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Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski...
[linux-2.6-block.git] / tools / testing / selftests / x86 / ldt_gdt.c
CommitLineData
014dc90b
AL		 1/*
2 * ldt_gdt.c - Test cases for LDT and GDT access
3 * Copyright (c) 2015 Andrew Lutomirski
4 */
5
6#define _GNU_SOURCE
7#include <err.h>
8#include <stdio.h>
9#include <stdint.h>
10#include <signal.h>
11#include <setjmp.h>
12#include <stdlib.h>
13#include <string.h>
14#include <errno.h>
15#include <unistd.h>
16#include <sys/syscall.h>
17#include <asm/ldt.h>
18#include <sys/types.h>
19#include <sys/wait.h>
20#include <stdbool.h>
21#include <pthread.h>
22#include <sched.h>
23#include <linux/futex.h>
d63f4b52
AL		 24#include <sys/mman.h>
25#include <asm/prctl.h>
26#include <sys/prctl.h>
014dc90b
AL		 27
28#define AR_ACCESSED (1<<8)
29
30#define AR_TYPE_RODATA (0 * (1<<9))
31#define AR_TYPE_RWDATA (1 * (1<<9))
32#define AR_TYPE_RODATA_EXPDOWN (2 * (1<<9))
33#define AR_TYPE_RWDATA_EXPDOWN (3 * (1<<9))
34#define AR_TYPE_XOCODE (4 * (1<<9))
35#define AR_TYPE_XRCODE (5 * (1<<9))
36#define AR_TYPE_XOCODE_CONF (6 * (1<<9))
37#define AR_TYPE_XRCODE_CONF (7 * (1<<9))
38
39#define AR_DPL3 (3 * (1<<13))
40
41#define AR_S (1 << 12)
42#define AR_P (1 << 15)
43#define AR_AVL (1 << 20)
44#define AR_L (1 << 21)
45#define AR_DB (1 << 22)
46#define AR_G (1 << 23)
47
48static int nerrs;
49
d63f4b52
AL		 50/* Points to an array of 1024 ints, each holding its own index. */
51static const unsigned int *counter_page;
52static struct user_desc *low_user_desc;
53static struct user_desc *low_user_desc_clear; /* Use to delete GDT entry */
54static int gdt_entry_num;
55
014dc90b
AL		 56static void check_invalid_segment(uint16_t index, int ldt)
57{
58 uint32_t has_limit = 0, has_ar = 0, limit, ar;
59 uint32_t selector = (index << 3) | (ldt << 2) | 3;
60
61 asm ("lsl %[selector], %[limit]\n\t"
62 "jnz 1f\n\t"
63 "movl $1, %[has_limit]\n\t"
64 "1:"
65 : [limit] "=r" (limit), [has_limit] "+rm" (has_limit)
66 : [selector] "r" (selector));
67 asm ("larl %[selector], %[ar]\n\t"
68 "jnz 1f\n\t"
69 "movl $1, %[has_ar]\n\t"
70 "1:"
71 : [ar] "=r" (ar), [has_ar] "+rm" (has_ar)
72 : [selector] "r" (selector));
73
74 if (has_limit || has_ar) {
75 printf("[FAIL]\t%s entry %hu is valid but should be invalid\n",
76 (ldt ? "LDT" : "GDT"), index);
77 nerrs++;
78 } else {
79 printf("[OK]\t%s entry %hu is invalid\n",
80 (ldt ? "LDT" : "GDT"), index);
81 }
82}
83
84static void check_valid_segment(uint16_t index, int ldt,
85 uint32_t expected_ar, uint32_t expected_limit,
86 bool verbose)
87{
88 uint32_t has_limit = 0, has_ar = 0, limit, ar;
89 uint32_t selector = (index << 3) | (ldt << 2) | 3;
90
91 asm ("lsl %[selector], %[limit]\n\t"
92 "jnz 1f\n\t"
93 "movl $1, %[has_limit]\n\t"
94 "1:"
95 : [limit] "=r" (limit), [has_limit] "+rm" (has_limit)
96 : [selector] "r" (selector));
97 asm ("larl %[selector], %[ar]\n\t"
98 "jnz 1f\n\t"
99 "movl $1, %[has_ar]\n\t"
100 "1:"
101 : [ar] "=r" (ar), [has_ar] "+rm" (has_ar)
102 : [selector] "r" (selector));
103
104 if (!has_limit || !has_ar) {
105 printf("[FAIL]\t%s entry %hu is invalid but should be valid\n",
106 (ldt ? "LDT" : "GDT"), index);
107 nerrs++;
108 return;
109 }
110
111 if (ar != expected_ar) {
112 printf("[FAIL]\t%s entry %hu has AR 0x%08X but expected 0x%08X\n",
113 (ldt ? "LDT" : "GDT"), index, ar, expected_ar);
114 nerrs++;
115 } else if (limit != expected_limit) {
