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Merge tag 'seccomp-v4.14-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees...
[linux-stable.git] / tools / testing / selftests / seccomp / seccomp_bpf.c
blob67c3e276430363754e8354dfb2bb7f2485a26c66
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 <sys/types.h>
9 #include <asm/siginfo.h>
10 #define __have_siginfo_t 1
11 #define __have_sigval_t 1
12 #define __have_sigevent_t 1
13
14 #include <errno.h>
15 #include <linux/filter.h>
16 #include <sys/prctl.h>
17 #include <sys/ptrace.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 "../kselftest_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_ALLOW
72 struct seccomp_data {
73 int nr;
74 __u32 arch;
75 __u64 instruction_pointer;
76 __u64 args[6];
77 };
78 #endif
79
80 #ifndef SECCOMP_RET_KILL_PROCESS
81 #define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process */
82 #define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread */
83 #endif
84 #ifndef SECCOMP_RET_KILL
85 #define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD
86 #define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
87 #define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
88 #define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
89 #define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
90 #endif
91 #ifndef SECCOMP_RET_LOG
92 #define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */
93 #endif
94
95 #ifndef __NR_seccomp
96 # if defined(__i386__)
97 # define __NR_seccomp 354
98 # elif defined(__x86_64__)
99 # define __NR_seccomp 317
100 # elif defined(__arm__)
101 # define __NR_seccomp 383
102 # elif defined(__aarch64__)
103 # define __NR_seccomp 277
104 # elif defined(__hppa__)
105 # define __NR_seccomp 338
106 # elif defined(__powerpc__)
107 # define __NR_seccomp 358
108 # elif defined(__s390__)
109 # define __NR_seccomp 348
110 # else
111 # warning "seccomp syscall number unknown for this architecture"
112 # define __NR_seccomp 0xffff
113 # endif
114 #endif
115
116 #ifndef SECCOMP_SET_MODE_STRICT
117 #define SECCOMP_SET_MODE_STRICT 0
118 #endif
119
120 #ifndef SECCOMP_SET_MODE_FILTER
121 #define SECCOMP_SET_MODE_FILTER 1
122 #endif
123
124 #ifndef SECCOMP_GET_ACTION_AVAIL
125 #define SECCOMP_GET_ACTION_AVAIL 2
126 #endif
127
128 #ifndef SECCOMP_FILTER_FLAG_TSYNC
129 #define SECCOMP_FILTER_FLAG_TSYNC 1
130 #endif
131
132 #ifndef SECCOMP_FILTER_FLAG_LOG
133 #define SECCOMP_FILTER_FLAG_LOG 2
134 #endif
135
136 #ifndef seccomp
137 int seccomp(unsigned int op, unsigned int flags, void *args)
138 {
139 errno = 0;
140 return syscall(__NR_seccomp, op, flags, args);
141 }
142 #endif
143
144 #if __BYTE_ORDER == __LITTLE_ENDIAN
145 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
146 #elif __BYTE_ORDER == __BIG_ENDIAN
147 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
148 #else
149 #error "wut? Unknown __BYTE_ORDER?!"
150 #endif
151
152 #define SIBLING_EXIT_UNKILLED 0xbadbeef
153 #define SIBLING_EXIT_FAILURE 0xbadface
154 #define SIBLING_EXIT_NEWPRIVS 0xbadfeed
155
156 TEST(mode_strict_support)
157 {
158 long ret;
159
160 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
161 ASSERT_EQ(0, ret) {
162 TH_LOG("Kernel does not support CONFIG_SECCOMP");
163 }
164 syscall(__NR_exit, 0);
165 }
166
167 TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
168 {
169 long ret;
170
171 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
172 ASSERT_EQ(0, ret) {
173 TH_LOG("Kernel does not support CONFIG_SECCOMP");
174 }
175 syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
176 NULL, NULL, NULL);
177 EXPECT_FALSE(true) {
178 TH_LOG("Unreachable!");
179 }
180 }
181
182 /* Note! This doesn't test no new privs behavior */
183 TEST(no_new_privs_support)
184 {
185 long ret;
186
187 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
188 EXPECT_EQ(0, ret) {
189 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
190 }
191 }
192
193 /* Tests kernel support by checking for a copy_from_user() fault on NULL. */
194 TEST(mode_filter_support)
195 {
196 long ret;
197
198 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
199 ASSERT_EQ(0, ret) {
200 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
201 }
202 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
203 EXPECT_EQ(-1, ret);
204 EXPECT_EQ(EFAULT, errno) {
205 TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
206 }
207 }
208
209 TEST(mode_filter_without_nnp)
210 {
211 struct sock_filter filter[] = {
212 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
213 };
214 struct sock_fprog prog = {
215 .len = (unsigned short)ARRAY_SIZE(filter),
216 .filter = filter,
217 };
218 long ret;
219
220 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
221 ASSERT_LE(0, ret) {
222 TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
223 }
224 errno = 0;
225 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
226 /* Succeeds with CAP_SYS_ADMIN, fails without */
227 /* TODO(wad) check caps not euid */
228 if (geteuid()) {
229 EXPECT_EQ(-1, ret);
230 EXPECT_EQ(EACCES, errno);
231 } else {
232 EXPECT_EQ(0, ret);
233 }
234 }
235
236 #define MAX_INSNS_PER_PATH 32768
237
238 TEST(filter_size_limits)
239 {
240 int i;
241 int count = BPF_MAXINSNS + 1;
242 struct sock_filter allow[] = {
243 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
244 };
245 struct sock_filter *filter;
246 struct sock_fprog prog = { };
247 long ret;
248
249 filter = calloc(count, sizeof(*filter));
250 ASSERT_NE(NULL, filter);
251
252 for (i = 0; i < count; i++)
253 filter[i] = allow[0];
254
255 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
256 ASSERT_EQ(0, ret);
257
258 prog.filter = filter;
259 prog.len = count;
260
261 /* Too many filter instructions in a single filter. */
262 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
263 ASSERT_NE(0, ret) {
264 TH_LOG("Installing %d insn filter was allowed", prog.len);
265 }
266
267 /* One less is okay, though. */
268 prog.len -= 1;
269 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
270 ASSERT_EQ(0, ret) {
271 TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
272 }
273 }
274
275 TEST(filter_chain_limits)
276 {
277 int i;
278 int count = BPF_MAXINSNS;
279 struct sock_filter allow[] = {
280 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
281 };
282 struct sock_filter *filter;
283 struct sock_fprog prog = { };
284 long ret;
285
286 filter = calloc(count, sizeof(*filter));
287 ASSERT_NE(NULL, filter);
288
289 for (i = 0; i < count; i++)
290 filter[i] = allow[0];
291
292 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
293 ASSERT_EQ(0, ret);
294
295 prog.filter = filter;
296 prog.len = 1;
297
298 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
299 ASSERT_EQ(0, ret);
300
301 prog.len = count;
302
303 /* Too many total filter instructions. */
304 for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
305 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
306 if (ret != 0)
307 break;
308 }
309 ASSERT_NE(0, ret) {
310 TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
311 i, count, i * (count + 4));
312 }
313 }
314
315 TEST(mode_filter_cannot_move_to_strict)
316 {
317 struct sock_filter filter[] = {
318 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
319 };
320 struct sock_fprog prog = {
321 .len = (unsigned short)ARRAY_SIZE(filter),
322 .filter = filter,
323 };
324 long ret;
325
326 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
327 ASSERT_EQ(0, ret);
328
329 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
330 ASSERT_EQ(0, ret);
331
332 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
333 EXPECT_EQ(-1, ret);
334 EXPECT_EQ(EINVAL, errno);
335 }
336
337
338 TEST(mode_filter_get_seccomp)
339 {
340 struct sock_filter filter[] = {
341 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
342 };
343 struct sock_fprog prog = {
344 .len = (unsigned short)ARRAY_SIZE(filter),
345 .filter = filter,
346 };
347 long ret;
348
349 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
350 ASSERT_EQ(0, ret);
351
352 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
353 EXPECT_EQ(0, ret);
354
355 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
356 ASSERT_EQ(0, ret);
357
358 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
359 EXPECT_EQ(2, ret);
360 }
361
362
363 TEST(ALLOW_all)
364 {
365 struct sock_filter filter[] = {
366 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
367 };
368 struct sock_fprog prog = {
369 .len = (unsigned short)ARRAY_SIZE(filter),
370 .filter = filter,
371 };
372 long ret;
373
374 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
375 ASSERT_EQ(0, ret);
376
377 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
378 ASSERT_EQ(0, ret);
379 }
380
381 TEST(empty_prog)
382 {
383 struct sock_filter filter[] = {
384 };
385 struct sock_fprog prog = {
386 .len = (unsigned short)ARRAY_SIZE(filter),
387 .filter = filter,
388 };
389 long ret;
390
391 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
392 ASSERT_EQ(0, ret);
393
394 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
395 EXPECT_EQ(-1, ret);
396 EXPECT_EQ(EINVAL, errno);
397 }
398
399 TEST(log_all)
400 {
401 struct sock_filter filter[] = {
402 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
403 };
404 struct sock_fprog prog = {
405 .len = (unsigned short)ARRAY_SIZE(filter),
406 .filter = filter,
407 };
408 long ret;
409 pid_t parent = getppid();
410
411 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
412 ASSERT_EQ(0, ret);
413
414 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
415 ASSERT_EQ(0, ret);
416
417 /* getppid() should succeed and be logged (no check for logging) */
418 EXPECT_EQ(parent, syscall(__NR_getppid));
419 }
420
421 TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
422 {
423 struct sock_filter filter[] = {
424 BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
425 };
426 struct sock_fprog prog = {
427 .len = (unsigned short)ARRAY_SIZE(filter),
428 .filter = filter,
429 };
430 long ret;
431
432 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
433 ASSERT_EQ(0, ret);
434
435 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
436 ASSERT_EQ(0, ret);
437 EXPECT_EQ(0, syscall(__NR_getpid)) {
438 TH_LOG("getpid() shouldn't ever return");
439 }
440 }
441
442 /* return code >= 0x80000000 is unused. */
443 TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
444 {
445 struct sock_filter filter[] = {
446 BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
447 };
448 struct sock_fprog prog = {
449 .len = (unsigned short)ARRAY_SIZE(filter),
450 .filter = filter,
451 };
452 long ret;
453
454 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
455 ASSERT_EQ(0, ret);
456
457 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
