summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/x86/protection_keys.c
blob: bc1b0735bb50ed02963e834c7dc38395f7c6d834 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
// SPDX-License-Identifier: GPL-2.0
/*
 * Tests x86 Memory Protection Keys (see Documentation/x86/protection-keys.txt)
 *
 * There are examples in here of:
 *  * how to set protection keys on memory
 *  * how to set/clear bits in PKRU (the rights register)
 *  * how to handle SEGV_PKRU signals and extract pkey-relevant
 *    information from the siginfo
 *
 * Things to add:
 *	make sure KSM and KSM COW breaking works
 *	prefault pages in at malloc, or not
 *	protect MPX bounds tables with protection keys?
 *	make sure VMA splitting/merging is working correctly
 *	OOMs can destroy mm->mmap (see exit_mmap()), so make sure it is immune to pkeys
 *	look for pkey "leaks" where it is still set on a VMA but "freed" back to the kernel
 *	do a plain mprotect() to a mprotect_pkey() area and make sure the pkey sticks
 *
 * Compile like this:
 *	gcc      -o protection_keys    -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
 *	gcc -m32 -o protection_keys_32 -O2 -g -std=gnu99 -pthread -Wall protection_keys.c -lrt -ldl -lm
 */
#define _GNU_SOURCE
#include <errno.h>
#include <linux/futex.h>
#include <sys/time.h>
#include <sys/syscall.h>
#include <string.h>
#include <stdio.h>
#include <stdint.h>
#include <stdbool.h>
#include <signal.h>
#include <assert.h>
#include <stdlib.h>
#include <ucontext.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/ptrace.h>
#include <setjmp.h>

#include "pkey-helpers.h"

int iteration_nr = 1;
int test_nr;

unsigned int shadow_pkru;

#define HPAGE_SIZE	(1UL<<21)
#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
#define ALIGN_UP(x, align_to)	(((x) + ((align_to)-1)) & ~((align_to)-1))
#define ALIGN_DOWN(x, align_to) ((x) & ~((align_to)-1))
#define ALIGN_PTR_UP(p, ptr_align_to)	((typeof(p))ALIGN_UP((unsigned long)(p),	ptr_align_to))
#define ALIGN_PTR_DOWN(p, ptr_align_to)	((typeof(p))ALIGN_DOWN((unsigned long)(p),	ptr_align_to))
#define __stringify_1(x...)     #x
#define __stringify(x...)       __stringify_1(x)

#define PTR_ERR_ENOTSUP ((void *)-ENOTSUP)

int dprint_in_signal;
char dprint_in_signal_buffer[DPRINT_IN_SIGNAL_BUF_SIZE];

extern void abort_hooks(void);
#define pkey_assert(condition) do {		\
	if (!(condition)) {			\
		dprintf0("assert() at %s::%d test_nr: %d iteration: %d\n", \
				__FILE__, __LINE__,	\
				test_nr, iteration_nr);	\
		dprintf0("errno at assert: %d", errno);	\
		abort_hooks();			\
		assert(condition);		\
	}					\
} while (0)
#define raw_assert(cond) assert(cond)

void cat_into_file(char *str, char *file)
{
	int fd = open(file, O_RDWR);
	int ret;

	dprintf2("%s(): writing '%s' to '%s'\n", __func__, str, file);
	/*
	 * these need to be raw because they are called under
	 * pkey_assert()
	 */
	raw_assert(fd >= 0);
	ret = write(fd, str, strlen(str));
	if (ret != strlen(str)) {
		perror("write to file failed");
		fprintf(stderr, "filename: '%s' str: '%s'\n", file, str);
		raw_assert(0);
	}
	close(fd);
}

#if CONTROL_TRACING > 0
static int warned_tracing;
int tracing_root_ok(void)
{
	if (geteuid() != 0) {
		if (!warned_tracing)
			fprintf(stderr, "WARNING: not run as root, "
					"can not do tracing control\n");
		warned_tracing = 1;
		return 0;
	}
	return 1;
}
#endif

void tracing_on(void)
{
#if CONTROL_TRACING > 0
#define TRACEDIR "/sys/kernel/debug/tracing"
	char pidstr[32];

	if (!tracing_root_ok())
		return;

	sprintf(pidstr, "%d", getpid());
	cat_into_file("0", TRACEDIR "/tracing_on");
	cat_into_file("\n", TRACEDIR "/trace");
	if (1) {
		cat_into_file("function_graph", TRACEDIR "/current_tracer");
		cat_into_file("1", TRACEDIR "/options/funcgraph-proc");
	} else {
		cat_into_file("nop", TRACEDIR "/current_tracer");
	}
	cat_into_file(pidstr, TRACEDIR "/set_ftrace_pid");
	cat_into_file("1", TRACEDIR "/tracing_on");
	dprintf1("enabled tracing\n");
#endif
}

void tracing_off(void)
{
#if CONTROL_TRACING > 0
	if (!tracing_root_ok())
		return;
	cat_into_file("0", "/sys/kernel/debug/tracing/tracing_on");
#endif
}

void abort_hooks(void)
{
	fprintf(stderr, "running %s()...\n", __func__);
	tracing_off();
#ifdef SLEEP_ON_ABORT
	sleep(SLEEP_ON_ABORT);
#endif
}

static inline void __page_o_noops(void)
{
	/* 8-bytes of instruction * 512 bytes = 1 page */
	asm(".rept 512 ; nopl 0x7eeeeeee(%eax) ; .endr");
}

/*
 * This attempts to have roughly a page of instructions followed by a few
 * instructions that do a write, and another page of instructions.  That
 * way, we are pretty sure that the write is in the second page of
 * instructions and has at least a page of padding behind it.
 *
 * *That* lets us be sure to madvise() away the write instruction, which
 * will then fault, which makes sure that the fault code handles
 * execute-only memory properly.
 */
__attribute__((__aligned__(PAGE_SIZE)))
void lots_o_noops_around_write(int *write_to_me)
{
	dprintf3("running %s()\n", __func__);
	__page_o_noops();
	/* Assume this happens in the second page of instructions: */
	*write_to_me = __LINE__;
	/* pad out by another page: */
	__page_o_noops();
	dprintf3("%s() done\n", __func__);
}

