1 /*
2 * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
3 * Use of this source code is governed by the GPLv2 license.
4 *
5 * Test code for seccomp bpf.
6 */
7
8 #include <asm/siginfo.h>
9 #define __have_siginfo_t 1
10 #define __have_sigval_t 1
11 #define __have_sigevent_t 1
12
13 #include <errno.h>
14 #include <linux/filter.h>
15 #include <sys/prctl.h>
16 #include <sys/ptrace.h>
17 #include <sys/types.h>
18 #include <sys/user.h>
19 #include <linux/prctl.h>
20 #include <linux/ptrace.h>
21 #include <linux/seccomp.h>
22 #include <pthread.h>
23 #include <semaphore.h>
24 #include <signal.h>
25 #include <stddef.h>
26 #include <stdbool.h>
27 #include <string.h>
28 #include <time.h>
29 #include <linux/elf.h>
30 #include <sys/uio.h>
31 #include <sys/utsname.h>
32 #include <sys/fcntl.h>
33 #include <sys/mman.h>
34 #include <sys/times.h>
35
36 #define _GNU_SOURCE
37 #include <unistd.h>
38 #include <sys/syscall.h>
39
40 #include "test_harness.h"
41
42 #ifndef PR_SET_PTRACER
43 # define PR_SET_PTRACER 0x59616d61
44 #endif
45
46 #ifndef PR_SET_NO_NEW_PRIVS
47 #define PR_SET_NO_NEW_PRIVS 38
48 #define PR_GET_NO_NEW_PRIVS 39
49 #endif
50
51 #ifndef PR_SECCOMP_EXT
52 #define PR_SECCOMP_EXT 43
53 #endif
54
55 #ifndef SECCOMP_EXT_ACT
56 #define SECCOMP_EXT_ACT 1
57 #endif
58
59 #ifndef SECCOMP_EXT_ACT_TSYNC
60 #define SECCOMP_EXT_ACT_TSYNC 1
61 #endif
62
63 #ifndef SECCOMP_MODE_STRICT
64 #define SECCOMP_MODE_STRICT 1
65 #endif
66
67 #ifndef SECCOMP_MODE_FILTER
68 #define SECCOMP_MODE_FILTER 2
69 #endif
70
71 #ifndef SECCOMP_RET_KILL
72 #define SECCOMP_RET_KILL 0x00000000U /* kill the task immediately */
73 #define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
74 #define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
75 #define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
76 #define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
77
78 /* Masks for the return value sections. */
79 #define SECCOMP_RET_ACTION 0x7fff0000U
80 #define SECCOMP_RET_DATA 0x0000ffffU
81
82 struct seccomp_data {
83 int nr;
84 __u32 arch;
85 __u64 instruction_pointer;
86 __u64 args[6];
87 };
88 #endif
89
90 #if __BYTE_ORDER == __LITTLE_ENDIAN
91 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
92 #elif __BYTE_ORDER == __BIG_ENDIAN
93 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
94 #else
95 #error "wut? Unknown __BYTE_ORDER?!"
96 #endif
97
98 #define SIBLING_EXIT_UNKILLED 0xbadbeef
99 #define SIBLING_EXIT_FAILURE 0xbadface
100 #define SIBLING_EXIT_NEWPRIVS 0xbadfeed
101
TEST(mode_strict_support)102 TEST(mode_strict_support)
103 {
104 long ret;
105
106 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
107 ASSERT_EQ(0, ret) {
108 TH_LOG("Kernel does not support CONFIG_SECCOMP");
109 }
110 syscall(__NR_exit, 1);
111 }
112
TEST_SIGNAL(mode_strict_cannot_call_prctl,SIGKILL)113 TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
114 {
115 long ret;
116
117 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
118 ASSERT_EQ(0, ret) {
119 TH_LOG("Kernel does not support CONFIG_SECCOMP");
120 }
121 syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
122 NULL, NULL, NULL);
123 EXPECT_FALSE(true) {
124 TH_LOG("Unreachable!");
125 }
126 }
127
128 /* Note! This doesn't test no new privs behavior */
TEST(no_new_privs_support)129 TEST(no_new_privs_support)
130 {
131 long ret;
132
133 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
134 EXPECT_EQ(0, ret) {
135 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
136 }
137 }
138
139 /* Tests kernel support by checking for a copy_from_user() fault on * NULL. */
TEST(mode_filter_support)140 TEST(mode_filter_support)
141 {
142 long ret;
143
144 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
145 ASSERT_EQ(0, ret) {
146 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
147 }
148 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
149 EXPECT_EQ(-1, ret);
150 EXPECT_EQ(EFAULT, errno) {
151 TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
152 }
153 }
154
TEST(mode_filter_without_nnp)155 TEST(mode_filter_without_nnp)
156 {
157 struct sock_filter filter[] = {
158 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
159 };
160 struct sock_fprog prog = {
161 .len = (unsigned short)ARRAY_SIZE(filter),
162 .filter = filter,
163 };
164 long ret;
165
166 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
167 ASSERT_LE(0, ret) {
168 TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
169 }
170 errno = 0;
171 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
172 /* Succeeds with CAP_SYS_ADMIN, fails without */
173 /* TODO(wad) check caps not euid */
174 if (geteuid()) {
175 EXPECT_EQ(-1, ret);
176 EXPECT_EQ(EACCES, errno);
177 } else {
178 EXPECT_EQ(0, ret);
179 }
180 }
181
182 #define MAX_INSNS_PER_PATH 32768
183
TEST(filter_size_limits)184 TEST(filter_size_limits)
185 {
186 int i;
187 int count = BPF_MAXINSNS + 1;
188 struct sock_filter allow[] = {
189 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
190 };
191 struct sock_filter *filter;
192 struct sock_fprog prog = { };
193 long ret;
194
195 filter = calloc(count, sizeof(*filter));
196 ASSERT_NE(NULL, filter);
197
198 for (i = 0; i < count; i++)
199 filter[i] = allow[0];
200
201 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
202 ASSERT_EQ(0, ret);
203
204 prog.filter = filter;
205 prog.len = count;
206
207 /* Too many filter instructions in a single filter. */
208 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
209 ASSERT_NE(0, ret) {
210 TH_LOG("Installing %d insn filter was allowed", prog.len);
211 }
212
213 /* One less is okay, though. */
214 prog.len -= 1;
215 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
216 ASSERT_EQ(0, ret) {
217 TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
218 }
219 }
220
TEST(filter_chain_limits)221 TEST(filter_chain_limits)
222 {
223 int i;
224 int count = BPF_MAXINSNS;
225 struct sock_filter allow[] = {
226 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
227 };
228 struct sock_filter *filter;
229 struct sock_fprog prog = { };
230 long ret;
231
232 filter = calloc(count, sizeof(*filter));
233 ASSERT_NE(NULL, filter);
234
235 for (i = 0; i < count; i++)
236 filter[i] = allow[0];
237
238 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
239 ASSERT_EQ(0, ret);
240
241 prog.filter = filter;
242 prog.len = 1;
243
244 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
245 ASSERT_EQ(0, ret);
246
247 prog.len = count;
248
249 /* Too many total filter instructions. */
250 for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
251 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
252 if (ret != 0)
253 break;
254 }
255 ASSERT_NE(0, ret) {
256 TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
257 i, count, i * (count + 4));
258 }
259 }
260
TEST(mode_filter_cannot_move_to_strict)261 TEST(mode_filter_cannot_move_to_strict)
262 {
263 struct sock_filter filter[] = {
264 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
265 };
266 struct sock_fprog prog = {
267 .len = (unsigned short)ARRAY_SIZE(filter),
268 .filter = filter,
269 };
270 long ret;
271
272 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
273 ASSERT_EQ(0, ret);
274
275 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
276 ASSERT_EQ(0, ret);
277
278 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
279 EXPECT_EQ(-1, ret);
280 EXPECT_EQ(EINVAL, errno);
281 }
282
283
TEST(mode_filter_get_seccomp)284 TEST(mode_filter_get_seccomp)
285 {
286 struct sock_filter filter[] = {
287 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
288 };
289 struct sock_fprog prog = {
290 .len = (unsigned short)ARRAY_SIZE(filter),
291 .filter = filter,
292 };
293 long ret;
294
295 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
296 ASSERT_EQ(0, ret);
297
298 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
299 EXPECT_EQ(0, ret);
300
301 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
302 ASSERT_EQ(0, ret);
303
304 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
305 EXPECT_EQ(2, ret);
306 }
307
308
TEST(ALLOW_all)309 TEST(ALLOW_all)
310 {
311 struct sock_filter filter[] = {
312 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
313 };
314 struct sock_fprog prog = {
315 .len = (unsigned short)ARRAY_SIZE(filter),
316 .filter = filter,
317 };
318 long ret;
319
320 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
321 ASSERT_EQ(0, ret);
322
323 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
324 ASSERT_EQ(0, ret);
325 }
326