458 ASSERT_EQ(0, ret);
459 EXPECT_EQ(0, syscall(__NR_getpid)) {
460 TH_LOG("getpid() shouldn't ever return");
461 }
462 }
463
464 TEST_SIGNAL(KILL_all, SIGSYS)
465 {
466 struct sock_filter filter[] = {
467 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
468 };
469 struct sock_fprog prog = {
470 .len = (unsigned short)ARRAY_SIZE(filter),
471 .filter = filter,
472 };
473 long ret;
474
475 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
476 ASSERT_EQ(0, ret);
477
478 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
479 ASSERT_EQ(0, ret);
480 }
481
482 TEST_SIGNAL(KILL_one, SIGSYS)
483 {
484 struct sock_filter filter[] = {
485 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
486 offsetof(struct seccomp_data, nr)),
487 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
488 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
489 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
490 };
491 struct sock_fprog prog = {
492 .len = (unsigned short)ARRAY_SIZE(filter),
493 .filter = filter,
494 };
495 long ret;
496 pid_t parent = getppid();
497
498 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
499 ASSERT_EQ(0, ret);
500
501 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
502 ASSERT_EQ(0, ret);
503
504 EXPECT_EQ(parent, syscall(__NR_getppid));
505 /* getpid() should never return. */
506 EXPECT_EQ(0, syscall(__NR_getpid));
507 }
508
509 TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
510 {
511 void *fatal_address;
512 struct sock_filter filter[] = {
513 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
514 offsetof(struct seccomp_data, nr)),
515 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0),
516 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
517 /* Only both with lower 32-bit for now. */
518 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
519 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
520 (unsigned long)&fatal_address, 0, 1),
521 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
522 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
523 };
524 struct sock_fprog prog = {
525 .len = (unsigned short)ARRAY_SIZE(filter),
526 .filter = filter,
527 };
528 long ret;
529 pid_t parent = getppid();
530 struct tms timebuf;
531 clock_t clock = times(&timebuf);
532
533 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
534 ASSERT_EQ(0, ret);
535
536 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
537 ASSERT_EQ(0, ret);
538
539 EXPECT_EQ(parent, syscall(__NR_getppid));
540 EXPECT_LE(clock, syscall(__NR_times, &timebuf));
541 /* times() should never return. */
542 EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
543 }
544
545 TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
546 {
547 #ifndef __NR_mmap2
548 int sysno = __NR_mmap;
549 #else
550 int sysno = __NR_mmap2;
551 #endif
552 struct sock_filter filter[] = {
553 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
554 offsetof(struct seccomp_data, nr)),
555 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0),
556 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
557 /* Only both with lower 32-bit for now. */
558 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
559 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
560 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
561 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
562 };
563 struct sock_fprog prog = {
564 .len = (unsigned short)ARRAY_SIZE(filter),
565 .filter = filter,
566 };
567 long ret;
568 pid_t parent = getppid();
569 int fd;
570 void *map1, *map2;
571 int page_size = sysconf(_SC_PAGESIZE);
572
573 ASSERT_LT(0, page_size);
574
575 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
576 ASSERT_EQ(0, ret);
577
578 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
579 ASSERT_EQ(0, ret);
580
581 fd = open("/dev/zero", O_RDONLY);
582 ASSERT_NE(-1, fd);
583
584 EXPECT_EQ(parent, syscall(__NR_getppid));
585 map1 = (void *)syscall(sysno,
586 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
587 EXPECT_NE(MAP_FAILED, map1);
588 /* mmap2() should never return. */
589 map2 = (void *)syscall(sysno,
590 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
591 EXPECT_EQ(MAP_FAILED, map2);
592
593 /* The test failed, so clean up the resources. */
594 munmap(map1, page_size);
595 munmap(map2, page_size);
596 close(fd);
597 }
598
599 /* This is a thread task to die via seccomp filter violation. */
600 void *kill_thread(void *data)
601 {
602 bool die = (bool)data;
603
604 if (die) {
605 prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
606 return (void *)SIBLING_EXIT_FAILURE;
607 }
608
609 return (void *)SIBLING_EXIT_UNKILLED;
610 }
611
612 /* Prepare a thread that will kill itself or both of us. */
613 void kill_thread_or_group(struct __test_metadata *_metadata, bool kill_process)
614 {
615 pthread_t thread;
616 void *status;
617 /* Kill only when calling __NR_prctl. */
618 struct sock_filter filter_thread[] = {
619 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
620 offsetof(struct seccomp_data, nr)),
621 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
622 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
623 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
624 };
625 struct sock_fprog prog_thread = {
626 .len = (unsigned short)ARRAY_SIZE(filter_thread),
627 .filter = filter_thread,
628 };
629 struct sock_filter filter_process[] = {
630 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
631 offsetof(struct seccomp_data, nr)),
632 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
633 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_PROCESS),
634 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
635 };
636 struct sock_fprog prog_process = {
637 .len = (unsigned short)ARRAY_SIZE(filter_process),
638 .filter = filter_process,
639 };
640
641 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
642 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
643 }
644
645 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
646 kill_process ? &prog_process : &prog_thread));
647
648 /*
649 * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
650 * flag cannot be downgraded by a new filter.
651 */
652 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
653
654 /* Start a thread that will exit immediately. */
655 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
656 ASSERT_EQ(0, pthread_join(thread, &status));
657 ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
658
659 /* Start a thread that will die immediately. */
660 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
661 ASSERT_EQ(0, pthread_join(thread, &status));
662 ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
663
664 /*
665 * If we get here, only the spawned thread died. Let the parent know
666 * the whole process didn't die (i.e. this thread, the spawner,
667 * stayed running).
668 */
669 exit(42);
670 }
671
672 TEST(KILL_thread)
673 {
674 int status;
675 pid_t child_pid;
676
677 child_pid = fork();
678 ASSERT_LE(0, child_pid);
679 if (child_pid == 0) {
680 kill_thread_or_group(_metadata, false);
681 _exit(38);
682 }
683
684 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
685
686 /* If only the thread was killed, we'll see exit 42. */
687 ASSERT_TRUE(WIFEXITED(status));
688 ASSERT_EQ(42, WEXITSTATUS(status));
689 }
690
691 TEST(KILL_process)
692 {
693 int status;
694 pid_t child_pid;
695
696 child_pid = fork();
697 ASSERT_LE(0, child_pid);
698 if (child_pid == 0) {
699 kill_thread_or_group(_metadata, true);
700 _exit(38);
701 }
702
703 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
704
705 /* If the entire process was killed, we'll see SIGSYS. */
706 ASSERT_TRUE(WIFSIGNALED(status));
707 ASSERT_EQ(SIGSYS, WTERMSIG(status));
708 }
709
710 /* TODO(wad) add 64-bit versus 32-bit arg tests. */
711 TEST(arg_out_of_range)
712 {
713 struct sock_filter filter[] = {
714 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
715 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
716 };
717 struct sock_fprog prog = {
718 .len = (unsigned short)ARRAY_SIZE(filter),
719 .filter = filter,
720 };
721 long ret;
722
723 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
724 ASSERT_EQ(0, ret);
725
726 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
727 EXPECT_EQ(-1, ret);
728 EXPECT_EQ(EINVAL, errno);
729 }
730
731 #define ERRNO_FILTER(name, errno) \
732 struct sock_filter _read_filter_##name[] = { \
733 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, \
734 offsetof(struct seccomp_data, nr)), \
735 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), \
736 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | errno), \
737 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), \
738 }; \
739 struct sock_fprog prog_##name = { \
740 .len = (unsigned short)ARRAY_SIZE(_read_filter_##name), \
741 .filter = _read_filter_##name, \
742 }
743
744 /* Make sure basic errno values are correctly passed through a filter. */
745 TEST(ERRNO_valid)
746 {
747 ERRNO_FILTER(valid, E2BIG);
748 long ret;
749 pid_t parent = getppid();
750
751 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
752 ASSERT_EQ(0, ret);
753
754 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_valid);
755 ASSERT_EQ(0, ret);
756
757 EXPECT_EQ(parent, syscall(__NR_getppid));
758 EXPECT_EQ(-1, read(0, NULL, 0));
759 EXPECT_EQ(E2BIG, errno);
760 }
761
762 /* Make sure an errno of zero is correctly handled by the arch code. */
763 TEST(ERRNO_zero)
764 {
765 ERRNO_FILTER(zero, 0);
766 long ret;
767 pid_t parent = getppid();
768
769 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
770 ASSERT_EQ(0, ret);
771
772 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_zero);
773 ASSERT_EQ(0, ret);
774
775 EXPECT_EQ(parent, syscall(__NR_getppid));
776 /* "errno" of 0 is ok. */
777 EXPECT_EQ(0, read(0, NULL, 0));
778 }
779
780 /*
781 * The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
782 * This tests that the errno value gets capped correctly, fixed by
783 * 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
784 */
785 TEST(ERRNO_capped)
786 {
787 ERRNO_FILTER(capped, 4096);
788 long ret;
789 pid_t parent = getppid();
790
791 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
792 ASSERT_EQ(0, ret);
793
794 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_capped);
795 ASSERT_EQ(0, ret);
796
797 EXPECT_EQ(parent, syscall(__NR_getppid));
798 EXPECT_EQ(-1, read(0, NULL, 0));
799 EXPECT_EQ(4095, errno);
800 }
801
802 /*
803 * Filters are processed in reverse order: last applied is executed first.
804 * Since only the SECCOMP_RET_ACTION mask is tested for return values, the
805 * SECCOMP_RET_DATA mask results will follow the most recently applied
806 * matching filter return (and not the lowest or highest value).