/* Define some kernel-like types */
#define  u8 uint8_t
#define u16 uint16_t
#define u32 uint32_t
#define u64 uint64_t

#ifdef __i386__

#ifndef SYS_mprotect_key
# define SYS_mprotect_key 380
#endif
#ifndef SYS_pkey_alloc
# define SYS_pkey_alloc	 381
# define SYS_pkey_free	 382
#endif
#define REG_IP_IDX REG_EIP
#define si_pkey_offset 0x14

#else

#ifndef SYS_mprotect_key
# define SYS_mprotect_key 329
#endif
#ifndef SYS_pkey_alloc
# define SYS_pkey_alloc	 330
# define SYS_pkey_free	 331
#endif
#define REG_IP_IDX REG_RIP
#define si_pkey_offset 0x20

#endif

void dump_mem(void *dumpme, int len_bytes)
{
	char *c = (void *)dumpme;
	int i;

	for (i = 0; i < len_bytes; i += sizeof(u64)) {
		u64 *ptr = (u64 *)(c + i);
		dprintf1("dump[%03d][@%p]: %016jx\n", i, ptr, *ptr);
	}
}

#define SEGV_BNDERR     3  /* failed address bound checks */
#define SEGV_PKUERR     4

static char *si_code_str(int si_code)
{
	if (si_code == SEGV_MAPERR)
		return "SEGV_MAPERR";
	if (si_code == SEGV_ACCERR)
		return "SEGV_ACCERR";
	if (si_code == SEGV_BNDERR)
		return "SEGV_BNDERR";
	if (si_code == SEGV_PKUERR)
		return "SEGV_PKUERR";
	return "UNKNOWN";
}

int pkru_faults;
int last_si_pkey = -1;
void signal_handler(int signum, siginfo_t *si, void *vucontext)
{
	ucontext_t *uctxt = vucontext;
	int trapno;
	unsigned long ip;
	char *fpregs;
	u32 *pkru_ptr;
	u64 siginfo_pkey;
	u32 *si_pkey_ptr;
	int pkru_offset;
	fpregset_t fpregset;

	dprint_in_signal = 1;
	dprintf1(">>>>===============SIGSEGV============================\n");
	dprintf1("%s()::%d, pkru: 0x%x shadow: %x\n", __func__, __LINE__,
			__rdpkru(), shadow_pkru);

	trapno = uctxt->uc_mcontext.gregs[REG_TRAPNO];
	ip = uctxt->uc_mcontext.gregs[REG_IP_IDX];
	fpregset = uctxt->uc_mcontext.fpregs;
	fpregs = (void *)fpregset;

	dprintf2("%s() trapno: %d ip: 0x%lx info->si_code: %s/%d\n", __func__,
			trapno, ip, si_code_str(si->si_code), si->si_code);
#ifdef __i386__
	/*
	 * 32-bit has some extra padding so that userspace can tell whether
	 * the XSTATE header is present in addition to the "legacy" FPU
	 * state.  We just assume that it is here.
	 */
	fpregs += 0x70;
#endif
	pkru_offset = pkru_xstate_offset();
	pkru_ptr = (void *)(&fpregs[pkru_offset]);

	dprintf1("siginfo: %p\n", si);
	dprintf1(" fpregs: %p\n", fpregs);
	/*
	 * If we got a PKRU fault, we *HAVE* to have at least one bit set in
	 * here.
	 */
	dprintf1("pkru_xstate_offset: %d\n", pkru_xstate_offset());
	if (DEBUG_LEVEL > 4)
		dump_mem(pkru_ptr - 128, 256);
	pkey_assert(*pkru_ptr);

	si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
	dump_mem(si_pkey_ptr - 8, 24);
	siginfo_pkey = *si_pkey_ptr;
	pkey_assert(siginfo_pkey < NR_PKEYS);
	last_si_pkey = siginfo_pkey;

	if ((si->si_code == SEGV_MAPERR) ||
	    (si->si_code == SEGV_ACCERR) ||
	    (si->si_code == SEGV_BNDERR)) {
		printf("non-PK si_code, exiting...\n");
		exit(4);
	}

	dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
	/* need __rdpkru() version so we do not do shadow_pkru checking */
	dprintf1("signal pkru from  pkru: %08x\n", __rdpkru());
	dprintf1("pkey from siginfo: %jx\n", siginfo_pkey);
	*(u64 *)pkru_ptr = 0x00000000;
	dprintf1("WARNING: set PRKU=0 to allow faulting instruction to continue\n");
	pkru_faults++;
	dprintf1("<<<<==================================================\n");
	return;
	if (trapno == 14) {
		fprintf(stderr,
			"ERROR: In signal handler, page fault, trapno = %d, ip = %016lx\n",
			trapno, ip);
		fprintf(stderr, "si_addr %p\n", si->si_addr);
		fprintf(stderr, "REG_ERR: %lx\n",
				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
		exit(1);
	} else {
		fprintf(stderr, "unexpected trap %d! at 0x%lx\n", trapno, ip);
		fprintf(stderr, "si_addr %p\n", si->si_addr);
		fprintf(stderr, "REG_ERR: %lx\n",
				(unsigned long)uctxt->uc_mcontext.gregs[REG_ERR]);
		exit(2);
	}
	dprint_in_signal = 0;
}

int wait_all_children(void)
{
	int status;
	return waitpid(-1, &status, 0);
}

void sig_chld(int x)
{
	dprint_in_signal = 1;
	dprintf2("[%d] SIGCHLD: %d\n", getpid(), x);
	dprint_in_signal = 0;
}

void setup_sigsegv_handler(void)
{
	int r, rs;
	struct sigaction newact;
	struct sigaction oldact;

