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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 /* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1250  * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1251  */
1252 #if defined(__x86_64__) || defined(__i386__)
1253 #define HAVE_GETREGS
1254 #endif
1255 
1256 /* Architecture-specific syscall fetching routine. */
get_syscall(struct __test_metadata * _metadata,pid_t tracee)1257 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1258 {
1259 	ARCH_REGS regs;
1260 #ifdef HAVE_GETREGS
1261 	EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
1262 		TH_LOG("PTRACE_GETREGS failed");
1263 		return -1;
1264 	}
1265 #else
1266 	struct iovec iov;
1267 
1268 	iov.iov_base = &regs;
1269 	iov.iov_len = sizeof(regs);
1270 	EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1271 		TH_LOG("PTRACE_GETREGSET failed");
1272 		return -1;
1273 	}
1274 #endif
1275 
1276 	return regs.SYSCALL_NUM;
1277 }
1278 
1279 /* Architecture-specific syscall changing routine. */
change_syscall(struct __test_metadata * _metadata,pid_t tracee,int syscall)1280 void change_syscall(struct __test_metadata *_metadata,
1281 		    pid_t tracee, int syscall)
1282 {
1283 	int ret;
1284 	ARCH_REGS regs;
1285 #ifdef HAVE_GETREGS
1286 	ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
1287 #else
1288 	struct iovec iov;
1289 	iov.iov_base = &regs;
1290 	iov.iov_len = sizeof(regs);
1291 	ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
1292 #endif
1293 	EXPECT_EQ(0, ret);
1294 
1295 #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
1296     defined(__s390__)
1297 	{
1298 		regs.SYSCALL_NUM = syscall;
1299 	}
1300 
1301 #elif defined(__arm__)
1302 # ifndef PTRACE_SET_SYSCALL
1303 #  define PTRACE_SET_SYSCALL   23
1304 # endif
1305 	{
1306 		ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
1307 		EXPECT_EQ(0, ret);
1308 	}
1309 
1310 #elif defined(__aarch64__)
1311 # ifndef NT_ARM_SYSTEM_CALL
1312 #  define NT_ARM_SYSTEM_CALL 0x404
1313 # endif
1314 	{
1315 		iov.iov_base = &syscall;
1316 		iov.iov_len = sizeof(syscall);
1317 		ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
1318 			     &iov);
1319 		EXPECT_EQ(0, ret);
1320 	}
1321 
1322 #else
1323 	ASSERT_EQ(1, 0) {
1324 		TH_LOG("How is the syscall changed on this architecture?");
1325 	}
1326 #endif
1327 
1328 	/* If syscall is skipped, change return value. */
1329 	if (syscall == -1)
1330 		regs.SYSCALL_RET = 1;
1331 
1332 #ifdef HAVE_GETREGS
1333 	ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
1334 #else
1335 	iov.iov_base = &regs;
1336 	iov.iov_len = sizeof(regs);
1337 	ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
1338 #endif
1339 	EXPECT_EQ(0, ret);
1340 }
1341 
tracer_syscall(struct __test_metadata * _metadata,pid_t tracee,int status,void * args)1342 void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
1343 		    int status, void *args)
1344 {
1345 	int ret;
1346 	unsigned long msg;
1347 
1348 	/* Make sure we got the right message. */
1349 	ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1350 	EXPECT_EQ(0, ret);
1351 
1352 	/* Validate and take action on expected syscalls. */
1353 	switch (msg) {
1354 	case 0x1002:
1355 		/* change getpid to getppid. */
1356 		EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
1357 		change_syscall(_metadata, tracee, __NR_getppid);
1358 		break;
1359 	case 0x1003:
1360 		/* skip gettid. */
1361 		EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
1362 		change_syscall(_metadata, tracee, -1);
1363 		break;
1364 	case 0x1004:
1365 		/* do nothing (allow getppid) */
1366 		EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
1367 		break;
1368 	default:
1369 		EXPECT_EQ(0, msg) {
1370 			TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1371 			kill(tracee, SIGKILL);
1372 		}
1373 	}
1374 
1375 }
1376 
FIXTURE_DATA(TRACE_syscall)1377 FIXTURE_DATA(TRACE_syscall) {
1378 	struct sock_fprog prog;
1379 	pid_t tracer, mytid, mypid, parent;