807 */
808 TEST(ERRNO_order)
809 {
810 ERRNO_FILTER(first, 11);
811 ERRNO_FILTER(second, 13);
812 ERRNO_FILTER(third, 12);
813 long ret;
814 pid_t parent = getppid();
815
816 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
817 ASSERT_EQ(0, ret);
818
819 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_first);
820 ASSERT_EQ(0, ret);
821
822 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_second);
823 ASSERT_EQ(0, ret);
824
825 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_third);
826 ASSERT_EQ(0, ret);
827
828 EXPECT_EQ(parent, syscall(__NR_getppid));
829 EXPECT_EQ(-1, read(0, NULL, 0));
830 EXPECT_EQ(12, errno);
831 }
832
833 FIXTURE_DATA(TRAP) {
834 struct sock_fprog prog;
835 };
836
837 FIXTURE_SETUP(TRAP)
838 {
839 struct sock_filter filter[] = {
840 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
841 offsetof(struct seccomp_data, nr)),
842 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
843 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
844 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
845 };
846
847 memset(&self->prog, 0, sizeof(self->prog));
848 self->prog.filter = malloc(sizeof(filter));
849 ASSERT_NE(NULL, self->prog.filter);
850 memcpy(self->prog.filter, filter, sizeof(filter));
851 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
852 }
853
854 FIXTURE_TEARDOWN(TRAP)
855 {
856 if (self->prog.filter)
857 free(self->prog.filter);
858 }
859
860 TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
861 {
862 long ret;
863
864 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
865 ASSERT_EQ(0, ret);
866
867 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
868 ASSERT_EQ(0, ret);
869 syscall(__NR_getpid);
870 }
871
872 /* Ensure that SIGSYS overrides SIG_IGN */
873 TEST_F_SIGNAL(TRAP, ign, SIGSYS)
874 {
875 long ret;
876
877 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
878 ASSERT_EQ(0, ret);
879
880 signal(SIGSYS, SIG_IGN);
881
882 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
883 ASSERT_EQ(0, ret);
884 syscall(__NR_getpid);
885 }
886
887 static struct siginfo TRAP_info;
888 static volatile int TRAP_nr;
889 static void TRAP_action(int nr, siginfo_t *info, void *void_context)
890 {
891 memcpy(&TRAP_info, info, sizeof(TRAP_info));
892 TRAP_nr = nr;
893 }
894
895 TEST_F(TRAP, handler)
896 {
897 int ret, test;
898 struct sigaction act;
899 sigset_t mask;
900
901 memset(&act, 0, sizeof(act));
902 sigemptyset(&mask);
903 sigaddset(&mask, SIGSYS);
904
905 act.sa_sigaction = &TRAP_action;
906 act.sa_flags = SA_SIGINFO;
907 ret = sigaction(SIGSYS, &act, NULL);
908 ASSERT_EQ(0, ret) {
909 TH_LOG("sigaction failed");
910 }
911 ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
912 ASSERT_EQ(0, ret) {
913 TH_LOG("sigprocmask failed");
914 }
915
916 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
917 ASSERT_EQ(0, ret);
918 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
919 ASSERT_EQ(0, ret);
920 TRAP_nr = 0;
921 memset(&TRAP_info, 0, sizeof(TRAP_info));
922 /* Expect the registers to be rolled back. (nr = error) may vary
923 * based on arch. */
924 ret = syscall(__NR_getpid);
925 /* Silence gcc warning about volatile. */
926 test = TRAP_nr;
927 EXPECT_EQ(SIGSYS, test);
928 struct local_sigsys {
929 void *_call_addr; /* calling user insn */
930 int _syscall; /* triggering system call number */
931 unsigned int _arch; /* AUDIT_ARCH_* of syscall */
932 } *sigsys = (struct local_sigsys *)
933 #ifdef si_syscall
934 &(TRAP_info.si_call_addr);
935 #else
936 &TRAP_info.si_pid;
937 #endif
938 EXPECT_EQ(__NR_getpid, sigsys->_syscall);
939 /* Make sure arch is non-zero. */
940 EXPECT_NE(0, sigsys->_arch);
941 EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
942 }
943
944 FIXTURE_DATA(precedence) {
945 struct sock_fprog allow;
946 struct sock_fprog log;
947 struct sock_fprog trace;
948 struct sock_fprog error;
949 struct sock_fprog trap;
950 struct sock_fprog kill;
951 };
952
953 FIXTURE_SETUP(precedence)
954 {
955 struct sock_filter allow_insns[] = {
956 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
957 };
958 struct sock_filter log_insns[] = {
959 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
960 offsetof(struct seccomp_data, nr)),
961 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
962 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
963 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
964 };
965 struct sock_filter trace_insns[] = {
966 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
967 offsetof(struct seccomp_data, nr)),
968 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
969 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
970 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE),
971 };
972 struct sock_filter error_insns[] = {
973 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
974 offsetof(struct seccomp_data, nr)),
975 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
976 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
977 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO),
978 };
979 struct sock_filter trap_insns[] = {
980 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
981 offsetof(struct seccomp_data, nr)),
982 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
983 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
984 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
985 };
986 struct sock_filter kill_insns[] = {
987 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
988 offsetof(struct seccomp_data, nr)),
989 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
990 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
991 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
992 };
993
994 memset(self, 0, sizeof(*self));
995 #define FILTER_ALLOC(_x) \
996 self->_x.filter = malloc(sizeof(_x##_insns)); \
997 ASSERT_NE(NULL, self->_x.filter); \
998 memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
999 self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
1000 FILTER_ALLOC(allow);
1001 FILTER_ALLOC(log);
1002 FILTER_ALLOC(trace);
1003 FILTER_ALLOC(error);
1004 FILTER_ALLOC(trap);
1005 FILTER_ALLOC(kill);
1006 }
1007
1008 FIXTURE_TEARDOWN(precedence)
1009 {
1010 #define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
1011 FILTER_FREE(allow);
1012 FILTER_FREE(log);
1013 FILTER_FREE(trace);
1014 FILTER_FREE(error);
1015 FILTER_FREE(trap);
1016 FILTER_FREE(kill);
1017 }
1018
1019 TEST_F(precedence, allow_ok)
1020 {
1021 pid_t parent, res = 0;
1022 long ret;
1023
1024 parent = getppid();
1025 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1026 ASSERT_EQ(0, ret);
1027
1028 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1029 ASSERT_EQ(0, ret);
1030 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1031 ASSERT_EQ(0, ret);
1032 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1033 ASSERT_EQ(0, ret);
1034 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1035 ASSERT_EQ(0, ret);
1036 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1037 ASSERT_EQ(0, ret);
1038 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1039 ASSERT_EQ(0, ret);
1040 /* Should work just fine. */
1041 res = syscall(__NR_getppid);
1042 EXPECT_EQ(parent, res);
1043 }
1044
1045 TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
1046 {
1047 pid_t parent, res = 0;
1048 long ret;
1049
1050 parent = getppid();
1051 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1052 ASSERT_EQ(0, ret);
1053
1054 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1055 ASSERT_EQ(0, ret);
1056 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1057 ASSERT_EQ(0, ret);
1058 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1059 ASSERT_EQ(0, ret);
1060 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1061 ASSERT_EQ(0, ret);
1062 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1063 ASSERT_EQ(0, ret);
1064 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1065 ASSERT_EQ(0, ret);
1066 /* Should work just fine. */
1067 res = syscall(__NR_getppid);
1068 EXPECT_EQ(parent, res);
1069 /* getpid() should never return. */
1070 res = syscall(__NR_getpid);
1071 EXPECT_EQ(0, res);
1072 }
1073
1074 TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
1075 {
1076 pid_t parent;
1077 long ret;
1078
1079 parent = getppid();
1080 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1081 ASSERT_EQ(0, ret);
1082
1083 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1084 ASSERT_EQ(0, ret);
1085 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1086 ASSERT_EQ(0, ret);
1087 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1088 ASSERT_EQ(0, ret);
1089 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1090 ASSERT_EQ(0, ret);
1091 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1092 ASSERT_EQ(0, ret);
1093 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1094 ASSERT_EQ(0, ret);
1095 /* Should work just fine. */
1096 EXPECT_EQ(parent, syscall(__NR_getppid));
1097 /* getpid() should never return. */
1098 EXPECT_EQ(0, syscall(__NR_getpid));
1099 }
1100
1101 TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
1102 {
1103 pid_t parent;
1104 long ret;
1105
1106 parent = getppid();
1107 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1108 ASSERT_EQ(0, ret);
1109
1110 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1111 ASSERT_EQ(0, ret);
1112 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1113 ASSERT_EQ(0, ret);
1114 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1115 ASSERT_EQ(0, ret);
1116 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1117 ASSERT_EQ(0, ret);
1118 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1119 ASSERT_EQ(0, ret);
1120 /* Should work just fine. */
1121 EXPECT_EQ(parent, syscall(__NR_getppid));
1122 /* getpid() should never return. */
1123 EXPECT_EQ(0, syscall(__NR_getpid));
1124 }
1125
1126 TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
1127 {
1128 pid_t parent;
1129 long ret;
1130
1131 parent = getppid();
1132 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1133 ASSERT_EQ(0, ret);
1134
1135 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1136 ASSERT_EQ(0, ret);
1137 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1138 ASSERT_EQ(0, ret);
1139 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1140 ASSERT_EQ(0, ret);
1141 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1142 ASSERT_EQ(0, ret);
1143 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1144 ASSERT_EQ(0, ret);
1145 /* Should work just fine. */
1146 EXPECT_EQ(parent, syscall(__NR_getppid));
1147 /* getpid() should never return. */
1148 EXPECT_EQ(0, syscall(__NR_getpid));
1149 }
1150
1151 TEST_F(precedence, errno_is_third)
1152 {
1153 pid_t parent;
1154 long ret;
1155
1156 parent = getppid();
1157 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1158 ASSERT_EQ(0, ret);
1159
1160 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1161 ASSERT_EQ(0, ret);
