if (!forkret) {
1192 		/* in the child */
1193 		return;
1194 	}
1195 	exit(0);
1196 }
1197 
1198 /* Assumes that all pkeys other than 'pkey' are unallocated */
test_pkey_alloc_exhaust(int * ptr,u16 pkey)1199 void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
1200 {
1201 	int err;
1202 	int allocated_pkeys[NR_PKEYS] = {0};
1203 	int nr_allocated_pkeys = 0;
1204 	int i;
1205 
1206 	for (i = 0; i < NR_PKEYS*3; i++) {
1207 		int new_pkey;
1208 		dprintf1("%s() alloc loop: %d\n", __func__, i);
1209 		new_pkey = alloc_pkey();
1210 		dprintf4("%s()::%d, err: %d pkey_reg: 0x%016llx"
1211 				" shadow: 0x%016llx\n",
1212 				__func__, __LINE__, err, __read_pkey_reg(),
1213 				shadow_pkey_reg);
1214 		read_pkey_reg(); /* for shadow checking */
1215 		dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
1216 		if ((new_pkey == -1) && (errno == ENOSPC)) {
1217 			dprintf2("%s() failed to allocate pkey after %d tries\n",
1218 				__func__, nr_allocated_pkeys);
1219 		} else {
1220 			/*
1221 			 * Ensure the number of successes never
1222 			 * exceeds the number of keys supported
1223 			 * in the hardware.
1224 			 */
1225 			pkey_assert(nr_allocated_pkeys < NR_PKEYS);
1226 			allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
1227 		}
1228 
1229 		/*
1230 		 * Make sure that allocation state is properly
1231 		 * preserved across fork().
1232 		 */
1233 		if (i == NR_PKEYS*2)
1234 			become_child();
1235 	}
1236 
1237 	dprintf3("%s()::%d\n", __func__, __LINE__);
1238 
1239 	/*
1240 	 * On x86:
1241 	 * There are 16 pkeys supported in hardware.  Three are
1242 	 * allocated by the time we get here:
1243 	 *   1. The default key (0)
1244 	 *   2. One possibly consumed by an execute-only mapping.
1245 	 *   3. One allocated by the test code and passed in via
1246 	 *      'pkey' to this function.
1247 	 * Ensure that we can allocate at least another 13 (16-3).
1248 	 *
1249 	 * On powerpc:
1250 	 * There are either 5, 28, 29 or 32 pkeys supported in
1251 	 * hardware depending on the page size (4K or 64K) and
1252 	 * platform (powernv or powervm). Four are allocated by
1253 	 * the time we get here. These include pkey-0, pkey-1,
1254 	 * exec-only pkey and the one allocated by the test code.
1255 	 * Ensure that we can allocate the remaining.
1256 	 */
1257 	pkey_assert(i >= (NR_PKEYS - get_arch_reserved_keys() - 1));
1258 
1259 	for (i = 0; i < nr_allocated_pkeys; i++) {
1260 		err = sys_pkey_free(allocated_pkeys[i]);
1261 		pkey_assert(!err);
1262 		read_pkey_reg(); /* for shadow checking */
1263 	}
1264 }
1265 
arch_force_pkey_reg_init(void)1266 void arch_force_pkey_reg_init(void)
1267 {
1268 #if defined(__i386__) || defined(__x86_64__) /* arch */
1269 	u64 *buf;
1270 
1271 	/*
1272 	 * All keys should be allocated and set to allow reads and
1273 	 * writes, so the register should be all 0.  If not, just
1274 	 * skip the test.
1275 	 */
1276 	if (read_pkey_reg())
1277 		return;
1278 
1279 	/*
1280 	 * Just allocate an absurd about of memory rather than
1281 	 * doing the XSAVE size enumeration dance.
1282 	 */
1283 	buf = mmap(NULL, 1*MB, PROT_READ|PROT_WRITE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
1284 
1285 	/* These __builtins require compiling with -mxsave */
1286 
1287 	/* XSAVE to build a valid buffer: */
1288 	__builtin_ia32_xsave(buf, XSTATE_PKEY);
1289 	/* Clear XSTATE_BV[PKRU]: */
1290 	buf[XSTATE_BV_OFFSET/sizeof(u64)] &= ~XSTATE_PKEY;
1291 	/* XRSTOR will likely get PKRU back to the init state: */
1292 	__builtin_ia32_xrstor(buf, XSTATE_PKEY);
1293 
1294 	munmap(buf, 1*MB);
1295 #endif
1296 }
1297 
1298 
1299 /*
1300  * This is mostly useless on ppc for now.  But it will not
1301  * hurt anything and should give some better coverage as
1302  * a long-running test that continually checks the pkey
1303  * register.