1380 };
1381 
FIXTURE_SETUP(TRACE_syscall)1382 FIXTURE_SETUP(TRACE_syscall)
1383 {
1384 	struct sock_filter filter[] = {
1385 		BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1386 			offsetof(struct seccomp_data, nr)),
1387 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1388 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1389 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1390 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
1391 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1392 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
1393 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1394 	};
1395 
1396 	memset(&self->prog, 0, sizeof(self->prog));
1397 	self->prog.filter = malloc(sizeof(filter));
1398 	ASSERT_NE(NULL, self->prog.filter);
1399 	memcpy(self->prog.filter, filter, sizeof(filter));
1400 	self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1401 
1402 	/* Prepare some testable syscall results. */
1403 	self->mytid = syscall(__NR_gettid);
1404 	ASSERT_GT(self->mytid, 0);
1405 	ASSERT_NE(self->mytid, 1) {
1406 		TH_LOG("Running this test as init is not supported. :)");
1407 	}
1408 
1409 	self->mypid = getpid();
1410 	ASSERT_GT(self->mypid, 0);
1411 	ASSERT_EQ(self->mytid, self->mypid);
1412 
1413 	self->parent = getppid();
1414 	ASSERT_GT(self->parent, 0);
1415 	ASSERT_NE(self->parent, self->mypid);
1416 
1417 	/* Launch tracer. */
1418 	self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL);
1419 }
1420 
FIXTURE_TEARDOWN(TRACE_syscall)1421 FIXTURE_TEARDOWN(TRACE_syscall)
1422 {
1423 	teardown_trace_fixture(_metadata, self->tracer);
1424 	if (self->prog.filter)
1425 		free(self->prog.filter);
1426 }
1427 
TEST_F(TRACE_syscall,syscall_allowed)1428 TEST_F(TRACE_syscall, syscall_allowed)
1429 {
1430 	long ret;
1431 
1432 	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1433 	ASSERT_EQ(0, ret);
1434 
1435 	ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1436 	ASSERT_EQ(0, ret);
1437 
1438 	/* getppid works as expected (no changes). */
1439 	EXPECT_EQ(self->parent, syscall(__NR_getppid));
1440 	EXPECT_NE(self->mypid, syscall(__NR_getppid));
1441 }
1442 
TEST_F(TRACE_syscall,syscall_redirected)1443 TEST_F(TRACE_syscall, syscall_redirected)
1444 {
1445 	long ret;
1446 
1447 	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1448 	ASSERT_EQ(0, ret);
1449 
1450 	ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1451 	ASSERT_EQ(0, ret);
1452 
1453 	/* getpid has been redirected to getppid as expected. */
1454 	EXPECT_EQ(self->parent, syscall(__NR_getpid));
1455 	EXPECT_NE(self->mypid, syscall(__NR_getpid));
1456 }
1457 
TEST_F(TRACE_syscall,syscall_dropped)1458 TEST_F(TRACE_syscall, syscall_dropped)
1459 {
1460 	long ret;
1461 
1462 	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1463 	ASSERT_EQ(0, ret);
1464 
1465 	ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1466 	ASSERT_EQ(0, ret);
1467 
1468 	/* gettid has been skipped and an altered return value stored. */
1469 	EXPECT_EQ(1, syscall(__NR_gettid));
1470 	EXPECT_NE(self->mytid, syscall(__NR_gettid));
1471 }
1472 
1473 #ifndef __NR_seccomp
1474 # if defined(__i386__)
1475 #  define __NR_seccomp 354
1476 # elif defined(__x86_64__)
1477 #  define __NR_seccomp 317
1478 # elif defined(__arm__)
1479 #  define __NR_seccomp 383
1480 # elif defined(__aarch64__)
1481 #  define __NR_seccomp 277
1482 # elif defined(__powerpc__)
1483 #  define __NR_seccomp 358
1484 # elif defined(__s390__)
1485 #  define __NR_seccomp 348
1486 # else
1487 #  warning "seccomp syscall number unknown for this architecture"
1488 #  define __NR_seccomp 0xffff
1489 # endif
1490 #endif
1491 
1492 #ifndef SECCOMP_SET_MODE_STRICT
1493 #define SECCOMP_SET_MODE_STRICT 0
1494 #endif
1495 
1496 #ifndef SECCOMP_SET_MODE_FILTER
1497 #define SECCOMP_SET_MODE_FILTER 1
1498 #endif
1499 
1500 #ifndef SECCOMP_FLAG_FILTER_TSYNC
1501 #define SECCOMP_FLAG_FILTER_TSYNC 1
1502 #endif
1503 
1504 #ifndef seccomp