1162 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1163 ASSERT_EQ(0, ret);
1164 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1165 ASSERT_EQ(0, ret);
1166 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1167 ASSERT_EQ(0, ret);
1168 /* Should work just fine. */
1169 EXPECT_EQ(parent, syscall(__NR_getppid));
1170 EXPECT_EQ(0, syscall(__NR_getpid));
1171 }
1172
1173 TEST_F(precedence, errno_is_third_in_any_order)
1174 {
1175 pid_t parent;
1176 long ret;
1177
1178 parent = getppid();
1179 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1180 ASSERT_EQ(0, ret);
1181
1182 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1183 ASSERT_EQ(0, ret);
1184 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1185 ASSERT_EQ(0, ret);
1186 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1187 ASSERT_EQ(0, ret);
1188 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1189 ASSERT_EQ(0, ret);
1190 /* Should work just fine. */
1191 EXPECT_EQ(parent, syscall(__NR_getppid));
1192 EXPECT_EQ(0, syscall(__NR_getpid));
1193 }
1194
1195 TEST_F(precedence, trace_is_fourth)
1196 {
1197 pid_t parent;
1198 long ret;
1199
1200 parent = getppid();
1201 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1202 ASSERT_EQ(0, ret);
1203
1204 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1205 ASSERT_EQ(0, ret);
1206 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1207 ASSERT_EQ(0, ret);
1208 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1209 ASSERT_EQ(0, ret);
1210 /* Should work just fine. */
1211 EXPECT_EQ(parent, syscall(__NR_getppid));
1212 /* No ptracer */
1213 EXPECT_EQ(-1, syscall(__NR_getpid));
1214 }
1215
1216 TEST_F(precedence, trace_is_fourth_in_any_order)
1217 {
1218 pid_t parent;
1219 long ret;
1220
1221 parent = getppid();
1222 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1223 ASSERT_EQ(0, ret);
1224
1225 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1226 ASSERT_EQ(0, ret);
1227 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1228 ASSERT_EQ(0, ret);
1229 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1230 ASSERT_EQ(0, ret);
1231 /* Should work just fine. */
1232 EXPECT_EQ(parent, syscall(__NR_getppid));
1233 /* No ptracer */
1234 EXPECT_EQ(-1, syscall(__NR_getpid));
1235 }
1236
1237 TEST_F(precedence, log_is_fifth)
1238 {
1239 pid_t mypid, parent;
1240 long ret;
1241
1242 mypid = getpid();
1243 parent = getppid();
1244 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1245 ASSERT_EQ(0, ret);
1246
1247 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1248 ASSERT_EQ(0, ret);
1249 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1250 ASSERT_EQ(0, ret);
1251 /* Should work just fine. */
1252 EXPECT_EQ(parent, syscall(__NR_getppid));
1253 /* Should also work just fine */
1254 EXPECT_EQ(mypid, syscall(__NR_getpid));
1255 }
1256
1257 TEST_F(precedence, log_is_fifth_in_any_order)
1258 {
1259 pid_t mypid, parent;
1260 long ret;
1261
1262 mypid = getpid();
1263 parent = getppid();
1264 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1265 ASSERT_EQ(0, ret);
1266
1267 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1268 ASSERT_EQ(0, ret);
1269 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1270 ASSERT_EQ(0, ret);
1271 /* Should work just fine. */
1272 EXPECT_EQ(parent, syscall(__NR_getppid));
1273 /* Should also work just fine */
1274 EXPECT_EQ(mypid, syscall(__NR_getpid));
1275 }
1276
1277 #ifndef PTRACE_O_TRACESECCOMP
1278 #define PTRACE_O_TRACESECCOMP 0x00000080
1279 #endif
1280
1281 /* Catch the Ubuntu 12.04 value error. */
1282 #if PTRACE_EVENT_SECCOMP != 7
1283 #undef PTRACE_EVENT_SECCOMP
1284 #endif
1285
1286 #ifndef PTRACE_EVENT_SECCOMP
1287 #define PTRACE_EVENT_SECCOMP 7
1288 #endif
1289
1290 #define IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP)
1291 bool tracer_running;
1292 void tracer_stop(int sig)
1293 {
1294 tracer_running = false;
1295 }
1296
1297 typedef void tracer_func_t(struct __test_metadata *_metadata,
1298 pid_t tracee, int status, void *args);
1299
1300 void start_tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
1301 tracer_func_t tracer_func, void *args, bool ptrace_syscall)
1302 {
1303 int ret = -1;
1304 struct sigaction action = {
1305 .sa_handler = tracer_stop,
1306 };
1307
1308 /* Allow external shutdown. */
1309 tracer_running = true;
1310 ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));
1311
1312 errno = 0;
1313 while (ret == -1 && errno != EINVAL)
1314 ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
1315 ASSERT_EQ(0, ret) {
1316 kill(tracee, SIGKILL);
1317 }
1318 /* Wait for attach stop */
1319 wait(NULL);
1320
1321 ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, ptrace_syscall ?
1322 PTRACE_O_TRACESYSGOOD :
1323 PTRACE_O_TRACESECCOMP);
1324 ASSERT_EQ(0, ret) {
1325 TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
1326 kill(tracee, SIGKILL);
1327 }
1328 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1329 tracee, NULL, 0);
1330 ASSERT_EQ(0, ret);
1331
1332 /* Unblock the tracee */
1333 ASSERT_EQ(1, write(fd, "A", 1));
1334 ASSERT_EQ(0, close(fd));
1335
1336 /* Run until we're shut down. Must assert to stop execution. */
1337 while (tracer_running) {
1338 int status;
1339
1340 if (wait(&status) != tracee)
1341 continue;
1342 if (WIFSIGNALED(status) || WIFEXITED(status))
1343 /* Child is dead. Time to go. */
1344 return;
1345
1346 /* Check if this is a seccomp event. */
1347 ASSERT_EQ(!ptrace_syscall, IS_SECCOMP_EVENT(status));
1348
1349 tracer_func(_metadata, tracee, status, args);
1350
1351 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1352 tracee, NULL, 0);
1353 ASSERT_EQ(0, ret);
1354 }
1355 /* Directly report the status of our test harness results. */
1356 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
1357 }
1358
1359 /* Common tracer setup/teardown functions. */
1360 void cont_handler(int num)
1361 { }
1362 pid_t setup_trace_fixture(struct __test_metadata *_metadata,
1363 tracer_func_t func, void *args, bool ptrace_syscall)
1364 {
1365 char sync;
1366 int pipefd[2];
1367 pid_t tracer_pid;
1368 pid_t tracee = getpid();
1369
1370 /* Setup a pipe for clean synchronization. */
1371 ASSERT_EQ(0, pipe(pipefd));
1372
1373 /* Fork a child which we'll promote to tracer */
1374 tracer_pid = fork();
1375 ASSERT_LE(0, tracer_pid);
1376 signal(SIGALRM, cont_handler);
1377 if (tracer_pid == 0) {
1378 close(pipefd[0]);
1379 start_tracer(_metadata, pipefd[1], tracee, func, args,
1380 ptrace_syscall);
1381 syscall(__NR_exit, 0);
1382 }
1383 close(pipefd[1]);
1384 prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
1385 read(pipefd[0], &sync, 1);
1386 close(pipefd[0]);
1387
1388 return tracer_pid;
1389 }
1390 void teardown_trace_fixture(struct __test_metadata *_metadata,
1391 pid_t tracer)
1392 {
1393 if (tracer) {
1394 int status;
1395 /*
1396 * Extract the exit code from the other process and
1397 * adopt it for ourselves in case its asserts failed.
1398 */
1399 ASSERT_EQ(0, kill(tracer, SIGUSR1));
1400 ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
1401 if (WEXITSTATUS(status))
1402 _metadata->passed = 0;
1403 }
1404 }
1405
1406 /* "poke" tracer arguments and function. */
1407 struct tracer_args_poke_t {
1408 unsigned long poke_addr;
1409 };
1410
1411 void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
1412 void *args)
1413 {
1414 int ret;
1415 unsigned long msg;
1416 struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;
1417
1418 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1419 EXPECT_EQ(0, ret);
1420 /* If this fails, don't try to recover. */
1421 ASSERT_EQ(0x1001, msg) {
1422 kill(tracee, SIGKILL);
1423 }
1424 /*
1425 * Poke in the message.
1426 * Registers are not touched to try to keep this relatively arch
1427 * agnostic.
1428 */
1429 ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
1430 EXPECT_EQ(0, ret);
1431 }
1432
1433 FIXTURE_DATA(TRACE_poke) {
1434 struct sock_fprog prog;
1435 pid_t tracer;
1436 long poked;
1437 struct tracer_args_poke_t tracer_args;
1438 };
1439
1440 FIXTURE_SETUP(TRACE_poke)
1441 {
1442 struct sock_filter filter[] = {
1443 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1444 offsetof(struct seccomp_data, nr)),
1445 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1446 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001),
1447 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1448 };
1449
1450 self->poked = 0;
1451 memset(&self->prog, 0, sizeof(self->prog));
1452 self->prog.filter = malloc(sizeof(filter));
1453 ASSERT_NE(NULL, self->prog.filter);
1454 memcpy(self->prog.filter, filter, sizeof(filter));
1455 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1456
1457 /* Set up tracer args. */
1458 self->tracer_args.poke_addr = (unsigned long)&self->poked;
1459
1460 /* Launch tracer. */
1461 self->tracer = setup_trace_fixture(_metadata, tracer_poke,
1462 &self->tracer_args, false);
1463 }
1464
1465 FIXTURE_TEARDOWN(TRACE_poke)
1466 {
1467 teardown_trace_fixture(_metadata, self->tracer);
1468 if (self->prog.filter)
1469 free(self->prog.filter);
1470 }
1471
1472 TEST_F(TRACE_poke, read_has_side_effects)
1473 {
1474 ssize_t ret;
1475
1476 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1477 ASSERT_EQ(0, ret);
1478
1479 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1480 ASSERT_EQ(0, ret);
1481
1482 EXPECT_EQ(0, self->poked);
1483 ret = read(-1, NULL, 0);
1484 EXPECT_EQ(-1, ret);
1485 EXPECT_EQ(0x1001, self->poked);
1486 }
1487
1488 TEST_F(TRACE_poke, getpid_runs_normally)
1489 {
1490 long ret;
1491
1492 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1493 ASSERT_EQ(0, ret);
1494
1495 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1496 ASSERT_EQ(0, ret);
1497
1498 EXPECT_EQ(0, self->poked);
1499 EXPECT_NE(0, syscall(__NR_getpid));
1500 EXPECT_EQ(0, self->poked);
1501 }
1502
1503 #if defined(__x86_64__)
1504 # define ARCH_REGS struct user_regs_struct
1505 # define SYSCALL_NUM orig_rax
1506 # define SYSCALL_RET rax
1507 #elif defined(__i386__)
1508 # define ARCH_REGS struct user_regs_struct
1509 # define SYSCALL_NUM orig_eax
1510 # define SYSCALL_RET eax
1511 #elif defined(__arm__)
1512 # define ARCH_REGS struct pt_regs
1513 # define SYSCALL_NUM ARM_r7
1514 # define SYSCALL_RET ARM_r0
1515 #elif defined(__aarch64__)
1516 # define ARCH_REGS struct user_pt_regs
1517 # define SYSCALL_NUM regs[8]
1518 # define SYSCALL_RET regs[0]
1519 #elif defined(__hppa__)
1520 # define ARCH_REGS struct user_regs_struct
1521 # define SYSCALL_NUM gr[20]
1522 # define SYSCALL_RET gr[28]
1523 #elif defined(__powerpc__)
1524 # define ARCH_REGS struct pt_regs
1525 # define SYSCALL_NUM gpr[0]
1526 # define SYSCALL_RET gpr[3]
1527 #elif defined(__s390__)
1528 # define ARCH_REGS s390_regs
1529 # define SYSCALL_NUM gprs[2]
1530 # define SYSCALL_RET gprs[2]
1531 #elif defined(__mips__)