1304  */
test_pkey_init_state(int * ptr,u16 pkey)1305 void test_pkey_init_state(int *ptr, u16 pkey)
1306 {
1307 	int err;
1308 	int allocated_pkeys[NR_PKEYS] = {0};
1309 	int nr_allocated_pkeys = 0;
1310 	int i;
1311 
1312 	for (i = 0; i < NR_PKEYS; i++) {
1313 		int new_pkey = alloc_pkey();
1314 
1315 		if (new_pkey < 0)
1316 			continue;
1317 		allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
1318 	}
1319 
1320 	dprintf3("%s()::%d\n", __func__, __LINE__);
1321 
1322 	arch_force_pkey_reg_init();
1323 
1324 	/*
1325 	 * Loop for a bit, hoping to get exercise the kernel
1326 	 * context switch code.
1327 	 */
1328 	for (i = 0; i < 1000000; i++)
1329 		read_pkey_reg();
1330 
1331 	for (i = 0; i < nr_allocated_pkeys; i++) {
1332 		err = sys_pkey_free(allocated_pkeys[i]);
1333 		pkey_assert(!err);
1334 		read_pkey_reg(); /* for shadow checking */
1335 	}
1336 }
1337 
1338 /*
1339  * pkey 0 is special.  It is allocated by default, so you do not
1340  * have to call pkey_alloc() to use it first.  Make sure that it
1341  * is usable.
1342  */
test_mprotect_with_pkey_0(int * ptr,u16 pkey)1343 void test_mprotect_with_pkey_0(int *ptr, u16 pkey)
1344 {
1345 	long size;
1346 	int prot;
1347 
1348 	assert(pkey_last_malloc_record);
1349 	size = pkey_last_malloc_record->size;
1350 	/*
1351 	 * This is a bit of a hack.  But mprotect() requires
1352 	 * huge-page-aligned sizes when operating on hugetlbfs.
1353 	 * So, make sure that we use something that's a multiple
1354 	 * of a huge page when we can.
1355 	 */
1356 	if (size >= HPAGE_SIZE)
1357 		size = HPAGE_SIZE;
1358 	prot = pkey_last_malloc_record->prot;
1359 
1360 	/* Use pkey 0 */
1361 	mprotect_pkey(ptr, size, prot, 0);
1362 
1363 	/* Make sure that we can set it back to the original pkey. */
1364 	mprotect_pkey(ptr, size, prot, pkey);
1365 }
1366 
test_ptrace_of_child(int * ptr,u16 pkey)1367 void test_ptrace_of_child(int *ptr, u16 pkey)
1368 {
1369 	__attribute__((__unused__)) int peek_result;
1370 	pid_t child_pid;
1371 	void *ignored = 0;
1372 	long ret;
1373 	int status;
1374 	/*
1375 	 * This is the "control" for our little expermient.  Make sure
1376 	 * we can always access it when ptracing.
1377 	 */
1378 	int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
1379 	int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);
1380 
1381 	/*
1382 	 * Fork a child which is an exact copy of this process, of course.
1383 	 * That means we can do all of our tests via ptrace() and then plain
1384 	 * memory access and ensure they work differently.