TEST(empty_prog)327 TEST(empty_prog)
328 {
329 struct sock_filter filter[] = {
330 };
331 struct sock_fprog prog = {
332 .len = (unsigned short)ARRAY_SIZE(filter),
333 .filter = filter,
334 };
335 long ret;
336
337 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
338 ASSERT_EQ(0, ret);
339
340 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
341 EXPECT_EQ(-1, ret);
342 EXPECT_EQ(EINVAL, errno);
343 }
344
TEST_SIGNAL(unknown_ret_is_kill_inside,SIGSYS)345 TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
346 {
347 struct sock_filter filter[] = {
348 BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
349 };
350 struct sock_fprog prog = {
351 .len = (unsigned short)ARRAY_SIZE(filter),
352 .filter = filter,
353 };
354 long ret;
355
356 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
357 ASSERT_EQ(0, ret);
358
359 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
360 ASSERT_EQ(0, ret);
361 EXPECT_EQ(0, syscall(__NR_getpid)) {
362 TH_LOG("getpid() shouldn't ever return");
363 }
364 }
365
366 /* return code >= 0x80000000 is unused. */
TEST_SIGNAL(unknown_ret_is_kill_above_allow,SIGSYS)367 TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
368 {
369 struct sock_filter filter[] = {
370 BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
371 };
372 struct sock_fprog prog = {
373 .len = (unsigned short)ARRAY_SIZE(filter),
374 .filter = filter,
375 };
376 long ret;
377
378 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
379 ASSERT_EQ(0, ret);
380
381 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
382 ASSERT_EQ(0, ret);
383 EXPECT_EQ(0, syscall(__NR_getpid)) {
384 TH_LOG("getpid() shouldn't ever return");
385 }
386 }
387
TEST_SIGNAL(KILL_all,SIGSYS)388 TEST_SIGNAL(KILL_all, SIGSYS)
389 {
390 struct sock_filter filter[] = {
391 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
392 };
393 struct sock_fprog prog = {
394 .len = (unsigned short)ARRAY_SIZE(filter),
395 .filter = filter,
396 };
397 long ret;
398
399 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
400 ASSERT_EQ(0, ret);
401
402 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
403 ASSERT_EQ(0, ret);
404 }
405
TEST_SIGNAL(KILL_one,SIGSYS)406 TEST_SIGNAL(KILL_one, SIGSYS)
407 {
408 struct sock_filter filter[] = {
409 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
410 offsetof(struct seccomp_data, nr)),
411 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
412 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
413 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
414 };
415 struct sock_fprog prog = {
416 .len = (unsigned short)ARRAY_SIZE(filter),
417 .filter = filter,
418 };
419 long ret;
420 pid_t parent = getppid();
421
422 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
423 ASSERT_EQ(0, ret);
424
425 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
426 ASSERT_EQ(0, ret);
427
428 EXPECT_EQ(parent, syscall(__NR_getppid));
429 /* getpid() should never return. */
430 EXPECT_EQ(0, syscall(__NR_getpid));
431 }
432
TEST_SIGNAL(KILL_one_arg_one,SIGSYS)433 TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
434 {
435 void *fatal_address;
436 struct sock_filter filter[] = {
437 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
438 offsetof(struct seccomp_data, nr)),
439 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0),
440 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
441 /* Only both with lower 32-bit for now. */
442 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
443 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
444 (unsigned long)&fatal_address, 0, 1),
445 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
446 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
447 };
448 struct sock_fprog prog = {
449 .len = (unsigned short)ARRAY_SIZE(filter),
450 .filter = filter,
451 };
452 long ret;
453 pid_t parent = getppid();
454 struct tms timebuf;
455 clock_t clock = times(&timebuf);
456
457 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
458 ASSERT_EQ(0, ret);
459
460 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
461 ASSERT_EQ(0, ret);
462
463 EXPECT_EQ(parent, syscall(__NR_getppid));
464 EXPECT_LE(clock, syscall(__NR_times, &timebuf));
465 /* times() should never return. */
466 EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
467 }
468
TEST_SIGNAL(KILL_one_arg_six,SIGSYS)469 TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
470 {
471 #ifndef __NR_mmap2
472 int sysno = __NR_mmap;
473 #else
474 int sysno = __NR_mmap2;
475 #endif
476 struct sock_filter filter[] = {
477 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
478 offsetof(struct seccomp_data, nr)),
479 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0),
480 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
481 /* Only both with lower 32-bit for now. */
482 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
483 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
484 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
485 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
486 };
487 struct sock_fprog prog = {
488 .len = (unsigned short)ARRAY_SIZE(filter),
489 .filter = filter,
490 };
491 long ret;
492 pid_t parent = getppid();
493 int fd;
494 void *map1, *map2;
495 int page_size = sysconf(_SC_PAGESIZE);
496
497 ASSERT_LT(0, page_size);
498
499 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
500 ASSERT_EQ(0, ret);
501
502 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
503 ASSERT_EQ(0, ret);
504
505 fd = open("/dev/zero", O_RDONLY);
506 ASSERT_NE(-1, fd);
507
508 EXPECT_EQ(parent, syscall(__NR_getppid));
509 map1 = (void *)syscall(sysno,
510 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
511 EXPECT_NE(MAP_FAILED, map1);
512 /* mmap2() should never return. */
513 map2 = (void *)syscall(sysno,
514 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
515 EXPECT_EQ(MAP_FAILED, map2);
516
517 /* The test failed, so clean up the resources. */
518 munmap(map1, page_size);
519 munmap(map2, page_size);
520 close(fd);
521 }
522
523 /* TODO(wad) add 64-bit versus 32-bit arg tests. */
TEST(arg_out_of_range)524 TEST(arg_out_of_range)
525 {
526 struct sock_filter filter[] = {
527 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
528 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
529 };
530 struct sock_fprog prog = {
531 .len = (unsigned short)ARRAY_SIZE(filter),
532 .filter = filter,
533 };
534 long ret;
535
536 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
537 ASSERT_EQ(0, ret);
538
539 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
540 EXPECT_EQ(-1, ret);
541 EXPECT_EQ(EINVAL, errno);
542 }
543
TEST(ERRNO_valid)544 TEST(ERRNO_valid)
545 {
546 struct sock_filter filter[] = {
547 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
548 offsetof(struct seccomp_data, nr)),
549 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
550 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | E2BIG),
551 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
552 };
553 struct sock_fprog prog = {
554 .len = (unsigned short)ARRAY_SIZE(filter),
555 .filter = filter,
556 };
557 long ret;
558 pid_t parent = getppid();
559
560 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
561 ASSERT_EQ(0, ret);
562
563 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
564 ASSERT_EQ(0, ret);
565
566 EXPECT_EQ(parent, syscall(__NR_getppid));
567 EXPECT_EQ(-1, read(0, NULL, 0));
568 EXPECT_EQ(E2BIG, errno);
569 }
570
TEST(ERRNO_zero)571 TEST(ERRNO_zero)
572 {
573 struct sock_filter filter[] = {
574 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
575 offsetof(struct seccomp_data, nr)),
576 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
577 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | 0),
578 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
579 };
580 struct sock_fprog prog = {
581 .len = (unsigned short)ARRAY_SIZE(filter),
582 .filter = filter,
583 };
584 long ret;
585 pid_t parent = getppid();
586
587 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
588 ASSERT_EQ(0, ret);
589
590 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
591 ASSERT_EQ(0, ret);
592
593 EXPECT_EQ(parent, syscall(__NR_getppid));
594 /* "errno" of 0 is ok. */
595 EXPECT_EQ(0, read(0, NULL, 0));
596 }
597
TEST(ERRNO_capped)598 TEST(ERRNO_capped)
599 {
600 struct sock_filter filter[] = {
601 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
602 offsetof(struct seccomp_data, nr)),
603 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