116 printf("[FAIL]\t%s entry %hu has limit 0x%08X but expected 0x%08X\n",
117 (ldt ? "LDT" : "GDT"), index, limit, expected_limit);
118 nerrs++;
119 } else if (verbose) {
120 printf("[OK]\t%s entry %hu has AR 0x%08X and limit 0x%08X\n",
121 (ldt ? "LDT" : "GDT"), index, ar, limit);
122 }
123}
124
125static bool install_valid_mode(const struct user_desc *desc, uint32_t ar,
126 bool oldmode)
127{
128 int ret = syscall(SYS_modify_ldt, oldmode ? 1 : 0x11,
129 desc, sizeof(*desc));
130 if (ret < -1)
131 errno = -ret;
132 if (ret == 0) {
133 uint32_t limit = desc->limit;
134 if (desc->limit_in_pages)
135 limit = (limit << 12) + 4095;
136 check_valid_segment(desc->entry_number, 1, ar, limit, true);
137 return true;
138 } else if (errno == ENOSYS) {
139 printf("[OK]\tmodify_ldt returned -ENOSYS\n");
140 return false;
141 } else {
142 if (desc->seg_32bit) {
143 printf("[FAIL]\tUnexpected modify_ldt failure %d\n",
144 errno);
145 nerrs++;
146 return false;
147 } else {
148 printf("[OK]\tmodify_ldt rejected 16 bit segment\n");
149 return false;
150 }
151 }
152}
153
154static bool install_valid(const struct user_desc *desc, uint32_t ar)
155{
156 return install_valid_mode(desc, ar, false);
157}
158
159static void install_invalid(const struct user_desc *desc, bool oldmode)
160{
161 int ret = syscall(SYS_modify_ldt, oldmode ? 1 : 0x11,
162 desc, sizeof(*desc));
163 if (ret < -1)
164 errno = -ret;
165 if (ret == 0) {
166 check_invalid_segment(desc->entry_number, 1);
167 } else if (errno == ENOSYS) {
168 printf("[OK]\tmodify_ldt returned -ENOSYS\n");
169 } else {
170 if (desc->seg_32bit) {
171 printf("[FAIL]\tUnexpected modify_ldt failure %d\n",
172 errno);
173 nerrs++;
174 } else {
175 printf("[OK]\tmodify_ldt rejected 16 bit segment\n");
176 }
177 }
178}
179
180static int safe_modify_ldt(int func, struct user_desc *ptr,
181 unsigned long bytecount)
182{
183 int ret = syscall(SYS_modify_ldt, 0x11, ptr, bytecount);
184 if (ret < -1)
185 errno = -ret;
186 return ret;
187}
188
189static void fail_install(struct user_desc *desc)
190{
191 if (safe_modify_ldt(0x11, desc, sizeof(*desc)) == 0) {
192 printf("[FAIL]\tmodify_ldt accepted a bad descriptor\n");
193 nerrs++;
194 } else if (errno == ENOSYS) {
195 printf("[OK]\tmodify_ldt returned -ENOSYS\n");
196 } else {
197 printf("[OK]\tmodify_ldt failure %d\n", errno);
198 }
199}
200
201static void do_simple_tests(void)
202{
203 struct user_desc desc = {
204 .entry_number = 0,
205 .base_addr = 0,
206 .limit = 10,
207 .seg_32bit = 1,
208 .contents = 2, /* Code, not conforming */
209 .read_exec_only = 0,
210 .limit_in_pages = 0,
211 .seg_not_present = 0,
212 .useable = 0
213 };
214 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE | AR_S | AR_P | AR_DB);
215
216 desc.limit_in_pages = 1;
217 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
218 AR_S | AR_P | AR_DB | AR_G);
219
220 check_invalid_segment(1, 1);
221
222 desc.entry_number = 2;
223 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
224 AR_S | AR_P | AR_DB | AR_G);
225
226 check_invalid_segment(1, 1);
227
228 desc.base_addr = 0xf0000000;
229 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
230 AR_S | AR_P | AR_DB | AR_G);
231
232 desc.useable = 1;
233 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
234 AR_S | AR_P | AR_DB | AR_G | AR_AVL);
235
236 desc.seg_not_present = 1;
237 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
238 AR_S | AR_DB | AR_G | AR_AVL);
239
240 desc.seg_32bit = 0;
