blob: 0fad0dc6233865bf5a20293070223ffeaf703c23 [file] [log] [blame]
Kees Cookc99ee512015-06-16 10:54:14 -07001/*
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
Tycho Andersen6a21cc52018-12-09 11:24:13 -07008#define _GNU_SOURCE
Matt Redfearn0ce105b2016-03-29 09:35:29 +01009#include <sys/types.h>
Kees Cook10859f32017-09-07 16:32:46 -070010
11/*
12 * glibc 2.26 and later have SIGSYS in siginfo_t. Before that,
13 * we need to use the kernel's siginfo.h file and trick glibc
14 * into accepting it.
15 */
16#if !__GLIBC_PREREQ(2, 26)
17# include <asm/siginfo.h>
18# define __have_siginfo_t 1
19# define __have_sigval_t 1
20# define __have_sigevent_t 1
21#endif
Kees Cookc99ee512015-06-16 10:54:14 -070022
23#include <errno.h>
24#include <linux/filter.h>
25#include <sys/prctl.h>
26#include <sys/ptrace.h>
27#include <sys/user.h>
28#include <linux/prctl.h>
29#include <linux/ptrace.h>
30#include <linux/seccomp.h>
Kees Cookc99ee512015-06-16 10:54:14 -070031#include <pthread.h>
32#include <semaphore.h>
33#include <signal.h>
34#include <stddef.h>
35#include <stdbool.h>
36#include <string.h>
Kees Cook256d0af2015-10-06 12:30:25 -070037#include <time.h>
Kees Cookc99ee512015-06-16 10:54:14 -070038#include <linux/elf.h>
39#include <sys/uio.h>
Kees Cook256d0af2015-10-06 12:30:25 -070040#include <sys/utsname.h>
Robert Sesekfd88d162015-11-02 15:28:49 -050041#include <sys/fcntl.h>
42#include <sys/mman.h>
43#include <sys/times.h>
Tycho Andersen6a21cc52018-12-09 11:24:13 -070044#include <sys/socket.h>
45#include <sys/ioctl.h>
Kees Cookc99ee512015-06-16 10:54:14 -070046
Kees Cookc99ee512015-06-16 10:54:14 -070047#include <unistd.h>
48#include <sys/syscall.h>
Tycho Andersen6a21cc52018-12-09 11:24:13 -070049#include <poll.h>
Kees Cookc99ee512015-06-16 10:54:14 -070050
Mickaël Salaün0b408082017-05-26 20:43:56 +020051#include "../kselftest_harness.h"
Kees Cookc99ee512015-06-16 10:54:14 -070052
53#ifndef PR_SET_PTRACER
54# define PR_SET_PTRACER 0x59616d61
55#endif
56
57#ifndef PR_SET_NO_NEW_PRIVS
58#define PR_SET_NO_NEW_PRIVS 38
59#define PR_GET_NO_NEW_PRIVS 39
60#endif
61
62#ifndef PR_SECCOMP_EXT
63#define PR_SECCOMP_EXT 43
64#endif
65
66#ifndef SECCOMP_EXT_ACT
67#define SECCOMP_EXT_ACT 1
68#endif
69
70#ifndef SECCOMP_EXT_ACT_TSYNC
71#define SECCOMP_EXT_ACT_TSYNC 1
72#endif
73
74#ifndef SECCOMP_MODE_STRICT
75#define SECCOMP_MODE_STRICT 1
76#endif
77
78#ifndef SECCOMP_MODE_FILTER
79#define SECCOMP_MODE_FILTER 2
80#endif
81
Kees Cookf3e18212017-08-11 13:20:33 -070082#ifndef SECCOMP_RET_ALLOW
Kees Cookc99ee512015-06-16 10:54:14 -070083struct seccomp_data {
84 int nr;
85 __u32 arch;
86 __u64 instruction_pointer;
87 __u64 args[6];
88};
89#endif
90
Kees Cookf3e18212017-08-11 13:20:33 -070091#ifndef SECCOMP_RET_KILL_PROCESS
92#define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process */
Kees Cookfd768752017-08-11 12:53:18 -070093#define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread */
94#endif
Kees Cookc99ee512015-06-16 10:54:14 -070095#ifndef SECCOMP_RET_KILL
Kees Cookfd768752017-08-11 12:53:18 -070096#define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD
97#define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
98#define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
99#define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
100#define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
Tyler Hicks59f5cf42017-08-11 04:33:57 +0000101#endif
102#ifndef SECCOMP_RET_LOG
Kees Cookfd768752017-08-11 12:53:18 -0700103#define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */
Tyler Hicks59f5cf42017-08-11 04:33:57 +0000104#endif
Kees Cookc99ee512015-06-16 10:54:14 -0700105
Kees Cookf3e18212017-08-11 13:20:33 -0700106#ifndef __NR_seccomp
107# if defined(__i386__)
108# define __NR_seccomp 354
109# elif defined(__x86_64__)
110# define __NR_seccomp 317
111# elif defined(__arm__)
112# define __NR_seccomp 383
113# elif defined(__aarch64__)
114# define __NR_seccomp 277
115# elif defined(__hppa__)
116# define __NR_seccomp 338
117# elif defined(__powerpc__)
118# define __NR_seccomp 358
119# elif defined(__s390__)
120# define __NR_seccomp 348
121# else
122# warning "seccomp syscall number unknown for this architecture"
123# define __NR_seccomp 0xffff
124# endif
125#endif
Kees Cookc99ee512015-06-16 10:54:14 -0700126
Kees Cookf3e18212017-08-11 13:20:33 -0700127#ifndef SECCOMP_SET_MODE_STRICT
128#define SECCOMP_SET_MODE_STRICT 0
129#endif
130
131#ifndef SECCOMP_SET_MODE_FILTER
132#define SECCOMP_SET_MODE_FILTER 1
133#endif
134
135#ifndef SECCOMP_GET_ACTION_AVAIL
136#define SECCOMP_GET_ACTION_AVAIL 2
137#endif
138
Tycho Andersen6a21cc52018-12-09 11:24:13 -0700139#ifndef SECCOMP_GET_NOTIF_SIZES
140#define SECCOMP_GET_NOTIF_SIZES 3
141#endif
142
Kees Cookf3e18212017-08-11 13:20:33 -0700143#ifndef SECCOMP_FILTER_FLAG_TSYNC
Kees Cook00a02d02018-05-03 14:56:12 -0700144#define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
Kees Cookf3e18212017-08-11 13:20:33 -0700145#endif
146
147#ifndef SECCOMP_FILTER_FLAG_LOG
Kees Cook00a02d02018-05-03 14:56:12 -0700148#define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
149#endif
150
151#ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
152#define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
Kees Cookf3e18212017-08-11 13:20:33 -0700153#endif
154
Tycho Andersend057dc42018-02-20 19:47:47 -0700155#ifndef PTRACE_SECCOMP_GET_METADATA
156#define PTRACE_SECCOMP_GET_METADATA 0x420d
157
158struct seccomp_metadata {
159 __u64 filter_off; /* Input: which filter */
160 __u64 flags; /* Output: filter's flags */
161};
162#endif
163
Tycho Andersen6a21cc52018-12-09 11:24:13 -0700164#ifndef SECCOMP_FILTER_FLAG_NEW_LISTENER
165#define SECCOMP_FILTER_FLAG_NEW_LISTENER (1UL << 3)
166
167#define SECCOMP_RET_USER_NOTIF 0x7fc00000U
168
169#define SECCOMP_IOC_MAGIC '!'
170#define SECCOMP_IO(nr) _IO(SECCOMP_IOC_MAGIC, nr)
171#define SECCOMP_IOR(nr, type) _IOR(SECCOMP_IOC_MAGIC, nr, type)
172#define SECCOMP_IOW(nr, type) _IOW(SECCOMP_IOC_MAGIC, nr, type)
173#define SECCOMP_IOWR(nr, type) _IOWR(SECCOMP_IOC_MAGIC, nr, type)
174
175/* Flags for seccomp notification fd ioctl. */
176#define SECCOMP_IOCTL_NOTIF_RECV SECCOMP_IOWR(0, struct seccomp_notif)
177#define SECCOMP_IOCTL_NOTIF_SEND SECCOMP_IOWR(1, \
178 struct seccomp_notif_resp)
179#define SECCOMP_IOCTL_NOTIF_ID_VALID SECCOMP_IOR(2, __u64)
180
181struct seccomp_notif {
182 __u64 id;
183 __u32 pid;
184 __u32 flags;
185 struct seccomp_data data;
186};
187
188struct seccomp_notif_resp {
189 __u64 id;
190 __s64 val;
191 __s32 error;
192 __u32 flags;
193};
194
195struct seccomp_notif_sizes {
196 __u16 seccomp_notif;
197 __u16 seccomp_notif_resp;
198 __u16 seccomp_data;
199};
200#endif
201
Kees Cookf3e18212017-08-11 13:20:33 -0700202#ifndef seccomp
203int seccomp(unsigned int op, unsigned int flags, void *args)
204{
205 errno = 0;
206 return syscall(__NR_seccomp, op, flags, args);
207}
Kees Cookc99ee512015-06-16 10:54:14 -0700208#endif
209
Michael Ellermanc385d0d2015-07-23 20:21:10 +1000210#if __BYTE_ORDER == __LITTLE_ENDIAN
Kees Cookc99ee512015-06-16 10:54:14 -0700211#define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
Michael Ellermanc385d0d2015-07-23 20:21:10 +1000212#elif __BYTE_ORDER == __BIG_ENDIAN
213#define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
214#else
215#error "wut? Unknown __BYTE_ORDER?!"
216#endif
Kees Cookc99ee512015-06-16 10:54:14 -0700217
218#define SIBLING_EXIT_UNKILLED 0xbadbeef
219#define SIBLING_EXIT_FAILURE 0xbadface
220#define SIBLING_EXIT_NEWPRIVS 0xbadfeed
221
222TEST(mode_strict_support)
223{
224 long ret;
225
226 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
227 ASSERT_EQ(0, ret) {
228 TH_LOG("Kernel does not support CONFIG_SECCOMP");
229 }
Mickaël Salaün369130b2017-08-07 01:23:37 +0200230 syscall(__NR_exit, 0);
Kees Cookc99ee512015-06-16 10:54:14 -0700231}
232
233TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
234{
235 long ret;
236
237 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
238 ASSERT_EQ(0, ret) {
239 TH_LOG("Kernel does not support CONFIG_SECCOMP");
240 }
241 syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
242 NULL, NULL, NULL);
243 EXPECT_FALSE(true) {
244 TH_LOG("Unreachable!");
245 }
246}
247
248/* Note! This doesn't test no new privs behavior */
249TEST(no_new_privs_support)
250{
251 long ret;
252
253 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
254 EXPECT_EQ(0, ret) {
255 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
256 }
257}
258
Kees Cookf3f6e302017-08-02 14:08:39 -0700259/* Tests kernel support by checking for a copy_from_user() fault on NULL. */
Kees Cookc99ee512015-06-16 10:54:14 -0700260TEST(mode_filter_support)
261{
262 long ret;
263
264 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
265 ASSERT_EQ(0, ret) {
266 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
267 }
268 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
269 EXPECT_EQ(-1, ret);
270 EXPECT_EQ(EFAULT, errno) {
271 TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
272 }
273}
274
275TEST(mode_filter_without_nnp)
276{
277 struct sock_filter filter[] = {
278 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
279 };
280 struct sock_fprog prog = {
281 .len = (unsigned short)ARRAY_SIZE(filter),
282 .filter = filter,
283 };
284 long ret;
285
286 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
287 ASSERT_LE(0, ret) {
288 TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
289 }
290 errno = 0;
291 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
292 /* Succeeds with CAP_SYS_ADMIN, fails without */
293 /* TODO(wad) check caps not euid */
294 if (geteuid()) {
295 EXPECT_EQ(-1, ret);
296 EXPECT_EQ(EACCES, errno);
297 } else {
298 EXPECT_EQ(0, ret);
299 }
300}
301
302#define MAX_INSNS_PER_PATH 32768
303
304TEST(filter_size_limits)
305{
306 int i;
307 int count = BPF_MAXINSNS + 1;
308 struct sock_filter allow[] = {
309 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
310 };
311 struct sock_filter *filter;
312 struct sock_fprog prog = { };
313 long ret;
314
315 filter = calloc(count, sizeof(*filter));
316 ASSERT_NE(NULL, filter);
317
318 for (i = 0; i < count; i++)
319 filter[i] = allow[0];
320
321 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
322 ASSERT_EQ(0, ret);
323
324 prog.filter = filter;
325 prog.len = count;
326
327 /* Too many filter instructions in a single filter. */
328 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
329 ASSERT_NE(0, ret) {
330 TH_LOG("Installing %d insn filter was allowed", prog.len);
331 }
332
333 /* One less is okay, though. */
334 prog.len -= 1;
335 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
336 ASSERT_EQ(0, ret) {
337 TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
338 }
339}
340
341TEST(filter_chain_limits)
342{
343 int i;
344 int count = BPF_MAXINSNS;
345 struct sock_filter allow[] = {
346 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
347 };
348 struct sock_filter *filter;
349 struct sock_fprog prog = { };
350 long ret;
351
352 filter = calloc(count, sizeof(*filter));
353 ASSERT_NE(NULL, filter);
354
355 for (i = 0; i < count; i++)
356 filter[i] = allow[0];
357
358 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
359 ASSERT_EQ(0, ret);
360
361 prog.filter = filter;
362 prog.len = 1;
363
364 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
365 ASSERT_EQ(0, ret);
366
367 prog.len = count;
368
369 /* Too many total filter instructions. */
370 for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
371 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
372 if (ret != 0)
373 break;
374 }
375 ASSERT_NE(0, ret) {
376 TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
377 i, count, i * (count + 4));
378 }
379}
380
381TEST(mode_filter_cannot_move_to_strict)
382{
383 struct sock_filter filter[] = {
384 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
385 };
386 struct sock_fprog prog = {
387 .len = (unsigned short)ARRAY_SIZE(filter),
388 .filter = filter,
389 };
390 long ret;
391
392 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
393 ASSERT_EQ(0, ret);
394
395 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
396 ASSERT_EQ(0, ret);
397
398 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
399 EXPECT_EQ(-1, ret);
400 EXPECT_EQ(EINVAL, errno);
401}
402
403
404TEST(mode_filter_get_seccomp)
405{
406 struct sock_filter filter[] = {
407 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
408 };
409 struct sock_fprog prog = {
410 .len = (unsigned short)ARRAY_SIZE(filter),
411 .filter = filter,
412 };
413 long ret;
414
415 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
416 ASSERT_EQ(0, ret);
417
418 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
419 EXPECT_EQ(0, ret);
420
421 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
422 ASSERT_EQ(0, ret);
423
424 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
425 EXPECT_EQ(2, ret);
426}
427
428
429TEST(ALLOW_all)
430{
431 struct sock_filter filter[] = {
432 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
433 };
434 struct sock_fprog prog = {
435 .len = (unsigned short)ARRAY_SIZE(filter),
436 .filter = filter,
437 };
438 long ret;
439
440 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
441 ASSERT_EQ(0, ret);
442
443 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
444 ASSERT_EQ(0, ret);
445}
446
447TEST(empty_prog)
448{
449 struct sock_filter filter[] = {
450 };
451 struct sock_fprog prog = {
452 .len = (unsigned short)ARRAY_SIZE(filter),
453 .filter = filter,
454 };
455 long ret;
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 EXPECT_EQ(-1, ret);
462 EXPECT_EQ(EINVAL, errno);
463}
464
Tyler Hicks59f5cf42017-08-11 04:33:57 +0000465TEST(log_all)
466{
467 struct sock_filter filter[] = {
468 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
469 };
470 struct sock_fprog prog = {
471 .len = (unsigned short)ARRAY_SIZE(filter),
472 .filter = filter,
473 };
474 long ret;
475 pid_t parent = getppid();
476