604 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | 4096),
605 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
606 };
607 struct sock_fprog prog = {
608 .len = (unsigned short)ARRAY_SIZE(filter),
609 .filter = filter,
610 };
611 long ret;
612 pid_t parent = getppid();
613
614 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
615 ASSERT_EQ(0, ret);
616
617 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
618 ASSERT_EQ(0, ret);
619
620 EXPECT_EQ(parent, syscall(__NR_getppid));
621 EXPECT_EQ(-1, read(0, NULL, 0));
622 EXPECT_EQ(4095, errno);
623 }
624
FIXTURE_DATA(TRAP)625 FIXTURE_DATA(TRAP) {
626 struct sock_fprog prog;
627 };
628
FIXTURE_SETUP(TRAP)629 FIXTURE_SETUP(TRAP)
630 {
631 struct sock_filter filter[] = {
632 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
633 offsetof(struct seccomp_data, nr)),
634 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
635 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
636 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
637 };
638
639 memset(&self->prog, 0, sizeof(self->prog));
640 self->prog.filter = malloc(sizeof(filter));
641 ASSERT_NE(NULL, self->prog.filter);
642 memcpy(self->prog.filter, filter, sizeof(filter));
643 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
644 }
645
FIXTURE_TEARDOWN(TRAP)646 FIXTURE_TEARDOWN(TRAP)
647 {
648 if (self->prog.filter)
649 free(self->prog.filter);
650 }
651
TEST_F_SIGNAL(TRAP,dfl,SIGSYS)652 TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
653 {
654 long ret;
655
656 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
657 ASSERT_EQ(0, ret);
658
659 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
660 ASSERT_EQ(0, ret);
661 syscall(__NR_getpid);
662 }
663
664 /* Ensure that SIGSYS overrides SIG_IGN */
TEST_F_SIGNAL(TRAP,ign,SIGSYS)665 TEST_F_SIGNAL(TRAP, ign, SIGSYS)
666 {
667 long ret;
668
669 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
670 ASSERT_EQ(0, ret);
671
672 signal(SIGSYS, SIG_IGN);
673
674 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
675 ASSERT_EQ(0, ret);
676 syscall(__NR_getpid);
677 }
678
679 static struct siginfo TRAP_info;
680 static volatile int TRAP_nr;
TRAP_action(int nr,siginfo_t * info,void * void_context)681 static void TRAP_action(int nr, siginfo_t *info, void *void_context)
682 {
683 memcpy(&TRAP_info, info, sizeof(TRAP_info));
684 TRAP_nr = nr;
685 }
686
TEST_F(TRAP,handler)687 TEST_F(TRAP, handler)
688 {
689 int ret, test;
690 struct sigaction act;
691 sigset_t mask;
692
693 memset(&act, 0, sizeof(act));
694 sigemptyset(&mask);
695 sigaddset(&mask, SIGSYS);
696
697 act.sa_sigaction = &TRAP_action;
698 act.sa_flags = SA_SIGINFO;
699 ret = sigaction(SIGSYS, &act, NULL);
700 ASSERT_EQ(0, ret) {
701 TH_LOG("sigaction failed");
702 }
703 ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
704 ASSERT_EQ(0, ret) {
705 TH_LOG("sigprocmask failed");
706 }
707
708 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
709 ASSERT_EQ(0, ret);
710 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
711 ASSERT_EQ(0, ret);
712 TRAP_nr = 0;
713 memset(&TRAP_info, 0, sizeof(TRAP_info));
714 /* Expect the registers to be rolled back. (nr = error) may vary
715 * based on arch. */
716 ret = syscall(__NR_getpid);
717 /* Silence gcc warning about volatile. */
718 test = TRAP_nr;
719 EXPECT_EQ(SIGSYS, test);
720 struct local_sigsys {
721 void *_call_addr; /* calling user insn */
722 int _syscall; /* triggering system call number */
723 unsigned int _arch; /* AUDIT_ARCH_* of syscall */
724 } *sigsys = (struct local_sigsys *)
725 #ifdef si_syscall
726 &(TRAP_info.si_call_addr);
727 #else
728 &TRAP_info.si_pid;
729 #endif
730 EXPECT_EQ(__NR_getpid, sigsys->_syscall);
731 /* Make sure arch is non-zero. */
732 EXPECT_NE(0, sigsys->_arch);
733 EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
734 }
735
FIXTURE_DATA(precedence)736 FIXTURE_DATA(precedence) {
737 struct sock_fprog allow;
738 struct sock_fprog trace;
739 struct sock_fprog error;
740 struct sock_fprog trap;
741 struct sock_fprog kill;
742 };
743
FIXTURE_SETUP(precedence)744 FIXTURE_SETUP(precedence)
745 {
746 struct sock_filter allow_insns[] = {
747 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
748 };
749 struct sock_filter trace_insns[] = {
750 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
751 offsetof(struct seccomp_data, nr)),
752 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
753 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
754 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE),
755 };
756 struct sock_filter error_insns[] = {
757 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
758 offsetof(struct seccomp_data, nr)),
759 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
760 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
761 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO),
762 };
763 struct sock_filter trap_insns[] = {
764 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
765 offsetof(struct seccomp_data, nr)),
766 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
767 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
768 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
769 };
770 struct sock_filter kill_insns[] = {
771 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
772 offsetof(struct seccomp_data, nr)),
773 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
774 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
775 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
776 };
777
778 memset(self, 0, sizeof(*self));
779 #define FILTER_ALLOC(_x) \
780 self->_x.filter = malloc(sizeof(_x##_insns)); \
781 ASSERT_NE(NULL, self->_x.filter); \
782 memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
783 self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
784 FILTER_ALLOC(allow);
785 FILTER_ALLOC(trace);
786 FILTER_ALLOC(error);
787 FILTER_ALLOC(trap);
788 FILTER_ALLOC(kill);
789 }
790
FIXTURE_TEARDOWN(precedence)791 FIXTURE_TEARDOWN(precedence)
792 {
793 #define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
794 FILTER_FREE(allow);
795 FILTER_FREE(trace);
796 FILTER_FREE(error);
797 FILTER_FREE(trap);
798 FILTER_FREE(kill);
799 }
800
TEST_F(precedence,allow_ok)801 TEST_F(precedence, allow_ok)
802 {
803 pid_t parent, res = 0;
804 long ret;
805
806 parent = getppid();
807 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
808 ASSERT_EQ(0, ret);
809
810 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
811 ASSERT_EQ(0, ret);
812 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
813 ASSERT_EQ(0, ret);
814 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
815 ASSERT_EQ(0, ret);
816 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
817 ASSERT_EQ(0, ret);
818 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
819 ASSERT_EQ(0, ret);
820 /* Should work just fine. */
821 res = syscall(__NR_getppid);
822 EXPECT_EQ(parent, res);
823 }
824
TEST_F_SIGNAL(precedence,kill_is_highest,SIGSYS)825 TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
826 {
827 pid_t parent, res = 0;
828 long ret;
829
830 parent = getppid();
831 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
832 ASSERT_EQ(0, ret);
833
834 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
835 ASSERT_EQ(0, ret);
836 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
837 ASSERT_EQ(0, ret);
838 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
839 ASSERT_EQ(0, ret);
840 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
841 ASSERT_EQ(0, ret);
842 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
843 ASSERT_EQ(0, ret);
844 /* Should work just fine. */
845 res = syscall(__NR_getppid);
846 EXPECT_EQ(parent, res);
847 /* getpid() should never return. */
848 res = syscall(__NR_getpid);
849 EXPECT_EQ(0, res);
850 }
851
TEST_F_SIGNAL(precedence,kill_is_highest_in_any_order,SIGSYS)852 TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
853 {
854 pid_t parent;
855 long ret;
856
857 parent = getppid();
858 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
859 ASSERT_EQ(0, ret);
860
861 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
862 ASSERT_EQ(0, ret);
863 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
864 ASSERT_EQ(0, ret);
865 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
866 ASSERT_EQ(0, ret);
867 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
868 ASSERT_EQ(0, ret);
869 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
870 ASSERT_EQ(0, ret);
871 /* Should work just fine. */