	/* #PF is mapped to sigsegv */
	int signum  = SIGSEGV;

	newact.sa_handler = 0;
	newact.sa_sigaction = signal_handler;

	/*sigset_t - signals to block while in the handler */
	/* get the old signal mask. */
	rs = sigprocmask(SIG_SETMASK, 0, &newact.sa_mask);
	pkey_assert(rs == 0);

	/* call sa_sigaction, not sa_handler*/
	newact.sa_flags = SA_SIGINFO;

	newact.sa_restorer = 0;  /* void(*)(), obsolete */
	r = sigaction(signum, &newact, &oldact);
	r = sigaction(SIGALRM, &newact, &oldact);
	pkey_assert(r == 0);
}

void setup_handlers(void)
{
	signal(SIGCHLD, &sig_chld);
	setup_sigsegv_handler();
}

pid_t fork_lazy_child(void)
{
	pid_t forkret;

	forkret = fork();
	pkey_assert(forkret >= 0);
	dprintf3("[%d] fork() ret: %d\n", getpid(), forkret);

	if (!forkret) {
		/* in the child */
		while (1) {
			dprintf1("child sleeping...\n");
			sleep(30);
		}
	}
	return forkret;
}

void davecmp(void *_a, void *_b, int len)
{
	int i;
	unsigned long *a = _a;
	unsigned long *b = _b;

	for (i = 0; i < len / sizeof(*a); i++) {
		if (a[i] == b[i])
			continue;

		dprintf3("[%3d]: a: %016lx b: %016lx\n", i, a[i], b[i]);
	}
}

void dumpit(char *f)
{
	int fd = open(f, O_RDONLY);
	char buf[100];
	int nr_read;

	dprintf2("maps fd: %d\n", fd);
	do {
		nr_read = read(fd, &buf[0], sizeof(buf));
		write(1, buf, nr_read);
	} while (nr_read > 0);
	close(fd);
}

#define PKEY_DISABLE_ACCESS    0x1
#define PKEY_DISABLE_WRITE     0x2

u32 pkey_get(int pkey, unsigned long flags)
{
	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
	u32 pkru = __rdpkru();
	u32 shifted_pkru;
	u32 masked_pkru;

	dprintf1("%s(pkey=%d, flags=%lx) = %x / %d\n",
			__func__, pkey, flags, 0, 0);
	dprintf2("%s() raw pkru: %x\n", __func__, pkru);

	shifted_pkru = (pkru >> (pkey * PKRU_BITS_PER_PKEY));
	dprintf2("%s() shifted_pkru: %x\n", __func__, shifted_pkru);
	masked_pkru = shifted_pkru & mask;
	dprintf2("%s() masked  pkru: %x\n", __func__, masked_pkru);
	/*
	 * shift down the relevant bits to the lowest two, then
	 * mask off all the other high bits.
	 */
	return masked_pkru;
}

int pkey_set(int pkey, unsigned long rights, unsigned long flags)
{
	u32 mask = (PKEY_DISABLE_ACCESS|PKEY_DISABLE_WRITE);
	u32 old_pkru = __rdpkru();
	u32 new_pkru;

	/* make sure that 'rights' only contains the bits we expect: */
	assert(!(rights & ~mask));

	/* copy old pkru */
	new_pkru = old_pkru;
	/* mask out bits from pkey in old value: */
	new_pkru &= ~(mask << (pkey * PKRU_BITS_PER_PKEY));
	/* OR in new bits for pkey: */
	new_pkru |= (rights << (pkey * PKRU_BITS_PER_PKEY));

	__wrpkru(new_pkru);

	dprintf3("%s(pkey=%d, rights=%lx, flags=%lx) = %x pkru now: %x old_pkru: %x\n",
			__func__, pkey, rights, flags, 0, __rdpkru(), old_pkru);
	return 0;
}

void pkey_disable_set(int pkey, int flags)
{
	unsigned long syscall_flags = 0;
	int ret;
	int pkey_rights;
	u32 orig_pkru = rdpkru();

	dprintf1("START->%s(%d, 0x%x)\n", __func__,
		pkey, flags);
	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));

	pkey_rights = pkey_get(pkey, syscall_flags);

	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
			pkey, pkey, pkey_rights);
	pkey_assert(pkey_rights >= 0);

	pkey_rights |= flags;

	ret = pkey_set(pkey, pkey_rights, syscall_flags);
	assert(!ret);
	/*pkru and flags have the same format */
	shadow_pkru |= flags << (pkey * 2);
	dprintf1("%s(%d) shadow: 0x%x\n", __func__, pkey, shadow_pkru);

	pkey_assert(ret >= 0);

	pkey_rights = pkey_get(pkey, syscall_flags);
	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
			pkey, pkey, pkey_rights);

	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
	if (flags)
		pkey_assert(rdpkru() > orig_pkru);
	dprintf1("END<---%s(%d, 0x%x)\n", __func__,
		pkey, flags);
}

void pkey_disable_clear(int pkey, int flags)
{
	unsigned long syscall_flags = 0;
	int ret;
	int pkey_rights = pkey_get(pkey, syscall_flags);
	u32 orig_pkru = rdpkru();

	pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));