seccomp(unsigned int op,unsigned int flags,struct sock_fprog * filter)1505 int seccomp(unsigned int op, unsigned int flags, struct sock_fprog *filter)
1506 {
1507 	errno = 0;
1508 	return syscall(__NR_seccomp, op, flags, filter);
1509 }
1510 #endif
1511 
TEST(seccomp_syscall)1512 TEST(seccomp_syscall)
1513 {
1514 	struct sock_filter filter[] = {
1515 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1516 	};
1517 	struct sock_fprog prog = {
1518 		.len = (unsigned short)ARRAY_SIZE(filter),
1519 		.filter = filter,
1520 	};
1521 	long ret;
1522 
1523 	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1524 	ASSERT_EQ(0, ret) {
1525 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1526 	}
1527 
1528 	/* Reject insane operation. */
1529 	ret = seccomp(-1, 0, &prog);
1530 	ASSERT_NE(ENOSYS, errno) {
1531 		TH_LOG("Kernel does not support seccomp syscall!");
1532 	}
1533 	EXPECT_EQ(EINVAL, errno) {
1534 		TH_LOG("Did not reject crazy op value!");
1535 	}
1536 
1537 	/* Reject strict with flags or pointer. */
1538 	ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
1539 	EXPECT_EQ(EINVAL, errno) {
1540 		TH_LOG("Did not reject mode strict with flags!");
1541 	}
1542 	ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
1543 	EXPECT_EQ(EINVAL, errno) {
1544 		TH_LOG("Did not reject mode strict with uargs!");
1545 	}
1546 
1547 	/* Reject insane args for filter. */
1548 	ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
1549 	EXPECT_EQ(EINVAL, errno) {
1550 		TH_LOG("Did not reject crazy filter flags!");
1551 	}
1552 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
1553 	EXPECT_EQ(EFAULT, errno) {
1554 		TH_LOG("Did not reject NULL filter!");
1555 	}
1556 
1557 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
1558 	EXPECT_EQ(0, errno) {
1559 		TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
1560 			strerror(errno));
1561 	}
1562 }
1563 
TEST(seccomp_syscall_mode_lock)1564 TEST(seccomp_syscall_mode_lock)
1565 {
1566 	struct sock_filter filter[] = {
1567 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1568 	};
1569 	struct sock_fprog prog = {
1570 		.len = (unsigned short)ARRAY_SIZE(filter),
1571 		.filter = filter,
1572 	};
1573 	long ret;
1574 
1575 	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
1576 	ASSERT_EQ(0, ret) {
1577 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1578 	}
1579 
1580 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
1581 	ASSERT_NE(ENOSYS, errno) {
1582 		TH_LOG("Kernel does not support seccomp syscall!");
1583 	}
1584 	EXPECT_EQ(0, ret) {
1585 		TH_LOG("Could not install filter!");
1586 	}
1587 
1588 	/* Make sure neither entry point will switch to strict. */
1589 	ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
1590 	EXPECT_EQ(EINVAL, errno) {
1591 		TH_LOG("Switched to mode strict!");
1592 	}
1593 
1594 	ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
1595 	EXPECT_EQ(EINVAL, errno) {
1596 		TH_LOG("Switched to mode strict!");
1597 	}
1598 }
1599 
TEST(TSYNC_first)1600 TEST(TSYNC_first)
1601 {
1602 	struct sock_filter filter[] = {
1603 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1604 	};
1605 	struct sock_fprog prog = {
1606 		.len = (unsigned short)ARRAY_SIZE(filter),
1607 		.filter = filter,
1608 	};
1609 	long ret;
1610 
1611 	ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
1612 	ASSERT_EQ(0, ret) {
1613 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1614 	}
1615 
1616 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
1617 		      &prog);
1618 	ASSERT_NE(ENOSYS, errno) {
1619 		TH_LOG("Kernel does not support seccomp syscall!");
1620 	}
1621 	EXPECT_EQ(0, ret) {
1622 		TH_LOG("Could not install initial filter with TSYNC!");
1623 	}
1624 }
1625 
1626 #define TSYNC_SIBLINGS 2
1627 struct tsync_sibling {
1628 	pthread_t tid;
1629 	pid_t system_tid;
1630 	sem_t *started;
1631 	pthread_cond_t *cond;
1632 	pthread_mutex_t *mutex;
1633 	int diverge;
1634 	int num_waits;
1635 	struct sock_fprog *prog;