241 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
242 AR_S | AR_G | AR_AVL);
243
244 desc.seg_32bit = 1;
245 desc.contents = 0;
246 install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA |
247 AR_S | AR_DB | AR_G | AR_AVL);
248
249 desc.read_exec_only = 1;
250 install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA |
251 AR_S | AR_DB | AR_G | AR_AVL);
252
253 desc.contents = 1;
254 install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA_EXPDOWN |
255 AR_S | AR_DB | AR_G | AR_AVL);
256
257 desc.read_exec_only = 0;
258 desc.limit_in_pages = 0;
259 install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA_EXPDOWN |
260 AR_S | AR_DB | AR_AVL);
261
262 desc.contents = 3;
263 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE_CONF |
264 AR_S | AR_DB | AR_AVL);
265
266 desc.read_exec_only = 1;
267 install_valid(&desc, AR_DPL3 | AR_TYPE_XOCODE_CONF |
268 AR_S | AR_DB | AR_AVL);
269
270 desc.read_exec_only = 0;
271 desc.contents = 2;
272 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE |
273 AR_S | AR_DB | AR_AVL);
274
275 desc.read_exec_only = 1;
276
277#ifdef __x86_64__
278 desc.lm = 1;
279 install_valid(&desc, AR_DPL3 | AR_TYPE_XOCODE |
280 AR_S | AR_DB | AR_AVL);
281 desc.lm = 0;
282#endif
283
284 bool entry1_okay = install_valid(&desc, AR_DPL3 | AR_TYPE_XOCODE |
285 AR_S | AR_DB | AR_AVL);
286
287 if (entry1_okay) {
288 printf("[RUN]\tTest fork\n");
289 pid_t child = fork();
290 if (child == 0) {
291 nerrs = 0;
292 check_valid_segment(desc.entry_number, 1,
293 AR_DPL3 | AR_TYPE_XOCODE |
294 AR_S | AR_DB | AR_AVL, desc.limit,
295 true);
296 check_invalid_segment(1, 1);
297 exit(nerrs ? 1 : 0);
298 } else {
299 int status;
300 if (waitpid(child, &status, 0) != child ||
301 !WIFEXITED(status)) {
302 printf("[FAIL]\tChild died\n");
303 nerrs++;
304 } else if (WEXITSTATUS(status) != 0) {
305 printf("[FAIL]\tChild failed\n");
306 nerrs++;
307 } else {
308 printf("[OK]\tChild succeeded\n");
309 }
310 }
311
312 printf("[RUN]\tTest size\n");
313 int i;
314 for (i = 0; i < 8192; i++) {
315 desc.entry_number = i;
316 desc.limit = i;
317 if (safe_modify_ldt(0x11, &desc, sizeof(desc)) != 0) {
318 printf("[FAIL]\tFailed to install entry %d\n", i);
319 nerrs++;
320 break;
321 }
322 }
323 for (int j = 0; j < i; j++) {
324 check_valid_segment(j, 1, AR_DPL3 | AR_TYPE_XOCODE |
325 AR_S | AR_DB | AR_AVL, j, false);
326 }
327 printf("[DONE]\tSize test\n");
328 } else {
329 printf("[SKIP]\tSkipping fork and size tests because we have no LDT\n");
330 }
331
332 /* Test entry_number too high. */
333 desc.entry_number = 8192;
334 fail_install(&desc);
335
336 /* Test deletion and actions mistakeable for deletion. */
337 memset(&desc, 0, sizeof(desc));
338 install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S | AR_P);
339
340 desc.seg_not_present = 1;
341 install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S);
342
343 desc.seg_not_present = 0;
344 desc.read_exec_only = 1;
345 install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA | AR_S | AR_P);
346
347 desc.read_exec_only = 0;
348 desc.seg_not_present = 1;
349 install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S);
350
351 desc.read_exec_only = 1;
352 desc.limit = 1;
353 install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA | AR_S);
354
355 desc.limit = 0;
356 desc.base_addr = 1;
357 install_valid(&desc, AR_DPL3 | AR_TYPE_RODATA | AR_S);
358
359 desc.base_addr = 0;
360 install_invalid(&desc, false);