	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
			pkey, pkey, pkey_rights);
	pkey_assert(pkey_rights >= 0);

	pkey_rights |= flags;

	ret = pkey_set(pkey, pkey_rights, 0);
	/* pkru and flags have the same format */
	shadow_pkru &= ~(flags << (pkey * 2));
	pkey_assert(ret >= 0);

	pkey_rights = pkey_get(pkey, syscall_flags);
	dprintf1("%s(%d) pkey_get(%d): %x\n", __func__,
			pkey, pkey, pkey_rights);

	dprintf1("%s(%d) pkru: 0x%x\n", __func__, pkey, rdpkru());
	if (flags)
		assert(rdpkru() > orig_pkru);
}

void pkey_write_allow(int pkey)
{
	pkey_disable_clear(pkey, PKEY_DISABLE_WRITE);
}
void pkey_write_deny(int pkey)
{
	pkey_disable_set(pkey, PKEY_DISABLE_WRITE);
}
void pkey_access_allow(int pkey)
{
	pkey_disable_clear(pkey, PKEY_DISABLE_ACCESS);
}
void pkey_access_deny(int pkey)
{
	pkey_disable_set(pkey, PKEY_DISABLE_ACCESS);
}

int sys_mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
		unsigned long pkey)
{
	int sret;

	dprintf2("%s(0x%p, %zx, prot=%lx, pkey=%lx)\n", __func__,
			ptr, size, orig_prot, pkey);

	errno = 0;
	sret = syscall(SYS_mprotect_key, ptr, size, orig_prot, pkey);
	if (errno) {
		dprintf2("SYS_mprotect_key sret: %d\n", sret);
		dprintf2("SYS_mprotect_key prot: 0x%lx\n", orig_prot);
		dprintf2("SYS_mprotect_key failed, errno: %d\n", errno);
		if (DEBUG_LEVEL >= 2)
			perror("SYS_mprotect_pkey");
	}
	return sret;
}

int sys_pkey_alloc(unsigned long flags, unsigned long init_val)
{
	int ret = syscall(SYS_pkey_alloc, flags, init_val);
	dprintf1("%s(flags=%lx, init_val=%lx) syscall ret: %d errno: %d\n",
			__func__, flags, init_val, ret, errno);
	return ret;
}

int alloc_pkey(void)
{
	int ret;
	unsigned long init_val = 0x0;

	dprintf1("alloc_pkey()::%d, pkru: 0x%x shadow: %x\n",
			__LINE__, __rdpkru(), shadow_pkru);
	ret = sys_pkey_alloc(0, init_val);
	/*
	 * pkey_alloc() sets PKRU, so we need to reflect it in
	 * shadow_pkru:
	 */
	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
			__LINE__, ret, __rdpkru(), shadow_pkru);
	if (ret) {
		/* clear both the bits: */
		shadow_pkru &= ~(0x3      << (ret * 2));
		dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
				__LINE__, ret, __rdpkru(), shadow_pkru);
		/*
		 * move the new state in from init_val
		 * (remember, we cheated and init_val == pkru format)
		 */
		shadow_pkru |=  (init_val << (ret * 2));
	}
	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
			__LINE__, ret, __rdpkru(), shadow_pkru);
	dprintf1("alloc_pkey()::%d errno: %d\n", __LINE__, errno);
	/* for shadow checking: */
	rdpkru();
	dprintf4("alloc_pkey()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n",
			__LINE__, ret, __rdpkru(), shadow_pkru);
	return ret;
}

int sys_pkey_free(unsigned long pkey)
{
	int ret = syscall(SYS_pkey_free, pkey);
	dprintf1("%s(pkey=%ld) syscall ret: %d\n", __func__, pkey, ret);
	return ret;
}

/*
 * I had a bug where pkey bits could be set by mprotect() but
 * not cleared.  This ensures we get lots of random bit sets
 * and clears on the vma and pte pkey bits.
 */
int alloc_random_pkey(void)
{
	int max_nr_pkey_allocs;
	int ret;
	int i;
	int alloced_pkeys[NR_PKEYS];
	int nr_alloced = 0;
	int random_index;
	memset(alloced_pkeys, 0, sizeof(alloced_pkeys));

	/* allocate every possible key and make a note of which ones we got */
	max_nr_pkey_allocs = NR_PKEYS;
	max_nr_pkey_allocs = 1;
	for (i = 0; i < max_nr_pkey_allocs; i++) {
		int new_pkey = alloc_pkey();
		if (new_pkey < 0)
			break;
		alloced_pkeys[nr_alloced++] = new_pkey;
	}

	pkey_assert(nr_alloced > 0);
	/* select a random one out of the allocated ones */
	random_index = rand() % nr_alloced;
	ret = alloced_pkeys[random_index];
	/* now zero it out so we don't free it next */
	alloced_pkeys[random_index] = 0;

	/* go through the allocated ones that we did not want and free them */
	for (i = 0; i < nr_alloced; i++) {
		int free_ret;
		if (!alloced_pkeys[i])
			continue;
		free_ret = sys_pkey_free(alloced_pkeys[i]);
		pkey_assert(!free_ret);
	}
	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
			__LINE__, ret, __rdpkru(), shadow_pkru);
	return ret;
}

int mprotect_pkey(void *ptr, size_t size, unsigned long orig_prot,
		unsigned long pkey)
{
	int nr_iterations = random() % 100;
	int ret;

	while (0) {
		int rpkey = alloc_random_pkey();
		ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
		dprintf1("sys_mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
				ptr, size, orig_prot, pkey, ret);
		if (nr_iterations-- < 0)
			break;

		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
			__LINE__, ret, __rdpkru(), shadow_pkru);
		sys_pkey_free(rpkey);
		dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
			__LINE__, ret, __rdpkru(), shadow_pkru);
	}
	pkey_assert(pkey < NR_PKEYS);

	ret = sys_mprotect_pkey(ptr, size, orig_prot, pkey);
	dprintf1("mprotect_pkey(%p, %zx, prot=0x%lx, pkey=%ld) ret: %d\n",
			ptr, size, orig_prot, pkey, ret);
	pkey_assert(!ret);
	dprintf1("%s()::%d, ret: %d pkru: 0x%x shadow: 0x%x\n", __func__,
			__LINE__, ret, __rdpkru(), shadow_pkru);
	return ret;
}

struct pkey_malloc_record {
	void *ptr;
	long size;
};
struct pkey_malloc_record *pkey_malloc_records;
long nr_pkey_malloc_records;
void record_pkey_malloc(void *ptr, long size)
{
	long i;
	struct pkey_malloc_record *rec = NULL;