1636 	struct __test_metadata *metadata;
1637 };
1638 
FIXTURE_DATA(TSYNC)1639 FIXTURE_DATA(TSYNC) {
1640 	struct sock_fprog root_prog, apply_prog;
1641 	struct tsync_sibling sibling[TSYNC_SIBLINGS];
1642 	sem_t started;
1643 	pthread_cond_t cond;
1644 	pthread_mutex_t mutex;
1645 	int sibling_count;
1646 };
1647 
FIXTURE_SETUP(TSYNC)1648 FIXTURE_SETUP(TSYNC)
1649 {
1650 	struct sock_filter root_filter[] = {
1651 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1652 	};
1653 	struct sock_filter apply_filter[] = {
1654 		BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1655 			offsetof(struct seccomp_data, nr)),
1656 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1657 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1658 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1659 	};
1660 
1661 	memset(&self->root_prog, 0, sizeof(self->root_prog));
1662 	memset(&self->apply_prog, 0, sizeof(self->apply_prog));
1663 	memset(&self->sibling, 0, sizeof(self->sibling));
1664 	self->root_prog.filter = malloc(sizeof(root_filter));
1665 	ASSERT_NE(NULL, self->root_prog.filter);
1666 	memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
1667 	self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
1668 
1669 	self->apply_prog.filter = malloc(sizeof(apply_filter));
1670 	ASSERT_NE(NULL, self->apply_prog.filter);
1671 	memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
1672 	self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
1673 
1674 	self->sibling_count = 0;
1675 	pthread_mutex_init(&self->mutex, NULL);
1676 	pthread_cond_init(&self->cond, NULL);
1677 	sem_init(&self->started, 0, 0);
1678 	self->sibling[0].tid = 0;
1679 	self->sibling[0].cond = &self->cond;
1680 	self->sibling[0].started = &self->started;
1681 	self->sibling[0].mutex = &self->mutex;
1682 	self->sibling[0].diverge = 0;
1683 	self->sibling[0].num_waits = 1;
1684 	self->sibling[0].prog = &self->root_prog;
1685 	self->sibling[0].metadata = _metadata;
1686 	self->sibling[1].tid = 0;
1687 	self->sibling[1].cond = &self->cond;
1688 	self->sibling[1].started = &self->started;
1689 	self->sibling[1].mutex = &self->mutex;
1690 	self->sibling[1].diverge = 0;
1691 	self->sibling[1].prog = &self->root_prog;
1692 	self->sibling[1].num_waits = 1;
1693 	self->sibling[1].metadata = _metadata;
1694 }
1695 
FIXTURE_TEARDOWN(TSYNC)1696 FIXTURE_TEARDOWN(TSYNC)
1697 {
1698 	int sib = 0;
1699 
1700 	if (self->root_prog.filter)
1701 		free(self->root_prog.filter);
1702 	if (self->apply_prog.filter)
1703 		free(self->apply_prog.filter);
1704 
1705 	for ( ; sib < self->sibling_count; ++sib) {
1706 		struct tsync_sibling *s = &self->sibling[sib];
1707 		void *status;
1708 
1709 		if (!s->tid)
1710 			continue;
1711 		if (pthread_kill(s->tid, 0)) {
1712 			//pthread_cancel(s->tid);  // ANDROID
1713 			pthread_join(s->tid, &status);
1714 		}
1715 	}
1716 	pthread_mutex_destroy(&self->mutex);
1717 	pthread_cond_destroy(&self->cond);
1718 	sem_destroy(&self->started);
1719 }
1720 
tsync_sibling(void * data)1721 void *tsync_sibling(void *data)
1722 {
1723 	long ret = 0;
1724 	struct tsync_sibling *me = data;
1725 
1726 	me->system_tid = syscall(__NR_gettid);
1727 
1728 	pthread_mutex_lock(me->mutex);
1729 	if (me->diverge) {
1730 		/* Just re-apply the root prog to fork the tree */
1731 		ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
1732 				me->prog, 0, 0);
1733 	}
1734 	sem_post(me->started);
1735 	/* Return outside of started so parent notices failures. */
1736 	if (ret) {
1737 		pthread_mutex_unlock(me->mutex);
1738 		return (void *)SIBLING_EXIT_FAILURE;
1739 	}
1740 	do {
1741 		pthread_cond_wait(me->cond, me->mutex);
1742 		me->num_waits = me->num_waits - 1;
1743 	} while (me->num_waits);
1744 	pthread_mutex_unlock(me->mutex);
1745 
1746 	ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
1747 	if (!ret)
1748 		return (void *)SIBLING_EXIT_NEWPRIVS;
1749 	read(0, NULL, 0);
1750 	return (void *)SIBLING_EXIT_UNKILLED;