477 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
478 ASSERT_EQ(0, ret);
479
480 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
481 ASSERT_EQ(0, ret);
482
483 /* getppid() should succeed and be logged (no check for logging) */
484 EXPECT_EQ(parent, syscall(__NR_getppid));
485}
486
Kees Cookc99ee512015-06-16 10:54:14 -0700487TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
488{
489 struct sock_filter filter[] = {
490 BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
491 };
492 struct sock_fprog prog = {
493 .len = (unsigned short)ARRAY_SIZE(filter),
494 .filter = filter,
495 };
496 long ret;
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 EXPECT_EQ(0, syscall(__NR_getpid)) {
504 TH_LOG("getpid() shouldn't ever return");
505 }
506}
507
508/* return code >= 0x80000000 is unused. */
509TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
510{
511 struct sock_filter filter[] = {
512 BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
513 };
514 struct sock_fprog prog = {
515 .len = (unsigned short)ARRAY_SIZE(filter),
516 .filter = filter,
517 };
518 long ret;
519
520 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
521 ASSERT_EQ(0, ret);
522
523 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
524 ASSERT_EQ(0, ret);
525 EXPECT_EQ(0, syscall(__NR_getpid)) {
526 TH_LOG("getpid() shouldn't ever return");
527 }
528}
529
530TEST_SIGNAL(KILL_all, SIGSYS)
531{
532 struct sock_filter filter[] = {
533 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
534 };
535 struct sock_fprog prog = {
536 .len = (unsigned short)ARRAY_SIZE(filter),
537 .filter = filter,
538 };
539 long ret;
540
541 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
542 ASSERT_EQ(0, ret);
543
544 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
545 ASSERT_EQ(0, ret);
546}
547
548TEST_SIGNAL(KILL_one, SIGSYS)
549{
550 struct sock_filter filter[] = {
551 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
552 offsetof(struct seccomp_data, nr)),
553 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
554 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
555 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
556 };
557 struct sock_fprog prog = {
558 .len = (unsigned short)ARRAY_SIZE(filter),
559 .filter = filter,
560 };
561 long ret;
562 pid_t parent = getppid();
563
564 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
565 ASSERT_EQ(0, ret);
566
567 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
568 ASSERT_EQ(0, ret);
569
570 EXPECT_EQ(parent, syscall(__NR_getppid));
571 /* getpid() should never return. */
572 EXPECT_EQ(0, syscall(__NR_getpid));
573}
574
575TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
576{
Robert Sesekfd88d162015-11-02 15:28:49 -0500577 void *fatal_address;
Kees Cookc99ee512015-06-16 10:54:14 -0700578 struct sock_filter filter[] = {
579 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
580 offsetof(struct seccomp_data, nr)),
Robert Sesekfd88d162015-11-02 15:28:49 -0500581 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0),
Kees Cookc99ee512015-06-16 10:54:14 -0700582 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
583 /* Only both with lower 32-bit for now. */
584 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
Robert Sesekfd88d162015-11-02 15:28:49 -0500585 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
586 (unsigned long)&fatal_address, 0, 1),
Kees Cookc99ee512015-06-16 10:54:14 -0700587 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
588 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
589 };
590 struct sock_fprog prog = {
591 .len = (unsigned short)ARRAY_SIZE(filter),
592 .filter = filter,
593 };
594 long ret;
595 pid_t parent = getppid();
Robert Sesekfd88d162015-11-02 15:28:49 -0500596 struct tms timebuf;
597 clock_t clock = times(&timebuf);
Kees Cookc99ee512015-06-16 10:54:14 -0700598
599 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
600 ASSERT_EQ(0, ret);
601
602 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
603 ASSERT_EQ(0, ret);
604
605 EXPECT_EQ(parent, syscall(__NR_getppid));
Robert Sesekfd88d162015-11-02 15:28:49 -0500606 EXPECT_LE(clock, syscall(__NR_times, &timebuf));
607 /* times() should never return. */
608 EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
Kees Cookc99ee512015-06-16 10:54:14 -0700609}
610
611TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
612{
Robert Sesekfd88d162015-11-02 15:28:49 -0500613#ifndef __NR_mmap2
614 int sysno = __NR_mmap;
615#else
616 int sysno = __NR_mmap2;
617#endif
Kees Cookc99ee512015-06-16 10:54:14 -0700618 struct sock_filter filter[] = {
619 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
620 offsetof(struct seccomp_data, nr)),
Robert Sesekfd88d162015-11-02 15:28:49 -0500621 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0),
Kees Cookc99ee512015-06-16 10:54:14 -0700622 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
623 /* Only both with lower 32-bit for now. */
624 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
625 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
626 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
627 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
628 };
629 struct sock_fprog prog = {
630 .len = (unsigned short)ARRAY_SIZE(filter),
631 .filter = filter,
632 };
633 long ret;
634 pid_t parent = getppid();
Robert Sesekfd88d162015-11-02 15:28:49 -0500635 int fd;
636 void *map1, *map2;
Bamvor Jian Zhang2ce47b42015-11-13 11:17:51 +0800637 int page_size = sysconf(_SC_PAGESIZE);
638
639 ASSERT_LT(0, page_size);
Kees Cookc99ee512015-06-16 10:54:14 -0700640
641 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
642 ASSERT_EQ(0, ret);
643
644 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
645 ASSERT_EQ(0, ret);
646
Robert Sesekfd88d162015-11-02 15:28:49 -0500647 fd = open("/dev/zero", O_RDONLY);
648 ASSERT_NE(-1, fd);
649
Kees Cookc99ee512015-06-16 10:54:14 -0700650 EXPECT_EQ(parent, syscall(__NR_getppid));
Robert Sesekfd88d162015-11-02 15:28:49 -0500651 map1 = (void *)syscall(sysno,
Bamvor Jian Zhang2ce47b42015-11-13 11:17:51 +0800652 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
Robert Sesekfd88d162015-11-02 15:28:49 -0500653 EXPECT_NE(MAP_FAILED, map1);
654 /* mmap2() should never return. */
655 map2 = (void *)syscall(sysno,
Bamvor Jian Zhang2ce47b42015-11-13 11:17:51 +0800656 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
Robert Sesekfd88d162015-11-02 15:28:49 -0500657 EXPECT_EQ(MAP_FAILED, map2);
658
659 /* The test failed, so clean up the resources. */
Bamvor Jian Zhang2ce47b42015-11-13 11:17:51 +0800660 munmap(map1, page_size);
661 munmap(map2, page_size);
Robert Sesekfd88d162015-11-02 15:28:49 -0500662 close(fd);
Kees Cookc99ee512015-06-16 10:54:14 -0700663}
664
Kees Cookf3e18212017-08-11 13:20:33 -0700665/* This is a thread task to die via seccomp filter violation. */
666void *kill_thread(void *data)
667{
668 bool die = (bool)data;
669
670 if (die) {
671 prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
672 return (void *)SIBLING_EXIT_FAILURE;
673 }
674
675 return (void *)SIBLING_EXIT_UNKILLED;
676}
677
678/* Prepare a thread that will kill itself or both of us. */
679void kill_thread_or_group(struct __test_metadata *_metadata, bool kill_process)
680{
681 pthread_t thread;
682 void *status;
683 /* Kill only when calling __NR_prctl. */
684 struct sock_filter filter_thread[] = {
685 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
686 offsetof(struct seccomp_data, nr)),
687 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
688 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
689 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
690 };
691 struct sock_fprog prog_thread = {
692 .len = (unsigned short)ARRAY_SIZE(filter_thread),
693 .filter = filter_thread,
694 };
695 struct sock_filter filter_process[] = {
696 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
697 offsetof(struct seccomp_data, nr)),
698 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
699 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_PROCESS),
700 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
701 };
702 struct sock_fprog prog_process = {
703 .len = (unsigned short)ARRAY_SIZE(filter_process),
704 .filter = filter_process,
705 };
706
707 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
708 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
709 }
710
711 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
712 kill_process ? &prog_process : &prog_thread));
713
714 /*
715 * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
716 * flag cannot be downgraded by a new filter.
717 */
718 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
719
720 /* Start a thread that will exit immediately. */
721 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
722 ASSERT_EQ(0, pthread_join(thread, &status));
723 ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
724
725 /* Start a thread that will die immediately. */
726 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
727 ASSERT_EQ(0, pthread_join(thread, &status));
728 ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
729
730 /*
731 * If we get here, only the spawned thread died. Let the parent know
732 * the whole process didn't die (i.e. this thread, the spawner,
733 * stayed running).
734 */
735 exit(42);
736}
737
738TEST(KILL_thread)
739{
740 int status;
741 pid_t child_pid;
742
743 child_pid = fork();
744 ASSERT_LE(0, child_pid);
745 if (child_pid == 0) {
746 kill_thread_or_group(_metadata, false);
747 _exit(38);
748 }
749
750 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
751
752 /* If only the thread was killed, we'll see exit 42. */
753 ASSERT_TRUE(WIFEXITED(status));
754 ASSERT_EQ(42, WEXITSTATUS(status));
755}
756
757TEST(KILL_process)
758{
759 int status;
760 pid_t child_pid;
761
762 child_pid = fork();
763 ASSERT_LE(0, child_pid);
764 if (child_pid == 0) {
765 kill_thread_or_group(_metadata, true);
766 _exit(38);
767 }
768
769 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
770
771 /* If the entire process was killed, we'll see SIGSYS. */
772 ASSERT_TRUE(WIFSIGNALED(status));
773 ASSERT_EQ(SIGSYS, WTERMSIG(status));
774}
775
Kees Cookc99ee512015-06-16 10:54:14 -0700776/* TODO(wad) add 64-bit versus 32-bit arg tests. */
777TEST(arg_out_of_range)
778{
779 struct sock_filter filter[] = {
780 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
781 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
782 };
783 struct sock_fprog prog = {
784 .len = (unsigned short)ARRAY_SIZE(filter),
785 .filter = filter,
786 };
787 long ret;
788
789 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
790 ASSERT_EQ(0, ret);
791
792 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
793 EXPECT_EQ(-1, ret);
794 EXPECT_EQ(EINVAL, errno);
795}
796
Kees Cookf3f6e302017-08-02 14:08:39 -0700797#define ERRNO_FILTER(name, errno) \
798 struct sock_filter _read_filter_##name[] = { \
799 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, \
800 offsetof(struct seccomp_data, nr)), \
801 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), \
802 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | errno), \
803 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), \
804 }; \
805 struct sock_fprog prog_##name = { \
806 .len = (unsigned short)ARRAY_SIZE(_read_filter_##name), \
807 .filter = _read_filter_##name, \
808 }
809
810/* Make sure basic errno values are correctly passed through a filter. */
Kees Cookc99ee512015-06-16 10:54:14 -0700811TEST(ERRNO_valid)
812{
Kees Cookf3f6e302017-08-02 14:08:39 -0700813 ERRNO_FILTER(valid, E2BIG);
Kees Cookc99ee512015-06-16 10:54:14 -0700814 long ret;
815 pid_t parent = getppid();
816
817 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
818 ASSERT_EQ(0, ret);
819
Kees Cookf3f6e302017-08-02 14:08:39 -0700820 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_valid);
Kees Cookc99ee512015-06-16 10:54:14 -0700821 ASSERT_EQ(0, ret);
822
823 EXPECT_EQ(parent, syscall(__NR_getppid));
824 EXPECT_EQ(-1, read(0, NULL, 0));
825 EXPECT_EQ(E2BIG, errno);
826}
827
Kees Cookf3f6e302017-08-02 14:08:39 -0700828/* Make sure an errno of zero is correctly handled by the arch code. */
Kees Cookc99ee512015-06-16 10:54:14 -0700829TEST(ERRNO_zero)
830{
Kees Cookf3f6e302017-08-02 14:08:39 -0700831 ERRNO_FILTER(zero, 0);
Kees Cookc99ee512015-06-16 10:54:14 -0700832 long ret;
833 pid_t parent = getppid();
834
835 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
836 ASSERT_EQ(0, ret);
837
Kees Cookf3f6e302017-08-02 14:08:39 -0700838 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_zero);
Kees Cookc99ee512015-06-16 10:54:14 -0700839 ASSERT_EQ(0, ret);
840
841 EXPECT_EQ(parent, syscall(__NR_getppid));
842 /* "errno" of 0 is ok. */
843 EXPECT_EQ(0, read(0, NULL, 0));
844}
845
Kees Cookf3f6e302017-08-02 14:08:39 -0700846/*
847 * The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
848 * This tests that the errno value gets capped correctly, fixed by
849 * 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
850 */
Kees Cookc99ee512015-06-16 10:54:14 -0700851TEST(ERRNO_capped)
852{
Kees Cookf3f6e302017-08-02 14:08:39 -0700853 ERRNO_FILTER(capped, 4096);
Kees Cookc99ee512015-06-16 10:54:14 -0700854 long ret;
855 pid_t parent = getppid();
856
857 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
858 ASSERT_EQ(0, ret);
859
Kees Cookf3f6e302017-08-02 14:08:39 -0700860 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_capped);
Kees Cookc99ee512015-06-16 10:54:14 -0700861 ASSERT_EQ(0, ret);
862
863 EXPECT_EQ(parent, syscall(__NR_getppid));
864 EXPECT_EQ(-1, read(0, NULL, 0));
865 EXPECT_EQ(4095, errno);
866}
867
Kees Cookf3f6e302017-08-02 14:08:39 -0700868/*
869 * Filters are processed in reverse order: last applied is executed first.
870 * Since only the SECCOMP_RET_ACTION mask is tested for return values, the
871 * SECCOMP_RET_DATA mask results will follow the most recently applied
872 * matching filter return (and not the lowest or highest value).