	for (i = 0; i < nr_pkey_malloc_records; i++) {
		rec = &pkey_malloc_records[i];
		/* find a free record */
		if (rec)
			break;
	}
	if (!rec) {
		/* every record is full */
		size_t old_nr_records = nr_pkey_malloc_records;
		size_t new_nr_records = (nr_pkey_malloc_records * 2 + 1);
		size_t new_size = new_nr_records * sizeof(struct pkey_malloc_record);
		dprintf2("new_nr_records: %zd\n", new_nr_records);
		dprintf2("new_size: %zd\n", new_size);
		pkey_malloc_records = realloc(pkey_malloc_records, new_size);
		pkey_assert(pkey_malloc_records != NULL);
		rec = &pkey_malloc_records[nr_pkey_malloc_records];
		/*
		 * realloc() does not initialize memory, so zero it from
		 * the first new record all the way to the end.
		 */
		for (i = 0; i < new_nr_records - old_nr_records; i++)
			memset(rec + i, 0, sizeof(*rec));
	}
	dprintf3("filling malloc record[%d/%p]: {%p, %ld}\n",
		(int)(rec - pkey_malloc_records), rec, ptr, size);
	rec->ptr = ptr;
	rec->size = size;
	nr_pkey_malloc_records++;
}

void free_pkey_malloc(void *ptr)
{
	long i;
	int ret;
	dprintf3("%s(%p)\n", __func__, ptr);
	for (i = 0; i < nr_pkey_malloc_records; i++) {
		struct pkey_malloc_record *rec = &pkey_malloc_records[i];
		dprintf4("looking for ptr %p at record[%ld/%p]: {%p, %ld}\n",
				ptr, i, rec, rec->ptr, rec->size);
		if ((ptr <  rec->ptr) ||
		    (ptr >= rec->ptr + rec->size))
			continue;

		dprintf3("found ptr %p at record[%ld/%p]: {%p, %ld}\n",
				ptr, i, rec, rec->ptr, rec->size);
		nr_pkey_malloc_records--;
		ret = munmap(rec->ptr, rec->size);
		dprintf3("munmap ret: %d\n", ret);
		pkey_assert(!ret);
		dprintf3("clearing rec->ptr, rec: %p\n", rec);
		rec->ptr = NULL;
		dprintf3("done clearing rec->ptr, rec: %p\n", rec);
		return;
	}
	pkey_assert(false);
}


void *malloc_pkey_with_mprotect(long size, int prot, u16 pkey)
{
	void *ptr;
	int ret;

	rdpkru();
	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
			size, prot, pkey);
	pkey_assert(pkey < NR_PKEYS);
	ptr = mmap(NULL, size, prot, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
	pkey_assert(ptr != (void *)-1);
	ret = mprotect_pkey((void *)ptr, PAGE_SIZE, prot, pkey);
	pkey_assert(!ret);
	record_pkey_malloc(ptr, size);
	rdpkru();

	dprintf1("%s() for pkey %d @ %p\n", __func__, pkey, ptr);
	return ptr;
}

void *malloc_pkey_anon_huge(long size, int prot, u16 pkey)
{
	int ret;
	void *ptr;

	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
			size, prot, pkey);
	/*
	 * Guarantee we can fit at least one huge page in the resulting
	 * allocation by allocating space for 2:
	 */
	size = ALIGN_UP(size, HPAGE_SIZE * 2);
	ptr = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
	pkey_assert(ptr != (void *)-1);
	record_pkey_malloc(ptr, size);
	mprotect_pkey(ptr, size, prot, pkey);

	dprintf1("unaligned ptr: %p\n", ptr);
	ptr = ALIGN_PTR_UP(ptr, HPAGE_SIZE);
	dprintf1("  aligned ptr: %p\n", ptr);
	ret = madvise(ptr, HPAGE_SIZE, MADV_HUGEPAGE);
	dprintf1("MADV_HUGEPAGE ret: %d\n", ret);
	ret = madvise(ptr, HPAGE_SIZE, MADV_WILLNEED);
	dprintf1("MADV_WILLNEED ret: %d\n", ret);
	memset(ptr, 0, HPAGE_SIZE);

	dprintf1("mmap()'d thp for pkey %d @ %p\n", pkey, ptr);
	return ptr;
}

int hugetlb_setup_ok;
#define GET_NR_HUGE_PAGES 10
void setup_hugetlbfs(void)
{
	int err;
	int fd;
	char buf[] = "123";

	if (geteuid() != 0) {
		fprintf(stderr, "WARNING: not run as root, can not do hugetlb test\n");
		return;
	}

	cat_into_file(__stringify(GET_NR_HUGE_PAGES), "/proc/sys/vm/nr_hugepages");

	/*
	 * Now go make sure that we got the pages and that they
	 * are 2M pages.  Someone might have made 1G the default.
	 */
	fd = open("/sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages", O_RDONLY);
	if (fd < 0) {
		perror("opening sysfs 2M hugetlb config");
		return;
	}

	/* -1 to guarantee leaving the trailing \0 */
	err = read(fd, buf, sizeof(buf)-1);
	close(fd);
	if (err <= 0) {
		perror("reading sysfs 2M hugetlb config");
		return;
	}

	if (atoi(buf) != GET_NR_HUGE_PAGES) {
		fprintf(stderr, "could not confirm 2M pages, got: '%s' expected %d\n",
			buf, GET_NR_HUGE_PAGES);
		return;
	}

	hugetlb_setup_ok = 1;
}

void *malloc_pkey_hugetlb(long size, int prot, u16 pkey)
{
	void *ptr;
	int flags = MAP_ANONYMOUS|MAP_PRIVATE|MAP_HUGETLB;

	if (!hugetlb_setup_ok)
		return PTR_ERR_ENOTSUP;

	dprintf1("doing %s(%ld, %x, %x)\n", __func__, size, prot, pkey);
	size = ALIGN_UP(size, HPAGE_SIZE * 2);
	pkey_assert(pkey < NR_PKEYS);
	ptr = mmap(NULL, size, PROT_NONE, flags, -1, 0);
	pkey_assert(ptr != (void *)-1);
	mprotect_pkey(ptr, size, prot, pkey);

