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selftests/seccomp: Remove syscall setting #ifdefs
[mirror_ubuntu-jammy-kernel.git] / tools / testing / selftests / seccomp / seccomp_bpf.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
4 *
5 * Test code for seccomp bpf.
6 */
7
8 #define _GNU_SOURCE
9 #include <sys/types.h>
10
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
22
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>
31 #include <pthread.h>
32 #include <semaphore.h>
33 #include <signal.h>
34 #include <stddef.h>
35 #include <stdbool.h>
36 #include <string.h>
37 #include <time.h>
38 #include <limits.h>
39 #include <linux/elf.h>
40 #include <sys/uio.h>
41 #include <sys/utsname.h>
42 #include <sys/fcntl.h>
43 #include <sys/mman.h>
44 #include <sys/times.h>
45 #include <sys/socket.h>
46 #include <sys/ioctl.h>
47 #include <linux/kcmp.h>
48 #include <sys/resource.h>
49
50 #include <unistd.h>
51 #include <sys/syscall.h>
52 #include <poll.h>
53
54 #include "../kselftest_harness.h"
55 #include "../clone3/clone3_selftests.h"
56
57 /* Attempt to de-conflict with the selftests tree. */
58 #ifndef SKIP
59 #define SKIP(s, ...) XFAIL(s, ##__VA_ARGS__)
60 #endif
61
62 #ifndef PR_SET_PTRACER
63 # define PR_SET_PTRACER 0x59616d61
64 #endif
65
66 #ifndef PR_SET_NO_NEW_PRIVS
67 #define PR_SET_NO_NEW_PRIVS 38
68 #define PR_GET_NO_NEW_PRIVS 39
69 #endif
70
71 #ifndef PR_SECCOMP_EXT
72 #define PR_SECCOMP_EXT 43
73 #endif
74
75 #ifndef SECCOMP_EXT_ACT
76 #define SECCOMP_EXT_ACT 1
77 #endif
78
79 #ifndef SECCOMP_EXT_ACT_TSYNC
80 #define SECCOMP_EXT_ACT_TSYNC 1
81 #endif
82
83 #ifndef SECCOMP_MODE_STRICT
84 #define SECCOMP_MODE_STRICT 1
85 #endif
86
87 #ifndef SECCOMP_MODE_FILTER
88 #define SECCOMP_MODE_FILTER 2
89 #endif
90
91 #ifndef SECCOMP_RET_ALLOW
92 struct seccomp_data {
93 int nr;
94 __u32 arch;
95 __u64 instruction_pointer;
96 __u64 args[6];
97 };
98 #endif
99
100 #ifndef SECCOMP_RET_KILL_PROCESS
101 #define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process */
102 #define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread */
103 #endif
104 #ifndef SECCOMP_RET_KILL
105 #define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD
106 #define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
107 #define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
108 #define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
109 #define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
110 #endif
111 #ifndef SECCOMP_RET_LOG
112 #define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */
113 #endif
114
115 #ifndef __NR_seccomp
116 # if defined(__i386__)
117 # define __NR_seccomp 354
118 # elif defined(__x86_64__)
119 # define __NR_seccomp 317
120 # elif defined(__arm__)
121 # define __NR_seccomp 383
122 # elif defined(__aarch64__)
123 # define __NR_seccomp 277
124 # elif defined(__riscv)
125 # define __NR_seccomp 277
126 # elif defined(__csky__)
127 # define __NR_seccomp 277
128 # elif defined(__hppa__)
129 # define __NR_seccomp 338
130 # elif defined(__powerpc__)
131 # define __NR_seccomp 358
132 # elif defined(__s390__)
133 # define __NR_seccomp 348
134 # elif defined(__xtensa__)
135 # define __NR_seccomp 337
136 # elif defined(__sh__)
137 # define __NR_seccomp 372
138 # else
139 # warning "seccomp syscall number unknown for this architecture"
140 # define __NR_seccomp 0xffff
141 # endif
142 #endif
143
144 #ifndef SECCOMP_SET_MODE_STRICT
145 #define SECCOMP_SET_MODE_STRICT 0
146 #endif
147
148 #ifndef SECCOMP_SET_MODE_FILTER
149 #define SECCOMP_SET_MODE_FILTER 1
150 #endif
151
152 #ifndef SECCOMP_GET_ACTION_AVAIL
153 #define SECCOMP_GET_ACTION_AVAIL 2
154 #endif
155
156 #ifndef SECCOMP_GET_NOTIF_SIZES
157 #define SECCOMP_GET_NOTIF_SIZES 3
158 #endif
159
160 #ifndef SECCOMP_FILTER_FLAG_TSYNC
161 #define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
162 #endif
163
164 #ifndef SECCOMP_FILTER_FLAG_LOG
165 #define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
166 #endif
167
168 #ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
169 #define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
170 #endif
171
172 #ifndef PTRACE_SECCOMP_GET_METADATA
173 #define PTRACE_SECCOMP_GET_METADATA 0x420d
174
175 struct seccomp_metadata {
176 __u64 filter_off; /* Input: which filter */
177 __u64 flags; /* Output: filter's flags */
178 };
179 #endif
180
181 #ifndef SECCOMP_FILTER_FLAG_NEW_LISTENER
182 #define SECCOMP_FILTER_FLAG_NEW_LISTENER (1UL << 3)
183 #endif
184
185 #ifndef SECCOMP_RET_USER_NOTIF
186 #define SECCOMP_RET_USER_NOTIF 0x7fc00000U
187
188 #define SECCOMP_IOC_MAGIC '!'