873 */
874TEST(ERRNO_order)
875{
876 ERRNO_FILTER(first, 11);
877 ERRNO_FILTER(second, 13);
878 ERRNO_FILTER(third, 12);
879 long ret;
880 pid_t parent = getppid();
881
882 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
883 ASSERT_EQ(0, ret);
884
885 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_first);
886 ASSERT_EQ(0, ret);
887
888 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_second);
889 ASSERT_EQ(0, ret);
890
891 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_third);
892 ASSERT_EQ(0, ret);
893
894 EXPECT_EQ(parent, syscall(__NR_getppid));
895 EXPECT_EQ(-1, read(0, NULL, 0));
896 EXPECT_EQ(12, errno);
897}
898
Kees Cookc99ee512015-06-16 10:54:14 -0700899FIXTURE_DATA(TRAP) {
900 struct sock_fprog prog;
901};
902
903FIXTURE_SETUP(TRAP)
904{
905 struct sock_filter filter[] = {
906 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
907 offsetof(struct seccomp_data, nr)),
908 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
909 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
910 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
911 };
912
913 memset(&self->prog, 0, sizeof(self->prog));
914 self->prog.filter = malloc(sizeof(filter));
915 ASSERT_NE(NULL, self->prog.filter);
916 memcpy(self->prog.filter, filter, sizeof(filter));
917 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
918}
919
920FIXTURE_TEARDOWN(TRAP)
921{
922 if (self->prog.filter)
923 free(self->prog.filter);
924}
925
926TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
927{
928 long ret;
929
930 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
931 ASSERT_EQ(0, ret);
932
933 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
934 ASSERT_EQ(0, ret);
935 syscall(__NR_getpid);
936}
937
938/* Ensure that SIGSYS overrides SIG_IGN */
939TEST_F_SIGNAL(TRAP, ign, SIGSYS)
940{
941 long ret;
942
943 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
944 ASSERT_EQ(0, ret);
945
946 signal(SIGSYS, SIG_IGN);
947
948 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
949 ASSERT_EQ(0, ret);
950 syscall(__NR_getpid);
951}
952
Kees Cook10859f32017-09-07 16:32:46 -0700953static siginfo_t TRAP_info;
Kees Cookc99ee512015-06-16 10:54:14 -0700954static volatile int TRAP_nr;
955static void TRAP_action(int nr, siginfo_t *info, void *void_context)
956{
957 memcpy(&TRAP_info, info, sizeof(TRAP_info));
958 TRAP_nr = nr;
959}
960
961TEST_F(TRAP, handler)
962{
963 int ret, test;
964 struct sigaction act;
965 sigset_t mask;
966
967 memset(&act, 0, sizeof(act));
968 sigemptyset(&mask);
969 sigaddset(&mask, SIGSYS);
970
971 act.sa_sigaction = &TRAP_action;
972 act.sa_flags = SA_SIGINFO;
973 ret = sigaction(SIGSYS, &act, NULL);
974 ASSERT_EQ(0, ret) {
975 TH_LOG("sigaction failed");
976 }
977 ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
978 ASSERT_EQ(0, ret) {
979 TH_LOG("sigprocmask failed");
980 }
981
982 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
983 ASSERT_EQ(0, ret);
984 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
985 ASSERT_EQ(0, ret);
986 TRAP_nr = 0;
987 memset(&TRAP_info, 0, sizeof(TRAP_info));
988 /* Expect the registers to be rolled back. (nr = error) may vary
989 * based on arch. */
990 ret = syscall(__NR_getpid);
991 /* Silence gcc warning about volatile. */
992 test = TRAP_nr;
993 EXPECT_EQ(SIGSYS, test);
994 struct local_sigsys {
995 void *_call_addr; /* calling user insn */
996 int _syscall; /* triggering system call number */
997 unsigned int _arch; /* AUDIT_ARCH_* of syscall */
998 } *sigsys = (struct local_sigsys *)
999#ifdef si_syscall
1000 &(TRAP_info.si_call_addr);
1001#else
1002 &TRAP_info.si_pid;
1003#endif
1004 EXPECT_EQ(__NR_getpid, sigsys->_syscall);
1005 /* Make sure arch is non-zero. */
1006 EXPECT_NE(0, sigsys->_arch);
1007 EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
1008}
1009
1010FIXTURE_DATA(precedence) {
1011 struct sock_fprog allow;
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001012 struct sock_fprog log;
Kees Cookc99ee512015-06-16 10:54:14 -07001013 struct sock_fprog trace;
1014 struct sock_fprog error;
1015 struct sock_fprog trap;
1016 struct sock_fprog kill;
1017};
1018
1019FIXTURE_SETUP(precedence)
1020{
1021 struct sock_filter allow_insns[] = {
1022 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1023 };
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001024 struct sock_filter log_insns[] = {
1025 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1026 offsetof(struct seccomp_data, nr)),
1027 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1028 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1029 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
1030 };
Kees Cookc99ee512015-06-16 10:54:14 -07001031 struct sock_filter trace_insns[] = {
1032 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1033 offsetof(struct seccomp_data, nr)),
1034 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1035 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1036 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE),
1037 };
1038 struct sock_filter error_insns[] = {
1039 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1040 offsetof(struct seccomp_data, nr)),
1041 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1042 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1043 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO),
1044 };
1045 struct sock_filter trap_insns[] = {
1046 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1047 offsetof(struct seccomp_data, nr)),
1048 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1049 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1050 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
1051 };
1052 struct sock_filter kill_insns[] = {
1053 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1054 offsetof(struct seccomp_data, nr)),
1055 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1056 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1057 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1058 };
1059
1060 memset(self, 0, sizeof(*self));
1061#define FILTER_ALLOC(_x) \
1062 self->_x.filter = malloc(sizeof(_x##_insns)); \
1063 ASSERT_NE(NULL, self->_x.filter); \
1064 memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
1065 self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
1066 FILTER_ALLOC(allow);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001067 FILTER_ALLOC(log);
Kees Cookc99ee512015-06-16 10:54:14 -07001068 FILTER_ALLOC(trace);
1069 FILTER_ALLOC(error);
1070 FILTER_ALLOC(trap);
1071 FILTER_ALLOC(kill);
1072}
1073
1074FIXTURE_TEARDOWN(precedence)
1075{
1076#define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
1077 FILTER_FREE(allow);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001078 FILTER_FREE(log);
Kees Cookc99ee512015-06-16 10:54:14 -07001079 FILTER_FREE(trace);
1080 FILTER_FREE(error);
1081 FILTER_FREE(trap);
1082 FILTER_FREE(kill);
1083}
1084
1085TEST_F(precedence, allow_ok)
1086{
1087 pid_t parent, res = 0;
1088 long ret;
1089
1090 parent = getppid();
1091 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1092 ASSERT_EQ(0, ret);
1093
1094 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1095 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001096 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1097 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001098 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1099 ASSERT_EQ(0, ret);
1100 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1101 ASSERT_EQ(0, ret);
1102 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1103 ASSERT_EQ(0, ret);
1104 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1105 ASSERT_EQ(0, ret);
1106 /* Should work just fine. */
1107 res = syscall(__NR_getppid);
1108 EXPECT_EQ(parent, res);
1109}
1110
1111TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
1112{
1113 pid_t parent, res = 0;
1114 long ret;
1115
1116 parent = getppid();
1117 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1118 ASSERT_EQ(0, ret);
1119
1120 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1121 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001122 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1123 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001124 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1125 ASSERT_EQ(0, ret);
1126 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1127 ASSERT_EQ(0, ret);
1128 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1129 ASSERT_EQ(0, ret);
1130 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1131 ASSERT_EQ(0, ret);
1132 /* Should work just fine. */
1133 res = syscall(__NR_getppid);
1134 EXPECT_EQ(parent, res);
1135 /* getpid() should never return. */
1136 res = syscall(__NR_getpid);
1137 EXPECT_EQ(0, res);
1138}
1139
1140TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
1141{
1142 pid_t parent;
1143 long ret;
1144
1145 parent = getppid();
1146 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1147 ASSERT_EQ(0, ret);
1148
1149 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1150 ASSERT_EQ(0, ret);
1151 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1152 ASSERT_EQ(0, ret);
1153 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1154 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001155 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1156 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001157 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1158 ASSERT_EQ(0, ret);
1159 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1160 ASSERT_EQ(0, ret);
1161 /* Should work just fine. */
1162 EXPECT_EQ(parent, syscall(__NR_getppid));
1163 /* getpid() should never return. */
1164 EXPECT_EQ(0, syscall(__NR_getpid));
1165}
1166
1167TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
1168{
1169 pid_t parent;
1170 long ret;
1171
1172 parent = getppid();
1173 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1174 ASSERT_EQ(0, ret);
1175
1176 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1177 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001178 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1179 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001180 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1181 ASSERT_EQ(0, ret);
1182 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1183 ASSERT_EQ(0, ret);
1184 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1185 ASSERT_EQ(0, ret);
1186 /* Should work just fine. */
1187 EXPECT_EQ(parent, syscall(__NR_getppid));
1188 /* getpid() should never return. */
1189 EXPECT_EQ(0, syscall(__NR_getpid));
1190}
1191
1192TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
1193{
1194 pid_t parent;
1195 long ret;
1196
1197 parent = getppid();
1198 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1199 ASSERT_EQ(0, ret);
1200
1201 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1202 ASSERT_EQ(0, ret);
1203 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1204 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001205 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1206 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001207 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1208 ASSERT_EQ(0, ret);
1209 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1210 ASSERT_EQ(0, ret);
1211 /* Should work just fine. */
1212 EXPECT_EQ(parent, syscall(__NR_getppid));
1213 /* getpid() should never return. */
1214 EXPECT_EQ(0, syscall(__NR_getpid));
1215}
1216
1217TEST_F(precedence, errno_is_third)
1218{
1219 pid_t parent;
1220 long ret;
1221
1222 parent = getppid();
1223 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1224 ASSERT_EQ(0, ret);
1225
1226 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1227 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001228 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1229 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001230 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1231 ASSERT_EQ(0, ret);
1232 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1233 ASSERT_EQ(0, ret);
1234 /* Should work just fine. */
1235 EXPECT_EQ(parent, syscall(__NR_getppid));
1236 EXPECT_EQ(0, syscall(__NR_getpid));
1237}
1238
1239TEST_F(precedence, errno_is_third_in_any_order)
1240{
1241 pid_t parent;
1242 long ret;
1243
1244 parent = getppid();
1245 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1246 ASSERT_EQ(0, ret);
1247
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001248 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1249 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001250 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1251 ASSERT_EQ(0, ret);
1252 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1253 ASSERT_EQ(0, ret);
1254 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1255 ASSERT_EQ(0, ret);
1256 /* Should work just fine. */
1257 EXPECT_EQ(parent, syscall(__NR_getppid));
1258 EXPECT_EQ(0, syscall(__NR_getpid));
1259}
1260
1261TEST_F(precedence, trace_is_fourth)
1262{
1263 pid_t parent;
1264 long ret;
1265
1266 parent = getppid();
1267 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1268 ASSERT_EQ(0, ret);
1269
1270 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1271 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001272 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1273 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001274 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1275 ASSERT_EQ(0, ret);
1276 /* Should work just fine. */
1277 EXPECT_EQ(parent, syscall(__NR_getppid));
1278 /* No ptracer */
1279 EXPECT_EQ(-1, syscall(__NR_getpid));
1280}
1281
1282TEST_F(precedence, trace_is_fourth_in_any_order)
1283{
1284 pid_t parent;
1285 long ret;
1286
1287 parent = getppid();
1288 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1289 ASSERT_EQ(0, ret);
1290
1291 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1292 ASSERT_EQ(0, ret);
1293 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1294 ASSERT_EQ(0, ret);
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001295 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1296 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001297 /* Should work just fine. */
1298 EXPECT_EQ(parent, syscall(__NR_getppid));
1299 /* No ptracer */
1300 EXPECT_EQ(-1, syscall(__NR_getpid));
1301}
1302
Tyler Hicks59f5cf42017-08-11 04:33:57 +00001303TEST_F(precedence, log_is_fifth)
1304{
1305 pid_t mypid, parent;
1306 long ret;
1307
1308 mypid = getpid();
1309 parent = getppid();
1310 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1311 ASSERT_EQ(0, ret);
1312
1313 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1314 ASSERT_EQ(0, ret);
1315 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1316 ASSERT_EQ(0, ret);
1317 /* Should work just fine. */
1318 EXPECT_EQ(parent, syscall(__NR_getppid));
1319 /* Should also work just fine */
1320 EXPECT_EQ(mypid, syscall(__NR_getpid));
1321}
1322
1323TEST_F(precedence, log_is_fifth_in_any_order)
1324{
1325 pid_t mypid, parent;
1326 long ret;
1327
1328 mypid = getpid();
1329 parent = getppid();
1330 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1331 ASSERT_EQ(0, ret);
1332
1333 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1334 ASSERT_EQ(0, ret);
1335 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1336 ASSERT_EQ(0, ret);
1337 /* Should work just fine. */
1338 EXPECT_EQ(parent, syscall(__NR_getppid));
1339 /* Should also work just fine */
1340 EXPECT_EQ(mypid, syscall(__NR_getpid));
1341}
1342
Kees Cookc99ee512015-06-16 10:54:14 -07001343#ifndef PTRACE_O_TRACESECCOMP
1344#define PTRACE_O_TRACESECCOMP 0x00000080
1345#endif
1346
1347/* Catch the Ubuntu 12.04 value error. */
1348#if PTRACE_EVENT_SECCOMP != 7
1349#undef PTRACE_EVENT_SECCOMP
1350#endif
1351
1352#ifndef PTRACE_EVENT_SECCOMP
1353#define PTRACE_EVENT_SECCOMP 7
1354#endif
1355
1356#define IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP)
1357bool tracer_running;
1358void tracer_stop(int sig)
1359{
1360 tracer_running = false;
1361}
1362
1363typedef void tracer_func_t(struct __test_metadata *_metadata,
1364 pid_t tracee, int status, void *args);
1365
Kees Cook58d0a862016-05-26 11:47:01 -07001366void start_tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
1367 tracer_func_t tracer_func, void *args, bool ptrace_syscall)
Kees Cookc99ee512015-06-16 10:54:14 -07001368{
1369 int ret = -1;
1370 struct sigaction action = {
1371 .sa_handler = tracer_stop,
1372 };
1373
1374 /* Allow external shutdown. */
1375 tracer_running = true;
1376 ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));
1377
1378 errno = 0;
1379 while (ret == -1 && errno != EINVAL)
1380 ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
1381 ASSERT_EQ(0, ret) {
1382 kill(tracee, SIGKILL);
1383 }
1384 /* Wait for attach stop */
1385 wait(NULL);
1386
Kees Cook58d0a862016-05-26 11:47:01 -07001387 ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, ptrace_syscall ?
1388 PTRACE_O_TRACESYSGOOD :
1389 PTRACE_O_TRACESECCOMP);
Kees Cookc99ee512015-06-16 10:54:14 -07001390 ASSERT_EQ(0, ret) {
1391 TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
1392 kill(tracee, SIGKILL);
1393 }
Kees Cook58d0a862016-05-26 11:47:01 -07001394 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1395 tracee, NULL, 0);
1396 ASSERT_EQ(0, ret);
Kees Cookc99ee512015-06-16 10:54:14 -07001397
1398 /* Unblock the tracee */
1399 ASSERT_EQ(1, write(fd, "A", 1));
1400 ASSERT_EQ(0, close(fd));
1401
1402 /* Run until we're shut down. Must assert to stop execution. */
1403 while (tracer_running) {
1404 int status;
1405
1406 if (wait(&status) != tracee)
1407 continue;
1408 if (WIFSIGNALED(status) || WIFEXITED(status))
1409 /* Child is dead. Time to go. */
1410 return;
1411
Kees Cook58d0a862016-05-26 11:47:01 -07001412 /* Check if this is a seccomp event. */
1413 ASSERT_EQ(!ptrace_syscall, IS_SECCOMP_EVENT(status));
Kees Cookc99ee512015-06-16 10:54:14 -07001414
1415 tracer_func(_metadata, tracee, status, args);
1416
Kees Cook58d0a862016-05-26 11:47:01 -07001417 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1418 tracee, NULL, 0);
Kees Cookc99ee512015-06-16 10:54:14 -07001419 ASSERT_EQ(0, ret);
1420 }
1421 /* Directly report the status of our test harness results. */
1422 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
1423}
1424
1425/* Common tracer setup/teardown functions. */
1426void cont_handler(int num)
1427{ }
1428pid_t setup_trace_fixture(struct __test_metadata *_metadata,
Kees Cook58d0a862016-05-26 11:47:01 -07001429 tracer_func_t func, void *args, bool ptrace_syscall)
Kees Cookc99ee512015-06-16 10:54:14 -07001430{
1431 char sync;
1432 int pipefd[2];
1433 pid_t tracer_pid;
1434 pid_t tracee = getpid();
1435
1436 /* Setup a pipe for clean synchronization. */
1437 ASSERT_EQ(0, pipe(pipefd));
1438
1439 /* Fork a child which we'll promote to tracer */
1440 tracer_pid = fork();
1441 ASSERT_LE(0, tracer_pid);
1442 signal(SIGALRM, cont_handler);
1443 if (tracer_pid == 0) {
1444 close(pipefd[0]);
Kees Cook58d0a862016-05-26 11:47:01 -07001445 start_tracer(_metadata, pipefd[1], tracee, func, args,
1446 ptrace_syscall);
Kees Cookc99ee512015-06-16 10:54:14 -07001447 syscall(__NR_exit, 0);
1448 }
1449 close(pipefd[1]);
1450 prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
1451 read(pipefd[0], &sync, 1);
1452 close(pipefd[0]);
1453
1454 return tracer_pid;
1455}
1456void teardown_trace_fixture(struct __test_metadata *_metadata,
1457 pid_t tracer)
1458{
1459 if (tracer) {
1460 int status;
1461 /*
1462 * Extract the exit code from the other process and
1463 * adopt it for ourselves in case its asserts failed.