1385 	 */
1386 	child_pid = fork_lazy_child();
1387 	dprintf1("[%d] child pid: %d\n", getpid(), child_pid);
1388 
1389 	ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
1390 	if (ret)
1391 		perror("attach");
1392 	dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
1393 	pkey_assert(ret != -1);
1394 	ret = waitpid(child_pid, &status, WUNTRACED);
1395 	if ((ret != child_pid) || !(WIFSTOPPED(status))) {
1396 		fprintf(stderr, "weird waitpid result %ld stat %x\n",
1397 				ret, status);
1398 		pkey_assert(0);
1399 	}
1400 	dprintf2("waitpid ret: %ld\n", ret);
1401 	dprintf2("waitpid status: %d\n", status);
1402 
1403 	pkey_access_deny(pkey);
1404 	pkey_write_deny(pkey);
1405 
1406 	/* Write access, untested for now:
1407 	ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
1408 	pkey_assert(ret != -1);
1409 	dprintf1("poke at %p: %ld\n", peek_at, ret);
1410 	*/
1411 
1412 	/*
1413 	 * Try to access the pkey-protected "ptr" via ptrace:
1414 	 */
1415 	ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
1416 	/* expect it to work, without an error: */
1417 	pkey_assert(ret != -1);
1418 	/* Now access from the current task, and expect an exception: */
1419 	peek_result = read_ptr(ptr);
1420 	expected_pkey_fault(pkey);
1421 
1422 	/*
1423 	 * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
1424 	 */
1425 	ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
1426 	/* expect it to work, without an error: */
1427 	pkey_assert(ret != -1);
1428 	/* Now access from the current task, and expect NO exception: */
1429 	peek_result = read_ptr(plain_ptr);
1430 	do_not_expect_pkey_fault("read plain pointer after ptrace");
1431 
1432 	ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
1433 	pkey_assert(ret != -1);
1434 
1435 	ret = kill(child_pid, SIGKILL);
1436 	pkey_assert(ret != -1);
1437 
1438 	wait(&status);
1439 
1440 	free(plain_ptr_unaligned);
1441 }
1442 
get_pointer_to_instructions(void)1443 void *get_pointer_to_instructions(void)
1444 {
1445 	void *p1;
1446 
1447 	p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
1448 	dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
1449 	/* lots_o_noops_around_write should be page-aligned already */
1450 	assert(p1 == &lots_o_noops_around_write);
1451 
1452 	/* Point 'p1' at the *second* page of the function: */
1453 	p1 += PAGE_SIZE;
1454 
1455 	/*
1456 	 * Try to ensure we fault this in on next touch to ensure
1457 	 * we get an instruction fault as opposed to a data one
1458 	 */
1459 	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
1460 
1461 	return p1;
1462 }
1463 
test_executing_on_unreadable_memory(int * ptr,u16 pkey)1464 void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
1465 {
1466 	void *p1;
1467 	int scratch;
1468 	int ptr_contents;
1469 	int ret;
1470 
1471 	p1 = get_pointer_to_instructions();
1472 	lots_o_noops_around_write(&scratch);
1473 	ptr_contents = read_ptr(p1);
1474 	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
1475 
1476 	ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
1477 	pkey_assert(!ret);
1478 	pkey_access_deny(pkey);
1479 
1480 	dprintf2("pkey_reg: %016llx\n", read_pkey_reg());
1481 
1482 	/*
1483 	 * Make sure this is an *instruction* fault
1484 	 */
1485 	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
1486 	lots_o_noops_around_write(&scratch);
1487 	do_not_expect_pkey_fault("executing on PROT_EXEC memory");
1488 	expect_fault_on_read_execonly_key(p1, pkey);
1489 
1490 	// Reset back to PROT_EXEC | PROT_READ for architectures that support
1491 	// non-PKEY execute-only permissions.
1492 	ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC | PROT_READ, (u64)pkey);
1493 	pkey_assert(!ret);
1494 }
1495 
test_implicit_mprotect_exec_only_memory(int * ptr,u16 pkey)1496 void test_implicit_mprotect_exec_only_memory(int *ptr, u16 pkey)
1497 {
1498 	void *p1;
1499 	int scratch;
1500 	int ptr_contents;
1501 	int ret;
1502 
1503 	dprintf1("%s() start\n", __func__);
1504 
1505 	p1 = get_pointer_to_instructions();
1506 	lots_o_noops_around_write(&scratch);
1507 	ptr_contents = read_ptr(p1);
1508 	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
1509 
1510 	/* Use a *normal* mprotect(), not mprotect_pkey(): */
1511 	ret = mprotect(p1, PAGE_SIZE, PROT_EXEC);
1512 	pkey_assert(!ret);
1513 
1514 	/*
1515 	 * Reset the shadow, assuming that the above mprotect()
1516 	 * correctly changed PKRU, but to an unknown value since
1517 	 * the actual allocated pkey is unknown.
1518 	 */
1519 	shadow_pkey_reg = __read_pkey_reg();
1520 
1521 	dprintf2("pkey_reg: %016llx\n", read_pkey_reg());
1522 
1523 	/* Make sure this is an *instruction* fault */
1524 	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
1525 	lots_o_noops_around_write(&scratch);
1526 	do_not_expect_pkey_fault("executing on PROT_EXEC memory");
1527 	expect_fault_on_read_execonly_key(p1, UNKNOWN_PKEY);
1528 
1529 	/*
1530 	 * Put the memory back to non-PROT_EXEC.  Should clear the
1531 	 * exec-only pkey off the VMA and allow it to be readable
1532 	 * again.  Go to PROT_NONE first to check for a kernel bug
1533 	 * that did not clear the pkey when doing PROT_NONE.