	record_pkey_malloc(ptr, size);

	dprintf1("mmap()'d hugetlbfs for pkey %d @ %p\n", pkey, ptr);
	return ptr;
}

void *malloc_pkey_mmap_dax(long size, int prot, u16 pkey)
{
	void *ptr;
	int fd;

	dprintf1("doing %s(size=%ld, prot=0x%x, pkey=%d)\n", __func__,
			size, prot, pkey);
	pkey_assert(pkey < NR_PKEYS);
	fd = open("/dax/foo", O_RDWR);
	pkey_assert(fd >= 0);

	ptr = mmap(0, size, prot, MAP_SHARED, fd, 0);
	pkey_assert(ptr != (void *)-1);

	mprotect_pkey(ptr, size, prot, pkey);

	record_pkey_malloc(ptr, size);

	dprintf1("mmap()'d for pkey %d @ %p\n", pkey, ptr);
	close(fd);
	return ptr;
}

void *(*pkey_malloc[])(long size, int prot, u16 pkey) = {

	malloc_pkey_with_mprotect,
	malloc_pkey_anon_huge,
	malloc_pkey_hugetlb
/* can not do direct with the pkey_mprotect() API:
	malloc_pkey_mmap_direct,
	malloc_pkey_mmap_dax,
*/
};

void *malloc_pkey(long size, int prot, u16 pkey)
{
	void *ret;
	static int malloc_type;
	int nr_malloc_types = ARRAY_SIZE(pkey_malloc);

	pkey_assert(pkey < NR_PKEYS);

	while (1) {
		pkey_assert(malloc_type < nr_malloc_types);

		ret = pkey_malloc[malloc_type](size, prot, pkey);
		pkey_assert(ret != (void *)-1);

		malloc_type++;
		if (malloc_type >= nr_malloc_types)
			malloc_type = (random()%nr_malloc_types);

		/* try again if the malloc_type we tried is unsupported */
		if (ret == PTR_ERR_ENOTSUP)
			continue;

		break;
	}

	dprintf3("%s(%ld, prot=%x, pkey=%x) returning: %p\n", __func__,
			size, prot, pkey, ret);
	return ret;
}

int last_pkru_faults;
void expected_pk_fault(int pkey)
{
	dprintf2("%s(): last_pkru_faults: %d pkru_faults: %d\n",
			__func__, last_pkru_faults, pkru_faults);
	dprintf2("%s(%d): last_si_pkey: %d\n", __func__, pkey, last_si_pkey);
	pkey_assert(last_pkru_faults + 1 == pkru_faults);
	pkey_assert(last_si_pkey == pkey);
	/*
	 * The signal handler shold have cleared out PKRU to let the
	 * test program continue.  We now have to restore it.
	 */
	if (__rdpkru() != 0)
		pkey_assert(0);

	__wrpkru(shadow_pkru);
	dprintf1("%s() set PKRU=%x to restore state after signal nuked it\n",
			__func__, shadow_pkru);
	last_pkru_faults = pkru_faults;
	last_si_pkey = -1;
}

void do_not_expect_pk_fault(void)
{
	pkey_assert(last_pkru_faults == pkru_faults);
}

int test_fds[10] = { -1 };
int nr_test_fds;
void __save_test_fd(int fd)
{
	pkey_assert(fd >= 0);
	pkey_assert(nr_test_fds < ARRAY_SIZE(test_fds));
	test_fds[nr_test_fds] = fd;
	nr_test_fds++;
}

int get_test_read_fd(void)
{
	int test_fd = open("/etc/passwd", O_RDONLY);
	__save_test_fd(test_fd);
	return test_fd;
}

void close_test_fds(void)
{
	int i;

	for (i = 0; i < nr_test_fds; i++) {
		if (test_fds[i] < 0)
			continue;
		close(test_fds[i]);
		test_fds[i] = -1;
	}
	nr_test_fds = 0;
}

#define barrier() __asm__ __volatile__("": : :"memory")
__attribute__((noinline)) int read_ptr(int *ptr)
{
	/*
	 * Keep GCC from optimizing this away somehow
	 */
	barrier();
	return *ptr;
}

void test_read_of_write_disabled_region(int *ptr, u16 pkey)
{
	int ptr_contents;

	dprintf1("disabling write access to PKEY[1], doing read\n");
	pkey_write_deny(pkey);
	ptr_contents = read_ptr(ptr);
	dprintf1("*ptr: %d\n", ptr_contents);
	dprintf1("\n");
}
void test_read_of_access_disabled_region(int *ptr, u16 pkey)
{
	int ptr_contents;

	dprintf1("disabling access to PKEY[%02d], doing read @ %p\n", pkey, ptr);
	rdpkru();
	pkey_access_deny(pkey);
	ptr_contents = read_ptr(ptr);
	dprintf1("*ptr: %d\n", ptr_contents);
	expected_pk_fault(pkey);
}
void test_write_of_write_disabled_region(int *ptr, u16 pkey)
{
	dprintf1("disabling write access to PKEY[%02d], doing write\n", pkey);
	pkey_write_deny(pkey);
	*ptr = __LINE__;
	expected_pk_fault(pkey);
}
void test_write_of_access_disabled_region(int *ptr, u16 pkey)
{
	dprintf1("disabling access to PKEY[%02d], doing write\n", pkey);
	pkey_access_deny(pkey);
	*ptr = __LINE__;
	expected_pk_fault(pkey);
}
void test_kernel_write_of_access_disabled_region(int *ptr, u16 pkey)
{
	int ret;
	int test_fd = get_test_read_fd();

	dprintf1("disabling access to PKEY[%02d], "
		 "having kernel read() to buffer\n", pkey);
	pkey_access_deny(pkey);
	ret = read(test_fd, ptr, 1);
	dprintf1("read ret: %d\n", ret);
	pkey_assert(ret);
}
void test_kernel_write_of_write_disabled_region(int *ptr, u16 pkey)
{
	int ret;
	int test_fd = get_test_read_fd();