1751 }
1752 
tsync_start_sibling(struct tsync_sibling * sibling)1753 void tsync_start_sibling(struct tsync_sibling *sibling)
1754 {
1755 	pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
1756 }
1757 
TEST_F(TSYNC,siblings_fail_prctl)1758 TEST_F(TSYNC, siblings_fail_prctl)
1759 {
1760 	long ret;
1761 	void *status;
1762 	struct sock_filter filter[] = {
1763 		BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1764 			offsetof(struct seccomp_data, nr)),
1765 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
1766 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
1767 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1768 	};
1769 	struct sock_fprog prog = {
1770 		.len = (unsigned short)ARRAY_SIZE(filter),
1771 		.filter = filter,
1772 	};
1773 
1774 	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1775 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1776 	}
1777 
1778 	/* Check prctl failure detection by requesting sib 0 diverge. */
1779 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
1780 	ASSERT_NE(ENOSYS, errno) {
1781 		TH_LOG("Kernel does not support seccomp syscall!");
1782 	}
1783 	ASSERT_EQ(0, ret) {
1784 		TH_LOG("setting filter failed");
1785 	}
1786 
1787 	self->sibling[0].diverge = 1;
1788 	tsync_start_sibling(&self->sibling[0]);
1789 	tsync_start_sibling(&self->sibling[1]);
1790 
1791 	while (self->sibling_count < TSYNC_SIBLINGS) {
1792 		sem_wait(&self->started);
1793 		self->sibling_count++;
1794 	}
1795 
1796 	/* Signal the threads to clean up*/
1797 	pthread_mutex_lock(&self->mutex);
1798 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1799 		TH_LOG("cond broadcast non-zero");
1800 	}
1801 	pthread_mutex_unlock(&self->mutex);
1802 
1803 	/* Ensure diverging sibling failed to call prctl. */
1804 	pthread_join(self->sibling[0].tid, &status);
1805 	EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
1806 	self->sibling[0].tid = 0;
1807 	pthread_join(self->sibling[1].tid, &status);
1808 	EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
1809 	self->sibling[1].tid = 0;
1810 }
1811 
TEST_F(TSYNC,two_siblings_with_ancestor)1812 TEST_F(TSYNC, two_siblings_with_ancestor)
1813 {
1814 	long ret;
1815 	void *status;
1816 
1817 	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1818 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1819 	}
1820 
1821 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
1822 	ASSERT_NE(ENOSYS, errno) {
1823 		TH_LOG("Kernel does not support seccomp syscall!");
1824 	}
1825 	ASSERT_EQ(0, ret) {
1826 		TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
1827 	}
1828 	tsync_start_sibling(&self->sibling[0]);
1829 	tsync_start_sibling(&self->sibling[1]);
1830 
1831 	while (self->sibling_count < TSYNC_SIBLINGS) {
1832 		sem_wait(&self->started);
1833 		self->sibling_count++;
1834 	}
1835 
1836 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
1837 		      &self->apply_prog);
1838 	ASSERT_EQ(0, ret) {
1839 		TH_LOG("Could install filter on all threads!");
1840 	}
1841 	/* Tell the siblings to test the policy */
1842 	pthread_mutex_lock(&self->mutex);
1843 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1844 		TH_LOG("cond broadcast non-zero");
1845 	}
1846 	pthread_mutex_unlock(&self->mutex);
1847 	/* Ensure they are both killed and don't exit cleanly. */
1848 	pthread_join(self->sibling[0].tid, &status);
1849 	EXPECT_EQ(0x0, (long)status);
1850 	self->sibling[0].tid = 0;
1851 	pthread_join(self->sibling[1].tid, &status);
1852 	EXPECT_EQ(0x0, (long)status);
1853 	self->sibling[1].tid = 0;
1854 }
1855 
TEST_F(TSYNC,two_sibling_want_nnp)1856 TEST_F(TSYNC, two_sibling_want_nnp)
1857 {
1858 	void *status;
1859 
1860 	/* start siblings before any prctl() operations */
1861 	tsync_start_sibling(&self->sibling[0]);
1862 	tsync_start_sibling(&self->sibling[1]);
1863 	while (self->sibling_count < TSYNC_SIBLINGS) {
1864 		sem_wait(&self->started);
1865 		self->sibling_count++;
1866 	}
1867 