361
362 desc.seg_not_present = 0;
363 desc.read_exec_only = 0;
364 desc.seg_32bit = 1;
365 install_valid(&desc, AR_DPL3 | AR_TYPE_RWDATA | AR_S | AR_P | AR_DB);
366 install_invalid(&desc, true);
367}
368
369/*
370 * 0: thread is idle
371 * 1: thread armed
372 * 2: thread should clear LDT entry 0
373 * 3: thread should exit
374 */
375static volatile unsigned int ftx;
376
377static void *threadproc(void *ctx)
378{
379 cpu_set_t cpuset;
380 CPU_ZERO(&cpuset);
381 CPU_SET(1, &cpuset);
382 if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0)
383 err(1, "sched_setaffinity to CPU 1"); /* should never fail */
384
385 while (1) {
386 syscall(SYS_futex, &ftx, FUTEX_WAIT, 0, NULL, NULL, 0);
387 while (ftx != 2) {
388 if (ftx >= 3)
389 return NULL;
390 }
391
392 /* clear LDT entry 0 */
393 const struct user_desc desc = {};
394 if (syscall(SYS_modify_ldt, 1, &desc, sizeof(desc)) != 0)
395 err(1, "modify_ldt");
396
397 /* If ftx == 2, set it to zero. If ftx == 100, quit. */
398 unsigned int x = -2;
399 asm volatile ("lock xaddl %[x], %[ftx]" :
400 [x] "+r" (x), [ftx] "+m" (ftx));
401 if (x != 2)
402 return NULL;
403 }
404}
405
406static void sethandler(int sig, void (*handler)(int, siginfo_t *, void *),
407 int flags)
408{
409 struct sigaction sa;
410 memset(&sa, 0, sizeof(sa));
411 sa.sa_sigaction = handler;
412 sa.sa_flags = SA_SIGINFO | flags;
413 sigemptyset(&sa.sa_mask);
414 if (sigaction(sig, &sa, 0))
415 err(1, "sigaction");
416
417}
418
419static jmp_buf jmpbuf;
420
421static void sigsegv(int sig, siginfo_t *info, void *ctx_void)
422{
423 siglongjmp(jmpbuf, 1);
424}
425
426static void do_multicpu_tests(void)
427{
428 cpu_set_t cpuset;
429 pthread_t thread;
430 int failures = 0, iters = 5, i;
431 unsigned short orig_ss;
432
433 CPU_ZERO(&cpuset);
434 CPU_SET(1, &cpuset);
435 if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0) {
436 printf("[SKIP]\tCannot set affinity to CPU 1\n");
437 return;
438 }
439
440 CPU_ZERO(&cpuset);
441 CPU_SET(0, &cpuset);
442 if (sched_setaffinity(0, sizeof(cpuset), &cpuset) != 0) {
443 printf("[SKIP]\tCannot set affinity to CPU 0\n");
444 return;
445 }
446
447 sethandler(SIGSEGV, sigsegv, 0);
448#ifdef __i386__
449 /* True 32-bit kernels send SIGILL instead of SIGSEGV on IRET faults. */
450 sethandler(SIGILL, sigsegv, 0);
451#endif
452
453 printf("[RUN]\tCross-CPU LDT invalidation\n");
454
455 if (pthread_create(&thread, 0, threadproc, 0) != 0)
456 err(1, "pthread_create");
457
458 asm volatile ("mov %%ss, %0" : "=rm" (orig_ss));
459
460 for (i = 0; i < 5; i++) {
461 if (sigsetjmp(jmpbuf, 1) != 0)
462 continue;
463
464 /* Make sure the thread is ready after the last test. */
465 while (ftx != 0)
466 ;
467
468 struct user_desc desc = {
469 .entry_number = 0,
470 .base_addr = 0,
471 .limit = 0xfffff,
472 .seg_32bit = 1,
473 .contents = 0, /* Data */
474 .read_exec_only = 0,
475 .limit_in_pages = 1,
476 .seg_not_present = 0,
477 .useable = 0
478 };
479
480 if (safe_modify_ldt(0x11, &desc, sizeof(desc)) != 0) {
481 if (errno != ENOSYS)
482 err(1, "modify_ldt");
483 printf("[SKIP]\tmodify_ldt unavailable\n");
484 break;
485 }
486
487 /* Arm the thread. */
488 ftx = 1;
489 syscall(SYS_futex, &ftx, FUTEX_WAKE, 0, NULL, NULL, 0);
490
491 asm volatile ("mov %0, %%ss" : : "r" (0x7));
492
493 /* Go! */
494 ftx = 2;
495
496 while (ftx != 0)
497 ;
498
499 /*
500 * On success, modify_ldt will segfault us synchronously,
501 * and we'll escape via siglongjmp.