	pkey_write_deny(pkey);
	ret = read(test_fd, ptr, 100);
	dprintf1("read ret: %d\n", ret);
	if (ret < 0 && (DEBUG_LEVEL > 0))
		perror("verbose read result (OK for this to be bad)");
	pkey_assert(ret);
}

void test_kernel_gup_of_access_disabled_region(int *ptr, u16 pkey)
{
	int pipe_ret, vmsplice_ret;
	struct iovec iov;
	int pipe_fds[2];

	pipe_ret = pipe(pipe_fds);

	pkey_assert(pipe_ret == 0);
	dprintf1("disabling access to PKEY[%02d], "
		 "having kernel vmsplice from buffer\n", pkey);
	pkey_access_deny(pkey);
	iov.iov_base = ptr;
	iov.iov_len = PAGE_SIZE;
	vmsplice_ret = vmsplice(pipe_fds[1], &iov, 1, SPLICE_F_GIFT);
	dprintf1("vmsplice() ret: %d\n", vmsplice_ret);
	pkey_assert(vmsplice_ret == -1);

	close(pipe_fds[0]);
	close(pipe_fds[1]);
}

void test_kernel_gup_write_to_write_disabled_region(int *ptr, u16 pkey)
{
	int ignored = 0xdada;
	int futex_ret;
	int some_int = __LINE__;

	dprintf1("disabling write to PKEY[%02d], "
		 "doing futex gunk in buffer\n", pkey);
	*ptr = some_int;
	pkey_write_deny(pkey);
	futex_ret = syscall(SYS_futex, ptr, FUTEX_WAIT, some_int-1, NULL,
			&ignored, ignored);
	if (DEBUG_LEVEL > 0)
		perror("futex");
	dprintf1("futex() ret: %d\n", futex_ret);
}

/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_syscalls_on_non_allocated_pkey(int *ptr, u16 pkey)
{
	int err;
	int i;

	/* Note: 0 is the default pkey, so don't mess with it */
	for (i = 1; i < NR_PKEYS; i++) {
		if (pkey == i)
			continue;

		dprintf1("trying get/set/free to non-allocated pkey: %2d\n", i);
		err = sys_pkey_free(i);
		pkey_assert(err);

		err = sys_pkey_free(i);
		pkey_assert(err);

		err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, i);
		pkey_assert(err);
	}
}

/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_syscalls_bad_args(int *ptr, u16 pkey)
{
	int err;
	int bad_pkey = NR_PKEYS+99;

	/* pass a known-invalid pkey in: */
	err = sys_mprotect_pkey(ptr, PAGE_SIZE, PROT_READ, bad_pkey);
	pkey_assert(err);
}

/* Assumes that all pkeys other than 'pkey' are unallocated */
void test_pkey_alloc_exhaust(int *ptr, u16 pkey)
{
	int err;
	int allocated_pkeys[NR_PKEYS] = {0};
	int nr_allocated_pkeys = 0;
	int i;

	for (i = 0; i < NR_PKEYS*2; i++) {
		int new_pkey;
		dprintf1("%s() alloc loop: %d\n", __func__, i);
		new_pkey = alloc_pkey();
		dprintf4("%s()::%d, err: %d pkru: 0x%x shadow: 0x%x\n", __func__,
				__LINE__, err, __rdpkru(), shadow_pkru);
		rdpkru(); /* for shadow checking */
		dprintf2("%s() errno: %d ENOSPC: %d\n", __func__, errno, ENOSPC);
		if ((new_pkey == -1) && (errno == ENOSPC)) {
			dprintf2("%s() failed to allocate pkey after %d tries\n",
				__func__, nr_allocated_pkeys);
			break;
		}
		pkey_assert(nr_allocated_pkeys < NR_PKEYS);
		allocated_pkeys[nr_allocated_pkeys++] = new_pkey;
	}

	dprintf3("%s()::%d\n", __func__, __LINE__);

	/*
	 * ensure it did not reach the end of the loop without
	 * failure:
	 */
	pkey_assert(i < NR_PKEYS*2);

	/*
	 * There are 16 pkeys supported in hardware.  One is taken
	 * up for the default (0) and another can be taken up by
	 * an execute-only mapping.  Ensure that we can allocate
	 * at least 14 (16-2).
	 */
	pkey_assert(i >= NR_PKEYS-2);

	for (i = 0; i < nr_allocated_pkeys; i++) {
		err = sys_pkey_free(allocated_pkeys[i]);
		pkey_assert(!err);
		rdpkru(); /* for shadow checking */
	}
}

void test_ptrace_of_child(int *ptr, u16 pkey)
{
	__attribute__((__unused__)) int peek_result;
	pid_t child_pid;
	void *ignored = 0;
	long ret;
	int status;
	/*
	 * This is the "control" for our little expermient.  Make sure
	 * we can always access it when ptracing.
	 */
	int *plain_ptr_unaligned = malloc(HPAGE_SIZE);
	int *plain_ptr = ALIGN_PTR_UP(plain_ptr_unaligned, PAGE_SIZE);

	/*
	 * Fork a child which is an exact copy of this process, of course.
	 * That means we can do all of our tests via ptrace() and then plain
	 * memory access and ensure they work differently.
	 */
	child_pid = fork_lazy_child();
	dprintf1("[%d] child pid: %d\n", getpid(), child_pid);

	ret = ptrace(PTRACE_ATTACH, child_pid, ignored, ignored);
	if (ret)
		perror("attach");
	dprintf1("[%d] attach ret: %ld %d\n", getpid(), ret, __LINE__);
	pkey_assert(ret != -1);
	ret = waitpid(child_pid, &status, WUNTRACED);
	if ((ret != child_pid) || !(WIFSTOPPED(status))) {
		fprintf(stderr, "weird waitpid result %ld stat %x\n",
				ret, status);
		pkey_assert(0);
	}
	dprintf2("waitpid ret: %ld\n", ret);
	dprintf2("waitpid status: %d\n", status);

	pkey_access_deny(pkey);
	pkey_write_deny(pkey);