872 EXPECT_EQ(parent, syscall(__NR_getppid));
873 /* getpid() should never return. */
874 EXPECT_EQ(0, syscall(__NR_getpid));
875 }
876
TEST_F_SIGNAL(precedence,trap_is_second,SIGSYS)877 TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
878 {
879 pid_t parent;
880 long ret;
881
882 parent = getppid();
883 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
884 ASSERT_EQ(0, ret);
885
886 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
887 ASSERT_EQ(0, ret);
888 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
889 ASSERT_EQ(0, ret);
890 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
891 ASSERT_EQ(0, ret);
892 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
893 ASSERT_EQ(0, ret);
894 /* Should work just fine. */
895 EXPECT_EQ(parent, syscall(__NR_getppid));
896 /* getpid() should never return. */
897 EXPECT_EQ(0, syscall(__NR_getpid));
898 }
899
TEST_F_SIGNAL(precedence,trap_is_second_in_any_order,SIGSYS)900 TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
901 {
902 pid_t parent;
903 long ret;
904
905 parent = getppid();
906 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
907 ASSERT_EQ(0, ret);
908
909 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
910 ASSERT_EQ(0, ret);
911 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
912 ASSERT_EQ(0, ret);
913 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
914 ASSERT_EQ(0, ret);
915 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
916 ASSERT_EQ(0, ret);
917 /* Should work just fine. */
918 EXPECT_EQ(parent, syscall(__NR_getppid));
919 /* getpid() should never return. */
920 EXPECT_EQ(0, syscall(__NR_getpid));
921 }
922
TEST_F(precedence,errno_is_third)923 TEST_F(precedence, errno_is_third)
924 {
925 pid_t parent;
926 long ret;
927
928 parent = getppid();
929 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
930 ASSERT_EQ(0, ret);
931
932 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
933 ASSERT_EQ(0, ret);
934 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
935 ASSERT_EQ(0, ret);
936 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
937 ASSERT_EQ(0, ret);
938 /* Should work just fine. */
939 EXPECT_EQ(parent, syscall(__NR_getppid));
940 EXPECT_EQ(0, syscall(__NR_getpid));
941 }
942
TEST_F(precedence,errno_is_third_in_any_order)943 TEST_F(precedence, errno_is_third_in_any_order)
944 {
945 pid_t parent;
946 long ret;
947
948 parent = getppid();
949 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
950 ASSERT_EQ(0, ret);
951
952 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
953 ASSERT_EQ(0, ret);
954 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
955 ASSERT_EQ(0, ret);
956 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
957 ASSERT_EQ(0, ret);
958 /* Should work just fine. */
959 EXPECT_EQ(parent, syscall(__NR_getppid));
960 EXPECT_EQ(0, syscall(__NR_getpid));
961 }
962
TEST_F(precedence,trace_is_fourth)963 TEST_F(precedence, trace_is_fourth)
964 {
965 pid_t parent;
966 long ret;
967
968 parent = getppid();
969 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
970 ASSERT_EQ(0, ret);
971
972 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
973 ASSERT_EQ(0, ret);
974 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
975 ASSERT_EQ(0, ret);
976 /* Should work just fine. */
977 EXPECT_EQ(parent, syscall(__NR_getppid));
978 /* No ptracer */
979 EXPECT_EQ(-1, syscall(__NR_getpid));
980 }
981
TEST_F(precedence,trace_is_fourth_in_any_order)982 TEST_F(precedence, trace_is_fourth_in_any_order)
983 {
984 pid_t parent;
985 long ret;
986
987 parent = getppid();
988 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
989 ASSERT_EQ(0, ret);
990
991 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
992 ASSERT_EQ(0, ret);
993 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
994 ASSERT_EQ(0, ret);
995 /* Should work just fine. */
996 EXPECT_EQ(parent, syscall(__NR_getppid));
997 /* No ptracer */
998 EXPECT_EQ(-1, syscall(__NR_getpid));
999 }
1000
1001 #ifndef PTRACE_O_TRACESECCOMP
1002 #define PTRACE_O_TRACESECCOMP 0x00000080
1003 #endif
1004
1005 /* Catch the Ubuntu 12.04 value error. */
1006 #if PTRACE_EVENT_SECCOMP != 7
1007 #undef PTRACE_EVENT_SECCOMP
1008 #endif
1009
1010 #ifndef PTRACE_EVENT_SECCOMP
1011 #define PTRACE_EVENT_SECCOMP 7
1012 #endif
1013
1014 #define IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP)
1015 bool tracer_running;
tracer_stop(int sig)1016 void tracer_stop(int sig)
1017 {
1018 tracer_running = false;
1019 }
1020
1021 typedef void tracer_func_t(struct __test_metadata *_metadata,
1022 pid_t tracee, int status, void *args);
1023
tracer(struct __test_metadata * _metadata,int fd,pid_t tracee,tracer_func_t tracer_func,void * args)1024 void tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
1025 tracer_func_t tracer_func, void *args)
1026 {
1027 int ret = -1;
1028 struct sigaction action = {
1029 .sa_handler = tracer_stop,
1030 };
1031
1032 /* Allow external shutdown. */
1033 tracer_running = true;
1034 ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));
1035
1036 errno = 0;
1037 while (ret == -1 && errno != EINVAL)
1038 ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
1039 ASSERT_EQ(0, ret) {
1040 kill(tracee, SIGKILL);
1041 }
1042 /* Wait for attach stop */
1043 wait(NULL);
1044
1045 ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, PTRACE_O_TRACESECCOMP);
1046 ASSERT_EQ(0, ret) {
1047 TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
1048 kill(tracee, SIGKILL);
1049 }
1050 ptrace(PTRACE_CONT, tracee, NULL, 0);
1051
1052 /* Unblock the tracee */
1053 ASSERT_EQ(1, write(fd, "A", 1));
1054 ASSERT_EQ(0, close(fd));
1055
1056 /* Run until we're shut down. Must assert to stop execution. */
1057 while (tracer_running) {
1058 int status;
1059
1060 if (wait(&status) != tracee)
1061 continue;
1062 if (WIFSIGNALED(status) || WIFEXITED(status))
1063 /* Child is dead. Time to go. */
1064 return;
1065
1066 /* Make sure this is a seccomp event. */
1067 ASSERT_EQ(true, IS_SECCOMP_EVENT(status));
1068
1069 tracer_func(_metadata, tracee, status, args);
1070
1071 ret = ptrace(PTRACE_CONT, tracee, NULL, NULL);
1072 ASSERT_EQ(0, ret);
1073 }
1074 /* Directly report the status of our test harness results. */
1075 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
1076 }
1077
1078 /* Common tracer setup/teardown functions. */
cont_handler(int num)1079 void cont_handler(int num)
1080 { }
setup_trace_fixture(struct __test_metadata * _metadata,tracer_func_t func,void * args)1081 pid_t setup_trace_fixture(struct __test_metadata *_metadata,
1082 tracer_func_t func, void *args)
1083 {
1084 char sync;
1085 int pipefd[2];
1086 pid_t tracer_pid;
1087 pid_t tracee = getpid();
1088
1089 /* Setup a pipe for clean synchronization. */
1090 ASSERT_EQ(0, pipe(pipefd));
1091
1092 /* Fork a child which we'll promote to tracer */
1093 tracer_pid = fork();
1094 ASSERT_LE(0, tracer_pid);
1095 signal(SIGALRM, cont_handler);
1096 if (tracer_pid == 0) {
1097 close(pipefd[0]);
1098 tracer(_metadata, pipefd[1], tracee, func, args);
1099 syscall(__NR_exit, 0);
1100 }
1101 close(pipefd[1]);
1102 prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
1103 read(pipefd[0], &sync, 1);
1104 close(pipefd[0]);
1105
1106 return tracer_pid;
1107 }
teardown_trace_fixture(struct __test_metadata * _metadata,pid_t tracer)1108 void teardown_trace_fixture(struct __test_metadata *_metadata,
1109 pid_t tracer)
1110 {
1111 if (tracer) {
1112 int status;
1113 /*
1114 * Extract the exit code from the other process and
1115 * adopt it for ourselves in case its asserts failed.
1116 */
1117 ASSERT_EQ(0, kill(tracer, SIGUSR1));
1118 ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
1119 if (WEXITSTATUS(status))
1120 _metadata->passed = 0;
1121 }
1122 }
1123
1124 /* "poke" tracer arguments and function. */
1125 struct tracer_args_poke_t {
1126 unsigned long poke_addr;
1127 };
1128
tracer_poke(struct __test_metadata * _metadata,pid_t tracee,int status,void * args)1129 void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
1130 void *args)
1131 {
1132 int ret;
1133 unsigned long msg;
1134 struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;
1135
1136 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1137 EXPECT_EQ(0, ret);
1138 /* If this fails, don't try to recover. */
1139 ASSERT_EQ(0x1001, msg) {
1140 kill(tracee, SIGKILL);
1141 }
1142 /*
1143 * Poke in the message.
1144 * Registers are not touched to try to keep this relatively arch
1145 * agnostic.