1868 	/* Tell the siblings to test no policy */
1869 	pthread_mutex_lock(&self->mutex);
1870 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1871 		TH_LOG("cond broadcast non-zero");
1872 	}
1873 	pthread_mutex_unlock(&self->mutex);
1874 
1875 	/* Ensure they are both upset about lacking nnp. */
1876 	pthread_join(self->sibling[0].tid, &status);
1877 	EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
1878 	pthread_join(self->sibling[1].tid, &status);
1879 	EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
1880 }
1881 
TEST_F(TSYNC,two_siblings_with_no_filter)1882 TEST_F(TSYNC, two_siblings_with_no_filter)
1883 {
1884 	long ret;
1885 	void *status;
1886 
1887 	/* start siblings before any prctl() operations */
1888 	tsync_start_sibling(&self->sibling[0]);
1889 	tsync_start_sibling(&self->sibling[1]);
1890 	while (self->sibling_count < TSYNC_SIBLINGS) {
1891 		sem_wait(&self->started);
1892 		self->sibling_count++;
1893 	}
1894 
1895 	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1896 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1897 	}
1898 
1899 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
1900 		      &self->apply_prog);
1901 	ASSERT_NE(ENOSYS, errno) {
1902 		TH_LOG("Kernel does not support seccomp syscall!");
1903 	}
1904 	ASSERT_EQ(0, ret) {
1905 		TH_LOG("Could install filter on all threads!");
1906 	}
1907 
1908 	/* Tell the siblings to test the policy */
1909 	pthread_mutex_lock(&self->mutex);
1910 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1911 		TH_LOG("cond broadcast non-zero");
1912 	}
1913 	pthread_mutex_unlock(&self->mutex);
1914 
1915 	/* Ensure they are both killed and don't exit cleanly. */
1916 	pthread_join(self->sibling[0].tid, &status);
1917 	EXPECT_EQ(0x0, (long)status);
1918 	self->sibling[0].tid = 0;
1919 	pthread_join(self->sibling[1].tid, &status);
1920 	EXPECT_EQ(0x0, (long)status);
1921 	self->sibling[1].tid = 0;
1922 }
1923 
TEST_F(TSYNC,two_siblings_with_one_divergence)1924 TEST_F(TSYNC, two_siblings_with_one_divergence)
1925 {
1926 	long ret;
1927 	void *status;
1928 
1929 	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1930 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1931 	}
1932 
1933 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
1934 	ASSERT_NE(ENOSYS, errno) {
1935 		TH_LOG("Kernel does not support seccomp syscall!");
1936 	}
1937 	ASSERT_EQ(0, ret) {
1938 		TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
1939 	}
1940 	self->sibling[0].diverge = 1;
1941 	tsync_start_sibling(&self->sibling[0]);
1942 	tsync_start_sibling(&self->sibling[1]);
1943 
1944 	while (self->sibling_count < TSYNC_SIBLINGS) {
1945 		sem_wait(&self->started);
1946 		self->sibling_count++;
1947 	}
1948 
1949 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
1950 		      &self->apply_prog);
1951 	ASSERT_EQ(self->sibling[0].system_tid, ret) {
1952 		TH_LOG("Did not fail on diverged sibling.");
1953 	}
1954 
1955 	/* Wake the threads */
1956 	pthread_mutex_lock(&self->mutex);
1957 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
1958 		TH_LOG("cond broadcast non-zero");
1959 	}
1960 	pthread_mutex_unlock(&self->mutex);
1961 
1962 	/* Ensure they are both unkilled. */
1963 	pthread_join(self->sibling[0].tid, &status);
1964 	EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
1965 	self->sibling[0].tid = 0;
1966 	pthread_join(self->sibling[1].tid, &status);
1967 	EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
1968 	self->sibling[1].tid = 0;
1969 }
1970 
TEST_F(TSYNC,two_siblings_not_under_filter)1971 TEST_F(TSYNC, two_siblings_not_under_filter)
1972 {
1973 	long ret, sib;
1974 	void *status;
1975 
1976 	ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
1977 		TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1978 	}
1979 
1980 	/*
1981 	 * Sibling 0 will have its own seccomp policy
1982 	 * and Sibling 1 will not be under seccomp at
1983 	 * all. Sibling 1 will enter seccomp and 0
1984 	 * will cause failure.