1534 	 */
1535 	ret = mprotect(p1, PAGE_SIZE, PROT_NONE);
1536 	pkey_assert(!ret);
1537 
1538 	ret = mprotect(p1, PAGE_SIZE, PROT_READ|PROT_EXEC);
1539 	pkey_assert(!ret);
1540 	ptr_contents = read_ptr(p1);
1541 	do_not_expect_pkey_fault("plain read on recently PROT_EXEC area");
1542 }
1543 
1544 #if defined(__i386__) || defined(__x86_64__)
test_ptrace_modifies_pkru(int * ptr,u16 pkey)1545 void test_ptrace_modifies_pkru(int *ptr, u16 pkey)
1546 {
1547 	u32 new_pkru;
1548 	pid_t child;
1549 	int status, ret;
1550 	int pkey_offset = pkey_reg_xstate_offset();
1551 	size_t xsave_size = cpu_max_xsave_size();
1552 	void *xsave;
1553 	u32 *pkey_register;
1554 	u64 *xstate_bv;
1555 	struct iovec iov;
1556 
1557 	new_pkru = ~read_pkey_reg();
1558 	/* Don't make PROT_EXEC mappings inaccessible */
1559 	new_pkru &= ~3;
1560 
1561 	child = fork();
1562 	pkey_assert(child >= 0);
1563 	dprintf3("[%d] fork() ret: %d\n", getpid(), child);
1564 	if (!child) {
1565 		ptrace(PTRACE_TRACEME, 0, 0, 0);
1566 		/* Stop and allow the tracer to modify PKRU directly */
1567 		raise(SIGSTOP);
1568 
1569 		/*
1570 		 * need __read_pkey_reg() version so we do not do shadow_pkey_reg
1571 		 * checking
1572 		 */
1573 		if (__read_pkey_reg() != new_pkru)
1574 			exit(1);
1575 
1576 		/* Stop and allow the tracer to clear XSTATE_BV for PKRU */
1577 		raise(SIGSTOP);
1578 
1579 		if (__read_pkey_reg() != 0)
1580 			exit(1);
1581 
1582 		/* Stop and allow the tracer to examine PKRU */
1583 		raise(SIGSTOP);
1584 
1585 		exit(0);
1586 	}
1587 
1588 	pkey_assert(child == waitpid(child, &status, 0));
1589 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1590 	pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
1591 
1592 	xsave = (void *)malloc(xsave_size);
1593 	pkey_assert(xsave > 0);
1594 
1595 	/* Modify the PKRU register directly */
1596 	iov.iov_base = xsave;
1597 	iov.iov_len = xsave_size;
1598 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1599 	pkey_assert(ret == 0);
1600 
1601 	pkey_register = (u32 *)(xsave + pkey_offset);
1602 	pkey_assert(*pkey_register == read_pkey_reg());
1603 
1604 	*pkey_register = new_pkru;
1605 
1606 	ret = ptrace(PTRACE_SETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1607 	pkey_assert(ret == 0);
1608 
1609 	/* Test that the modification is visible in ptrace before any execution */
1610 	memset(xsave, 0xCC, xsave_size);
1611 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1612 	pkey_assert(ret == 0);
1613 	pkey_assert(*pkey_register == new_pkru);
1614 
1615 	/* Execute the tracee */
1616 	ret = ptrace(PTRACE_CONT, child, 0, 0);
1617 	pkey_assert(ret == 0);
1618 
1619 	/* Test that the tracee saw the PKRU value change */
1620 	pkey_assert(child == waitpid(child, &status, 0));
1621 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1622 	pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
1623 
1624 	/* Test that the modification is visible in ptrace after execution */
1625 	memset(xsave, 0xCC, xsave_size);
1626 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1627 	pkey_assert(ret == 0);
1628 	pkey_assert(*pkey_register == new_pkru);
1629 
1630 	/* Clear the PKRU bit from XSTATE_BV */
1631 	xstate_bv = (u64 *)(xsave + 512);
1632 	*xstate_bv &= ~(1 << 9);
1633 
1634 	ret = ptrace(PTRACE_SETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1635 	pkey_assert(ret == 0);
1636 
1637 	/* Test that the modification is visible in ptrace before any execution */
1638 	memset(xsave, 0xCC, xsave_size);
1639 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1640 	pkey_assert(ret == 0);