1146 */
1147 ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
1148 EXPECT_EQ(0, ret);
1149 }
1150
FIXTURE_DATA(TRACE_poke)1151 FIXTURE_DATA(TRACE_poke) {
1152 struct sock_fprog prog;
1153 pid_t tracer;
1154 long poked;
1155 struct tracer_args_poke_t tracer_args;
1156 };
1157
FIXTURE_SETUP(TRACE_poke)1158 FIXTURE_SETUP(TRACE_poke)
1159 {
1160 struct sock_filter filter[] = {
1161 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1162 offsetof(struct seccomp_data, nr)),
1163 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1164 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001),
1165 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1166 };
1167
1168 self->poked = 0;
1169 memset(&self->prog, 0, sizeof(self->prog));
1170 self->prog.filter = malloc(sizeof(filter));
1171 ASSERT_NE(NULL, self->prog.filter);
1172 memcpy(self->prog.filter, filter, sizeof(filter));
1173 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1174
1175 /* Set up tracer args. */
1176 self->tracer_args.poke_addr = (unsigned long)&self->poked;
1177
1178 /* Launch tracer. */
1179 self->tracer = setup_trace_fixture(_metadata, tracer_poke,
1180 &self->tracer_args);
1181 }
1182
FIXTURE_TEARDOWN(TRACE_poke)1183 FIXTURE_TEARDOWN(TRACE_poke)
1184 {
1185 teardown_trace_fixture(_metadata, self->tracer);
1186 if (self->prog.filter)
1187 free(self->prog.filter);
1188 }
1189
TEST_F(TRACE_poke,read_has_side_effects)1190 TEST_F(TRACE_poke, read_has_side_effects)
1191 {
1192 ssize_t ret;
1193
1194 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1195 ASSERT_EQ(0, ret);
1196
1197 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1198 ASSERT_EQ(0, ret);
1199
1200 EXPECT_EQ(0, self->poked);
1201 ret = read(-1, NULL, 0);
1202 EXPECT_EQ(-1, ret);
1203 EXPECT_EQ(0x1001, self->poked);
1204 }
1205
TEST_F(TRACE_poke,getpid_runs_normally)1206 TEST_F(TRACE_poke, getpid_runs_normally)
1207 {
1208 long ret;
1209
1210 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1211 ASSERT_EQ(0, ret);
1212
1213 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1214 ASSERT_EQ(0, ret);
1215
1216 EXPECT_EQ(0, self->poked);
1217 EXPECT_NE(0, syscall(__NR_getpid));
1218 EXPECT_EQ(0, self->poked);
1219 }
1220
1221 #if defined(__x86_64__)
1222 # define ARCH_REGS struct user_regs_struct
1223 # define SYSCALL_NUM orig_rax
1224 # define SYSCALL_RET rax
1225 #elif defined(__i386__)
1226 # define ARCH_REGS struct user_regs_struct
1227 # define SYSCALL_NUM orig_eax
1228 # define SYSCALL_RET eax
1229 #elif defined(__arm__)
1230 # define ARCH_REGS struct pt_regs
1231 # define SYSCALL_NUM ARM_r7
1232 # define SYSCALL_RET ARM_r0
1233 #elif defined(__aarch64__)
1234 # define ARCH_REGS struct user_pt_regs
1235 # define SYSCALL_NUM regs[8]
1236 # define SYSCALL_RET regs[0]
1237 #elif defined(__powerpc__)
1238 # define ARCH_REGS struct pt_regs
1239 # define SYSCALL_NUM gpr[0]
1240 # define SYSCALL_RET gpr[3]
1241 #elif defined(__s390__)
1242 # define ARCH_REGS s390_regs
1243 # define SYSCALL_NUM gprs[2]
1244 # define SYSCALL_RET gprs[2]
1245 #else
1246 # error "Do not know how to find your architecture's registers and syscalls"
1247 #endif
1248
1249 /* Architecture-specific syscall fetching routine. */
get_syscall(struct __test_metadata * _metadata,pid_t tracee)1250 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1251 {
1252 struct iovec iov;
1253 ARCH_REGS regs;
1254
1255 iov.iov_base = ®s;
1256 iov.iov_len = sizeof(regs);
1257 EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1258 TH_LOG("PTRACE_GETREGSET failed");
1259 return -1;
1260 }
1261
1262 return regs.SYSCALL_NUM;
1263 }
1264
1265 /* Architecture-specific syscall changing routine. */
change_syscall(struct __test_metadata * _metadata,pid_t tracee,int syscall)1266 void change_syscall(struct __test_metadata *_metadata,
1267 pid_t tracee, int syscall)
1268 {
1269 struct iovec iov;
1270 int ret;
1271 ARCH_REGS regs;
1272
1273 iov.iov_base = ®s;
1274 iov.iov_len = sizeof(regs);
1275 ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
1276 EXPECT_EQ(0, ret);
1277
1278 #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
1279 defined(__s390__)
1280 {
1281 regs.SYSCALL_NUM = syscall;
1282 }
1283
1284 #elif defined(__arm__)
1285 # ifndef PTRACE_SET_SYSCALL
1286 # define PTRACE_SET_SYSCALL 23
1287 # endif
1288 {
1289 ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
1290 EXPECT_EQ(0, ret);
1291 }
1292
1293 #elif defined(__aarch64__)
1294 # ifndef NT_ARM_SYSTEM_CALL
1295 # define NT_ARM_SYSTEM_CALL 0x404
1296 # endif
1297 {
1298 iov.iov_base = &syscall;
1299 iov.iov_len = sizeof(syscall);
1300 ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
1301 &iov);
1302 EXPECT_EQ(0, ret);
1303 }
1304
1305 #else
1306 ASSERT_EQ(1, 0) {
1307 TH_LOG("How is the syscall changed on this architecture?");
1308 }
1309 #endif
1310
1311 /* If syscall is skipped, change return value. */
1312 if (syscall == -1)
1313 regs.SYSCALL_RET = 1;
1314
1315 iov.iov_base = ®s;
1316 iov.iov_len = sizeof(regs);
1317 ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
1318 EXPECT_EQ(0, ret);
1319 }
1320
tracer_syscall(struct __test_metadata * _metadata,pid_t tracee,int status,void * args)1321 void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
1322 int status, void *args)
1323 {
1324 int ret;
1325 unsigned long msg;
1326
1327 /* Make sure we got the right message. */
1328 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1329 EXPECT_EQ(0, ret);
1330
1331 /* Validate and take action on expected syscalls. */
1332 switch (msg) {
1333 case 0x1002:
1334 /* change getpid to getppid. */
1335 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
1336 change_syscall(_metadata, tracee, __NR_getppid);
1337 break;
1338 case 0x1003:
1339 /* skip gettid. */
1340 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
1341 change_syscall(_metadata, tracee, -1);
1342 break;
1343 case 0x1004:
1344 /* do nothing (allow getppid) */
1345 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
1346 break;
1347 default:
1348 EXPECT_EQ(0, msg) {
1349 TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1350 kill(tracee, SIGKILL);
1351 }
1352 }
1353
1354 }
1355
FIXTURE_DATA(TRACE_syscall)1356 FIXTURE_DATA(TRACE_syscall) {
1357 struct sock_fprog prog;
1358 pid_t tracer, mytid, mypid, parent;
1359 };
1360
FIXTURE_SETUP(TRACE_syscall)1361 FIXTURE_SETUP(TRACE_syscall)
1362 {
1363 struct sock_filter filter[] = {
1364 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1365 offsetof(struct seccomp_data, nr)),
1366 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1367 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1368 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1369 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
1370 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1371 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
1372 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1373 };
1374
1375 memset(&self->prog, 0, sizeof(self->prog));
1376 self->prog.filter = malloc(sizeof(filter));
1377 ASSERT_NE(NULL, self->prog.filter);
1378 memcpy(self->prog.filter, filter, sizeof(filter));
1379 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1380
1381 /* Prepare some testable syscall results. */
1382 self->mytid = syscall(__NR_gettid);
1383 ASSERT_GT(self->mytid, 0);
1384 ASSERT_NE(self->mytid, 1) {
1385 TH_LOG("Running this test as init is not supported. :)");
1386 }
1387
1388 self->mypid = getpid();
1389 ASSERT_GT(self->mypid, 0);
1390 ASSERT_EQ(self->mytid, self->mypid);
1391
1392 self->parent = getppid();
1393 ASSERT_GT(self->parent, 0);
1394 ASSERT_NE(self->parent, self->mypid);
1395
1396 /* Launch tracer. */
1397 self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL);
1398 }
1399
FIXTURE_TEARDOWN(TRACE_syscall)1400 FIXTURE_TEARDOWN(TRACE_syscall)
1401 {
1402 teardown_trace_fixture(_metadata, self->tracer);
1403 if (self->prog.filter)
1404 free(self->prog.filter);
1405 }
1406
TEST_F(TRACE_syscall,syscall_allowed)1407 TEST_F(TRACE_syscall, syscall_allowed)
1408 {
1409 long ret;
1410
1411 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1412 ASSERT_EQ(0, ret);
1413
1414 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1415 ASSERT_EQ(0, ret);
1416
1417 /* getppid works as expected (no changes). */
1418 EXPECT_EQ(self->parent, syscall(__NR_getppid));
1419 EXPECT_NE(self->mypid, syscall(__NR_getppid));
1420 }
1421
TEST_F(TRACE_syscall,syscall_redirected)1422 TEST_F(TRACE_syscall, syscall_redirected)
1423 {
1424 long ret;
1425
1426 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1427 ASSERT_EQ(0, ret);
1428
1429 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1430 ASSERT_EQ(0, ret);
1431
1432 /* getpid has been redirected to getppid as expected. */
1433 EXPECT_EQ(self->parent, syscall(__NR_getpid));
1434 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1435 }
1436
TEST_F(TRACE_syscall,syscall_dropped)1437 TEST_F(TRACE_syscall, syscall_dropped)
1438 {
1439 long ret;
1440
1441 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1442 ASSERT_EQ(0, ret);
1443
1444 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1445 ASSERT_EQ(0, ret);
1446
1447 /* gettid has been skipped and an altered return value stored. */
1448 EXPECT_EQ(1, syscall(__NR_gettid));