1464 */
1465 ASSERT_EQ(0, kill(tracer, SIGUSR1));
1466 ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
1467 if (WEXITSTATUS(status))
1468 _metadata->passed = 0;
1469 }
1470}
1471
1472/* "poke" tracer arguments and function. */
1473struct tracer_args_poke_t {
1474 unsigned long poke_addr;
1475};
1476
1477void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
1478 void *args)
1479{
1480 int ret;
1481 unsigned long msg;
1482 struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;
1483
1484 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1485 EXPECT_EQ(0, ret);
1486 /* If this fails, don't try to recover. */
1487 ASSERT_EQ(0x1001, msg) {
1488 kill(tracee, SIGKILL);
1489 }
1490 /*
1491 * Poke in the message.
1492 * Registers are not touched to try to keep this relatively arch
1493 * agnostic.
1494 */
1495 ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
1496 EXPECT_EQ(0, ret);
1497}
1498
1499FIXTURE_DATA(TRACE_poke) {
1500 struct sock_fprog prog;
1501 pid_t tracer;
1502 long poked;
1503 struct tracer_args_poke_t tracer_args;
1504};
1505
1506FIXTURE_SETUP(TRACE_poke)
1507{
1508 struct sock_filter filter[] = {
1509 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1510 offsetof(struct seccomp_data, nr)),
1511 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1512 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001),
1513 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1514 };
1515
1516 self->poked = 0;
1517 memset(&self->prog, 0, sizeof(self->prog));
1518 self->prog.filter = malloc(sizeof(filter));
1519 ASSERT_NE(NULL, self->prog.filter);
1520 memcpy(self->prog.filter, filter, sizeof(filter));
1521 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1522
1523 /* Set up tracer args. */
1524 self->tracer_args.poke_addr = (unsigned long)&self->poked;
1525
1526 /* Launch tracer. */
1527 self->tracer = setup_trace_fixture(_metadata, tracer_poke,
Kees Cook58d0a862016-05-26 11:47:01 -07001528 &self->tracer_args, false);
Kees Cookc99ee512015-06-16 10:54:14 -07001529}
1530
1531FIXTURE_TEARDOWN(TRACE_poke)
1532{
1533 teardown_trace_fixture(_metadata, self->tracer);
1534 if (self->prog.filter)
1535 free(self->prog.filter);
1536}
1537
1538TEST_F(TRACE_poke, read_has_side_effects)
1539{
1540 ssize_t ret;
1541
1542 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1543 ASSERT_EQ(0, ret);
1544
1545 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1546 ASSERT_EQ(0, ret);
1547
1548 EXPECT_EQ(0, self->poked);
1549 ret = read(-1, NULL, 0);
1550 EXPECT_EQ(-1, ret);
1551 EXPECT_EQ(0x1001, self->poked);
1552}
1553
1554TEST_F(TRACE_poke, getpid_runs_normally)
1555{
1556 long ret;
1557
1558 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1559 ASSERT_EQ(0, ret);
1560
1561 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1562 ASSERT_EQ(0, ret);
1563
1564 EXPECT_EQ(0, self->poked);
1565 EXPECT_NE(0, syscall(__NR_getpid));
1566 EXPECT_EQ(0, self->poked);
1567}
1568
1569#if defined(__x86_64__)
1570# define ARCH_REGS struct user_regs_struct
1571# define SYSCALL_NUM orig_rax
1572# define SYSCALL_RET rax
1573#elif defined(__i386__)
1574# define ARCH_REGS struct user_regs_struct
1575# define SYSCALL_NUM orig_eax
1576# define SYSCALL_RET eax
1577#elif defined(__arm__)
1578# define ARCH_REGS struct pt_regs
1579# define SYSCALL_NUM ARM_r7
1580# define SYSCALL_RET ARM_r0
1581#elif defined(__aarch64__)
1582# define ARCH_REGS struct user_pt_regs
1583# define SYSCALL_NUM regs[8]
1584# define SYSCALL_RET regs[0]
Helge Deller64e2a422016-04-01 22:40:53 +02001585#elif defined(__hppa__)
1586# define ARCH_REGS struct user_regs_struct
1587# define SYSCALL_NUM gr[20]
1588# define SYSCALL_RET gr[28]
Michael Ellerman5d83c2b2015-07-23 20:21:11 +10001589#elif defined(__powerpc__)
1590# define ARCH_REGS struct pt_regs
1591# define SYSCALL_NUM gpr[0]
1592# define SYSCALL_RET gpr[3]
Kees Cookb623c4d2015-08-21 11:22:35 -07001593#elif defined(__s390__)
1594# define ARCH_REGS s390_regs
1595# define SYSCALL_NUM gprs[2]
1596# define SYSCALL_RET gprs[2]
Matt Redfearn0ce105b2016-03-29 09:35:29 +01001597#elif defined(__mips__)
1598# define ARCH_REGS struct pt_regs
1599# define SYSCALL_NUM regs[2]
1600# define SYSCALL_SYSCALL_NUM regs[4]
1601# define SYSCALL_RET regs[2]
1602# define SYSCALL_NUM_RET_SHARE_REG
Kees Cookc99ee512015-06-16 10:54:14 -07001603#else
1604# error "Do not know how to find your architecture's registers and syscalls"
1605#endif
1606
Kees Cooka33b2d02016-08-08 17:46:23 -07001607/* When the syscall return can't be changed, stub out the tests for it. */
1608#ifdef SYSCALL_NUM_RET_SHARE_REG
1609# define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(-1, action)
1610#else
Kees Cooked5f1322019-01-25 10:33:59 -08001611# define EXPECT_SYSCALL_RETURN(val, action) \
1612 do { \
1613 errno = 0; \
1614 if (val < 0) { \
1615 EXPECT_EQ(-1, action); \
1616 EXPECT_EQ(-(val), errno); \
1617 } else { \
1618 EXPECT_EQ(val, action); \
1619 } \
1620 } while (0)
Kees Cooka33b2d02016-08-08 17:46:23 -07001621#endif
1622
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001623/* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1624 * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1625 */
Matt Redfearn0ce105b2016-03-29 09:35:29 +01001626#if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001627#define HAVE_GETREGS
1628#endif
1629
Kees Cookc99ee512015-06-16 10:54:14 -07001630/* Architecture-specific syscall fetching routine. */
1631int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1632{
Kees Cookc99ee512015-06-16 10:54:14 -07001633 ARCH_REGS regs;
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001634#ifdef HAVE_GETREGS
1635 EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
1636 TH_LOG("PTRACE_GETREGS failed");
1637 return -1;
1638 }
1639#else
1640 struct iovec iov;
Kees Cookc99ee512015-06-16 10:54:14 -07001641
1642 iov.iov_base = &regs;
1643 iov.iov_len = sizeof(regs);
1644 EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1645 TH_LOG("PTRACE_GETREGSET failed");
1646 return -1;
1647 }
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001648#endif
Kees Cookc99ee512015-06-16 10:54:14 -07001649
Matt Redfearn0ce105b2016-03-29 09:35:29 +01001650#if defined(__mips__)
1651 if (regs.SYSCALL_NUM == __NR_O32_Linux)
1652 return regs.SYSCALL_SYSCALL_NUM;
1653#endif
Kees Cookc99ee512015-06-16 10:54:14 -07001654 return regs.SYSCALL_NUM;
1655}
1656
1657/* Architecture-specific syscall changing routine. */
1658void change_syscall(struct __test_metadata *_metadata,
Kees Cooked5f1322019-01-25 10:33:59 -08001659 pid_t tracee, int syscall, int result)
Kees Cookc99ee512015-06-16 10:54:14 -07001660{
Kees Cookc99ee512015-06-16 10:54:14 -07001661 int ret;
1662 ARCH_REGS regs;
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001663#ifdef HAVE_GETREGS
1664 ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
1665#else
1666 struct iovec iov;
Kees Cookc99ee512015-06-16 10:54:14 -07001667 iov.iov_base = &regs;
1668 iov.iov_len = sizeof(regs);
1669 ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001670#endif
Mickaël Salaün34a048c2017-06-11 14:32:58 +02001671 EXPECT_EQ(0, ret) {}
Kees Cookc99ee512015-06-16 10:54:14 -07001672
Kees Cook256d0af2015-10-06 12:30:25 -07001673#if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
Helge Deller64e2a422016-04-01 22:40:53 +02001674 defined(__s390__) || defined(__hppa__)
Kees Cookc99ee512015-06-16 10:54:14 -07001675 {
1676 regs.SYSCALL_NUM = syscall;
1677 }
Matt Redfearn0ce105b2016-03-29 09:35:29 +01001678#elif defined(__mips__)
1679 {
1680 if (regs.SYSCALL_NUM == __NR_O32_Linux)
1681 regs.SYSCALL_SYSCALL_NUM = syscall;
1682 else
1683 regs.SYSCALL_NUM = syscall;
1684 }
Kees Cookc99ee512015-06-16 10:54:14 -07001685
1686#elif defined(__arm__)
1687# ifndef PTRACE_SET_SYSCALL
1688# define PTRACE_SET_SYSCALL 23
1689# endif
1690 {
1691 ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
1692 EXPECT_EQ(0, ret);
1693 }
1694
Kees Cook256d0af2015-10-06 12:30:25 -07001695#elif defined(__aarch64__)
1696# ifndef NT_ARM_SYSTEM_CALL
1697# define NT_ARM_SYSTEM_CALL 0x404
1698# endif
1699 {
1700 iov.iov_base = &syscall;
1701 iov.iov_len = sizeof(syscall);
1702 ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
1703 &iov);
1704 EXPECT_EQ(0, ret);
1705 }
1706
Kees Cookc99ee512015-06-16 10:54:14 -07001707#else
1708 ASSERT_EQ(1, 0) {
1709 TH_LOG("How is the syscall changed on this architecture?");
1710 }
1711#endif
1712
1713 /* If syscall is skipped, change return value. */
1714 if (syscall == -1)
Matt Redfearn0ce105b2016-03-29 09:35:29 +01001715#ifdef SYSCALL_NUM_RET_SHARE_REG
1716 TH_LOG("Can't modify syscall return on this architecture");
1717#else
Kees Cooked5f1322019-01-25 10:33:59 -08001718 regs.SYSCALL_RET = result;
Matt Redfearn0ce105b2016-03-29 09:35:29 +01001719#endif
Kees Cookc99ee512015-06-16 10:54:14 -07001720
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001721#ifdef HAVE_GETREGS
1722 ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
1723#else
Kees Cook256d0af2015-10-06 12:30:25 -07001724 iov.iov_base = &regs;
1725 iov.iov_len = sizeof(regs);
Kees Cookc99ee512015-06-16 10:54:14 -07001726 ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
Mickaël Salaün4a0b8802015-12-29 21:35:45 +01001727#endif
Kees Cookc99ee512015-06-16 10:54:14 -07001728 EXPECT_EQ(0, ret);
1729}
1730
1731void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
1732 int status, void *args)
1733{
1734 int ret;
1735 unsigned long msg;
1736
1737 /* Make sure we got the right message. */
1738 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1739 EXPECT_EQ(0, ret);
1740
Kees Cookb623c4d2015-08-21 11:22:35 -07001741 /* Validate and take action on expected syscalls. */
Kees Cookc99ee512015-06-16 10:54:14 -07001742 switch (msg) {
1743 case 0x1002:
1744 /* change getpid to getppid. */
Kees Cookb623c4d2015-08-21 11:22:35 -07001745 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
Kees Cooked5f1322019-01-25 10:33:59 -08001746 change_syscall(_metadata, tracee, __NR_getppid, 0);
Kees Cookc99ee512015-06-16 10:54:14 -07001747 break;
1748 case 0x1003:
Kees Cooked5f1322019-01-25 10:33:59 -08001749 /* skip gettid with valid return code. */
Kees Cookb623c4d2015-08-21 11:22:35 -07001750 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
Kees Cooked5f1322019-01-25 10:33:59 -08001751 change_syscall(_metadata, tracee, -1, 45000);
Kees Cookc99ee512015-06-16 10:54:14 -07001752 break;
1753 case 0x1004:
Kees Cooked5f1322019-01-25 10:33:59 -08001754 /* skip openat with error. */
1755 EXPECT_EQ(__NR_openat, get_syscall(_metadata, tracee));
1756 change_syscall(_metadata, tracee, -1, -ESRCH);
1757 break;
1758 case 0x1005:
Kees Cookc99ee512015-06-16 10:54:14 -07001759 /* do nothing (allow getppid) */
Kees Cookb623c4d2015-08-21 11:22:35 -07001760 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
Kees Cookc99ee512015-06-16 10:54:14 -07001761 break;
1762 default:
1763 EXPECT_EQ(0, msg) {
1764 TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1765 kill(tracee, SIGKILL);
1766 }
1767 }
1768
1769}
1770
Kees Cook58d0a862016-05-26 11:47:01 -07001771void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
1772 int status, void *args)
1773{
1774 int ret, nr;
1775 unsigned long msg;
1776 static bool entry;
1777
1778 /* Make sure we got an empty message. */
1779 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1780 EXPECT_EQ(0, ret);
1781 EXPECT_EQ(0, msg);
1782
1783 /* The only way to tell PTRACE_SYSCALL entry/exit is by counting. */
1784 entry = !entry;
1785 if (!entry)
1786 return;
1787
1788 nr = get_syscall(_metadata, tracee);
1789
1790 if (nr == __NR_getpid)
Kees Cooked5f1322019-01-25 10:33:59 -08001791 change_syscall(_metadata, tracee, __NR_getppid, 0);
1792 if (nr == __NR_gettid)
1793 change_syscall(_metadata, tracee, -1, 45000);
Anders Roxell912ec312018-01-05 17:31:18 +01001794 if (nr == __NR_openat)
Kees Cooked5f1322019-01-25 10:33:59 -08001795 change_syscall(_metadata, tracee, -1, -ESRCH);
Kees Cook58d0a862016-05-26 11:47:01 -07001796}
1797
Kees Cookc99ee512015-06-16 10:54:14 -07001798FIXTURE_DATA(TRACE_syscall) {
1799 struct sock_fprog prog;
1800 pid_t tracer, mytid, mypid, parent;
1801};
1802
1803FIXTURE_SETUP(TRACE_syscall)
1804{
1805 struct sock_filter filter[] = {
1806 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1807 offsetof(struct seccomp_data, nr)),
1808 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1809 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1810 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1811 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
Kees Cooked5f1322019-01-25 10:33:59 -08001812 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_openat, 0, 1),
Kees Cookc99ee512015-06-16 10:54:14 -07001813 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
Kees Cooked5f1322019-01-25 10:33:59 -08001814 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1815 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1005),
Kees Cookc99ee512015-06-16 10:54:14 -07001816 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1817 };
1818
1819 memset(&self->prog, 0, sizeof(self->prog));
1820 self->prog.filter = malloc(sizeof(filter));
1821 ASSERT_NE(NULL, self->prog.filter);
1822 memcpy(self->prog.filter, filter, sizeof(filter));
1823 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1824