189 #define SECCOMP_IO(nr) _IO(SECCOMP_IOC_MAGIC, nr)
190 #define SECCOMP_IOR(nr, type) _IOR(SECCOMP_IOC_MAGIC, nr, type)
191 #define SECCOMP_IOW(nr, type) _IOW(SECCOMP_IOC_MAGIC, nr, type)
192 #define SECCOMP_IOWR(nr, type) _IOWR(SECCOMP_IOC_MAGIC, nr, type)
193
194 /* Flags for seccomp notification fd ioctl. */
195 #define SECCOMP_IOCTL_NOTIF_RECV SECCOMP_IOWR(0, struct seccomp_notif)
196 #define SECCOMP_IOCTL_NOTIF_SEND SECCOMP_IOWR(1, \
197 struct seccomp_notif_resp)
198 #define SECCOMP_IOCTL_NOTIF_ID_VALID SECCOMP_IOW(2, __u64)
199
200 struct seccomp_notif {
201 __u64 id;
202 __u32 pid;
203 __u32 flags;
204 struct seccomp_data data;
205 };
206
207 struct seccomp_notif_resp {
208 __u64 id;
209 __s64 val;
210 __s32 error;
211 __u32 flags;
212 };
213
214 struct seccomp_notif_sizes {
215 __u16 seccomp_notif;
216 __u16 seccomp_notif_resp;
217 __u16 seccomp_data;
218 };
219 #endif
220
221 #ifndef SECCOMP_IOCTL_NOTIF_ADDFD
222 /* On success, the return value is the remote process's added fd number */
223 #define SECCOMP_IOCTL_NOTIF_ADDFD SECCOMP_IOW(3, \
224 struct seccomp_notif_addfd)
225
226 /* valid flags for seccomp_notif_addfd */
227 #define SECCOMP_ADDFD_FLAG_SETFD (1UL << 0) /* Specify remote fd */
228
229 struct seccomp_notif_addfd {
230 __u64 id;
231 __u32 flags;
232 __u32 srcfd;
233 __u32 newfd;
234 __u32 newfd_flags;
235 };
236 #endif
237
238 struct seccomp_notif_addfd_small {
239 __u64 id;
240 char weird[4];
241 };
242 #define SECCOMP_IOCTL_NOTIF_ADDFD_SMALL \
243 SECCOMP_IOW(3, struct seccomp_notif_addfd_small)
244
245 struct seccomp_notif_addfd_big {
246 union {
247 struct seccomp_notif_addfd addfd;
248 char buf[sizeof(struct seccomp_notif_addfd) + 8];
249 };
250 };
251 #define SECCOMP_IOCTL_NOTIF_ADDFD_BIG \
252 SECCOMP_IOWR(3, struct seccomp_notif_addfd_big)
253
254 #ifndef PTRACE_EVENTMSG_SYSCALL_ENTRY
255 #define PTRACE_EVENTMSG_SYSCALL_ENTRY 1
256 #define PTRACE_EVENTMSG_SYSCALL_EXIT 2
257 #endif
258
259 #ifndef SECCOMP_USER_NOTIF_FLAG_CONTINUE
260 #define SECCOMP_USER_NOTIF_FLAG_CONTINUE 0x00000001
261 #endif
262
263 #ifndef SECCOMP_FILTER_FLAG_TSYNC_ESRCH
264 #define SECCOMP_FILTER_FLAG_TSYNC_ESRCH (1UL << 4)
265 #endif
266
267 #ifndef seccomp
268 int seccomp(unsigned int op, unsigned int flags, void *args)
269 {
270 errno = 0;
271 return syscall(__NR_seccomp, op, flags, args);
272 }
273 #endif
274
275 #if __BYTE_ORDER == __LITTLE_ENDIAN
276 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
277 #elif __BYTE_ORDER == __BIG_ENDIAN
278 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
279 #else
280 #error "wut? Unknown __BYTE_ORDER?!"