	/* Write access, untested for now:
	ret = ptrace(PTRACE_POKEDATA, child_pid, peek_at, data);
	pkey_assert(ret != -1);
	dprintf1("poke at %p: %ld\n", peek_at, ret);
	*/

	/*
	 * Try to access the pkey-protected "ptr" via ptrace:
	 */
	ret = ptrace(PTRACE_PEEKDATA, child_pid, ptr, ignored);
	/* expect it to work, without an error: */
	pkey_assert(ret != -1);
	/* Now access from the current task, and expect an exception: */
	peek_result = read_ptr(ptr);
	expected_pk_fault(pkey);

	/*
	 * Try to access the NON-pkey-protected "plain_ptr" via ptrace:
	 */
	ret = ptrace(PTRACE_PEEKDATA, child_pid, plain_ptr, ignored);
	/* expect it to work, without an error: */
	pkey_assert(ret != -1);
	/* Now access from the current task, and expect NO exception: */
	peek_result = read_ptr(plain_ptr);
	do_not_expect_pk_fault();

	ret = ptrace(PTRACE_DETACH, child_pid, ignored, 0);
	pkey_assert(ret != -1);

	ret = kill(child_pid, SIGKILL);
	pkey_assert(ret != -1);

	wait(&status);

	free(plain_ptr_unaligned);
}

void test_executing_on_unreadable_memory(int *ptr, u16 pkey)
{
	void *p1;
	int scratch;
	int ptr_contents;
	int ret;

	p1 = ALIGN_PTR_UP(&lots_o_noops_around_write, PAGE_SIZE);
	dprintf3("&lots_o_noops: %p\n", &lots_o_noops_around_write);
	/* lots_o_noops_around_write should be page-aligned already */
	assert(p1 == &lots_o_noops_around_write);

	/* Point 'p1' at the *second* page of the function: */
	p1 += PAGE_SIZE;

	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
	lots_o_noops_around_write(&scratch);
	ptr_contents = read_ptr(p1);
	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);

	ret = mprotect_pkey(p1, PAGE_SIZE, PROT_EXEC, (u64)pkey);
	pkey_assert(!ret);
	pkey_access_deny(pkey);

	dprintf2("pkru: %x\n", rdpkru());

	/*
	 * Make sure this is an *instruction* fault
	 */
	madvise(p1, PAGE_SIZE, MADV_DONTNEED);
	lots_o_noops_around_write(&scratch);
	do_not_expect_pk_fault();
	ptr_contents = read_ptr(p1);
	dprintf2("ptr (%p) contents@%d: %x\n", p1, __LINE__, ptr_contents);
	expected_pk_fault(pkey);
}

void test_mprotect_pkey_on_unsupported_cpu(int *ptr, u16 pkey)
{
	int size = PAGE_SIZE;
	int sret;

	if (cpu_has_pku()) {
		dprintf1("SKIP: %s: no CPU support\n", __func__);
		return;
	}

	sret = syscall(SYS_mprotect_key, ptr, size, PROT_READ, pkey);
	pkey_assert(sret < 0);
}

void (*pkey_tests[])(int *ptr, u16 pkey) = {
	test_read_of_write_disabled_region,
	test_read_of_access_disabled_region,
	test_write_of_write_disabled_region,
	test_write_of_access_disabled_region,
	test_kernel_write_of_access_disabled_region,
	test_kernel_write_of_write_disabled_region,
	test_kernel_gup_of_access_disabled_region,
	test_kernel_gup_write_to_write_disabled_region,
	test_executing_on_unreadable_memory,
	test_ptrace_of_child,
	test_pkey_syscalls_on_non_allocated_pkey,
	test_pkey_syscalls_bad_args,
	test_pkey_alloc_exhaust,
};

void run_tests_once(void)
{
	int *ptr;
	int prot = PROT_READ|PROT_WRITE;

	for (test_nr = 0; test_nr < ARRAY_SIZE(pkey_tests); test_nr++) {
		int pkey;
		int orig_pkru_faults = pkru_faults;

		dprintf1("======================\n");
		dprintf1("test %d preparing...\n", test_nr);

		tracing_on();
		pkey = alloc_random_pkey();
		dprintf1("test %d starting with pkey: %d\n", test_nr, pkey);
		ptr = malloc_pkey(PAGE_SIZE, prot, pkey);
		dprintf1("test %d starting...\n", test_nr);
		pkey_tests[test_nr](ptr, pkey);
		dprintf1("freeing test memory: %p\n", ptr);
		free_pkey_malloc(ptr);
		sys_pkey_free(pkey);

		dprintf1("pkru_faults: %d\n", pkru_faults);
		dprintf1("orig_pkru_faults: %d\n", orig_pkru_faults);

		tracing_off();
		close_test_fds();

		printf("test %2d PASSED (iteration %d)\n", test_nr, iteration_nr);
		dprintf1("======================\n\n");
	}
	iteration_nr++;
}

void pkey_setup_shadow(void)
{
	shadow_pkru = __rdpkru();
}

int main(void)
{
	int nr_iterations = 22;

	setup_handlers();

	printf("has pku: %d\n", cpu_has_pku());

	if (!cpu_has_pku()) {
		int size = PAGE_SIZE;
		int *ptr;

		printf("running PKEY tests for unsupported CPU/OS\n");

		ptr  = mmap(NULL, size, PROT_NONE, MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
		assert(ptr != (void *)-1);
		test_mprotect_pkey_on_unsupported_cpu(ptr, 1);
		exit(0);
	}

	pkey_setup_shadow();
	printf("startup pkru: %x\n", rdpkru());
	setup_hugetlbfs();

	while (nr_iterations-- > 0)
		run_tests_once();

	printf("done (all tests OK)\n");
	return 0;
}