1449 EXPECT_NE(self->mytid, syscall(__NR_gettid));
1450 }
1451
1452 #ifndef __NR_seccomp
1453 # if defined(__i386__)
1454 # define __NR_seccomp 354
1455 # elif defined(__x86_64__)
1456 # define __NR_seccomp 317
1457 # elif defined(__arm__)
1458 # define __NR_seccomp 383
1459 # elif defined(__aarch64__)
1460 # define __NR_seccomp 277
1461 # elif defined(__powerpc__)
1462 # define __NR_seccomp 358
1463 # elif defined(__s390__)
1464 # define __NR_seccomp 348
1465 # else
1466 # warning "seccomp syscall number unknown for this architecture"
1467 # define __NR_seccomp 0xffff
1468 # endif
1469 #endif
1470
1471 #ifndef SECCOMP_SET_MODE_STRICT
1472 #define SECCOMP_SET_MODE_STRICT 0
1473 #endif
1474
1475 #ifndef SECCOMP_SET_MODE_FILTER
1476 #define SECCOMP_SET_MODE_FILTER 1
1477 #endif
1478
1479 #ifndef SECCOMP_FILTER_FLAG_TSYNC
1480 #define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
1481 #endif
1482
1483 #ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
1484 #define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
1485 #endif
1486
1487 #ifndef seccomp
seccomp(unsigned int op,unsigned int flags,void * args)1488 int seccomp(unsigned int op, unsigned int flags, void *args)
1489 {
1490 errno = 0;
1491 return syscall(__NR_seccomp, op, flags, args);
1492 }
1493 #endif
1494
TEST(seccomp_syscall)1495 TEST(seccomp_syscall)
1496 {
1497 struct sock_filter filter[] = {
1498 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1499 };
1500 struct sock_fprog prog = {
1501 .len = (unsigned short)ARRAY_SIZE(filter),
1502 .filter = filter,
1503 };
1504 long ret;
1505
1506 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1507 ASSERT_EQ(0, ret) {
1508 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1509 }
1510
1511 /* Reject insane operation. */
1512 ret = seccomp(-1, 0, &prog);
1513 ASSERT_NE(ENOSYS, errno) {
1514 TH_LOG("Kernel does not support seccomp syscall!");
1515 }
1516 EXPECT_EQ(EINVAL, errno) {
1517 TH_LOG("Did not reject crazy op value!");
1518 }
1519
1520 /* Reject strict with flags or pointer. */
1521 ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
1522 EXPECT_EQ(EINVAL, errno) {
1523 TH_LOG("Did not reject mode strict with flags!");
1524 }
1525 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
1526 EXPECT_EQ(EINVAL, errno) {
1527 TH_LOG("Did not reject mode strict with uargs!");
1528 }
1529
1530 /* Reject insane args for filter. */
1531 ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
1532 EXPECT_EQ(EINVAL, errno) {
1533 TH_LOG("Did not reject crazy filter flags!");
1534 }
1535 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
1536 EXPECT_EQ(EFAULT, errno) {
1537 TH_LOG("Did not reject NULL filter!");
1538 }
1539
1540 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
1541 EXPECT_EQ(0, errno) {
1542 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
1543 strerror(errno));
1544 }
1545 }
1546
TEST(seccomp_syscall_mode_lock)1547 TEST(seccomp_syscall_mode_lock)
1548 {
1549 struct sock_filter filter[] = {
1550 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1551 };
1552 struct sock_fprog prog = {
1553 .len = (unsigned short)ARRAY_SIZE(filter),
1554 .filter = filter,
1555 };
1556 long ret;
1557
1558 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
1559 ASSERT_EQ(0, ret) {
1560 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1561 }
1562
1563 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
1564 ASSERT_NE(ENOSYS, errno) {
1565 TH_LOG("Kernel does not support seccomp syscall!");
1566 }
1567 EXPECT_EQ(0, ret) {
1568 TH_LOG("Could not install filter!");
1569 }
1570
1571 /* Make sure neither entry point will switch to strict. */
1572 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
1573 EXPECT_EQ(EINVAL, errno) {
1574 TH_LOG("Switched to mode strict!");
1575 }
1576
1577 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
1578 EXPECT_EQ(EINVAL, errno) {
1579 TH_LOG("Switched to mode strict!");
1580 }
1581 }
1582
1583 /*
1584 * Test detection of known and unknown filter flags. Userspace needs to be able
1585 * to check if a filter flag is supported by the current kernel and a good way
1586 * of doing that is by attempting to enter filter mode, with the flag bit in
1587 * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
1588 * that the flag is valid and EINVAL indicates that the flag is invalid.
1589 */
TEST(detect_seccomp_filter_flags)1590 TEST(detect_seccomp_filter_flags)
1591 {
1592 unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
1593 SECCOMP_FILTER_FLAG_SPEC_ALLOW };
1594 unsigned int flag, all_flags;
1595 int i;
1596 long ret;
1597
1598 /* Test detection of known-good filter flags */
1599 for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
1600 int bits = 0;
1601
1602 flag = flags[i];
1603 /* Make sure the flag is a single bit! */
1604 while (flag) {
1605 if (flag & 0x1)
1606 bits ++;
1607 flag >>= 1;
1608 }
1609 ASSERT_EQ(1, bits);
1610 flag = flags[i];
1611
1612 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
1613 ASSERT_NE(ENOSYS, errno) {
1614 TH_LOG("Kernel does not support seccomp syscall!");
1615 }
1616 EXPECT_EQ(-1, ret);
1617 EXPECT_EQ(EFAULT, errno) {
1618 TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
1619 flag);
1620 }
1621
1622 all_flags |= flag;
1623 }
1624
1625 /* Test detection of all known-good filter flags */
1626 ret = seccomp(SECCOMP_SET_MODE_FILTER, all_flags, NULL);
1627 EXPECT_EQ(-1, ret);
1628 EXPECT_EQ(EFAULT, errno) {
1629 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
1630 all_flags);
1631 }
1632
1633 /* Test detection of an unknown filter flag */
1634 flag = -1;
1635 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
1636 EXPECT_EQ(-1, ret);
1637 EXPECT_EQ(EINVAL, errno) {
1638 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
1639 flag);
1640 }
1641
1642 /*
1643 * Test detection of an unknown filter flag that may simply need to be
1644 * added to this test
1645 */
1646 flag = flags[ARRAY_SIZE(flags) - 1] << 1;
1647 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
1648 EXPECT_EQ(-1, ret);
1649 EXPECT_EQ(EINVAL, errno) {
1650 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported! Does a new flag need to be added to this test?",
1651 flag);
1652 }
1653 }
1654
TEST(TSYNC_first)1655 TEST(TSYNC_first)
1656 {
1657 struct sock_filter filter[] = {
1658 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1659 };
1660 struct sock_fprog prog = {
1661 .len = (unsigned short)ARRAY_SIZE(filter),
1662 .filter = filter,
1663 };
1664 long ret;
1665
1666 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
1667 ASSERT_EQ(0, ret) {
1668 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1669 }
1670
1671 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
1672 &prog);
1673 ASSERT_NE(ENOSYS, errno) {
1674 TH_LOG("Kernel does not support seccomp syscall!");
1675 }
1676 EXPECT_EQ(0, ret) {
1677 TH_LOG("Could not install initial filter with TSYNC!");
1678 }
1679 }
1680
1681 #define TSYNC_SIBLINGS 2
1682 struct tsync_sibling {
1683 pthread_t tid;
1684 pid_t system_tid;
1685 sem_t *started;
1686 pthread_cond_t *cond;
1687 pthread_mutex_t *mutex;
1688 int diverge;
1689 int num_waits;
1690 struct sock_fprog *prog;
1691 struct __test_metadata *metadata;
1692 };
1693
FIXTURE_DATA(TSYNC)1694 FIXTURE_DATA(TSYNC) {
1695 struct sock_fprog root_prog, apply_prog;
1696 struct tsync_sibling sibling[TSYNC_SIBLINGS];
1697 sem_t started;
1698 pthread_cond_t cond;
1699 pthread_mutex_t mutex;
1700 int sibling_count;
1701 };
1702
FIXTURE_SETUP(TSYNC)1703 FIXTURE_SETUP(TSYNC)
1704 {
1705 struct sock_filter root_filter[] = {
1706 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1707 };
1708 struct sock_filter apply_filter[] = {
1709 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1710 offsetof(struct seccomp_data, nr)),
1711 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1712 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1713 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1714 };
1715
1716 memset(&self->root_prog, 0, sizeof(self->root_prog));
1717 memset(&self->apply_prog, 0, sizeof(self->apply_prog));
1718 memset(&self->sibling, 0, sizeof(self->sibling));
1719 self->root_prog.filter = malloc(sizeof(root_filter));
1720 ASSERT_NE(NULL, self->root_prog.filter);
1721 memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
1722 self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
1723
1724 self->apply_prog.filter = malloc(sizeof(apply_filter));
1725 ASSERT_NE(NULL, self->apply_prog.filter);
1726 memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
1727 self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
1728
1729 self->sibling_count = 0;
1730 pthread_mutex_init(&self->mutex, NULL);
1731 pthread_cond_init(&self->cond, NULL);
1732 sem_init(&self->started, 0, 0);
1733 self->sibling[0].tid = 0;
1734 self->sibling[0].cond = &self->cond;
1735 self->sibling[0].started = &self->started;
1736 self->sibling[0].mutex = &self->mutex;
1737 self->sibling[0].diverge = 0;
1738 self->sibling[0].num_waits = 1;
1739 self->sibling[0].prog = &self->root_prog;
1740 self->sibling[0].metadata = _metadata;
1741 self->sibling[1].tid = 0;
1742 self->sibling[1].cond = &self->cond;
1743 self->sibling[1].started = &self->started;