1532 # define ARCH_REGS struct pt_regs
1533 # define SYSCALL_NUM regs[2]
1534 # define SYSCALL_SYSCALL_NUM regs[4]
1535 # define SYSCALL_RET regs[2]
1536 # define SYSCALL_NUM_RET_SHARE_REG
1537 #else
1538 # error "Do not know how to find your architecture's registers and syscalls"
1539 #endif
1540
1541 /* When the syscall return can't be changed, stub out the tests for it. */
1542 #ifdef SYSCALL_NUM_RET_SHARE_REG
1543 # define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(-1, action)
1544 #else
1545 # define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(val, action)
1546 #endif
1547
1548 /* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1549 * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1550 */
1551 #if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
1552 #define HAVE_GETREGS
1553 #endif
1554
1555 /* Architecture-specific syscall fetching routine. */
1556 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1557 {
1558 ARCH_REGS regs;
1559 #ifdef HAVE_GETREGS
1560 EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
1561 TH_LOG("PTRACE_GETREGS failed");
1562 return -1;
1563 }
1564 #else
1565 struct iovec iov;
1566
1567 iov.iov_base = &regs;
1568 iov.iov_len = sizeof(regs);
1569 EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1570 TH_LOG("PTRACE_GETREGSET failed");
1571 return -1;
1572 }
1573 #endif
1574
1575 #if defined(__mips__)
1576 if (regs.SYSCALL_NUM == __NR_O32_Linux)
1577 return regs.SYSCALL_SYSCALL_NUM;
1578 #endif
1579 return regs.SYSCALL_NUM;
1580 }
1581
1582 /* Architecture-specific syscall changing routine. */
1583 void change_syscall(struct __test_metadata *_metadata,
1584 pid_t tracee, int syscall)
1585 {
1586 int ret;
1587 ARCH_REGS regs;
1588 #ifdef HAVE_GETREGS
1589 ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
1590 #else
1591 struct iovec iov;
1592 iov.iov_base = &regs;
1593 iov.iov_len = sizeof(regs);
1594 ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
1595 #endif
1596 EXPECT_EQ(0, ret) {}
1597
1598 #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
1599 defined(__s390__) || defined(__hppa__)
1600 {
1601 regs.SYSCALL_NUM = syscall;
1602 }
1603 #elif defined(__mips__)
1604 {
1605 if (regs.SYSCALL_NUM == __NR_O32_Linux)
1606 regs.SYSCALL_SYSCALL_NUM = syscall;
1607 else
1608 regs.SYSCALL_NUM = syscall;
1609 }
1610
1611 #elif defined(__arm__)
1612 # ifndef PTRACE_SET_SYSCALL
1613 # define PTRACE_SET_SYSCALL 23
1614 # endif
1615 {
1616 ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
1617 EXPECT_EQ(0, ret);
1618 }
1619
1620 #elif defined(__aarch64__)
1621 # ifndef NT_ARM_SYSTEM_CALL
1622 # define NT_ARM_SYSTEM_CALL 0x404
1623 # endif
1624 {
1625 iov.iov_base = &syscall;
1626 iov.iov_len = sizeof(syscall);
1627 ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
1628 &iov);
1629 EXPECT_EQ(0, ret);
1630 }
1631
1632 #else
1633 ASSERT_EQ(1, 0) {
1634 TH_LOG("How is the syscall changed on this architecture?");
1635 }
1636 #endif
1637
1638 /* If syscall is skipped, change return value. */
1639 if (syscall == -1)
1640 #ifdef SYSCALL_NUM_RET_SHARE_REG
1641 TH_LOG("Can't modify syscall return on this architecture");
1642 #else
1643 regs.SYSCALL_RET = EPERM;
1644 #endif
1645
1646 #ifdef HAVE_GETREGS
1647 ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
1648 #else
1649 iov.iov_base = &regs;
1650 iov.iov_len = sizeof(regs);
1651 ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
1652 #endif
1653 EXPECT_EQ(0, ret);
1654 }
1655
1656 void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
1657 int status, void *args)
1658 {
1659 int ret;
1660 unsigned long msg;
1661
1662 /* Make sure we got the right message. */
1663 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1664 EXPECT_EQ(0, ret);
1665
1666 /* Validate and take action on expected syscalls. */
1667 switch (msg) {
1668 case 0x1002:
1669 /* change getpid to getppid. */
1670 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
1671 change_syscall(_metadata, tracee, __NR_getppid);
1672 break;
1673 case 0x1003:
1674 /* skip gettid. */
1675 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
1676 change_syscall(_metadata, tracee, -1);
1677 break;
1678 case 0x1004:
1679 /* do nothing (allow getppid) */
1680 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
1681 break;
1682 default:
1683 EXPECT_EQ(0, msg) {
1684 TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1685 kill(tracee, SIGKILL);
1686 }
1687 }
1688
1689 }
1690
1691 void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
1692 int status, void *args)
1693 {
1694 int ret, nr;
1695 unsigned long msg;
1696 static bool entry;
1697
1698 /* Make sure we got an empty message. */
1699 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1700 EXPECT_EQ(0, ret);
1701 EXPECT_EQ(0, msg);
1702
1703 /* The only way to tell PTRACE_SYSCALL entry/exit is by counting. */
1704 entry = !entry;
1705 if (!entry)
1706 return;
1707
1708 nr = get_syscall(_metadata, tracee);
1709
1710 if (nr == __NR_getpid)
1711 change_syscall(_metadata, tracee, __NR_getppid);
1712 if (nr == __NR_open)
1713 change_syscall(_metadata, tracee, -1);
1714 }
1715
1716 FIXTURE_DATA(TRACE_syscall) {
1717 struct sock_fprog prog;
1718 pid_t tracer, mytid, mypid, parent;
1719 };
1720
1721 FIXTURE_SETUP(TRACE_syscall)
1722 {
1723 struct sock_filter filter[] = {
1724 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1725 offsetof(struct seccomp_data, nr)),
1726 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1727 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1728 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1729 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
1730 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1731 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
1732 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1733 };
1734
1735 memset(&self->prog, 0, sizeof(self->prog));
1736 self->prog.filter = malloc(sizeof(filter));
1737 ASSERT_NE(NULL, self->prog.filter);
1738 memcpy(self->prog.filter, filter, sizeof(filter));
1739 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1740
1741 /* Prepare some testable syscall results. */
1742 self->mytid = syscall(__NR_gettid);
1743 ASSERT_GT(self->mytid, 0);
1744 ASSERT_NE(self->mytid, 1) {
1745 TH_LOG("Running this test as init is not supported. :)");
1746 }
1747
1748 self->mypid = getpid();
1749 ASSERT_GT(self->mypid, 0);
1750 ASSERT_EQ(self->mytid, self->mypid);
1751
1752 self->parent = getppid();
1753 ASSERT_GT(self->parent, 0);
1754 ASSERT_NE(self->parent, self->mypid);
1755
1756 /* Launch tracer. */
1757 self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL,
1758 false);
1759 }
1760
1761 FIXTURE_TEARDOWN(TRACE_syscall)
1762 {
1763 teardown_trace_fixture(_metadata, self->tracer);
1764 if (self->prog.filter)
1765 free(self->prog.filter);
1766 }
1767
1768 TEST_F(TRACE_syscall, ptrace_syscall_redirected)
1769 {
1770 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1771 teardown_trace_fixture(_metadata, self->tracer);
1772 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1773 true);
1774
1775 /* Tracer will redirect getpid to getppid. */
1776 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1777 }
1778
1779 TEST_F(TRACE_syscall, ptrace_syscall_dropped)
1780 {
1781 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1782 teardown_trace_fixture(_metadata, self->tracer);
1783 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1784 true);
1785
1786 /* Tracer should skip the open syscall, resulting in EPERM. */
1787 EXPECT_SYSCALL_RETURN(EPERM, syscall(__NR_open));
1788 }
1789
1790 TEST_F(TRACE_syscall, syscall_allowed)
1791 {
1792 long ret;
1793
1794 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1795 ASSERT_EQ(0, ret);
1796
1797 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1798 ASSERT_EQ(0, ret);
1799
1800 /* getppid works as expected (no changes). */
1801 EXPECT_EQ(self->parent, syscall(__NR_getppid));
1802 EXPECT_NE(self->mypid, syscall(__NR_getppid));
1803 }
1804
1805 TEST_F(TRACE_syscall, syscall_redirected)
1806 {
1807 long ret;
1808
1809 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1810 ASSERT_EQ(0, ret);
1811
1812 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1813 ASSERT_EQ(0, ret);
1814
1815 /* getpid has been redirected to getppid as expected. */
1816 EXPECT_EQ(self->parent, syscall(__NR_getpid));
1817 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1818 }
1819
1820 TEST_F(TRACE_syscall, syscall_dropped)
1821 {
1822 long ret;
1823
1824 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1825 ASSERT_EQ(0, ret);
1826
1827 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1828 ASSERT_EQ(0, ret);
1829
1830 /* gettid has been skipped and an altered return value stored. */
1831 EXPECT_SYSCALL_RETURN(EPERM, syscall(__NR_gettid));
1832 EXPECT_NE(self->mytid, syscall(__NR_gettid));
1833 }
1834
1835 TEST_F(TRACE_syscall, skip_after_RET_TRACE)
1836 {
1837 struct sock_filter filter[] = {
1838 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1839 offsetof(struct seccomp_data, nr)),
1840 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1841 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1842 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1843 };
1844 struct sock_fprog prog = {
1845 .len = (unsigned short)ARRAY_SIZE(filter),
1846 .filter = filter,
1847 };
1848 long ret;
1849
1850 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1851 ASSERT_EQ(0, ret);
1852
1853 /* Install fixture filter. */
1854 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1855 ASSERT_EQ(0, ret);
1856
1857 /* Install "errno on getppid" filter. */
1858 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1859 ASSERT_EQ(0, ret);
1860
1861 /* Tracer will redirect getpid to getppid, and we should see EPERM. */
1862 errno = 0;
1863 EXPECT_EQ(-1, syscall(__NR_getpid));
1864 EXPECT_EQ(EPERM, errno);
1865 }
1866
1867 TEST_F_SIGNAL(TRACE_syscall, kill_after_RET_TRACE, SIGSYS)
1868 {
1869 struct sock_filter filter[] = {
1870 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1871 offsetof(struct seccomp_data, nr)),
1872 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1873 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1874 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1875 };
1876 struct sock_fprog prog = {
1877 .len = (unsigned short)ARRAY_SIZE(filter),
1878 .filter = filter,
1879 };
1880 long ret;
1881
1882 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1883 ASSERT_EQ(0, ret);
1884
1885 /* Install fixture filter. */
1886 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1887 ASSERT_EQ(0, ret);
1888
1889 /* Install "death on getppid" filter. */
1890 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1891 ASSERT_EQ(0, ret);
1892
1893 /* Tracer will redirect getpid to getppid, and we should die. */
1894 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1895 }