1985 	 */
1986 	self->sibling[0].diverge = 1;
1987 	tsync_start_sibling(&self->sibling[0]);
1988 	tsync_start_sibling(&self->sibling[1]);
1989 
1990 	while (self->sibling_count < TSYNC_SIBLINGS) {
1991 		sem_wait(&self->started);
1992 		self->sibling_count++;
1993 	}
1994 
1995 	ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
1996 	ASSERT_NE(ENOSYS, errno) {
1997 		TH_LOG("Kernel does not support seccomp syscall!");
1998 	}
1999 	ASSERT_EQ(0, ret) {
2000 		TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2001 	}
2002 
2003 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
2004 		      &self->apply_prog);
2005 	ASSERT_EQ(ret, self->sibling[0].system_tid) {
2006 		TH_LOG("Did not fail on diverged sibling.");
2007 	}
2008 	sib = 1;
2009 	if (ret == self->sibling[0].system_tid)
2010 		sib = 0;
2011 
2012 	pthread_mutex_lock(&self->mutex);
2013 
2014 	/* Increment the other siblings num_waits so we can clean up
2015 	 * the one we just saw.
2016 	 */
2017 	self->sibling[!sib].num_waits += 1;
2018 
2019 	/* Signal the thread to clean up*/
2020 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2021 		TH_LOG("cond broadcast non-zero");
2022 	}
2023 	pthread_mutex_unlock(&self->mutex);
2024 	pthread_join(self->sibling[sib].tid, &status);
2025 	EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2026 	self->sibling[sib].tid = 0;
2027 	/* Poll for actual task death. pthread_join doesn't guarantee it. */
2028 	while (!kill(self->sibling[sib].system_tid, 0))
2029 		sleep(0.1);
2030 	/* Switch to the remaining sibling */
2031 	sib = !sib;
2032 
2033 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
2034 		      &self->apply_prog);
2035 	ASSERT_EQ(0, ret) {
2036 		TH_LOG("Expected the remaining sibling to sync");
2037 	};
2038 
2039 	pthread_mutex_lock(&self->mutex);
2040 
2041 	/* If remaining sibling didn't have a chance to wake up during
2042 	 * the first broadcast, manually reduce the num_waits now.
2043 	 */
2044 	if (self->sibling[sib].num_waits > 1)
2045 		self->sibling[sib].num_waits = 1;
2046 	ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2047 		TH_LOG("cond broadcast non-zero");
2048 	}
2049 	pthread_mutex_unlock(&self->mutex);
2050 	pthread_join(self->sibling[sib].tid, &status);
2051 	EXPECT_EQ(0, (long)status);
2052 	self->sibling[sib].tid = 0;
2053 	/* Poll for actual task death. pthread_join doesn't guarantee it. */
2054 	while (!kill(self->sibling[sib].system_tid, 0))
2055 		sleep(0.1);
2056 
2057 	ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FLAG_FILTER_TSYNC,
2058 		      &self->apply_prog);
2059 	ASSERT_EQ(0, ret);  /* just us chickens */
2060 }
2061 
2062 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
TEST(syscall_restart)2063 TEST(syscall_restart)
2064 {
2065 	long ret;
2066 	unsigned long msg;
2067 	pid_t child_pid;
2068 	int pipefd[2];
2069 	int status;
2070 	siginfo_t info = { };
2071 	struct sock_filter filter[] = {
2072 		BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2073 			 offsetof(struct seccomp_data, nr)),
2074 
2075 #ifdef __NR_sigreturn
2076 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0),
2077 #endif
2078 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
2079 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
2080 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
2081 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0),
2082 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2083 
2084 		/* Allow __NR_write for easy logging. */
2085 		BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2086 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2087 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2088 		/* The nanosleep jump target. */
2089 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2090 		/* The restart_syscall jump target. */
2091 		BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
2092 	};
2093 	struct sock_fprog prog = {
2094 		.len = (unsigned short)ARRAY_SIZE(filter),
2095 		.filter = filter,
2096 	};
2097 #if defined(__arm__)
2098 	struct utsname utsbuf;
2099 #endif
2100 
2101 	ASSERT_EQ(0, pipe(pipefd));
2102 
2103 	child_pid = fork();
2104 	ASSERT_LE(0, child_pid);
2105 	if (child_pid == 0) {
2106 		/* Child uses EXPECT not ASSERT to deliver status correctly. */
2107 		char buf = ' ';
2108 		struct timespec timeout = { };
2109 
2110 		/* Attach parent as tracer and stop. */
2111 		EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2112 		EXPECT_EQ(0, raise(SIGSTOP));
2113 
2114 		EXPECT_EQ(0, close(pipefd[1]));
2115 
2116 		EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2117 			TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2118 		}
2119 
2120 		ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2121 		EXPECT_EQ(0, ret) {