1744 self->sibling[1].mutex = &self->mutex;
1745 self->sibling[1].diverge = 0;
1746 self->sibling[1].prog = &self->root_prog;
1747 self->sibling[1].num_waits = 1;
1748 self->sibling[1].metadata = _metadata;
1749 }
1750
FIXTURE_TEARDOWN(TSYNC)1751 FIXTURE_TEARDOWN(TSYNC)
1752 {
1753 int sib = 0;
1754
1755 if (self->root_prog.filter)
1756 free(self->root_prog.filter);
1757 if (self->apply_prog.filter)
1758 free(self->apply_prog.filter);
1759
1760 for ( ; sib < self->sibling_count; ++sib) {
1761 struct tsync_sibling *s = &self->sibling[sib];
1762 void *status;
1763
1764 if (!s->tid)
1765 continue;
1766 if (pthread_kill(s->tid, 0)) {
1767 pthread_cancel(s->tid);
1768 pthread_join(s->tid, &status);
1769 }
1770 }
1771 pthread_mutex_destroy(&self->mutex);
1772 pthread_cond_destroy(&self->cond);
1773 sem_destroy(&self->started);
1774 }
1775
tsync_sibling(void * data)1776 void *tsync_sibling(void *data)
1777 {
1778 long ret = 0;
1779 struct tsync_sibling *me = data;
1780
1781 me->system_tid = syscall(__NR_gettid);
1782
1783 pthread_mutex_lock(me->mutex);
1784 if (me->diverge) {
1785 /* Just re-apply the root prog to fork the tree */
1786 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
1787 me->prog, 0, 0);
1788 }
1789 sem_post(me->started);
1790 /* Return outside of started so parent notices failures. */
1791 if (ret) {
1792 pthread_mutex_unlock(me->mutex);
1793 return (void *)SIBLING_EXIT_FAILURE;
1794 }
1795 do {
1796 pthread_cond_wait(me->cond, me->mutex);
1797 me->num_waits = me->num_waits - 1;
1798 } while (me->num_waits);
1799 pthread_mutex_unlock(me->mutex);
1800
1801 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
1802 if (!ret)
1803 return (void *)SIBLING_EXIT_NEWPRIVS;
1804 read(0, NULL, 0);
1805 return (void *)SIBLING_EXIT_UNKILLED;
1806 }
1807
tsync_start_sibling(struct tsync_sibling * sibling)1808 void tsync_start_sibling(struct tsync_sibling *sibling)
1809 {
1810 pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
1811 }
1812
TEST_F(TSYNC,siblings_fail_prctl)1813 TEST_F(TSYNC, siblings_fail_prctl)
1814 {
1815 long ret;
1816 void *status;
1817 struct sock_filter filter[] = {
1818 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1819 offsetof(struct seccomp_data, nr)),
1820 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
1821 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
1822 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1823 };
1824 struct sock_fprog prog = {
1825 .len = (unsigned short)ARRAY_SIZE(filter),
1826 .filter = filter,
1827 };
1828
1829 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1830 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1831 }
1832
1833 /* Check prctl failure detection by requesting sib 0 diverge. */
1834 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
1835 ASSERT_NE(ENOSYS, errno) {
1836 TH_LOG("Kernel does not support seccomp syscall!");
1837 }
1838 ASSERT_EQ(0, ret) {
1839 TH_LOG("setting filter failed");
1840 }
1841
1842 self->sibling[0].diverge = 1;
1843 tsync_start_sibling(&self->sibling[0]);
1844 tsync_start_sibling(&self->sibling[1]);
1845
1846 while (self->sibling_count < TSYNC_SIBLINGS) {
1847 sem_wait(&self->started);
1848 self->sibling_count++;
1849 }
1850
1851 /* Signal the threads to clean up*/
1852 pthread_mutex_lock(&self->mutex);
1853 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1854 TH_LOG("cond broadcast non-zero");
1855 }
1856 pthread_mutex_unlock(&self->mutex);
1857
1858 /* Ensure diverging sibling failed to call prctl. */
1859 pthread_join(self->sibling[0].tid, &status);
1860 EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
1861 pthread_join(self->sibling[1].tid, &status);
1862 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
1863 }
1864
TEST_F(TSYNC,two_siblings_with_ancestor)1865 TEST_F(TSYNC, two_siblings_with_ancestor)
1866 {
1867 long ret;
1868 void *status;
1869
1870 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1871 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1872 }
1873
1874 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
1875 ASSERT_NE(ENOSYS, errno) {
1876 TH_LOG("Kernel does not support seccomp syscall!");
1877 }
1878 ASSERT_EQ(0, ret) {
1879 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
1880 }
1881 tsync_start_sibling(&self->sibling[0]);
1882 tsync_start_sibling(&self->sibling[1]);
1883
1884 while (self->sibling_count < TSYNC_SIBLINGS) {
1885 sem_wait(&self->started);
1886 self->sibling_count++;
1887 }
1888
1889 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
1890 &self->apply_prog);
1891 ASSERT_EQ(0, ret) {
1892 TH_LOG("Could install filter on all threads!");
1893 }
1894 /* Tell the siblings to test the policy */
1895 pthread_mutex_lock(&self->mutex);
1896 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1897 TH_LOG("cond broadcast non-zero");
1898 }
1899 pthread_mutex_unlock(&self->mutex);
1900 /* Ensure they are both killed and don't exit cleanly. */
1901 pthread_join(self->sibling[0].tid, &status);
1902 EXPECT_EQ(0x0, (long)status);
1903 pthread_join(self->sibling[1].tid, &status);
1904 EXPECT_EQ(0x0, (long)status);
1905 }
1906
TEST_F(TSYNC,two_sibling_want_nnp)1907 TEST_F(TSYNC, two_sibling_want_nnp)
1908 {
1909 void *status;
1910
1911 /* start siblings before any prctl() operations */
1912 tsync_start_sibling(&self->sibling[0]);
1913 tsync_start_sibling(&self->sibling[1]);
1914 while (self->sibling_count < TSYNC_SIBLINGS) {
1915 sem_wait(&self->started);
1916 self->sibling_count++;
1917 }
1918
1919 /* Tell the siblings to test no policy */
1920 pthread_mutex_lock(&self->mutex);
1921 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1922 TH_LOG("cond broadcast non-zero");
1923 }
1924 pthread_mutex_unlock(&self->mutex);
1925
1926 /* Ensure they are both upset about lacking nnp. */
1927 pthread_join(self->sibling[0].tid, &status);
1928 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
1929 pthread_join(self->sibling[1].tid, &status);
1930 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
1931 }
1932
TEST_F(TSYNC,two_siblings_with_no_filter)1933 TEST_F(TSYNC, two_siblings_with_no_filter)
1934 {
1935 long ret;
1936 void *status;
1937
1938 /* start siblings before any prctl() operations */
1939 tsync_start_sibling(&self->sibling[0]);
1940 tsync_start_sibling(&self->sibling[1]);
1941 while (self->sibling_count < TSYNC_SIBLINGS) {
1942 sem_wait(&self->started);
1943 self->sibling_count++;
1944 }
1945
1946 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1947 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1948 }
1949
1950 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
1951 &self->apply_prog);
1952 ASSERT_NE(ENOSYS, errno) {
1953 TH_LOG("Kernel does not support seccomp syscall!");
1954 }
1955 ASSERT_EQ(0, ret) {
1956 TH_LOG("Could install filter on all threads!");
1957 }
1958
1959 /* Tell the siblings to test the policy */
1960 pthread_mutex_lock(&self->mutex);
1961 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1962 TH_LOG("cond broadcast non-zero");
1963 }
1964 pthread_mutex_unlock(&self->mutex);
1965
1966 /* Ensure they are both killed and don't exit cleanly. */
1967 pthread_join(self->sibling[0].tid, &status);
1968 EXPECT_EQ(0x0, (long)status);
1969 pthread_join(self->sibling[1].tid, &status);
1970 EXPECT_EQ(0x0, (long)status);
1971 }
1972
TEST_F(TSYNC,two_siblings_with_one_divergence)1973 TEST_F(TSYNC, two_siblings_with_one_divergence)
1974 {
1975 long ret;
1976 void *status;
1977
1978 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1979 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1980 }
1981
1982 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
1983 ASSERT_NE(ENOSYS, errno) {
1984 TH_LOG("Kernel does not support seccomp syscall!");
1985 }
1986 ASSERT_EQ(0, ret) {
1987 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
1988 }
1989 self->sibling[0].diverge = 1;
1990 tsync_start_sibling(&self->sibling[0]);
1991 tsync_start_sibling(&self->sibling[1]);
1992
1993 while (self->sibling_count < TSYNC_SIBLINGS) {
1994 sem_wait(&self->started);
1995 self->sibling_count++;
1996 }
1997
1998 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
1999 &self->apply_prog);
2000 ASSERT_EQ(self->sibling[0].system_tid, ret) {
2001 TH_LOG("Did not fail on diverged sibling.");
2002 }
2003
2004 /* Wake the threads */
2005 pthread_mutex_lock(&self->mutex);
2006 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2007 TH_LOG("cond broadcast non-zero");
2008 }
2009 pthread_mutex_unlock(&self->mutex);
2010
2011 /* Ensure they are both unkilled. */
2012 pthread_join(self->sibling[0].tid, &status);
2013 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2014 pthread_join(self->sibling[1].tid, &status);
2015 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2016 }
2017
TEST_F(TSYNC,two_siblings_not_under_filter)2018 TEST_F(TSYNC, two_siblings_not_under_filter)
2019 {
2020 long ret, sib;
2021 void *status;
2022
2023 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2024 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2025 }
2026
2027 /*
2028 * Sibling 0 will have its own seccomp policy
2029 * and Sibling 1 will not be under seccomp at
2030 * all. Sibling 1 will enter seccomp and 0
2031 * will cause failure.