281 #endif
282
283 #define SIBLING_EXIT_UNKILLED 0xbadbeef
284 #define SIBLING_EXIT_FAILURE 0xbadface
285 #define SIBLING_EXIT_NEWPRIVS 0xbadfeed
286
287 static int __filecmp(pid_t pid1, pid_t pid2, int fd1, int fd2)
288 {
289 #ifdef __NR_kcmp
290 errno = 0;
291 return syscall(__NR_kcmp, pid1, pid2, KCMP_FILE, fd1, fd2);
292 #else
293 errno = ENOSYS;
294 return -1;
295 #endif
296 }
297
298 /* Have TH_LOG report actual location filecmp() is used. */
299 #define filecmp(pid1, pid2, fd1, fd2) ({ \
300 int _ret; \
301 \
302 _ret = __filecmp(pid1, pid2, fd1, fd2); \
303 if (_ret != 0) { \
304 if (_ret < 0 && errno == ENOSYS) { \
305 TH_LOG("kcmp() syscall missing (test is less accurate)");\
306 _ret = 0; \
307 } \
308 } \
309 _ret; })
310
311 TEST(kcmp)
312 {
313 int ret;
314
315 ret = __filecmp(getpid(), getpid(), 1, 1);
316 EXPECT_EQ(ret, 0);
317 if (ret != 0 && errno == ENOSYS)
318 SKIP(return, "Kernel does not support kcmp() (missing CONFIG_CHECKPOINT_RESTORE?)");
319 }
320
321 TEST(mode_strict_support)
322 {
323 long ret;
324
325 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
326 ASSERT_EQ(0, ret) {
327 TH_LOG("Kernel does not support CONFIG_SECCOMP");
328 }
329 syscall(__NR_exit, 0);
330 }
331
332 TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
333 {
334 long ret;
335
336 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
337 ASSERT_EQ(0, ret) {
338 TH_LOG("Kernel does not support CONFIG_SECCOMP");
339 }
340 syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
341 NULL, NULL, NULL);
342 EXPECT_FALSE(true) {
343 TH_LOG("Unreachable!");
344 }
345 }
346
347 /* Note! This doesn't test no new privs behavior */
348 TEST(no_new_privs_support)
349 {
350 long ret;
351
352 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
353 EXPECT_EQ(0, ret) {
354 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
355 }
356 }
357
358 /* Tests kernel support by checking for a copy_from_user() fault on NULL. */
359 TEST(mode_filter_support)
360 {
361 long ret;
362
363 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
364 ASSERT_EQ(0, ret) {
365 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
366 }
367 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
368 EXPECT_EQ(-1, ret);
369 EXPECT_EQ(EFAULT, errno) {
370 TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
371 }
372 }
373
374 TEST(mode_filter_without_nnp)
375 {
376 struct sock_filter filter[] = {
377 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
378 };
379 struct sock_fprog prog = {
380 .len = (unsigned short)ARRAY_SIZE(filter),
381 .filter = filter,
382 };
383 long ret;
384
385 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
386 ASSERT_LE(0, ret) {
387 TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
388 }
389 errno = 0;
390 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
391 /* Succeeds with CAP_SYS_ADMIN, fails without */
392 /* TODO(wad) check caps not euid */
393 if (geteuid()) {
394 EXPECT_EQ(-1, ret);
395 EXPECT_EQ(EACCES, errno);
396 } else {
397 EXPECT_EQ(0, ret);
398 }
399 }
400
401 #define MAX_INSNS_PER_PATH 32768
402
403 TEST(filter_size_limits)
404 {
405 int i;
406 int count = BPF_MAXINSNS + 1;
407 struct sock_filter allow[] = {
408 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
409 };
410 struct sock_filter *filter;
411 struct sock_fprog prog = { };
412 long ret;
413
414 filter = calloc(count, sizeof(*filter));
415 ASSERT_NE(NULL, filter);
416
417 for (i = 0; i < count; i++)
418 filter[i] = allow[0];
419
420 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
421 ASSERT_EQ(0, ret);
422
423 prog.filter = filter;
424 prog.len = count;
425
426 /* Too many filter instructions in a single filter. */
427 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
428 ASSERT_NE(0, ret) {
429 TH_LOG("Installing %d insn filter was allowed", prog.len);
430 }
431
432 /* One less is okay, though. */
433 prog.len -= 1;
434 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
435 ASSERT_EQ(0, ret) {
436 TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
437 }
438 }
439
440 TEST(filter_chain_limits)
441 {
442 int i;
443 int count = BPF_MAXINSNS;
444 struct sock_filter allow[] = {
445 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
446 };
447 struct sock_filter *filter;
448 struct sock_fprog prog = { };
449 long ret;
450
451 filter = calloc(count, sizeof(*filter));
452 ASSERT_NE(NULL, filter);
453
454 for (i = 0; i < count; i++)
455 filter[i] = allow[0];
456
457 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
458 ASSERT_EQ(0, ret);
459
460 prog.filter = filter;
461 prog.len = 1;
462
463 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
464 ASSERT_EQ(0, ret);
465
466 prog.len = count;
467