1825 /* Prepare some testable syscall results. */
1826 self->mytid = syscall(__NR_gettid);
1827 ASSERT_GT(self->mytid, 0);
1828 ASSERT_NE(self->mytid, 1) {
1829 TH_LOG("Running this test as init is not supported. :)");
1830 }
1831
1832 self->mypid = getpid();
1833 ASSERT_GT(self->mypid, 0);
1834 ASSERT_EQ(self->mytid, self->mypid);
1835
1836 self->parent = getppid();
1837 ASSERT_GT(self->parent, 0);
1838 ASSERT_NE(self->parent, self->mypid);
1839
1840 /* Launch tracer. */
Kees Cook58d0a862016-05-26 11:47:01 -07001841 self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL,
1842 false);
Kees Cookc99ee512015-06-16 10:54:14 -07001843}
1844
1845FIXTURE_TEARDOWN(TRACE_syscall)
1846{
1847 teardown_trace_fixture(_metadata, self->tracer);
1848 if (self->prog.filter)
1849 free(self->prog.filter);
1850}
1851
Kees Cooka33b2d02016-08-08 17:46:23 -07001852TEST_F(TRACE_syscall, ptrace_syscall_redirected)
1853{
1854 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1855 teardown_trace_fixture(_metadata, self->tracer);
1856 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1857 true);
1858
1859 /* Tracer will redirect getpid to getppid. */
1860 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1861}
1862
Kees Cooked5f1322019-01-25 10:33:59 -08001863TEST_F(TRACE_syscall, ptrace_syscall_errno)
Kees Cooka33b2d02016-08-08 17:46:23 -07001864{
1865 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1866 teardown_trace_fixture(_metadata, self->tracer);
1867 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1868 true);
1869
Kees Cooked5f1322019-01-25 10:33:59 -08001870 /* Tracer should skip the open syscall, resulting in ESRCH. */
1871 EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
1872}
1873
1874TEST_F(TRACE_syscall, ptrace_syscall_faked)
1875{
1876 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1877 teardown_trace_fixture(_metadata, self->tracer);
1878 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1879 true);
1880
1881 /* Tracer should skip the gettid syscall, resulting fake pid. */
1882 EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
Kees Cooka33b2d02016-08-08 17:46:23 -07001883}
1884
Kees Cookc99ee512015-06-16 10:54:14 -07001885TEST_F(TRACE_syscall, syscall_allowed)
1886{
1887 long ret;
1888
1889 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1890 ASSERT_EQ(0, ret);
1891
1892 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1893 ASSERT_EQ(0, ret);
1894
1895 /* getppid works as expected (no changes). */
1896 EXPECT_EQ(self->parent, syscall(__NR_getppid));
1897 EXPECT_NE(self->mypid, syscall(__NR_getppid));
1898}
1899
1900TEST_F(TRACE_syscall, syscall_redirected)
1901{
1902 long ret;
1903
1904 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1905 ASSERT_EQ(0, ret);
1906
1907 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1908 ASSERT_EQ(0, ret);
1909
1910 /* getpid has been redirected to getppid as expected. */
1911 EXPECT_EQ(self->parent, syscall(__NR_getpid));
1912 EXPECT_NE(self->mypid, syscall(__NR_getpid));
1913}
1914
Kees Cooked5f1322019-01-25 10:33:59 -08001915TEST_F(TRACE_syscall, syscall_errno)
1916{
1917 long ret;
1918
1919 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1920 ASSERT_EQ(0, ret);
1921
1922 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1923 ASSERT_EQ(0, ret);
1924
1925 /* openat has been skipped and an errno return. */
1926 EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
1927}
1928
1929TEST_F(TRACE_syscall, syscall_faked)
Kees Cookc99ee512015-06-16 10:54:14 -07001930{
1931 long ret;
1932
1933 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1934 ASSERT_EQ(0, ret);
1935
1936 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1937 ASSERT_EQ(0, ret);
1938
1939 /* gettid has been skipped and an altered return value stored. */
Kees Cooked5f1322019-01-25 10:33:59 -08001940 EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
Kees Cookc99ee512015-06-16 10:54:14 -07001941}
1942
Kees Cook58d0a862016-05-26 11:47:01 -07001943TEST_F(TRACE_syscall, skip_after_RET_TRACE)
1944{
1945 struct sock_filter filter[] = {
1946 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1947 offsetof(struct seccomp_data, nr)),
1948 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1949 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1950 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1951 };
1952 struct sock_fprog prog = {
1953 .len = (unsigned short)ARRAY_SIZE(filter),
1954 .filter = filter,
1955 };
1956 long ret;
1957
1958 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1959 ASSERT_EQ(0, ret);
1960
1961 /* Install fixture filter. */
1962 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1963 ASSERT_EQ(0, ret);
1964
1965 /* Install "errno on getppid" filter. */
1966 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1967 ASSERT_EQ(0, ret);
1968
1969 /* Tracer will redirect getpid to getppid, and we should see EPERM. */
Kees Cooka33b2d02016-08-08 17:46:23 -07001970 errno = 0;
Kees Cook58d0a862016-05-26 11:47:01 -07001971 EXPECT_EQ(-1, syscall(__NR_getpid));
1972 EXPECT_EQ(EPERM, errno);
1973}
1974
1975TEST_F_SIGNAL(TRACE_syscall, kill_after_RET_TRACE, SIGSYS)
1976{
1977 struct sock_filter filter[] = {
1978 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1979 offsetof(struct seccomp_data, nr)),
1980 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1981 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1982 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1983 };
1984 struct sock_fprog prog = {
1985 .len = (unsigned short)ARRAY_SIZE(filter),
1986 .filter = filter,
1987 };
1988 long ret;
1989
1990 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1991 ASSERT_EQ(0, ret);
1992
1993 /* Install fixture filter. */
1994 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1995 ASSERT_EQ(0, ret);
1996
1997 /* Install "death on getppid" filter. */
1998 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1999 ASSERT_EQ(0, ret);
2000
2001 /* Tracer will redirect getpid to getppid, and we should die. */
2002 EXPECT_NE(self->mypid, syscall(__NR_getpid));
2003}
2004
2005TEST_F(TRACE_syscall, skip_after_ptrace)
2006{
2007 struct sock_filter filter[] = {
2008 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2009 offsetof(struct seccomp_data, nr)),
2010 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2011 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
2012 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2013 };
2014 struct sock_fprog prog = {
2015 .len = (unsigned short)ARRAY_SIZE(filter),
2016 .filter = filter,
2017 };
2018 long ret;
2019
2020 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
2021 teardown_trace_fixture(_metadata, self->tracer);
2022 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
2023 true);
2024
2025 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2026 ASSERT_EQ(0, ret);
2027
2028 /* Install "errno on getppid" filter. */
2029 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2030 ASSERT_EQ(0, ret);
2031
2032 /* Tracer will redirect getpid to getppid, and we should see EPERM. */
2033 EXPECT_EQ(-1, syscall(__NR_getpid));
2034 EXPECT_EQ(EPERM, errno);
2035}
2036
2037TEST_F_SIGNAL(TRACE_syscall, kill_after_ptrace, SIGSYS)
2038{
2039 struct sock_filter filter[] = {
2040 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2041 offsetof(struct seccomp_data, nr)),
2042 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2043 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2044 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2045 };
2046 struct sock_fprog prog = {
2047 .len = (unsigned short)ARRAY_SIZE(filter),
2048 .filter = filter,
2049 };
2050 long ret;
2051
2052 /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
2053 teardown_trace_fixture(_metadata, self->tracer);
2054 self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
2055 true);
2056
2057 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2058 ASSERT_EQ(0, ret);
2059
2060 /* Install "death on getppid" filter. */
2061 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2062 ASSERT_EQ(0, ret);
2063
2064 /* Tracer will redirect getpid to getppid, and we should die. */
2065 EXPECT_NE(self->mypid, syscall(__NR_getpid));
2066}
2067
Kees Cookc99ee512015-06-16 10:54:14 -07002068TEST(seccomp_syscall)
2069{
2070 struct sock_filter filter[] = {
2071 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2072 };
2073 struct sock_fprog prog = {
2074 .len = (unsigned short)ARRAY_SIZE(filter),
2075 .filter = filter,
2076 };
2077 long ret;
2078
2079 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2080 ASSERT_EQ(0, ret) {
2081 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2082 }
2083
2084 /* Reject insane operation. */
2085 ret = seccomp(-1, 0, &prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002086 ASSERT_NE(ENOSYS, errno) {
2087 TH_LOG("Kernel does not support seccomp syscall!");
2088 }
Kees Cookc99ee512015-06-16 10:54:14 -07002089 EXPECT_EQ(EINVAL, errno) {
2090 TH_LOG("Did not reject crazy op value!");
2091 }
2092
2093 /* Reject strict with flags or pointer. */
2094 ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
2095 EXPECT_EQ(EINVAL, errno) {
2096 TH_LOG("Did not reject mode strict with flags!");
2097 }
2098 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
2099 EXPECT_EQ(EINVAL, errno) {
2100 TH_LOG("Did not reject mode strict with uargs!");
2101 }
2102
2103 /* Reject insane args for filter. */
2104 ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
2105 EXPECT_EQ(EINVAL, errno) {
2106 TH_LOG("Did not reject crazy filter flags!");
2107 }
2108 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
2109 EXPECT_EQ(EFAULT, errno) {
2110 TH_LOG("Did not reject NULL filter!");
2111 }
2112
2113 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2114 EXPECT_EQ(0, errno) {
2115 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
2116 strerror(errno));
2117 }
2118}
2119
2120TEST(seccomp_syscall_mode_lock)
2121{
2122 struct sock_filter filter[] = {
2123 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2124 };
2125 struct sock_fprog prog = {
2126 .len = (unsigned short)ARRAY_SIZE(filter),
2127 .filter = filter,
2128 };
2129 long ret;
2130
2131 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2132 ASSERT_EQ(0, ret) {
2133 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2134 }
2135
2136 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002137 ASSERT_NE(ENOSYS, errno) {
2138 TH_LOG("Kernel does not support seccomp syscall!");
2139 }
Kees Cookc99ee512015-06-16 10:54:14 -07002140 EXPECT_EQ(0, ret) {
2141 TH_LOG("Could not install filter!");
2142 }
2143
2144 /* Make sure neither entry point will switch to strict. */
2145 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
2146 EXPECT_EQ(EINVAL, errno) {
2147 TH_LOG("Switched to mode strict!");
2148 }
2149
2150 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
2151 EXPECT_EQ(EINVAL, errno) {
2152 TH_LOG("Switched to mode strict!");
2153 }
2154}
2155
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002156/*
2157 * Test detection of known and unknown filter flags. Userspace needs to be able
2158 * to check if a filter flag is supported by the current kernel and a good way
2159 * of doing that is by attempting to enter filter mode, with the flag bit in
2160 * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
2161 * that the flag is valid and EINVAL indicates that the flag is invalid.
2162 */
2163TEST(detect_seccomp_filter_flags)
2164{
Tyler Hickse66a3992017-08-11 04:33:56 +00002165 unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
Kees Cook00a02d02018-05-03 14:56:12 -07002166 SECCOMP_FILTER_FLAG_LOG,
Tycho Andersen6a21cc52018-12-09 11:24:13 -07002167 SECCOMP_FILTER_FLAG_SPEC_ALLOW,
2168 SECCOMP_FILTER_FLAG_NEW_LISTENER };
Kees Cook4ee07762019-04-24 09:32:55 -07002169 unsigned int exclusive[] = {
2170 SECCOMP_FILTER_FLAG_TSYNC,
2171 SECCOMP_FILTER_FLAG_NEW_LISTENER };
2172 unsigned int flag, all_flags, exclusive_mask;
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002173 int i;
2174 long ret;
2175
Kees Cook4ee07762019-04-24 09:32:55 -07002176 /* Test detection of individual known-good filter flags */
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002177 for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
Kees Cook00a02d02018-05-03 14:56:12 -07002178 int bits = 0;
2179
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002180 flag = flags[i];
Kees Cook00a02d02018-05-03 14:56:12 -07002181 /* Make sure the flag is a single bit! */
2182 while (flag) {
2183 if (flag & 0x1)
2184 bits ++;
2185 flag >>= 1;
2186 }
2187 ASSERT_EQ(1, bits);
2188 flag = flags[i];
2189
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002190 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2191 ASSERT_NE(ENOSYS, errno) {
2192 TH_LOG("Kernel does not support seccomp syscall!");
2193 }
2194 EXPECT_EQ(-1, ret);
2195 EXPECT_EQ(EFAULT, errno) {
2196 TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
2197 flag);
2198 }
2199
2200 all_flags |= flag;
2201 }
2202
Kees Cook4ee07762019-04-24 09:32:55 -07002203 /*
2204 * Test detection of all known-good filter flags combined. But
2205 * for the exclusive flags we need to mask them out and try them
2206 * individually for the "all flags" testing.