2032 */
2033 self->sibling[0].diverge = 1;
2034 tsync_start_sibling(&self->sibling[0]);
2035 tsync_start_sibling(&self->sibling[1]);
2036
2037 while (self->sibling_count < TSYNC_SIBLINGS) {
2038 sem_wait(&self->started);
2039 self->sibling_count++;
2040 }
2041
2042 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2043 ASSERT_NE(ENOSYS, errno) {
2044 TH_LOG("Kernel does not support seccomp syscall!");
2045 }
2046 ASSERT_EQ(0, ret) {
2047 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2048 }
2049
2050 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2051 &self->apply_prog);
2052 ASSERT_EQ(ret, self->sibling[0].system_tid) {
2053 TH_LOG("Did not fail on diverged sibling.");
2054 }
2055 sib = 1;
2056 if (ret == self->sibling[0].system_tid)
2057 sib = 0;
2058
2059 pthread_mutex_lock(&self->mutex);
2060
2061 /* Increment the other siblings num_waits so we can clean up
2062 * the one we just saw.
2063 */
2064 self->sibling[!sib].num_waits += 1;
2065
2066 /* Signal the thread to clean up*/
2067 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2068 TH_LOG("cond broadcast non-zero");
2069 }
2070 pthread_mutex_unlock(&self->mutex);
2071 pthread_join(self->sibling[sib].tid, &status);
2072 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2073 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2074 while (!kill(self->sibling[sib].system_tid, 0))
2075 sleep(0.1);
2076 /* Switch to the remaining sibling */
2077 sib = !sib;
2078
2079 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2080 &self->apply_prog);
2081 ASSERT_EQ(0, ret) {
2082 TH_LOG("Expected the remaining sibling to sync");
2083 };
2084
2085 pthread_mutex_lock(&self->mutex);
2086
2087 /* If remaining sibling didn't have a chance to wake up during
2088 * the first broadcast, manually reduce the num_waits now.
2089 */
2090 if (self->sibling[sib].num_waits > 1)
2091 self->sibling[sib].num_waits = 1;
2092 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2093 TH_LOG("cond broadcast non-zero");
2094 }
2095 pthread_mutex_unlock(&self->mutex);
2096 pthread_join(self->sibling[sib].tid, &status);
2097 EXPECT_EQ(0, (long)status);
2098 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2099 while (!kill(self->sibling[sib].system_tid, 0))
2100 sleep(0.1);
2101
2102 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2103 &self->apply_prog);
2104 ASSERT_EQ(0, ret); /* just us chickens */
2105 }
2106
2107 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
TEST(syscall_restart)2108 TEST(syscall_restart)
2109 {
2110 long ret;
2111 unsigned long msg;
2112 pid_t child_pid;
2113 int pipefd[2];
2114 int status;
2115 siginfo_t info = { };
2116 struct sock_filter filter[] = {
2117 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2118 offsetof(struct seccomp_data, nr)),
2119
2120 #ifdef __NR_sigreturn
2121 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0),
2122 #endif
2123 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
2124 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
2125 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
2126 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0),
2127 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2128
2129 /* Allow __NR_write for easy logging. */
2130 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2131 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2132 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2133 /* The nanosleep jump target. */
2134 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2135 /* The restart_syscall jump target. */
2136 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
2137 };
2138 struct sock_fprog prog = {
2139 .len = (unsigned short)ARRAY_SIZE(filter),
2140 .filter = filter,
2141 };
2142 #if defined(__arm__)
2143 struct utsname utsbuf;
2144 #endif
2145
2146 ASSERT_EQ(0, pipe(pipefd));
2147
2148 child_pid = fork();
2149 ASSERT_LE(0, child_pid);
2150 if (child_pid == 0) {
2151 /* Child uses EXPECT not ASSERT to deliver status correctly. */
2152 char buf = ' ';
2153 struct timespec timeout = { };
2154
2155 /* Attach parent as tracer and stop. */
2156 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2157 EXPECT_EQ(0, raise(SIGSTOP));
2158
2159 EXPECT_EQ(0, close(pipefd[1]));
2160
2161 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2162 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2163 }
2164
2165 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2166 EXPECT_EQ(0, ret) {
2167 TH_LOG("Failed to install filter!");
2168 }
2169
2170 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2171 TH_LOG("Failed to read() sync from parent");
2172 }
2173 EXPECT_EQ('.', buf) {
2174 TH_LOG("Failed to get sync data from read()");
2175 }
2176
2177 /* Start nanosleep to be interrupted. */
2178 timeout.tv_sec = 1;
2179 errno = 0;
2180 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2181 TH_LOG("Call to nanosleep() failed (errno %d)", errno);
2182 }
2183
2184 /* Read final sync from parent. */
2185 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2186 TH_LOG("Failed final read() from parent");
2187 }
2188 EXPECT_EQ('!', buf) {
2189 TH_LOG("Failed to get final data from read()");
2190 }
2191
2192 /* Directly report the status of our test harness results. */
2193 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2194 : EXIT_FAILURE);
2195 }
2196 EXPECT_EQ(0, close(pipefd[0]));
2197
2198 /* Attach to child, setup options, and release. */
2199 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2200 ASSERT_EQ(true, WIFSTOPPED(status));
2201 ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2202 PTRACE_O_TRACESECCOMP));
2203 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2204 ASSERT_EQ(1, write(pipefd[1], ".", 1));
2205
2206 /* Wait for nanosleep() to start. */
2207 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2208 ASSERT_EQ(true, WIFSTOPPED(status));
2209 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2210 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2211 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2212 ASSERT_EQ(0x100, msg);
2213 EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
2214
2215 /* Might as well check siginfo for sanity while we're here. */
2216 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2217 ASSERT_EQ(SIGTRAP, info.si_signo);
2218 ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2219 EXPECT_EQ(0, info.si_errno);
2220 EXPECT_EQ(getuid(), info.si_uid);
2221 /* Verify signal delivery came from child (seccomp-triggered). */
2222 EXPECT_EQ(child_pid, info.si_pid);
2223
2224 /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
2225 ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2226 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2227 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2228 ASSERT_EQ(true, WIFSTOPPED(status));
2229 ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
2230 /* Verify signal delivery came from parent now. */
2231 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2232 EXPECT_EQ(getpid(), info.si_pid);
2233
2234 /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
2235 ASSERT_EQ(0, kill(child_pid, SIGCONT));
2236 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2237 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2238 ASSERT_EQ(true, WIFSTOPPED(status));
2239 ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2240 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2241
2242 /* Wait for restart_syscall() to start. */
2243 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2244 ASSERT_EQ(true, WIFSTOPPED(status));
2245 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2246 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2247 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2248
2249 ASSERT_EQ(0x200, msg);
2250 ret = get_syscall(_metadata, child_pid);
2251 #if defined(__arm__)
2252 /*
2253 * FIXME:
2254 * - native ARM registers do NOT expose true syscall.
2255 * - compat ARM registers on ARM64 DO expose true syscall.
2256 */
2257 ASSERT_EQ(0, uname(&utsbuf));
2258 if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2259 EXPECT_EQ(__NR_nanosleep, ret);
2260 } else
2261 #endif
2262 {
2263 EXPECT_EQ(__NR_restart_syscall, ret);
2264 }
2265
2266 /* Write again to end test. */
2267 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2268 ASSERT_EQ(1, write(pipefd[1], "!", 1));
2269 EXPECT_EQ(0, close(pipefd[1]));
2270
2271 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2272 if (WIFSIGNALED(status) || WEXITSTATUS(status))
2273 _metadata->passed = 0;
2274 }
2275
2276 /*
2277 * TODO:
2278 * - add microbenchmarks
2279 * - expand NNP testing
2280 * - better arch-specific TRACE and TRAP handlers.
2281 * - endianness checking when appropriate
2282 * - 64-bit arg prodding
2283 * - arch value testing (x86 modes especially)
2284 * - ...
2285 */
2286
2287 TEST_HARNESS_MAIN
2288