468 /* Too many total filter instructions. */
469 for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
470 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
471 if (ret != 0)
472 break;
473 }
474 ASSERT_NE(0, ret) {
475 TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
476 i, count, i * (count + 4));
477 }
478 }
479
480 TEST(mode_filter_cannot_move_to_strict)
481 {
482 struct sock_filter filter[] = {
483 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
484 };
485 struct sock_fprog prog = {
486 .len = (unsigned short)ARRAY_SIZE(filter),
487 .filter = filter,
488 };
489 long ret;
490
491 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
492 ASSERT_EQ(0, ret);
493
494 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
495 ASSERT_EQ(0, ret);
496
497 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
498 EXPECT_EQ(-1, ret);
499 EXPECT_EQ(EINVAL, errno);
500 }
501
502
503 TEST(mode_filter_get_seccomp)
504 {
505 struct sock_filter filter[] = {
506 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
507 };
508 struct sock_fprog prog = {
509 .len = (unsigned short)ARRAY_SIZE(filter),
510 .filter = filter,
511 };
512 long ret;
513
514 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
515 ASSERT_EQ(0, ret);
516
517 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
518 EXPECT_EQ(0, ret);
519
520 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
521 ASSERT_EQ(0, ret);
522
523 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
524 EXPECT_EQ(2, ret);
525 }
526
527
528 TEST(ALLOW_all)
529 {
530 struct sock_filter filter[] = {
531 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
532 };
533 struct sock_fprog prog = {
534 .len = (unsigned short)ARRAY_SIZE(filter),
535 .filter = filter,
536 };
537 long ret;
538
539 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
540 ASSERT_EQ(0, ret);
541
542 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
543 ASSERT_EQ(0, ret);
544 }
545
546 TEST(empty_prog)
547 {
548 struct sock_filter filter[] = {
549 };
550 struct sock_fprog prog = {
551 .len = (unsigned short)ARRAY_SIZE(filter),
552 .filter = filter,
553 };
554 long ret;
555
556 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
557 ASSERT_EQ(0, ret);
558
559 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
560 EXPECT_EQ(-1, ret);
561 EXPECT_EQ(EINVAL, errno);
562 }
563
564 TEST(log_all)
565 {
566 struct sock_filter filter[] = {
567 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
568 };
569 struct sock_fprog prog = {
570 .len = (unsigned short)ARRAY_SIZE(filter),
571 .filter = filter,
572 };
573 long ret;
574 pid_t parent = getppid();
575
576 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
577 ASSERT_EQ(0, ret);
578
579 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
580 ASSERT_EQ(0, ret);
581
582 /* getppid() should succeed and be logged (no check for logging) */
583 EXPECT_EQ(parent, syscall(__NR_getppid));
584 }
585
586 TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
587 {
588 struct sock_filter filter[] = {
589 BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
590 };
591 struct sock_fprog prog = {
592 .len = (unsigned short)ARRAY_SIZE(filter),
593 .filter = filter,
594 };
595 long ret;
596
597 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
598 ASSERT_EQ(0, ret);
599
600 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
601 ASSERT_EQ(0, ret);
602 EXPECT_EQ(0, syscall(__NR_getpid)) {
603 TH_LOG("getpid() shouldn't ever return");
604 }
605 }
606
607 /* return code >= 0x80000000 is unused. */
608 TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
609 {
610 struct sock_filter filter[] = {
611 BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
612 };
613 struct sock_fprog prog = {
614 .len = (unsigned short)ARRAY_SIZE(filter),
615 .filter = filter,
616 };
617 long ret;
618
619 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
620 ASSERT_EQ(0, ret);
621
622 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
623 ASSERT_EQ(0, ret);
624 EXPECT_EQ(0, syscall(__NR_getpid)) {
625 TH_LOG("getpid() shouldn't ever return");
626 }
627 }
628
629 TEST_SIGNAL(KILL_all, SIGSYS)
630 {
631 struct sock_filter filter[] = {
632 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
633 };
634 struct sock_fprog prog = {
635 .len = (unsigned short)ARRAY_SIZE(filter),
636 .filter = filter,
637 };
638 long ret;
639
640 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
641 ASSERT_EQ(0, ret);
642
643 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
644 ASSERT_EQ(0, ret);
645 }
646
647 TEST_SIGNAL(KILL_one, SIGSYS)
648 {
649 struct sock_filter filter[] = {
650 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
651 offsetof(struct seccomp_data, nr)),