1641 	pkey_assert(*pkey_register == 0);
1642 
1643 	ret = ptrace(PTRACE_CONT, child, 0, 0);
1644 	pkey_assert(ret == 0);
1645 
1646 	/* Test that the tracee saw the PKRU value go to 0 */
1647 	pkey_assert(child == waitpid(child, &status, 0));
1648 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1649 	pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
1650 
1651 	/* Test that the modification is visible in ptrace after execution */
1652 	memset(xsave, 0xCC, xsave_size);
1653 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_X86_XSTATE, &iov);
1654 	pkey_assert(ret == 0);
1655 	pkey_assert(*pkey_register == 0);
1656 
1657 	ret = ptrace(PTRACE_CONT, child, 0, 0);
1658 	pkey_assert(ret == 0);
1659 	pkey_assert(child == waitpid(child, &status, 0));
1660 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1661 	pkey_assert(WIFEXITED(status));
1662 	pkey_assert(WEXITSTATUS(status) == 0);
1663 	free(xsave);
1664 }
1665 #endif
1666 
1667 #if defined(__aarch64__)
test_ptrace_modifies_pkru(int * ptr,u16 pkey)1668 void test_ptrace_modifies_pkru(int *ptr, u16 pkey)
1669 {
1670 	pid_t child;
1671 	int status, ret;
1672 	struct iovec iov;
1673 	u64 trace_pkey;
1674 	/* Just a random pkey value.. */
1675 	u64 new_pkey = (POE_X << PKEY_BITS_PER_PKEY * 2) |
1676 			(POE_NONE << PKEY_BITS_PER_PKEY) |
1677 			POE_RWX;
1678 
1679 	child = fork();
1680 	pkey_assert(child >= 0);
1681 	dprintf3("[%d] fork() ret: %d\n", getpid(), child);
1682 	if (!child) {
1683 		ptrace(PTRACE_TRACEME, 0, 0, 0);
1684 
1685 		/* Stop and allow the tracer to modify PKRU directly */
1686 		raise(SIGSTOP);
1687 
1688 		/*
1689 		 * need __read_pkey_reg() version so we do not do shadow_pkey_reg
1690 		 * checking
1691 		 */
1692 		if (__read_pkey_reg() != new_pkey)
1693 			exit(1);
1694 
1695 		raise(SIGSTOP);
1696 
1697 		exit(0);
1698 	}
1699 
1700 	pkey_assert(child == waitpid(child, &status, 0));
1701 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1702 	pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
1703 
1704 	iov.iov_base = &trace_pkey;
1705 	iov.iov_len = 8;
1706 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_ARM_POE, &iov);
1707 	pkey_assert(ret == 0);
1708 	pkey_assert(trace_pkey == read_pkey_reg());
1709 
1710 	trace_pkey = new_pkey;
1711 
1712 	ret = ptrace(PTRACE_SETREGSET, child, (void *)NT_ARM_POE, &iov);
1713 	pkey_assert(ret == 0);
1714 
1715 	/* Test that the modification is visible in ptrace before any execution */
1716 	memset(&trace_pkey, 0, sizeof(trace_pkey));
1717 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_ARM_POE, &iov);
1718 	pkey_assert(ret == 0);
1719 	pkey_assert(trace_pkey == new_pkey);
1720 
1721 	/* Execute the tracee */
1722 	ret = ptrace(PTRACE_CONT, child, 0, 0);
1723 	pkey_assert(ret == 0);
1724 
1725 	/* Test that the tracee saw the PKRU value change */
1726 	pkey_assert(child == waitpid(child, &status, 0));
1727 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1728 	pkey_assert(WIFSTOPPED(status) && WSTOPSIG(status) == SIGSTOP);
1729 
1730 	/* Test that the modification is visible in ptrace after execution */
1731 	memset(&trace_pkey, 0, sizeof(trace_pkey));
1732 	ret = ptrace(PTRACE_GETREGSET, child, (void *)NT_ARM_POE, &iov);
1733 	pkey_assert(ret == 0);
1734 	pkey_assert(trace_pkey == new_pkey);
1735 
1736 	ret = ptrace(PTRACE_CONT, child, 0, 0);
1737 	pkey_assert(ret == 0);
1738 	pkey_assert(child == waitpid(child, &status, 0));
1739 	dprintf3("[%d] waitpid(%d) status: %x\n", getpid(), child, status);
1740 	pkey_assert(WIFEXITED(status));
1741 	pkey_assert(WEXITSTATUS(status) == 0);