2207 */
2208 exclusive_mask = 0;
2209 for (i = 0; i < ARRAY_SIZE(exclusive); i++)
2210 exclusive_mask |= exclusive[i];
2211 for (i = 0; i < ARRAY_SIZE(exclusive); i++) {
2212 flag = all_flags & ~exclusive_mask;
2213 flag |= exclusive[i];
2214
2215 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2216 EXPECT_EQ(-1, ret);
2217 EXPECT_EQ(EFAULT, errno) {
2218 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
2219 flag);
2220 }
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002221 }
2222
Kees Cook4ee07762019-04-24 09:32:55 -07002223 /* Test detection of an unknown filter flags, without exclusives. */
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002224 flag = -1;
Kees Cook4ee07762019-04-24 09:32:55 -07002225 flag &= ~exclusive_mask;
Tyler Hicks2b7ea5b2017-08-11 04:33:55 +00002226 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2227 EXPECT_EQ(-1, ret);
2228 EXPECT_EQ(EINVAL, errno) {
2229 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
2230 flag);
2231 }
2232
2233 /*
2234 * Test detection of an unknown filter flag that may simply need to be
2235 * added to this test
2236 */
2237 flag = flags[ARRAY_SIZE(flags) - 1] << 1;
2238 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2239 EXPECT_EQ(-1, ret);
2240 EXPECT_EQ(EINVAL, errno) {
2241 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?",
2242 flag);
2243 }
2244}
2245
Kees Cookc99ee512015-06-16 10:54:14 -07002246TEST(TSYNC_first)
2247{
2248 struct sock_filter filter[] = {
2249 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2250 };
2251 struct sock_fprog prog = {
2252 .len = (unsigned short)ARRAY_SIZE(filter),
2253 .filter = filter,
2254 };
2255 long ret;
2256
2257 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2258 ASSERT_EQ(0, ret) {
2259 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2260 }
2261
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002262 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002263 &prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002264 ASSERT_NE(ENOSYS, errno) {
2265 TH_LOG("Kernel does not support seccomp syscall!");
2266 }
Kees Cookc99ee512015-06-16 10:54:14 -07002267 EXPECT_EQ(0, ret) {
2268 TH_LOG("Could not install initial filter with TSYNC!");
2269 }
2270}
2271
2272#define TSYNC_SIBLINGS 2
2273struct tsync_sibling {
2274 pthread_t tid;
2275 pid_t system_tid;
2276 sem_t *started;
2277 pthread_cond_t *cond;
2278 pthread_mutex_t *mutex;
2279 int diverge;
2280 int num_waits;
2281 struct sock_fprog *prog;
2282 struct __test_metadata *metadata;
2283};
2284
Kees Cook93bd70e2017-03-20 16:41:35 -07002285/*
2286 * To avoid joining joined threads (which is not allowed by Bionic),
2287 * make sure we both successfully join and clear the tid to skip a
2288 * later join attempt during fixture teardown. Any remaining threads
2289 * will be directly killed during teardown.
2290 */
2291#define PTHREAD_JOIN(tid, status) \
2292 do { \
2293 int _rc = pthread_join(tid, status); \
2294 if (_rc) { \
2295 TH_LOG("pthread_join of tid %u failed: %d\n", \
2296 (unsigned int)tid, _rc); \
2297 } else { \
2298 tid = 0; \
2299 } \
2300 } while (0)
2301
Kees Cookc99ee512015-06-16 10:54:14 -07002302FIXTURE_DATA(TSYNC) {
2303 struct sock_fprog root_prog, apply_prog;
2304 struct tsync_sibling sibling[TSYNC_SIBLINGS];
2305 sem_t started;
2306 pthread_cond_t cond;
2307 pthread_mutex_t mutex;
2308 int sibling_count;
2309};
2310
2311FIXTURE_SETUP(TSYNC)
2312{
2313 struct sock_filter root_filter[] = {
2314 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2315 };
2316 struct sock_filter apply_filter[] = {
2317 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2318 offsetof(struct seccomp_data, nr)),
2319 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
2320 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2321 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2322 };
2323
2324 memset(&self->root_prog, 0, sizeof(self->root_prog));
2325 memset(&self->apply_prog, 0, sizeof(self->apply_prog));
2326 memset(&self->sibling, 0, sizeof(self->sibling));
2327 self->root_prog.filter = malloc(sizeof(root_filter));
2328 ASSERT_NE(NULL, self->root_prog.filter);
2329 memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
2330 self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
2331
2332 self->apply_prog.filter = malloc(sizeof(apply_filter));
2333 ASSERT_NE(NULL, self->apply_prog.filter);
2334 memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
2335 self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
2336
2337 self->sibling_count = 0;
2338 pthread_mutex_init(&self->mutex, NULL);
2339 pthread_cond_init(&self->cond, NULL);
2340 sem_init(&self->started, 0, 0);
2341 self->sibling[0].tid = 0;
2342 self->sibling[0].cond = &self->cond;
2343 self->sibling[0].started = &self->started;
2344 self->sibling[0].mutex = &self->mutex;
2345 self->sibling[0].diverge = 0;
2346 self->sibling[0].num_waits = 1;
2347 self->sibling[0].prog = &self->root_prog;
2348 self->sibling[0].metadata = _metadata;
2349 self->sibling[1].tid = 0;
2350 self->sibling[1].cond = &self->cond;
2351 self->sibling[1].started = &self->started;
2352 self->sibling[1].mutex = &self->mutex;
2353 self->sibling[1].diverge = 0;
2354 self->sibling[1].prog = &self->root_prog;
2355 self->sibling[1].num_waits = 1;
2356 self->sibling[1].metadata = _metadata;
2357}
2358
2359FIXTURE_TEARDOWN(TSYNC)
2360{
2361 int sib = 0;
2362
2363 if (self->root_prog.filter)
2364 free(self->root_prog.filter);
2365 if (self->apply_prog.filter)
2366 free(self->apply_prog.filter);
2367
2368 for ( ; sib < self->sibling_count; ++sib) {
2369 struct tsync_sibling *s = &self->sibling[sib];
Kees Cookc99ee512015-06-16 10:54:14 -07002370
2371 if (!s->tid)
2372 continue;
Kees Cook93bd70e2017-03-20 16:41:35 -07002373 /*
2374 * If a thread is still running, it may be stuck, so hit
2375 * it over the head really hard.
2376 */
2377 pthread_kill(s->tid, 9);
Kees Cookc99ee512015-06-16 10:54:14 -07002378 }
2379 pthread_mutex_destroy(&self->mutex);
2380 pthread_cond_destroy(&self->cond);
2381 sem_destroy(&self->started);
2382}
2383
2384void *tsync_sibling(void *data)
2385{
2386 long ret = 0;
2387 struct tsync_sibling *me = data;
2388
2389 me->system_tid = syscall(__NR_gettid);
2390
2391 pthread_mutex_lock(me->mutex);
2392 if (me->diverge) {
2393 /* Just re-apply the root prog to fork the tree */
2394 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
2395 me->prog, 0, 0);
2396 }
2397 sem_post(me->started);
2398 /* Return outside of started so parent notices failures. */
2399 if (ret) {
2400 pthread_mutex_unlock(me->mutex);
2401 return (void *)SIBLING_EXIT_FAILURE;
2402 }
2403 do {
2404 pthread_cond_wait(me->cond, me->mutex);
2405 me->num_waits = me->num_waits - 1;
2406 } while (me->num_waits);
2407 pthread_mutex_unlock(me->mutex);
2408
2409 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
2410 if (!ret)
2411 return (void *)SIBLING_EXIT_NEWPRIVS;
2412 read(0, NULL, 0);
2413 return (void *)SIBLING_EXIT_UNKILLED;
2414}
2415
2416void tsync_start_sibling(struct tsync_sibling *sibling)
2417{
2418 pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
2419}
2420
2421TEST_F(TSYNC, siblings_fail_prctl)
2422{
2423 long ret;
2424 void *status;
2425 struct sock_filter filter[] = {
2426 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2427 offsetof(struct seccomp_data, nr)),
2428 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
2429 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
2430 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2431 };
2432 struct sock_fprog prog = {
2433 .len = (unsigned short)ARRAY_SIZE(filter),
2434 .filter = filter,
2435 };
2436
2437 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2438 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2439 }
2440
2441 /* Check prctl failure detection by requesting sib 0 diverge. */
2442 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002443 ASSERT_NE(ENOSYS, errno) {
2444 TH_LOG("Kernel does not support seccomp syscall!");
2445 }
Kees Cookc99ee512015-06-16 10:54:14 -07002446 ASSERT_EQ(0, ret) {
2447 TH_LOG("setting filter failed");
2448 }
2449
2450 self->sibling[0].diverge = 1;
2451 tsync_start_sibling(&self->sibling[0]);
2452 tsync_start_sibling(&self->sibling[1]);
2453
2454 while (self->sibling_count < TSYNC_SIBLINGS) {
2455 sem_wait(&self->started);
2456 self->sibling_count++;
2457 }
2458
2459 /* Signal the threads to clean up*/
2460 pthread_mutex_lock(&self->mutex);
2461 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2462 TH_LOG("cond broadcast non-zero");
2463 }
2464 pthread_mutex_unlock(&self->mutex);
2465
2466 /* Ensure diverging sibling failed to call prctl. */
Kees Cook93bd70e2017-03-20 16:41:35 -07002467 PTHREAD_JOIN(self->sibling[0].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002468 EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
Kees Cook93bd70e2017-03-20 16:41:35 -07002469 PTHREAD_JOIN(self->sibling[1].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002470 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2471}
2472
2473TEST_F(TSYNC, two_siblings_with_ancestor)
2474{
2475 long ret;
2476 void *status;
2477
2478 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2479 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2480 }
2481
2482 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002483 ASSERT_NE(ENOSYS, errno) {
2484 TH_LOG("Kernel does not support seccomp syscall!");
2485 }
Kees Cookc99ee512015-06-16 10:54:14 -07002486 ASSERT_EQ(0, ret) {
2487 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2488 }
2489 tsync_start_sibling(&self->sibling[0]);
2490 tsync_start_sibling(&self->sibling[1]);
2491
2492 while (self->sibling_count < TSYNC_SIBLINGS) {
2493 sem_wait(&self->started);
2494 self->sibling_count++;
2495 }
2496
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002497 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002498 &self->apply_prog);
2499 ASSERT_EQ(0, ret) {
2500 TH_LOG("Could install filter on all threads!");
2501 }
2502 /* Tell the siblings to test the policy */
2503 pthread_mutex_lock(&self->mutex);
2504 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2505 TH_LOG("cond broadcast non-zero");
2506 }
2507 pthread_mutex_unlock(&self->mutex);
2508 /* Ensure they are both killed and don't exit cleanly. */
Kees Cook93bd70e2017-03-20 16:41:35 -07002509 PTHREAD_JOIN(self->sibling[0].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002510 EXPECT_EQ(0x0, (long)status);
Kees Cook93bd70e2017-03-20 16:41:35 -07002511 PTHREAD_JOIN(self->sibling[1].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002512 EXPECT_EQ(0x0, (long)status);
2513}
2514
2515TEST_F(TSYNC, two_sibling_want_nnp)
2516{
2517 void *status;
2518
2519 /* start siblings before any prctl() operations */
2520 tsync_start_sibling(&self->sibling[0]);
2521 tsync_start_sibling(&self->sibling[1]);
2522 while (self->sibling_count < TSYNC_SIBLINGS) {
2523 sem_wait(&self->started);
2524 self->sibling_count++;
2525 }
2526
2527 /* Tell the siblings to test no policy */
2528 pthread_mutex_lock(&self->mutex);
2529 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2530 TH_LOG("cond broadcast non-zero");
2531 }
2532 pthread_mutex_unlock(&self->mutex);
2533
2534 /* Ensure they are both upset about lacking nnp. */
Kees Cook93bd70e2017-03-20 16:41:35 -07002535 PTHREAD_JOIN(self->sibling[0].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002536 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
Kees Cook93bd70e2017-03-20 16:41:35 -07002537 PTHREAD_JOIN(self->sibling[1].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002538 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2539}
2540
2541TEST_F(TSYNC, two_siblings_with_no_filter)
2542{
2543 long ret;
2544 void *status;
2545
2546 /* start siblings before any prctl() operations */
2547 tsync_start_sibling(&self->sibling[0]);
2548 tsync_start_sibling(&self->sibling[1]);
2549 while (self->sibling_count < TSYNC_SIBLINGS) {
2550 sem_wait(&self->started);
2551 self->sibling_count++;
2552 }
2553
2554 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2555 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2556 }
2557
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002558 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002559 &self->apply_prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002560 ASSERT_NE(ENOSYS, errno) {
2561 TH_LOG("Kernel does not support seccomp syscall!");
2562 }
Kees Cookc99ee512015-06-16 10:54:14 -07002563 ASSERT_EQ(0, ret) {
2564 TH_LOG("Could install filter on all threads!");
2565 }
2566
2567 /* Tell the siblings to test the policy */
2568 pthread_mutex_lock(&self->mutex);
2569 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2570 TH_LOG("cond broadcast non-zero");
2571 }
2572 pthread_mutex_unlock(&self->mutex);
2573
2574 /* Ensure they are both killed and don't exit cleanly. */
Kees Cook93bd70e2017-03-20 16:41:35 -07002575 PTHREAD_JOIN(self->sibling[0].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002576 EXPECT_EQ(0x0, (long)status);
Kees Cook93bd70e2017-03-20 16:41:35 -07002577 PTHREAD_JOIN(self->sibling[1].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002578 EXPECT_EQ(0x0, (long)status);
2579}
2580
2581TEST_F(TSYNC, two_siblings_with_one_divergence)
2582{
2583 long ret;
2584 void *status;
2585
2586 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2587 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2588 }
2589
2590 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002591 ASSERT_NE(ENOSYS, errno) {
2592 TH_LOG("Kernel does not support seccomp syscall!");
2593 }
Kees Cookc99ee512015-06-16 10:54:14 -07002594 ASSERT_EQ(0, ret) {
2595 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2596 }
2597 self->sibling[0].diverge = 1;
2598 tsync_start_sibling(&self->sibling[0]);
2599 tsync_start_sibling(&self->sibling[1]);
2600
2601 while (self->sibling_count < TSYNC_SIBLINGS) {
2602 sem_wait(&self->started);
2603 self->sibling_count++;
2604 }
2605
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002606 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002607 &self->apply_prog);
2608 ASSERT_EQ(self->sibling[0].system_tid, ret) {
2609 TH_LOG("Did not fail on diverged sibling.");
2610 }
2611
2612 /* Wake the threads */
2613 pthread_mutex_lock(&self->mutex);
2614 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2615 TH_LOG("cond broadcast non-zero");
2616 }
2617 pthread_mutex_unlock(&self->mutex);
2618
2619 /* Ensure they are both unkilled. */
Kees Cook93bd70e2017-03-20 16:41:35 -07002620 PTHREAD_JOIN(self->sibling[0].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002621 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
Kees Cook93bd70e2017-03-20 16:41:35 -07002622 PTHREAD_JOIN(self->sibling[1].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002623 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2624}
2625
2626TEST_F(TSYNC, two_siblings_not_under_filter)
2627{
2628 long ret, sib;
2629 void *status;
Kees Cooked492c22019-01-27 01:43:57 -08002630 struct timespec delay = { .tv_nsec = 100000000 };
Kees Cookc99ee512015-06-16 10:54:14 -07002631
2632 ASSERT_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 /*
2637 * Sibling 0 will have its own seccomp policy
2638 * and Sibling 1 will not be under seccomp at
2639 * all. Sibling 1 will enter seccomp and 0
2640 * will cause failure.
2641 */
2642 self->sibling[0].diverge = 1;
2643 tsync_start_sibling(&self->sibling[0]);
2644 tsync_start_sibling(&self->sibling[1]);
2645
2646 while (self->sibling_count < TSYNC_SIBLINGS) {
2647 sem_wait(&self->started);
2648 self->sibling_count++;
2649 }
2650
2651 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
Kees Cookb623c4d2015-08-21 11:22:35 -07002652 ASSERT_NE(ENOSYS, errno) {
2653 TH_LOG("Kernel does not support seccomp syscall!");
2654 }
Kees Cookc99ee512015-06-16 10:54:14 -07002655 ASSERT_EQ(0, ret) {
2656 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2657 }
2658
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002659 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002660 &self->apply_prog);
2661 ASSERT_EQ(ret, self->sibling[0].system_tid) {
2662 TH_LOG("Did not fail on diverged sibling.");
2663 }
2664 sib = 1;
2665 if (ret == self->sibling[0].system_tid)
2666 sib = 0;
2667
2668 pthread_mutex_lock(&self->mutex);
2669
2670 /* Increment the other siblings num_waits so we can clean up
2671 * the one we just saw.