502 */
503
504 failures++;
505 asm volatile ("mov %0, %%ss" : : "rm" (orig_ss));
506 };
507
508 ftx = 100; /* Kill the thread. */
509 syscall(SYS_futex, &ftx, FUTEX_WAKE, 0, NULL, NULL, 0);
510
511 if (pthread_join(thread, NULL) != 0)
512 err(1, "pthread_join");
513
514 if (failures) {
515 printf("[FAIL]\t%d of %d iterations failed\n", failures, iters);
516 nerrs++;
517 } else {
518 printf("[OK]\tAll %d iterations succeeded\n", iters);
519 }
520}
521
522static int finish_exec_test(void)
523{
524 /*
525 * In a sensible world, this would be check_invalid_segment(0, 1);
526 * For better or for worse, though, the LDT is inherited across exec.
527 * We can probably change this safely, but for now we test it.
528 */
529 check_valid_segment(0, 1,
530 AR_DPL3 | AR_TYPE_XRCODE | AR_S | AR_P | AR_DB,
531 42, true);
532
533 return nerrs ? 1 : 0;
534}
535
536static void do_exec_test(void)
537{
538 printf("[RUN]\tTest exec\n");
539
540 struct user_desc desc = {
541 .entry_number = 0,
542 .base_addr = 0,
543 .limit = 42,
544 .seg_32bit = 1,
545 .contents = 2, /* Code, not conforming */
546 .read_exec_only = 0,
547 .limit_in_pages = 0,
548 .seg_not_present = 0,
549 .useable = 0
550 };
551 install_valid(&desc, AR_DPL3 | AR_TYPE_XRCODE | AR_S | AR_P | AR_DB);
552
553 pid_t child = fork();
554 if (child == 0) {
555 execl("/proc/self/exe", "ldt_gdt_test_exec", NULL);
556 printf("[FAIL]\tCould not exec self\n");
557 exit(1); /* exec failed */
558 } else {
559 int status;
560 if (waitpid(child, &status, 0) != child ||
561 !WIFEXITED(status)) {
562 printf("[FAIL]\tChild died\n");
563 nerrs++;
564 } else if (WEXITSTATUS(status) != 0) {
565 printf("[FAIL]\tChild failed\n");
566 nerrs++;
567 } else {
568 printf("[OK]\tChild succeeded\n");
569 }
570 }
571}
572
d63f4b52
AL		 573static void setup_counter_page(void)
574{
575 unsigned int *page = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
576 MAP_ANONYMOUS | MAP_PRIVATE | MAP_32BIT, -1, 0);
577 if (page == MAP_FAILED)
578 err(1, "mmap");
579
580 for (int i = 0; i < 1024; i++)
581 page[i] = i;
582 counter_page = page;
583}
584
585static int invoke_set_thread_area(void)
586{
587 int ret;
588 asm volatile ("int $0x80"
589 : "=a" (ret), "+m" (low_user_desc) :
590 "a" (243), "b" (low_user_desc)
591 : "flags");
592 return ret;
593}
594
595static void setup_low_user_desc(void)
596{
597 low_user_desc = mmap(NULL, 2 * sizeof(struct user_desc),
598 PROT_READ | PROT_WRITE,
599 MAP_ANONYMOUS | MAP_PRIVATE | MAP_32BIT, -1, 0);
600 if (low_user_desc == MAP_FAILED)
601 err(1, "mmap");
602
603 low_user_desc->entry_number = -1;
604 low_user_desc->base_addr = (unsigned long)&counter_page[1];
605 low_user_desc->limit = 0xfffff;
606 low_user_desc->seg_32bit = 1;
607 low_user_desc->contents = 0; /* Data, grow-up*/
608 low_user_desc->read_exec_only = 0;