1742 }
1743 #endif
1744 
test_mprotect_pkey_on_unsupported_cpu(int * ptr,u16 pkey)1745 void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
1746 {
1747 	int size = PAGE_SIZE;
1748 	int sret;
1749 
1750 	if (cpu_has_pkeys()) {
1751 		dprintf1("SKIP: %s: no CPU support\n", __func__);
1752 		return;
1753 	}
1754 
1755 	sret = syscall(__NR_pkey_mprotect, ptr, size, PROT_READ, pkey);
1756 	pkey_assert(sret < 0);
1757 }
1758 
1759 void (*pkey_tests[])(int *ptr, u16 pkey) = {
1760 	test_read_of_write_disabled_region,
1761 	test_read_of_access_disabled_region,
1762 	test_read_of_access_disabled_region_with_page_already_mapped,
1763 	test_write_of_write_disabled_region,
1764 	test_write_of_write_disabled_region_with_page_already_mapped,
1765 	test_write_of_access_disabled_region,
1766 	test_write_of_access_disabled_region_with_page_already_mapped,
1767 	test_kernel_write_of_access_disabled_region,
1768 	test_kernel_write_of_write_disabled_region,
1769 	test_kernel_gup_of_access_disabled_region,
1770 	test_kernel_gup_write_to_write_disabled_region,
1771 	test_executing_on_unreadable_memory,
1772 	test_implicit_mprotect_exec_only_memory,
1773 	test_mprotect_with_pkey_0,
1774 	test_ptrace_of_child,
1775 	test_pkey_init_state,
1776 	test_pkey_syscalls_on_non_allocated_pkey,
1777 	test_pkey_syscalls_bad_args,
1778 	test_pkey_alloc_exhaust,
1779 	test_pkey_alloc_free_attach_pkey0,
1780 #if defined(__i386__) || defined(__x86_64__) || defined(__aarch64__)
1781 	test_ptrace_modifies_pkru,
1782 #endif
1783 };
1784 
run_tests_once(void)1785 void run_tests_once(void)
1786 {
1787 	int *ptr;
1788 	int prot = PROT_READ|PROT_WRITE;
1789 
1790 	for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
1791 		int pkey;
1792 		int orig_pkey_faults = pkey_faults;
1793 
1794 		dprintf1("======================\n");
1795 		dprintf1("test %d preparing...\n", test_nr);
1796 
1797 		tracing_on();
1798 		pkey = alloc_random_pkey();
1799 		dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
1800 		ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
1801 		dprintf1("test %d starting...\n", test_nr);
1802 		pkey_tests[test_nr](ptr, pkey);
1803 		dprintf1("freeing test memory: %p\n", ptr);
1804 		free_pkey_malloc(ptr);
1805 		sys_pkey_free(pkey);
1806 
1807 		dprintf1("pkey_faults: %d\n", pkey_faults);
1808 		dprintf1("orig_pkey_faults: %d\n", orig_pkey_faults);
1809 
1810 		tracing_off();
1811 		close_test_fds();
1812 
1813 		printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
1814 		dprintf1("======================\n\n");
1815 	}
1816 	iteration_nr++;
1817 }
1818 
pkey_setup_shadow(void)1819 void pkey_setup_shadow(void)
1820 {
1821 	shadow_pkey_reg = __read_pkey_reg();
1822 }
1823 
main(void)1824 int main(void)
1825 {
1826 	int nr_iterations = 22;
1827 	int pkeys_supported = is_pkeys_supported();
1828 
1829 	srand((unsigned int)time(NULL));
1830 
1831 	setup_handlers();
1832 
1833 	printf("has pkeys: %d\n", pkeys_supported);
1834 
1835 	if (!pkeys_supported) {
1836 		int size = PAGE_SIZE;
1837 		int *ptr;
1838 
1839 		printf("running PKEY tests for unsupported CPU/OS\n");
1840 
1841 		ptr  = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
1842 		assert(ptr != (void *)-1);
1843 		test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
1844 		exit(0);
1845 	}
1846 
1847 	pkey_setup_shadow();
1848 	printf("startup pkey_reg: %016llx\n", read_pkey_reg());
1849 	setup_hugetlbfs();
1850 
1851 	while (nr_iterations-- > 0)
1852 		run_tests_once();
1853 
1854 	printf("done (all tests OK)\n");
1855 	return 0;
1856 }
1857