1896
1897 TEST_F(TRACE_syscall, skip_after_ptrace)
1898 {
1899 struct sock_filter filter[] = {
1900 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1901 offsetof(struct seccomp_data, nr)),
1902 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1903 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1904 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1905 };
1906 struct sock_fprog prog = {
1907 .len = (unsigned short)ARRAY_SIZE(filter),
1908 .filter = filter,
1909 };
1910 long ret;
1911
1912 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1913 teardown_trace_fixture(_metadata, self->tracer);
1914 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1915 true);
1916
1917 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1918 ASSERT_EQ(0, ret);
1919
1920 /* Install "errno on getppid" filter. */
1921 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1922 ASSERT_EQ(0, ret);
1923
1924 /* Tracer will redirect getpid to getppid, and we should see EPERM. */
1925 EXPECT_EQ(-1, syscall(__NR_getpid));
1926 EXPECT_EQ(EPERM, errno);
1927 }
1928
1929 TEST_F_SIGNAL(TRACE_syscall, kill_after_ptrace, SIGSYS)
1930 {
1931 struct sock_filter filter[] = {
1932 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1933 offsetof(struct seccomp_data, nr)),
1934 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1935 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1936 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1937 };
1938 struct sock_fprog prog = {
1939 .len = (unsigned short)ARRAY_SIZE(filter),
1940 .filter = filter,
1941 };
1942 long ret;
1943
1944 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1945 teardown_trace_fixture(_metadata, self->tracer);
1946 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1947 true);
1948
1949 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1950 ASSERT_EQ(0, ret);
1951
1952 /* Install "death on getppid" filter. */
1953 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1954 ASSERT_EQ(0, ret);
1955
1956 /* Tracer will redirect getpid to getppid, and we should die. */
1957 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1958 }
1959
1960 TEST(seccomp_syscall)
1961 {
1962 struct sock_filter filter[] = {
1963 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1964 };
1965 struct sock_fprog prog = {
1966 .len = (unsigned short)ARRAY_SIZE(filter),
1967 .filter = filter,
1968 };
1969 long ret;
1970
1971 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1972 ASSERT_EQ(0, ret) {
1973 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1974 }
1975
1976 /* Reject insane operation. */
1977 ret = seccomp(-1, 0, &prog);
1978 ASSERT_NE(ENOSYS, errno) {
1979 TH_LOG("Kernel does not support seccomp syscall!");
1980 }
1981 EXPECT_EQ(EINVAL, errno) {
1982 TH_LOG("Did not reject crazy op value!");
1983 }
1984
1985 /* Reject strict with flags or pointer. */
1986 ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
1987 EXPECT_EQ(EINVAL, errno) {
1988 TH_LOG("Did not reject mode strict with flags!");
1989 }
1990 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
1991 EXPECT_EQ(EINVAL, errno) {
1992 TH_LOG("Did not reject mode strict with uargs!");
1993 }
1994
1995 /* Reject insane args for filter. */
1996 ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
1997 EXPECT_EQ(EINVAL, errno) {
1998 TH_LOG("Did not reject crazy filter flags!");
1999 }
2000 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
2001 EXPECT_EQ(EFAULT, errno) {
2002 TH_LOG("Did not reject NULL filter!");
2003 }
2004
2005 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2006 EXPECT_EQ(0, errno) {
2007 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
2008 strerror(errno));
2009 }
2010 }
2011
2012 TEST(seccomp_syscall_mode_lock)
2013 {
2014 struct sock_filter filter[] = {
2015 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2016 };
2017 struct sock_fprog prog = {
2018 .len = (unsigned short)ARRAY_SIZE(filter),
2019 .filter = filter,
2020 };
2021 long ret;
2022
2023 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2024 ASSERT_EQ(0, ret) {
2025 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2026 }
2027
2028 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2029 ASSERT_NE(ENOSYS, errno) {
2030 TH_LOG("Kernel does not support seccomp syscall!");
2031 }
2032 EXPECT_EQ(0, ret) {
2033 TH_LOG("Could not install filter!");
2034 }
2035
2036 /* Make sure neither entry point will switch to strict. */
2037 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
2038 EXPECT_EQ(EINVAL, errno) {
2039 TH_LOG("Switched to mode strict!");
2040 }
2041
2042 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
2043 EXPECT_EQ(EINVAL, errno) {
2044 TH_LOG("Switched to mode strict!");
2045 }
2046 }
2047
2048 /*
2049 * Test detection of known and unknown filter flags. Userspace needs to be able
2050 * to check if a filter flag is supported by the current kernel and a good way
2051 * of doing that is by attempting to enter filter mode, with the flag bit in
2052 * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
2053 * that the flag is valid and EINVAL indicates that the flag is invalid.
2054 */
2055 TEST(detect_seccomp_filter_flags)
2056 {
2057 unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
2058 SECCOMP_FILTER_FLAG_LOG };
2059 unsigned int flag, all_flags;
2060 int i;
2061 long ret;
2062
2063 /* Test detection of known-good filter flags */
2064 for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
2065 flag = flags[i];
2066 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2067 ASSERT_NE(ENOSYS, errno) {
2068 TH_LOG("Kernel does not support seccomp syscall!");
2069 }
2070 EXPECT_EQ(-1, ret);
2071 EXPECT_EQ(EFAULT, errno) {
2072 TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
2073 flag);
2074 }
2075
2076 all_flags |= flag;
2077 }
2078
2079 /* Test detection of all known-good filter flags */
2080 ret = seccomp(SECCOMP_SET_MODE_FILTER, all_flags, NULL);
2081 EXPECT_EQ(-1, ret);
2082 EXPECT_EQ(EFAULT, errno) {
2083 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
2084 all_flags);
2085 }
2086
2087 /* Test detection of an unknown filter flag */
2088 flag = -1;
2089 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2090 EXPECT_EQ(-1, ret);
2091 EXPECT_EQ(EINVAL, errno) {
2092 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
2093 flag);
2094 }
2095
2096 /*
2097 * Test detection of an unknown filter flag that may simply need to be
2098 * added to this test
2099 */
2100 flag = flags[ARRAY_SIZE(flags) - 1] << 1;
2101 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2102 EXPECT_EQ(-1, ret);
2103 EXPECT_EQ(EINVAL, errno) {
2104 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?",
2105 flag);
2106 }
2107 }
2108
2109 TEST(TSYNC_first)
2110 {
2111 struct sock_filter filter[] = {
2112 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2113 };
2114 struct sock_fprog prog = {
2115 .len = (unsigned short)ARRAY_SIZE(filter),
2116 .filter = filter,
2117 };
2118 long ret;
2119
2120 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2121 ASSERT_EQ(0, ret) {
2122 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2123 }
2124
2125 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2126 &prog);
2127 ASSERT_NE(ENOSYS, errno) {
2128 TH_LOG("Kernel does not support seccomp syscall!");
2129 }
2130 EXPECT_EQ(0, ret) {
2131 TH_LOG("Could not install initial filter with TSYNC!");
2132 }
2133 }
2134
2135 #define TSYNC_SIBLINGS 2
2136 struct tsync_sibling {
2137 pthread_t tid;
2138 pid_t system_tid;
2139 sem_t *started;
2140 pthread_cond_t *cond;
2141 pthread_mutex_t *mutex;
2142 int diverge;
2143 int num_waits;
2144 struct sock_fprog *prog;
2145 struct __test_metadata *metadata;
2146 };
2147
2148 /*
2149 * To avoid joining joined threads (which is not allowed by Bionic),
2150 * make sure we both successfully join and clear the tid to skip a
2151 * later join attempt during fixture teardown. Any remaining threads
2152 * will be directly killed during teardown.
2153 */
2154 #define PTHREAD_JOIN(tid, status) \
2155 do { \
2156 int _rc = pthread_join(tid, status); \
2157 if (_rc) { \
2158 TH_LOG("pthread_join of tid %u failed: %d\n", \
2159 (unsigned int)tid, _rc); \
2160 } else { \
2161 tid = 0; \
2162 } \
2163 } while (0)
2164
2165 FIXTURE_DATA(TSYNC) {
2166 struct sock_fprog root_prog, apply_prog;
2167 struct tsync_sibling sibling[TSYNC_SIBLINGS];
2168 sem_t started;
2169 pthread_cond_t cond;
2170 pthread_mutex_t mutex;
2171 int sibling_count;
2172 };
2173
2174 FIXTURE_SETUP(TSYNC)
2175 {
2176 struct sock_filter root_filter[] = {
2177 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2178 };
2179 struct sock_filter apply_filter[] = {
2180 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2181 offsetof(struct seccomp_data, nr)),
2182 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
2183 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2184 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2185 };
2186
2187 memset(&self->root_prog, 0, sizeof(self->root_prog));
2188 memset(&self->apply_prog, 0, sizeof(self->apply_prog));
2189 memset(&self->sibling, 0, sizeof(self->sibling));
2190 self->root_prog.filter = malloc(sizeof(root_filter));
2191 ASSERT_NE(NULL, self->root_prog.filter);
2192 memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
2193 self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
2194
2195 self->apply_prog.filter = malloc(sizeof(apply_filter));
2196 ASSERT_NE(NULL, self->apply_prog.filter);
2197 memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
2198 self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
2199
2200 self->sibling_count = 0;
2201 pthread_mutex_init(&self->mutex, NULL);
2202 pthread_cond_init(&self->cond, NULL);
2203 sem_init(&self->started, 0, 0);
2204 self->sibling[0].tid = 0;
2205 self->sibling[0].cond = &self->cond;
2206 self->sibling[0].started = &self->started;
2207 self->sibling[0].mutex = &self->mutex;
2208 self->sibling[0].diverge = 0;
2209 self->sibling[0].num_waits = 1;
2210 self->sibling[0].prog = &self->root_prog;
2211 self->sibling[0].metadata = _metadata;
2212 self->sibling[1].tid = 0;
2213 self->sibling[1].cond = &self->cond;
2214 self->sibling[1].started = &self->started;
2215 self->sibling[1].mutex = &self->mutex;
2216 self->sibling[1].diverge = 0;
2217 self->sibling[1].prog = &self->root_prog;
2218 self->sibling[1].num_waits = 1;
2219 self->sibling[1].metadata = _metadata;
2220 }
2221
2222 FIXTURE_TEARDOWN(TSYNC)
2223 {
2224 int sib = 0;
2225
2226 if (self->root_prog.filter)
2227 free(self->root_prog.filter);
2228 if (self->apply_prog.filter)
2229 free(self->apply_prog.filter);
2230
2231 for ( ; sib < self->sibling_count; ++sib) {
2232 struct tsync_sibling *s = &self->sibling[sib];
2233
2234 if (!s->tid)
2235 continue;
2236 /*
2237 * If a thread is still running, it may be stuck, so hit
2238 * it over the head really hard.