609 low_user_desc->limit_in_pages = 1;
610 low_user_desc->seg_not_present = 0;
611 low_user_desc->useable = 0;
612
613 if (invoke_set_thread_area() == 0) {
614 gdt_entry_num = low_user_desc->entry_number;
615 printf("[NOTE]\tset_thread_area is available; will use GDT index %d\n", gdt_entry_num);
616 } else {
617 printf("[NOTE]\tset_thread_area is unavailable\n");
618 }
619
620 low_user_desc_clear = low_user_desc + 1;
621 low_user_desc_clear->entry_number = gdt_entry_num;
622 low_user_desc_clear->read_exec_only = 1;
623 low_user_desc_clear->seg_not_present = 1;
624}
625
626static void test_gdt_invalidation(void)
627{
628 if (!gdt_entry_num)
629 return; /* 64-bit only system -- we can't use set_thread_area */
630
631 unsigned short prev_sel;
632 unsigned short sel;
633 unsigned int eax;
634 const char *result;
635#ifdef __x86_64__
636 unsigned long saved_base;
637 unsigned long new_base;
638#endif
639
640 /* Test DS */
641 invoke_set_thread_area();
642 eax = 243;
643 sel = (gdt_entry_num << 3) | 3;
644 asm volatile ("movw %%ds, %[prev_sel]\n\t"
645 "movw %[sel], %%ds\n\t"
646#ifdef __i386__
647 "pushl %%ebx\n\t"
648#endif
649 "movl %[arg1], %%ebx\n\t"
650 "int $0x80\n\t" /* Should invalidate ds */
651#ifdef __i386__
652 "popl %%ebx\n\t"
653#endif
654 "movw %%ds, %[sel]\n\t"
655 "movw %[prev_sel], %%ds"
656 : [prev_sel] "=&r" (prev_sel), [sel] "+r" (sel),
657 "+a" (eax)
658 : "m" (low_user_desc_clear),
659 [arg1] "r" ((unsigned int)(unsigned long)low_user_desc_clear)
660 : "flags");
661
662 if (sel != 0) {
663 result = "FAIL";
664 nerrs++;
665 } else {
666 result = "OK";
667 }
668 printf("[%s]\tInvalidate DS with set_thread_area: new DS = 0x%hx\n",
669 result, sel);
670
671 /* Test ES */
672 invoke_set_thread_area();
673 eax = 243;
674 sel = (gdt_entry_num << 3) | 3;
675 asm volatile ("movw %%es, %[prev_sel]\n\t"
676 "movw %[sel], %%es\n\t"
677#ifdef __i386__
678 "pushl %%ebx\n\t"
679#endif
680 "movl %[arg1], %%ebx\n\t"
681 "int $0x80\n\t" /* Should invalidate es */
682#ifdef __i386__
683 "popl %%ebx\n\t"
684#endif
685 "movw %%es, %[sel]\n\t"
686 "movw %[prev_sel], %%es"
687 : [prev_sel] "=&r" (prev_sel), [sel] "+r" (sel),
688 "+a" (eax)
689 : "m" (low_user_desc_clear),
690 [arg1] "r" ((unsigned int)(unsigned long)low_user_desc_clear)
691 : "flags");
692
693 if (sel != 0) {
694 result = "FAIL";
695 nerrs++;
696 } else {
697 result = "OK";
698 }
699 printf("[%s]\tInvalidate ES with set_thread_area: new ES = 0x%hx\n",
700 result, sel);
701
702 /* Test FS */
703 invoke_set_thread_area();
704 eax = 243;
705 sel = (gdt_entry_num << 3) | 3;
706#ifdef __x86_64__
707 syscall(SYS_arch_prctl, ARCH_GET_FS, &saved_base);
708#endif
709 asm volatile ("movw %%fs, %[prev_sel]\n\t"
710 "movw %[sel], %%fs\n\t"
711#ifdef __i386__
712 "pushl %%ebx\n\t"
713#endif
714 "movl %[arg1], %%ebx\n\t"