2672 */
2673 self->sibling[!sib].num_waits += 1;
2674
2675 /* Signal the thread to clean up*/
2676 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2677 TH_LOG("cond broadcast non-zero");
2678 }
2679 pthread_mutex_unlock(&self->mutex);
Kees Cook93bd70e2017-03-20 16:41:35 -07002680 PTHREAD_JOIN(self->sibling[sib].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002681 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2682 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2683 while (!kill(self->sibling[sib].system_tid, 0))
Kees Cooked492c22019-01-27 01:43:57 -08002684 nanosleep(&delay, NULL);
Kees Cookc99ee512015-06-16 10:54:14 -07002685 /* Switch to the remaining sibling */
2686 sib = !sib;
2687
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002688 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002689 &self->apply_prog);
2690 ASSERT_EQ(0, ret) {
2691 TH_LOG("Expected the remaining sibling to sync");
2692 };
2693
2694 pthread_mutex_lock(&self->mutex);
2695
2696 /* If remaining sibling didn't have a chance to wake up during
2697 * the first broadcast, manually reduce the num_waits now.
2698 */
2699 if (self->sibling[sib].num_waits > 1)
2700 self->sibling[sib].num_waits = 1;
2701 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2702 TH_LOG("cond broadcast non-zero");
2703 }
2704 pthread_mutex_unlock(&self->mutex);
Kees Cook93bd70e2017-03-20 16:41:35 -07002705 PTHREAD_JOIN(self->sibling[sib].tid, &status);
Kees Cookc99ee512015-06-16 10:54:14 -07002706 EXPECT_EQ(0, (long)status);
2707 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2708 while (!kill(self->sibling[sib].system_tid, 0))
Kees Cooked492c22019-01-27 01:43:57 -08002709 nanosleep(&delay, NULL);
Kees Cookc99ee512015-06-16 10:54:14 -07002710
Mickaël Salaün6c045d02016-03-29 20:46:07 +02002711 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
Kees Cookc99ee512015-06-16 10:54:14 -07002712 &self->apply_prog);
2713 ASSERT_EQ(0, ret); /* just us chickens */
2714}
2715
2716/* Make sure restarted syscalls are seen directly as "restart_syscall". */
2717TEST(syscall_restart)
2718{
2719 long ret;
2720 unsigned long msg;
2721 pid_t child_pid;
2722 int pipefd[2];
2723 int status;
2724 siginfo_t info = { };
2725 struct sock_filter filter[] = {
2726 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2727 offsetof(struct seccomp_data, nr)),
2728
2729#ifdef __NR_sigreturn
2730 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0),
2731#endif
2732 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
2733 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
2734 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
Kees Cook256d0af2015-10-06 12:30:25 -07002735 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0),
Kees Cookc99ee512015-06-16 10:54:14 -07002736 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2737
2738 /* Allow __NR_write for easy logging. */
2739 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2740 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2741 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
Kees Cook256d0af2015-10-06 12:30:25 -07002742 /* The nanosleep jump target. */
2743 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2744 /* The restart_syscall jump target. */
2745 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
Kees Cookc99ee512015-06-16 10:54:14 -07002746 };
2747 struct sock_fprog prog = {
2748 .len = (unsigned short)ARRAY_SIZE(filter),
2749 .filter = filter,
2750 };
Kees Cook256d0af2015-10-06 12:30:25 -07002751#if defined(__arm__)
2752 struct utsname utsbuf;
2753#endif
Kees Cookc99ee512015-06-16 10:54:14 -07002754
2755 ASSERT_EQ(0, pipe(pipefd));
2756
2757 child_pid = fork();
2758 ASSERT_LE(0, child_pid);
2759 if (child_pid == 0) {
2760 /* Child uses EXPECT not ASSERT to deliver status correctly. */
2761 char buf = ' ';
Kees Cook256d0af2015-10-06 12:30:25 -07002762 struct timespec timeout = { };
Kees Cookc99ee512015-06-16 10:54:14 -07002763
2764 /* Attach parent as tracer and stop. */
2765 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2766 EXPECT_EQ(0, raise(SIGSTOP));
2767
2768 EXPECT_EQ(0, close(pipefd[1]));
2769
2770 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2771 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2772 }
2773
2774 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2775 EXPECT_EQ(0, ret) {
2776 TH_LOG("Failed to install filter!");
2777 }
2778
2779 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2780 TH_LOG("Failed to read() sync from parent");
2781 }
2782 EXPECT_EQ('.', buf) {
2783 TH_LOG("Failed to get sync data from read()");
2784 }
2785
Kees Cook256d0af2015-10-06 12:30:25 -07002786 /* Start nanosleep to be interrupted. */
2787 timeout.tv_sec = 1;
Kees Cookc99ee512015-06-16 10:54:14 -07002788 errno = 0;
Kees Cook256d0af2015-10-06 12:30:25 -07002789 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2790 TH_LOG("Call to nanosleep() failed (errno %d)", errno);
Kees Cookc99ee512015-06-16 10:54:14 -07002791 }
2792
2793 /* Read final sync from parent. */
2794 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2795 TH_LOG("Failed final read() from parent");
2796 }
2797 EXPECT_EQ('!', buf) {
2798 TH_LOG("Failed to get final data from read()");
2799 }
2800
2801 /* Directly report the status of our test harness results. */
2802 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2803 : EXIT_FAILURE);
2804 }
2805 EXPECT_EQ(0, close(pipefd[0]));
2806
2807 /* Attach to child, setup options, and release. */
2808 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2809 ASSERT_EQ(true, WIFSTOPPED(status));
2810 ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2811 PTRACE_O_TRACESECCOMP));
2812 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2813 ASSERT_EQ(1, write(pipefd[1], ".", 1));
2814
Kees Cook256d0af2015-10-06 12:30:25 -07002815 /* Wait for nanosleep() to start. */
Kees Cookc99ee512015-06-16 10:54:14 -07002816 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2817 ASSERT_EQ(true, WIFSTOPPED(status));
2818 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2819 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2820 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2821 ASSERT_EQ(0x100, msg);
Kees Cook256d0af2015-10-06 12:30:25 -07002822 EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
Kees Cookc99ee512015-06-16 10:54:14 -07002823
2824 /* Might as well check siginfo for sanity while we're here. */
2825 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2826 ASSERT_EQ(SIGTRAP, info.si_signo);
2827 ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2828 EXPECT_EQ(0, info.si_errno);
2829 EXPECT_EQ(getuid(), info.si_uid);
2830 /* Verify signal delivery came from child (seccomp-triggered). */
2831 EXPECT_EQ(child_pid, info.si_pid);
2832
Kees Cook256d0af2015-10-06 12:30:25 -07002833 /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
Kees Cookc99ee512015-06-16 10:54:14 -07002834 ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2835 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2836 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2837 ASSERT_EQ(true, WIFSTOPPED(status));
2838 ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
Kees Cookc99ee512015-06-16 10:54:14 -07002839 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
Kees Cook2bd61ab2018-12-06 15:50:38 -08002840 /*
2841 * There is no siginfo on SIGSTOP any more, so we can't verify
2842 * signal delivery came from parent now (getpid() == info.si_pid).
2843 * https://lkml.kernel.org/r/CAGXu5jJaZAOzP1qFz66tYrtbuywqb+UN2SOA1VLHpCCOiYvYeg@mail.gmail.com
2844 * At least verify the SIGSTOP via PTRACE_GETSIGINFO.
2845 */
2846 EXPECT_EQ(SIGSTOP, info.si_signo);
Kees Cookc99ee512015-06-16 10:54:14 -07002847
Kees Cook256d0af2015-10-06 12:30:25 -07002848 /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
Kees Cookc99ee512015-06-16 10:54:14 -07002849 ASSERT_EQ(0, kill(child_pid, SIGCONT));
2850 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2851 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2852 ASSERT_EQ(true, WIFSTOPPED(status));
2853 ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2854 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2855
2856 /* Wait for restart_syscall() to start. */
2857 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2858 ASSERT_EQ(true, WIFSTOPPED(status));
2859 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2860 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2861 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
Kees Cook256d0af2015-10-06 12:30:25 -07002862
Kees Cookc99ee512015-06-16 10:54:14 -07002863 ASSERT_EQ(0x200, msg);
2864 ret = get_syscall(_metadata, child_pid);
2865#if defined(__arm__)
Kees Cook256d0af2015-10-06 12:30:25 -07002866 /*
2867 * FIXME:
2868 * - native ARM registers do NOT expose true syscall.
2869 * - compat ARM registers on ARM64 DO expose true syscall.
2870 */
2871 ASSERT_EQ(0, uname(&utsbuf));
2872 if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2873 EXPECT_EQ(__NR_nanosleep, ret);
2874 } else
Kees Cookc99ee512015-06-16 10:54:14 -07002875#endif
Kees Cook256d0af2015-10-06 12:30:25 -07002876 {
2877 EXPECT_EQ(__NR_restart_syscall, ret);
2878 }
Kees Cookc99ee512015-06-16 10:54:14 -07002879
Kees Cook256d0af2015-10-06 12:30:25 -07002880 /* Write again to end test. */
Kees Cookc99ee512015-06-16 10:54:14 -07002881 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2882 ASSERT_EQ(1, write(pipefd[1], "!", 1));
2883 EXPECT_EQ(0, close(pipefd[1]));
2884
2885 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2886 if (WIFSIGNALED(status) || WEXITSTATUS(status))
2887 _metadata->passed = 0;
2888}
2889
Tyler Hickse66a3992017-08-11 04:33:56 +00002890TEST_SIGNAL(filter_flag_log, SIGSYS)
2891{
2892 struct sock_filter allow_filter[] = {
2893 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2894 };
2895 struct sock_filter kill_filter[] = {
2896 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2897 offsetof(struct seccomp_data, nr)),
2898 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
2899 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2900 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2901 };
2902 struct sock_fprog allow_prog = {
2903 .len = (unsigned short)ARRAY_SIZE(allow_filter),
2904 .filter = allow_filter,
2905 };
2906 struct sock_fprog kill_prog = {
2907 .len = (unsigned short)ARRAY_SIZE(kill_filter),
2908 .filter = kill_filter,
2909 };
2910 long ret;
2911 pid_t parent = getppid();
2912
2913 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2914 ASSERT_EQ(0, ret);
2915
2916 /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
2917 ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
2918 &allow_prog);
2919 ASSERT_NE(ENOSYS, errno) {
2920 TH_LOG("Kernel does not support seccomp syscall!");
2921 }
2922 EXPECT_NE(0, ret) {
2923 TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
2924 }
2925 EXPECT_EQ(EINVAL, errno) {
2926 TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
2927 }
2928
2929 /* Verify that a simple, permissive filter can be added with no flags */
2930 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
2931 EXPECT_EQ(0, ret);
2932
2933 /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
2934 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2935 &allow_prog);
2936 ASSERT_NE(EINVAL, errno) {
2937 TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
2938 }
2939 EXPECT_EQ(0, ret);
2940
2941 /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
2942 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2943 &kill_prog);
2944 EXPECT_EQ(0, ret);
2945
2946 EXPECT_EQ(parent, syscall(__NR_getppid));
2947 /* getpid() should never return. */
2948 EXPECT_EQ(0, syscall(__NR_getpid));
2949}
2950
Tyler Hicksd612b1f2017-08-11 04:33:53 +00002951TEST(get_action_avail)
2952{
Kees Cookfd768752017-08-11 12:53:18 -07002953 __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
Tyler Hicksd612b1f2017-08-11 04:33:53 +00002954 SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
Tyler Hicks59f5cf42017-08-11 04:33:57 +00002955 SECCOMP_RET_LOG, SECCOMP_RET_ALLOW };
Tyler Hicksd612b1f2017-08-11 04:33:53 +00002956 __u32 unknown_action = 0x10000000U;
2957 int i;
2958 long ret;
2959
2960 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
2961 ASSERT_NE(ENOSYS, errno) {
2962 TH_LOG("Kernel does not support seccomp syscall!");
2963 }
2964 ASSERT_NE(EINVAL, errno) {
2965 TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
2966 }
2967 EXPECT_EQ(ret, 0);
2968
2969 for (i = 0; i < ARRAY_SIZE(actions); i++) {
2970 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
2971 EXPECT_EQ(ret, 0) {
2972 TH_LOG("Expected action (0x%X) not available!",
2973 actions[i]);
2974 }
2975 }
2976
2977 /* Check that an unknown action is handled properly (EOPNOTSUPP) */
2978 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
2979 EXPECT_EQ(ret, -1);
2980 EXPECT_EQ(errno, EOPNOTSUPP);
2981}
2982
Tycho Andersend057dc42018-02-20 19:47:47 -07002983TEST(get_metadata)
2984{
2985 pid_t pid;
2986 int pipefd[2];
2987 char buf;
2988 struct seccomp_metadata md;
Kees Cook6c3b6d52018-03-15 09:59:16 -07002989 long ret;
Tycho Andersend057dc42018-02-20 19:47:47 -07002990
Tycho Andersen3aa415dd2019-01-18 17:12:15 -07002991 /* Only real root can get metadata. */
2992 if (geteuid()) {
2993 XFAIL(return, "get_metadata requires real root");
2994 return;
2995 }
2996
Tycho Andersend057dc42018-02-20 19:47:47 -07002997 ASSERT_EQ(0, pipe(pipefd));
2998
2999 pid = fork();
3000 ASSERT_GE(pid, 0);
3001 if (pid == 0) {
3002 struct sock_filter filter[] = {
3003 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3004 };
3005 struct sock_fprog prog = {
3006 .len = (unsigned short)ARRAY_SIZE(filter),
3007 .filter = filter,
3008 };
3009
3010 /* one with log, one without */
Tycho Andersenfb024a02019-01-18 17:12:12 -07003011 EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
Tycho Andersend057dc42018-02-20 19:47:47 -07003012 SECCOMP_FILTER_FLAG_LOG, &prog));
Tycho Andersenfb024a02019-01-18 17:12:12 -07003013 EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));
Tycho Andersend057dc42018-02-20 19:47:47 -07003014
Tycho Andersenfb024a02019-01-18 17:12:12 -07003015 EXPECT_EQ(0, close(pipefd[0]));
Tycho Andersend057dc42018-02-20 19:47:47 -07003016 ASSERT_EQ(1, write(pipefd[1], "1", 1));
3017 ASSERT_EQ(0, close(pipefd[1]));
3018
3019 while (1)
3020 sleep(100);
3021 }
3022
3023 ASSERT_EQ(0, close(pipefd[1]));
3024 ASSERT_EQ(1, read(pipefd[0], &buf, 1));
3025
3026 ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
3027 ASSERT_EQ(pid, waitpid(pid, NULL, 0));
3028
Kees Cook6c3b6d52018-03-15 09:59:16 -07003029 /* Past here must not use ASSERT or child process is never killed. */
3030
Tycho Andersend057dc42018-02-20 19:47:47 -07003031 md.filter_off = 0;
Kees Cook6c3b6d52018-03-15 09:59:16 -07003032 errno = 0;
3033 ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
3034 EXPECT_EQ(sizeof(md), ret) {
3035 if (errno == EINVAL)
3036 XFAIL(goto skip, "Kernel does not support PTRACE_SECCOMP_GET_METADATA (missing CONFIG_CHECKPOINT_RESTORE?)");
3037 }
3038
Tycho Andersend057dc42018-02-20 19:47:47 -07003039 EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
3040 EXPECT_EQ(md.filter_off, 0);
3041
3042 md.filter_off = 1;
Kees Cook6c3b6d52018-03-15 09:59:16 -07003043 ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
3044 EXPECT_EQ(sizeof(md), ret);
Tycho Andersend057dc42018-02-20 19:47:47 -07003045 EXPECT_EQ(md.flags, 0);
3046 EXPECT_EQ(md.filter_off, 1);
3047
Kees Cook6c3b6d52018-03-15 09:59:16 -07003048skip:
Tycho Andersend057dc42018-02-20 19:47:47 -07003049 ASSERT_EQ(0, kill(pid, SIGKILL));
3050}
3051
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003052static int user_trap_syscall(int nr, unsigned int flags)
3053{
3054 struct sock_filter filter[] = {
3055 BPF_STMT(BPF_LD+BPF_W+BPF_ABS,
3056 offsetof(struct seccomp_data, nr)),
3057 BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, nr, 0, 1),
3058 BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_USER_NOTIF),
3059 BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_ALLOW),
3060 };
3061
3062 struct sock_fprog prog = {
3063 .len = (unsigned short)ARRAY_SIZE(filter),
3064 .filter = filter,
3065 };
3066
3067 return seccomp(SECCOMP_SET_MODE_FILTER, flags, &prog);
3068}
3069
3070#define USER_NOTIF_MAGIC 116983961184613L
3071TEST(user_notification_basic)
3072{
3073 pid_t pid;
3074 long ret;
3075 int status, listener;
3076 struct seccomp_notif req = {};
3077 struct seccomp_notif_resp resp = {};
3078 struct pollfd pollfd;
3079
3080 struct sock_filter filter[] = {
3081 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3082 };
3083 struct sock_fprog prog = {
3084 .len = (unsigned short)ARRAY_SIZE(filter),
3085 .filter = filter,
3086 };
3087
Tycho Andersenc7140702019-01-18 17:12:16 -07003088 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3089 ASSERT_EQ(0, ret) {
3090 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3091 }
3092
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003093 pid = fork();
3094 ASSERT_GE(pid, 0);
3095
3096 /* Check that we get -ENOSYS with no listener attached */
3097 if (pid == 0) {
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003098 if (user_trap_syscall(__NR_getppid, 0) < 0)
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003099 exit(1);
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003100 ret = syscall(__NR_getppid);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003101 exit(ret >= 0 || errno != ENOSYS);
3102 }
3103
3104 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3105 EXPECT_EQ(true, WIFEXITED(status));
3106 EXPECT_EQ(0, WEXITSTATUS(status));
3107
Tycho Andersen0b54b442019-01-18 17:12:13 -07003108 /* Add some no-op filters for grins. */
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003109 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3110 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3111 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3112 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3113
3114 /* Check that the basic notification machinery works */
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003115 listener = user_trap_syscall(__NR_getppid,
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003116 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Kees Cook3d244c12019-01-16 16:35:25 -08003117 ASSERT_GE(listener, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003118
3119 /* Installing a second listener in the chain should EBUSY */
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003120 EXPECT_EQ(user_trap_syscall(__NR_getppid,
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003121 SECCOMP_FILTER_FLAG_NEW_LISTENER),
3122 -1);
3123 EXPECT_EQ(errno, EBUSY);
3124
3125 pid = fork();
3126 ASSERT_GE(pid, 0);
3127
3128 if (pid == 0) {
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003129 ret = syscall(__NR_getppid);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003130 exit(ret != USER_NOTIF_MAGIC);
3131 }
3132
3133 pollfd.fd = listener;
3134 pollfd.events = POLLIN | POLLOUT;
3135
3136 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3137 EXPECT_EQ(pollfd.revents, POLLIN);
3138
3139 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3140
3141 pollfd.fd = listener;
3142 pollfd.events = POLLIN | POLLOUT;
3143
3144 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3145 EXPECT_EQ(pollfd.revents, POLLOUT);
3146
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003147 EXPECT_EQ(req.data.nr, __NR_getppid);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003148
3149 resp.id = req.id;
3150 resp.error = 0;
3151 resp.val = USER_NOTIF_MAGIC;
3152
3153 /* check that we make sure flags == 0 */
3154 resp.flags = 1;
3155 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3156 EXPECT_EQ(errno, EINVAL);
3157
3158 resp.flags = 0;
3159 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3160
3161 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3162 EXPECT_EQ(true, WIFEXITED(status));
3163 EXPECT_EQ(0, WEXITSTATUS(status));
3164}
3165
3166TEST(user_notification_kill_in_middle)
3167{
3168 pid_t pid;
3169 long ret;
3170 int listener;
3171 struct seccomp_notif req = {};
3172 struct seccomp_notif_resp resp = {};
3173
Tycho Andersenc7140702019-01-18 17:12:16 -07003174 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3175 ASSERT_EQ(0, ret) {
3176 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3177 }
3178
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003179 listener = user_trap_syscall(__NR_getppid,
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003180 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Kees Cook3d244c12019-01-16 16:35:25 -08003181 ASSERT_GE(listener, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003182
3183 /*
3184 * Check that nothing bad happens when we kill the task in the middle
3185 * of a syscall.
3186 */
3187 pid = fork();
3188 ASSERT_GE(pid, 0);
3189
3190 if (pid == 0) {
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003191 ret = syscall(__NR_getppid);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003192 exit(ret != USER_NOTIF_MAGIC);
3193 }
3194
3195 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3196 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), 0);
3197
3198 EXPECT_EQ(kill(pid, SIGKILL), 0);
3199 EXPECT_EQ(waitpid(pid, NULL, 0), pid);
3200
3201 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), -1);
3202
3203 resp.id = req.id;
3204 ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp);
3205 EXPECT_EQ(ret, -1);
3206 EXPECT_EQ(errno, ENOENT);
3207}
3208
3209static int handled = -1;
3210
3211static void signal_handler(int signal)
3212{
3213 if (write(handled, "c", 1) != 1)
3214 perror("write from signal");
3215}
3216
3217TEST(user_notification_signal)
3218{
3219 pid_t pid;
3220 long ret;
3221 int status, listener, sk_pair[2];
3222 struct seccomp_notif req = {};
3223 struct seccomp_notif_resp resp = {};
3224 char c;
3225
Tycho Andersenc7140702019-01-18 17:12:16 -07003226 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3227 ASSERT_EQ(0, ret) {
3228 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3229 }
3230
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003231 ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);
3232
3233 listener = user_trap_syscall(__NR_gettid,
3234 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Kees Cook3d244c12019-01-16 16:35:25 -08003235 ASSERT_GE(listener, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003236
3237 pid = fork();
3238 ASSERT_GE(pid, 0);
3239
3240 if (pid == 0) {
3241 close(sk_pair[0]);
3242 handled = sk_pair[1];
3243 if (signal(SIGUSR1, signal_handler) == SIG_ERR) {
3244 perror("signal");
3245 exit(1);
3246 }
3247 /*
3248 * ERESTARTSYS behavior is a bit hard to test, because we need
3249 * to rely on a signal that has not yet been handled. Let's at
3250 * least check that the error code gets propagated through, and
3251 * hope that it doesn't break when there is actually a signal :)
3252 */
3253 ret = syscall(__NR_gettid);
3254 exit(!(ret == -1 && errno == 512));
3255 }
3256
3257 close(sk_pair[1]);
3258
3259 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3260
3261 EXPECT_EQ(kill(pid, SIGUSR1), 0);
3262
3263 /*
3264 * Make sure the signal really is delivered, which means we're not
3265 * stuck in the user notification code any more and the notification
3266 * should be dead.
3267 */
3268 EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
3269
3270 resp.id = req.id;
3271 resp.error = -EPERM;
3272 resp.val = 0;
3273
3274 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3275 EXPECT_EQ(errno, ENOENT);
3276
3277 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3278
3279 resp.id = req.id;
3280 resp.error = -512; /* -ERESTARTSYS */
3281 resp.val = 0;
3282
3283 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3284
3285 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3286 EXPECT_EQ(true, WIFEXITED(status));
3287 EXPECT_EQ(0, WEXITSTATUS(status));
3288}
3289
3290TEST(user_notification_closed_listener)
3291{
3292 pid_t pid;
3293 long ret;
3294 int status, listener;
3295
Tycho Andersenc7140702019-01-18 17:12:16 -07003296 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3297 ASSERT_EQ(0, ret) {
3298 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3299 }
3300
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003301 listener = user_trap_syscall(__NR_getppid,
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003302 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Kees Cook3d244c12019-01-16 16:35:25 -08003303 ASSERT_GE(listener, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003304
3305 /*
3306 * Check that we get an ENOSYS when the listener is closed.
3307 */
3308 pid = fork();
3309 ASSERT_GE(pid, 0);
3310 if (pid == 0) {
3311 close(listener);
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003312 ret = syscall(__NR_getppid);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003313 exit(ret != -1 && errno != ENOSYS);
3314 }
3315
3316 close(listener);
3317
3318 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3319 EXPECT_EQ(true, WIFEXITED(status));
3320 EXPECT_EQ(0, WEXITSTATUS(status));
3321}
3322
3323/*
3324 * Check that a pid in a child namespace still shows up as valid in ours.
3325 */
3326TEST(user_notification_child_pid_ns)
3327{
3328 pid_t pid;
3329 int status, listener;
3330 struct seccomp_notif req = {};
3331 struct seccomp_notif_resp resp = {};
3332
Tycho Andersen30d53a52019-01-18 17:12:17 -07003333 ASSERT_EQ(unshare(CLONE_NEWUSER | CLONE_NEWPID), 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003334
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003335 listener = user_trap_syscall(__NR_getppid,
3336 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003337 ASSERT_GE(listener, 0);
3338
3339 pid = fork();
3340 ASSERT_GE(pid, 0);
3341
3342 if (pid == 0)
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003343 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003344
3345 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3346 EXPECT_EQ(req.pid, pid);
3347
3348 resp.id = req.id;
3349 resp.error = 0;
3350 resp.val = USER_NOTIF_MAGIC;
3351
3352 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3353
3354 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3355 EXPECT_EQ(true, WIFEXITED(status));
3356 EXPECT_EQ(0, WEXITSTATUS(status));
3357 close(listener);
3358}
3359
3360/*
3361 * Check that a pid in a sibling (i.e. unrelated) namespace shows up as 0, i.e.
3362 * invalid.
3363 */
3364TEST(user_notification_sibling_pid_ns)
3365{
3366 pid_t pid, pid2;
3367 int status, listener;
3368 struct seccomp_notif req = {};
3369 struct seccomp_notif_resp resp = {};
3370
Tycho Andersenc7140702019-01-18 17:12:16 -07003371 ASSERT_EQ(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0), 0) {
3372 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3373 }
3374
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003375 listener = user_trap_syscall(__NR_getppid,
3376 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003377 ASSERT_GE(listener, 0);
3378
3379 pid = fork();
3380 ASSERT_GE(pid, 0);
3381
3382 if (pid == 0) {
3383 ASSERT_EQ(unshare(CLONE_NEWPID), 0);
3384
3385 pid2 = fork();
3386 ASSERT_GE(pid2, 0);
3387
3388 if (pid2 == 0)
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003389 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003390
3391 EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
3392 EXPECT_EQ(true, WIFEXITED(status));
3393 EXPECT_EQ(0, WEXITSTATUS(status));
3394 exit(WEXITSTATUS(status));
3395 }
3396
3397 /* Create the sibling ns, and sibling in it. */
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003398 ASSERT_EQ(unshare(CLONE_NEWPID), 0);
3399 ASSERT_EQ(errno, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003400
3401 pid2 = fork();
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003402 ASSERT_GE(pid2, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003403
3404 if (pid2 == 0) {
3405 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3406 /*
3407 * The pid should be 0, i.e. the task is in some namespace that
3408 * we can't "see".
3409 */
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003410 EXPECT_EQ(req.pid, 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003411
3412 resp.id = req.id;
3413 resp.error = 0;
3414 resp.val = USER_NOTIF_MAGIC;
3415
3416 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3417 exit(0);
3418 }
3419
3420 close(listener);
3421
3422 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3423 EXPECT_EQ(true, WIFEXITED(status));
3424 EXPECT_EQ(0, WEXITSTATUS(status));
3425
3426 EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
3427 EXPECT_EQ(true, WIFEXITED(status));
3428 EXPECT_EQ(0, WEXITSTATUS(status));
3429}
3430
3431TEST(user_notification_fault_recv)
3432{
3433 pid_t pid;
3434 int status, listener;
3435 struct seccomp_notif req = {};
3436 struct seccomp_notif_resp resp = {};
3437
Tycho Andersen30d53a52019-01-18 17:12:17 -07003438 ASSERT_EQ(unshare(CLONE_NEWUSER), 0);
3439
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003440 listener = user_trap_syscall(__NR_getppid,
3441 SECCOMP_FILTER_FLAG_NEW_LISTENER);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003442 ASSERT_GE(listener, 0);
3443
3444 pid = fork();
3445 ASSERT_GE(pid, 0);
3446
3447 if (pid == 0)
Kees Cook9dd3fcb2019-04-11 16:56:31 -07003448 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003449
3450 /* Do a bad recv() */
3451 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, NULL), -1);
3452 EXPECT_EQ(errno, EFAULT);
3453
3454 /* We should still be able to receive this notification, though. */
3455 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3456 EXPECT_EQ(req.pid, pid);
3457
3458 resp.id = req.id;
3459 resp.error = 0;
3460 resp.val = USER_NOTIF_MAGIC;
3461
3462 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3463
3464 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3465 EXPECT_EQ(true, WIFEXITED(status));
3466 EXPECT_EQ(0, WEXITSTATUS(status));
3467}
3468
3469TEST(seccomp_get_notif_sizes)
3470{
3471 struct seccomp_notif_sizes sizes;
3472
Kees Cook3d244c12019-01-16 16:35:25 -08003473 ASSERT_EQ(seccomp(SECCOMP_GET_NOTIF_SIZES, 0, &sizes), 0);
Tycho Andersen6a21cc52018-12-09 11:24:13 -07003474 EXPECT_EQ(sizes.seccomp_notif, sizeof(struct seccomp_notif));
3475 EXPECT_EQ(sizes.seccomp_notif_resp, sizeof(struct seccomp_notif_resp));
3476}
3477
Kees Cookc99ee512015-06-16 10:54:14 -07003478/*
3479 * TODO:
3480 * - add microbenchmarks
3481 * - expand NNP testing
3482 * - better arch-specific TRACE and TRAP handlers.
3483 * - endianness checking when appropriate
3484 * - 64-bit arg prodding
3485 * - arch value testing (x86 modes especially)
Tyler Hickse66a3992017-08-11 04:33:56 +00003486 * - verify that FILTER_FLAG_LOG filters generate log messages
Tyler Hicks59f5cf42017-08-11 04:33:57 +00003487 * - verify that RET_LOG generates log messages
Kees Cookc99ee512015-06-16 10:54:14 -07003488 * - ...
3489 */
3490
3491TEST_HARNESS_MAIN