2239 */
2240 pthread_kill(s->tid, 9);
2241 }
2242 pthread_mutex_destroy(&self->mutex);
2243 pthread_cond_destroy(&self->cond);
2244 sem_destroy(&self->started);
2245 }
2246
2247 void *tsync_sibling(void *data)
2248 {
2249 long ret = 0;
2250 struct tsync_sibling *me = data;
2251
2252 me->system_tid = syscall(__NR_gettid);
2253
2254 pthread_mutex_lock(me->mutex);
2255 if (me->diverge) {
2256 /* Just re-apply the root prog to fork the tree */
2257 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
2258 me->prog, 0, 0);
2259 }
2260 sem_post(me->started);
2261 /* Return outside of started so parent notices failures. */
2262 if (ret) {
2263 pthread_mutex_unlock(me->mutex);
2264 return (void *)SIBLING_EXIT_FAILURE;
2265 }
2266 do {
2267 pthread_cond_wait(me->cond, me->mutex);
2268 me->num_waits = me->num_waits - 1;
2269 } while (me->num_waits);
2270 pthread_mutex_unlock(me->mutex);
2271
2272 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
2273 if (!ret)
2274 return (void *)SIBLING_EXIT_NEWPRIVS;
2275 read(0, NULL, 0);
2276 return (void *)SIBLING_EXIT_UNKILLED;
2277 }
2278
2279 void tsync_start_sibling(struct tsync_sibling *sibling)
2280 {
2281 pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
2282 }
2283
2284 TEST_F(TSYNC, siblings_fail_prctl)
2285 {
2286 long ret;
2287 void *status;
2288 struct sock_filter filter[] = {
2289 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2290 offsetof(struct seccomp_data, nr)),
2291 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
2292 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
2293 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2294 };
2295 struct sock_fprog prog = {
2296 .len = (unsigned short)ARRAY_SIZE(filter),
2297 .filter = filter,
2298 };
2299
2300 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2301 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2302 }
2303
2304 /* Check prctl failure detection by requesting sib 0 diverge. */
2305 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2306 ASSERT_NE(ENOSYS, errno) {
2307 TH_LOG("Kernel does not support seccomp syscall!");
2308 }
2309 ASSERT_EQ(0, ret) {
2310 TH_LOG("setting filter failed");
2311 }
2312
2313 self->sibling[0].diverge = 1;
2314 tsync_start_sibling(&self->sibling[0]);
2315 tsync_start_sibling(&self->sibling[1]);
2316
2317 while (self->sibling_count < TSYNC_SIBLINGS) {
2318 sem_wait(&self->started);
2319 self->sibling_count++;
2320 }
2321
2322 /* Signal the threads to clean up*/
2323 pthread_mutex_lock(&self->mutex);
2324 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2325 TH_LOG("cond broadcast non-zero");
2326 }
2327 pthread_mutex_unlock(&self->mutex);
2328
2329 /* Ensure diverging sibling failed to call prctl. */
2330 PTHREAD_JOIN(self->sibling[0].tid, &status);
2331 EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
2332 PTHREAD_JOIN(self->sibling[1].tid, &status);
2333 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2334 }
2335
2336 TEST_F(TSYNC, two_siblings_with_ancestor)
2337 {
2338 long ret;
2339 void *status;
2340
2341 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2342 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2343 }
2344
2345 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2346 ASSERT_NE(ENOSYS, errno) {
2347 TH_LOG("Kernel does not support seccomp syscall!");
2348 }
2349 ASSERT_EQ(0, ret) {
2350 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2351 }
2352 tsync_start_sibling(&self->sibling[0]);
2353 tsync_start_sibling(&self->sibling[1]);
2354
2355 while (self->sibling_count < TSYNC_SIBLINGS) {
2356 sem_wait(&self->started);
2357 self->sibling_count++;
2358 }
2359
2360 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2361 &self->apply_prog);
2362 ASSERT_EQ(0, ret) {
2363 TH_LOG("Could install filter on all threads!");
2364 }
2365 /* Tell the siblings to test the policy */
2366 pthread_mutex_lock(&self->mutex);
2367 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2368 TH_LOG("cond broadcast non-zero");
2369 }
2370 pthread_mutex_unlock(&self->mutex);
2371 /* Ensure they are both killed and don't exit cleanly. */
2372 PTHREAD_JOIN(self->sibling[0].tid, &status);
2373 EXPECT_EQ(0x0, (long)status);
2374 PTHREAD_JOIN(self->sibling[1].tid, &status);
2375 EXPECT_EQ(0x0, (long)status);
2376 }
2377
2378 TEST_F(TSYNC, two_sibling_want_nnp)
2379 {
2380 void *status;
2381
2382 /* start siblings before any prctl() operations */
2383 tsync_start_sibling(&self->sibling[0]);
2384 tsync_start_sibling(&self->sibling[1]);
2385 while (self->sibling_count < TSYNC_SIBLINGS) {
2386 sem_wait(&self->started);
2387 self->sibling_count++;
2388 }
2389
2390 /* Tell the siblings to test no policy */
2391 pthread_mutex_lock(&self->mutex);
2392 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2393 TH_LOG("cond broadcast non-zero");
2394 }
2395 pthread_mutex_unlock(&self->mutex);
2396
2397 /* Ensure they are both upset about lacking nnp. */
2398 PTHREAD_JOIN(self->sibling[0].tid, &status);
2399 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2400 PTHREAD_JOIN(self->sibling[1].tid, &status);
2401 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2402 }
2403
2404 TEST_F(TSYNC, two_siblings_with_no_filter)
2405 {
2406 long ret;
2407 void *status;
2408
2409 /* start siblings before any prctl() operations */
2410 tsync_start_sibling(&self->sibling[0]);
2411 tsync_start_sibling(&self->sibling[1]);
2412 while (self->sibling_count < TSYNC_SIBLINGS) {
2413 sem_wait(&self->started);
2414 self->sibling_count++;
2415 }
2416
2417 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2418 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2419 }
2420
2421 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2422 &self->apply_prog);
2423 ASSERT_NE(ENOSYS, errno) {
2424 TH_LOG("Kernel does not support seccomp syscall!");
2425 }
2426 ASSERT_EQ(0, ret) {
2427 TH_LOG("Could install filter on all threads!");
2428 }
2429
2430 /* Tell the siblings to test the policy */
2431 pthread_mutex_lock(&self->mutex);
2432 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2433 TH_LOG("cond broadcast non-zero");
2434 }
2435 pthread_mutex_unlock(&self->mutex);
2436
2437 /* Ensure they are both killed and don't exit cleanly. */
2438 PTHREAD_JOIN(self->sibling[0].tid, &status);
2439 EXPECT_EQ(0x0, (long)status);
2440 PTHREAD_JOIN(self->sibling[1].tid, &status);
2441 EXPECT_EQ(0x0, (long)status);
2442 }
2443
2444 TEST_F(TSYNC, two_siblings_with_one_divergence)
2445 {
2446 long ret;
2447 void *status;
2448
2449 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2450 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2451 }
2452
2453 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2454 ASSERT_NE(ENOSYS, errno) {
2455 TH_LOG("Kernel does not support seccomp syscall!");
2456 }
2457 ASSERT_EQ(0, ret) {
2458 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2459 }
2460 self->sibling[0].diverge = 1;
2461 tsync_start_sibling(&self->sibling[0]);
2462 tsync_start_sibling(&self->sibling[1]);
2463
2464 while (self->sibling_count < TSYNC_SIBLINGS) {
2465 sem_wait(&self->started);
2466 self->sibling_count++;
2467 }
2468
2469 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2470 &self->apply_prog);
2471 ASSERT_EQ(self->sibling[0].system_tid, ret) {
2472 TH_LOG("Did not fail on diverged sibling.");
2473 }
2474
2475 /* Wake the threads */
2476 pthread_mutex_lock(&self->mutex);
2477 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2478 TH_LOG("cond broadcast non-zero");
2479 }
2480 pthread_mutex_unlock(&self->mutex);
2481
2482 /* Ensure they are both unkilled. */
2483 PTHREAD_JOIN(self->sibling[0].tid, &status);
2484 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2485 PTHREAD_JOIN(self->sibling[1].tid, &status);
2486 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2487 }
2488
2489 TEST_F(TSYNC, two_siblings_not_under_filter)
2490 {
2491 long ret, sib;
2492 void *status;
2493
2494 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2495 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2496 }
2497
2498 /*
2499 * Sibling 0 will have its own seccomp policy
2500 * and Sibling 1 will not be under seccomp at
2501 * all. Sibling 1 will enter seccomp and 0
2502 * will cause failure.