715 "int $0x80\n\t" /* Should invalidate fs */
716#ifdef __i386__
717 "popl %%ebx\n\t"
718#endif
719 "movw %%fs, %[sel]\n\t"
720 : [prev_sel] "=&r" (prev_sel), [sel] "+r" (sel),
721 "+a" (eax)
722 : "m" (low_user_desc_clear),
723 [arg1] "r" ((unsigned int)(unsigned long)low_user_desc_clear)
724 : "flags");
725
726#ifdef __x86_64__
727 syscall(SYS_arch_prctl, ARCH_GET_FS, &new_base);
728#endif
729
730 /* Restore FS/BASE for glibc */
731 asm volatile ("movw %[prev_sel], %%fs" : : [prev_sel] "rm" (prev_sel));
732#ifdef __x86_64__
733 if (saved_base)
734 syscall(SYS_arch_prctl, ARCH_SET_FS, saved_base);
735#endif
736
737 if (sel != 0) {
738 result = "FAIL";
739 nerrs++;
740 } else {
741 result = "OK";
742 }
743 printf("[%s]\tInvalidate FS with set_thread_area: new FS = 0x%hx\n",
744 result, sel);
745
746#ifdef __x86_64__
747 if (sel == 0 && new_base != 0) {
748 nerrs++;
749 printf("[FAIL]\tNew FSBASE was 0x%lx\n", new_base);
750 } else {
751 printf("[OK]\tNew FSBASE was zero\n");
752 }
753#endif
754
755 /* Test GS */
756 invoke_set_thread_area();
757 eax = 243;
758 sel = (gdt_entry_num << 3) | 3;
759#ifdef __x86_64__
760 syscall(SYS_arch_prctl, ARCH_GET_GS, &saved_base);
761#endif
762 asm volatile ("movw %%gs, %[prev_sel]\n\t"
763 "movw %[sel], %%gs\n\t"
764#ifdef __i386__
765 "pushl %%ebx\n\t"
766#endif
767 "movl %[arg1], %%ebx\n\t"
768 "int $0x80\n\t" /* Should invalidate gs */
769#ifdef __i386__
770 "popl %%ebx\n\t"
771#endif
772 "movw %%gs, %[sel]\n\t"
773 : [prev_sel] "=&r" (prev_sel), [sel] "+r" (sel),
774 "+a" (eax)
775 : "m" (low_user_desc_clear),
776 [arg1] "r" ((unsigned int)(unsigned long)low_user_desc_clear)
777 : "flags");
778
779#ifdef __x86_64__
780 syscall(SYS_arch_prctl, ARCH_GET_GS, &new_base);
781#endif
782
783 /* Restore GS/BASE for glibc */
784 asm volatile ("movw %[prev_sel], %%gs" : : [prev_sel] "rm" (prev_sel));
785#ifdef __x86_64__
786 if (saved_base)
787 syscall(SYS_arch_prctl, ARCH_SET_GS, saved_base);
788#endif
789
790 if (sel != 0) {
791 result = "FAIL";
792 nerrs++;
793 } else {
794 result = "OK";
795 }
796 printf("[%s]\tInvalidate GS with set_thread_area: new GS = 0x%hx\n",
797 result, sel);
798
799#ifdef __x86_64__
800 if (sel == 0 && new_base != 0) {
801 nerrs++;
802 printf("[FAIL]\tNew GSBASE was 0x%lx\n", new_base);
803 } else {
804 printf("[OK]\tNew GSBASE was zero\n");
805 }
806#endif
807}
808
014dc90b
AL		 809int main(int argc, char **argv)
810{
811 if (argc == 1 && !strcmp(argv[0], "ldt_gdt_test_exec"))
812 return finish_exec_test();
813
d63f4b52
AL		 814 setup_counter_page();
815 setup_low_user_desc();
816
014dc90b
AL		 817 do_simple_tests();
818
819 do_multicpu_tests();
820
821 do_exec_test();
822
d63f4b52
AL		 823 test_gdt_invalidation();
824
014dc90b
AL		 825 return nerrs ? 1 : 0;
826}
Linux 6.x block layer and io_uring tree(s)