2122 			TH_LOG("Failed to install filter!");
2123 		}
2124 
2125 		EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2126 			TH_LOG("Failed to read() sync from parent");
2127 		}
2128 		EXPECT_EQ('.', buf) {
2129 			TH_LOG("Failed to get sync data from read()");
2130 		}
2131 
2132 		/* Start nanosleep to be interrupted. */
2133 		timeout.tv_sec = 1;
2134 		errno = 0;
2135 		EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2136 			TH_LOG("Call to nanosleep() failed (errno %d)", errno);
2137 		}
2138 
2139 		/* Read final sync from parent. */
2140 		EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2141 			TH_LOG("Failed final read() from parent");
2142 		}
2143 		EXPECT_EQ('!', buf) {
2144 			TH_LOG("Failed to get final data from read()");
2145 		}
2146 
2147 		/* Directly report the status of our test harness results. */
2148 		syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2149 						     : EXIT_FAILURE);
2150 	}
2151 	EXPECT_EQ(0, close(pipefd[0]));
2152 
2153 	/* Attach to child, setup options, and release. */
2154 	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2155 	ASSERT_EQ(true, WIFSTOPPED(status));
2156 	ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2157 			    PTRACE_O_TRACESECCOMP));
2158 	ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2159 	ASSERT_EQ(1, write(pipefd[1], ".", 1));
2160 
2161 	/* Wait for nanosleep() to start. */
2162 	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2163 	ASSERT_EQ(true, WIFSTOPPED(status));
2164 	ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2165 	ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2166 	ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2167 	ASSERT_EQ(0x100, msg);
2168 	EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
2169 
2170 	/* Might as well check siginfo for sanity while we're here. */
2171 	ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2172 	ASSERT_EQ(SIGTRAP, info.si_signo);
2173 	ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2174 	EXPECT_EQ(0, info.si_errno);
2175 	EXPECT_EQ(getuid(), info.si_uid);
2176 	/* Verify signal delivery came from child (seccomp-triggered). */
2177 	EXPECT_EQ(child_pid, info.si_pid);
2178 
2179 	/* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
2180 	ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2181 	ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2182 	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2183 	ASSERT_EQ(true, WIFSTOPPED(status));
2184 	ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
2185 	/* Verify signal delivery came from parent now. */
2186 	ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2187 	EXPECT_EQ(getpid(), info.si_pid);
2188 
2189 	/* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
2190 	ASSERT_EQ(0, kill(child_pid, SIGCONT));
2191 	ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2192 	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2193 	ASSERT_EQ(true, WIFSTOPPED(status));
2194 	ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2195 	ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2196 
2197 	/* Wait for restart_syscall() to start. */
2198 	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2199 	ASSERT_EQ(true, WIFSTOPPED(status));
2200 	ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2201 	ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2202 	ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2203 
2204 	ASSERT_EQ(0x200, msg);
2205 	ret = get_syscall(_metadata, child_pid);
2206 #if defined(__arm__)
2207 	/*
2208 	 * FIXME:
2209 	 * - native ARM registers do NOT expose true syscall.
2210 	 * - compat ARM registers on ARM64 DO expose true syscall.
2211 	 */
2212 	ASSERT_EQ(0, uname(&utsbuf));
2213 	if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2214 		EXPECT_EQ(__NR_nanosleep, ret);
2215 	} else
2216 #endif
2217 	{
2218 		EXPECT_EQ(__NR_restart_syscall, ret);
2219 	}
2220 
2221 	/* Write again to end test. */
2222 	ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2223 	ASSERT_EQ(1, write(pipefd[1], "!", 1));
2224 	EXPECT_EQ(0, close(pipefd[1]));
2225 
2226 	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2227 	if (WIFSIGNALED(status) || WEXITSTATUS(status))
2228 		_metadata->passed = 0;
2229 }
2230 
2231 /*
2232  * TODO:
2233  * - add microbenchmarks
2234  * - expand NNP testing
2235  * - better arch-specific TRACE and TRAP handlers.
2236  * - endianness checking when appropriate
2237  * - 64-bit arg prodding
2238  * - arch value testing (x86 modes especially)
2239  * - ...
2240  */
2241 
2242 // ANDROID:begin
get_seccomp_test_list()2243 struct __test_metadata* get_seccomp_test_list() {
2244   return __test_list;
2245 }
2246 // ANDROID:end
2247 
2248 TEST_HARNESS_MAIN
2249