2503 */
2504 self->sibling[0].diverge = 1;
2505 tsync_start_sibling(&self->sibling[0]);
2506 tsync_start_sibling(&self->sibling[1]);
2507
2508 while (self->sibling_count < TSYNC_SIBLINGS) {
2509 sem_wait(&self->started);
2510 self->sibling_count++;
2511 }
2512
2513 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2514 ASSERT_NE(ENOSYS, errno) {
2515 TH_LOG("Kernel does not support seccomp syscall!");
2516 }
2517 ASSERT_EQ(0, ret) {
2518 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2519 }
2520
2521 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2522 &self->apply_prog);
2523 ASSERT_EQ(ret, self->sibling[0].system_tid) {
2524 TH_LOG("Did not fail on diverged sibling.");
2525 }
2526 sib = 1;
2527 if (ret == self->sibling[0].system_tid)
2528 sib = 0;
2529
2530 pthread_mutex_lock(&self->mutex);
2531
2532 /* Increment the other siblings num_waits so we can clean up
2533 * the one we just saw.
2534 */
2535 self->sibling[!sib].num_waits += 1;
2536
2537 /* Signal the thread to clean up*/
2538 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2539 TH_LOG("cond broadcast non-zero");
2540 }
2541 pthread_mutex_unlock(&self->mutex);
2542 PTHREAD_JOIN(self->sibling[sib].tid, &status);
2543 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2544 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2545 while (!kill(self->sibling[sib].system_tid, 0))
2546 sleep(0.1);
2547 /* Switch to the remaining sibling */
2548 sib = !sib;
2549
2550 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2551 &self->apply_prog);
2552 ASSERT_EQ(0, ret) {
2553 TH_LOG("Expected the remaining sibling to sync");
2554 };
2555
2556 pthread_mutex_lock(&self->mutex);
2557
2558 /* If remaining sibling didn't have a chance to wake up during
2559 * the first broadcast, manually reduce the num_waits now.
2560 */
2561 if (self->sibling[sib].num_waits > 1)
2562 self->sibling[sib].num_waits = 1;
2563 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2564 TH_LOG("cond broadcast non-zero");
2565 }
2566 pthread_mutex_unlock(&self->mutex);
2567 PTHREAD_JOIN(self->sibling[sib].tid, &status);
2568 EXPECT_EQ(0, (long)status);
2569 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2570 while (!kill(self->sibling[sib].system_tid, 0))
2571 sleep(0.1);
2572
2573 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2574 &self->apply_prog);
2575 ASSERT_EQ(0, ret); /* just us chickens */
2576 }
2577
2578 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
2579 TEST(syscall_restart)
2580 {
2581 long ret;
2582 unsigned long msg;
2583 pid_t child_pid;
2584 int pipefd[2];
2585 int status;
2586 siginfo_t info = { };
2587 struct sock_filter filter[] = {
2588 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2589 offsetof(struct seccomp_data, nr)),
2590
2591 #ifdef __NR_sigreturn
2592 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0),
2593 #endif
2594 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
2595 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
2596 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
2597 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0),
2598 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2599
2600 /* Allow __NR_write for easy logging. */
2601 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2602 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2603 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2604 /* The nanosleep jump target. */
2605 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2606 /* The restart_syscall jump target. */
2607 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
2608 };
2609 struct sock_fprog prog = {
2610 .len = (unsigned short)ARRAY_SIZE(filter),
2611 .filter = filter,
2612 };
2613 #if defined(__arm__)
2614 struct utsname utsbuf;
2615 #endif
2616
2617 ASSERT_EQ(0, pipe(pipefd));
2618
2619 child_pid = fork();
2620 ASSERT_LE(0, child_pid);
2621 if (child_pid == 0) {
2622 /* Child uses EXPECT not ASSERT to deliver status correctly. */
2623 char buf = ' ';
2624 struct timespec timeout = { };
2625
2626 /* Attach parent as tracer and stop. */
2627 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2628 EXPECT_EQ(0, raise(SIGSTOP));
2629
2630 EXPECT_EQ(0, close(pipefd[1]));
2631
2632 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2633 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2634 }
2635
2636 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2637 EXPECT_EQ(0, ret) {
2638 TH_LOG("Failed to install filter!");
2639 }
2640
2641 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2642 TH_LOG("Failed to read() sync from parent");
2643 }
2644 EXPECT_EQ('.', buf) {
2645 TH_LOG("Failed to get sync data from read()");
2646 }
2647
2648 /* Start nanosleep to be interrupted. */
2649 timeout.tv_sec = 1;
2650 errno = 0;
2651 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2652 TH_LOG("Call to nanosleep() failed (errno %d)", errno);
2653 }
2654
2655 /* Read final sync from parent. */
2656 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2657 TH_LOG("Failed final read() from parent");
2658 }
2659 EXPECT_EQ('!', buf) {
2660 TH_LOG("Failed to get final data from read()");
2661 }
2662
2663 /* Directly report the status of our test harness results. */
2664 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2665 : EXIT_FAILURE);
2666 }
2667 EXPECT_EQ(0, close(pipefd[0]));
2668
2669 /* Attach to child, setup options, and release. */
2670 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2671 ASSERT_EQ(true, WIFSTOPPED(status));
2672 ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2673 PTRACE_O_TRACESECCOMP));
2674 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2675 ASSERT_EQ(1, write(pipefd[1], ".", 1));
2676
2677 /* Wait for nanosleep() to start. */
2678 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2679 ASSERT_EQ(true, WIFSTOPPED(status));
2680 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2681 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2682 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2683 ASSERT_EQ(0x100, msg);
2684 EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
2685
2686 /* Might as well check siginfo for sanity while we're here. */
2687 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2688 ASSERT_EQ(SIGTRAP, info.si_signo);
2689 ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2690 EXPECT_EQ(0, info.si_errno);
2691 EXPECT_EQ(getuid(), info.si_uid);
2692 /* Verify signal delivery came from child (seccomp-triggered). */
2693 EXPECT_EQ(child_pid, info.si_pid);
2694
2695 /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
2696 ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2697 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2698 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2699 ASSERT_EQ(true, WIFSTOPPED(status));
2700 ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
2701 /* Verify signal delivery came from parent now. */
2702 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2703 EXPECT_EQ(getpid(), info.si_pid);
2704
2705 /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
2706 ASSERT_EQ(0, kill(child_pid, SIGCONT));
2707 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2708 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2709 ASSERT_EQ(true, WIFSTOPPED(status));
2710 ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2711 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2712
2713 /* Wait for restart_syscall() to start. */
2714 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2715 ASSERT_EQ(true, WIFSTOPPED(status));
2716 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2717 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2718 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2719
2720 ASSERT_EQ(0x200, msg);
2721 ret = get_syscall(_metadata, child_pid);
2722 #if defined(__arm__)
2723 /*
2724 * FIXME:
2725 * - native ARM registers do NOT expose true syscall.
2726 * - compat ARM registers on ARM64 DO expose true syscall.
2727 */
2728 ASSERT_EQ(0, uname(&utsbuf));
2729 if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2730 EXPECT_EQ(__NR_nanosleep, ret);
2731 } else
2732 #endif
2733 {
2734 EXPECT_EQ(__NR_restart_syscall, ret);
2735 }
2736
2737 /* Write again to end test. */
2738 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2739 ASSERT_EQ(1, write(pipefd[1], "!", 1));
2740 EXPECT_EQ(0, close(pipefd[1]));
2741
2742 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2743 if (WIFSIGNALED(status) || WEXITSTATUS(status))
2744 _metadata->passed = 0;
2745 }
2746
2747 TEST_SIGNAL(filter_flag_log, SIGSYS)
2748 {
2749 struct sock_filter allow_filter[] = {
2750 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2751 };
2752 struct sock_filter kill_filter[] = {
2753 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2754 offsetof(struct seccomp_data, nr)),
2755 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
2756 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2757 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2758 };
2759 struct sock_fprog allow_prog = {
2760 .len = (unsigned short)ARRAY_SIZE(allow_filter),
2761 .filter = allow_filter,
2762 };
2763 struct sock_fprog kill_prog = {
2764 .len = (unsigned short)ARRAY_SIZE(kill_filter),
2765 .filter = kill_filter,
2766 };
2767 long ret;
2768 pid_t parent = getppid();
2769
2770 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2771 ASSERT_EQ(0, ret);
2772
2773 /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
2774 ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
2775 &allow_prog);
2776 ASSERT_NE(ENOSYS, errno) {
2777 TH_LOG("Kernel does not support seccomp syscall!");
2778 }
2779 EXPECT_NE(0, ret) {
2780 TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
2781 }
2782 EXPECT_EQ(EINVAL, errno) {
2783 TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
2784 }
2785
2786 /* Verify that a simple, permissive filter can be added with no flags */
2787 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
2788 EXPECT_EQ(0, ret);
2789
2790 /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
2791 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2792 &allow_prog);
2793 ASSERT_NE(EINVAL, errno) {
2794 TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
2795 }
2796 EXPECT_EQ(0, ret);
2797
2798 /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
2799 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2800 &kill_prog);
2801 EXPECT_EQ(0, ret);
2802
2803 EXPECT_EQ(parent, syscall(__NR_getppid));
2804 /* getpid() should never return. */
2805 EXPECT_EQ(0, syscall(__NR_getpid));
2806 }
2807
2808 TEST(get_action_avail)
2809 {
2810 __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
2811 SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
2812 SECCOMP_RET_LOG, SECCOMP_RET_ALLOW };
2813 __u32 unknown_action = 0x10000000U;
2814 int i;
2815 long ret;
2816
2817 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
2818 ASSERT_NE(ENOSYS, errno) {
2819 TH_LOG("Kernel does not support seccomp syscall!");
2820 }
2821 ASSERT_NE(EINVAL, errno) {
2822 TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
2823 }
2824 EXPECT_EQ(ret, 0);
2825
2826 for (i = 0; i < ARRAY_SIZE(actions); i++) {
2827 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
2828 EXPECT_EQ(ret, 0) {
2829 TH_LOG("Expected action (0x%X) not available!",
2830 actions[i]);
2831 }
2832 }
2833
2834 /* Check that an unknown action is handled properly (EOPNOTSUPP) */
2835 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
2836 EXPECT_EQ(ret, -1);
2837 EXPECT_EQ(errno, EOPNOTSUPP);
2838 }
2839
2840 /*
2841 * TODO:
2842 * - add microbenchmarks
2843 * - expand NNP testing
2844 * - better arch-specific TRACE and TRAP handlers.
2845 * - endianness checking when appropriate
2846 * - 64-bit arg prodding
2847 * - arch value testing (x86 modes especially)
2848 * - verify that FILTER_FLAG_LOG filters generate log messages
2849 * - verify that RET_LOG generates log messages
2850 * - ...
2851 */
2852
2853 TEST_HARNESS_MAIN
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