652 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
653 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
654 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
655 };
656 struct sock_fprog prog = {
657 .len = (unsigned short)ARRAY_SIZE(filter),
658 .filter = filter,
659 };
660 long ret;
661 pid_t parent = getppid();
662
663 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
664 ASSERT_EQ(0, ret);
665
666 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
667 ASSERT_EQ(0, ret);
668
669 EXPECT_EQ(parent, syscall(__NR_getppid));
670 /* getpid() should never return. */
671 EXPECT_EQ(0, syscall(__NR_getpid));
672 }
673
674 TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
675 {
676 void *fatal_address;
677 struct sock_filter filter[] = {
678 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
679 offsetof(struct seccomp_data, nr)),
680 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0),
681 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
682 /* Only both with lower 32-bit for now. */
683 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
684 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
685 (unsigned long)&fatal_address, 0, 1),
686 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
687 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
688 };
689 struct sock_fprog prog = {
690 .len = (unsigned short)ARRAY_SIZE(filter),
691 .filter = filter,
692 };
693 long ret;
694 pid_t parent = getppid();
695 struct tms timebuf;
696 clock_t clock = times(&timebuf);
697
698 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
699 ASSERT_EQ(0, ret);
700
701 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
702 ASSERT_EQ(0, ret);
703
704 EXPECT_EQ(parent, syscall(__NR_getppid));
705 EXPECT_LE(clock, syscall(__NR_times, &timebuf));
706 /* times() should never return. */
707 EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
708 }
709
710 TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
711 {
712 #ifndef __NR_mmap2
713 int sysno = __NR_mmap;
714 #else
715 int sysno = __NR_mmap2;
716 #endif
717 struct sock_filter filter[] = {
718 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
719 offsetof(struct seccomp_data, nr)),
720 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0),
721 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
722 /* Only both with lower 32-bit for now. */
723 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
724 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
725 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
726 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
727 };
728 struct sock_fprog prog = {
729 .len = (unsigned short)ARRAY_SIZE(filter),
730 .filter = filter,
731 };
732 long ret;
733 pid_t parent = getppid();
734 int fd;
735 void *map1, *map2;
736 int page_size = sysconf(_SC_PAGESIZE);
737
738 ASSERT_LT(0, page_size);
739
740 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
741 ASSERT_EQ(0, ret);
742
743 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
744 ASSERT_EQ(0, ret);
745
746 fd = open("/dev/zero", O_RDONLY);
747 ASSERT_NE(-1, fd);
748
749 EXPECT_EQ(parent, syscall(__NR_getppid));
750 map1 = (void *)syscall(sysno,
751 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
752 EXPECT_NE(MAP_FAILED, map1);
753 /* mmap2() should never return. */
754 map2 = (void *)syscall(sysno,
755 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
756 EXPECT_EQ(MAP_FAILED, map2);
757
758 /* The test failed, so clean up the resources. */
759 munmap(map1, page_size);
760 munmap(map2, page_size);
761 close(fd);
762 }
763
764 /* This is a thread task to die via seccomp filter violation. */
765 void *kill_thread(void *data)
766 {
767 bool die = (bool)data;
768
769 if (die) {
770 prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
771 return (void *)SIBLING_EXIT_FAILURE;
772 }
773
774 return (void *)SIBLING_EXIT_UNKILLED;
775 }
776
777 enum kill_t {
778 KILL_THREAD,
779 KILL_PROCESS,
780 RET_UNKNOWN
781 };
782
783 /* Prepare a thread that will kill itself or both of us. */
784 void kill_thread_or_group(struct __test_metadata *_metadata,
785 enum kill_t kill_how)
786 {
787 pthread_t thread;
788 void *status;
789 /* Kill only when calling __NR_prctl. */
790 struct sock_filter filter_thread[] = {
791 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
792 offsetof(struct seccomp_data, nr)),
793 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
794 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
795 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
796 };
797 struct sock_fprog prog_thread = {
798 .len = (unsigned short)ARRAY_SIZE(filter_thread),
799 .filter = filter_thread,
800 };
801 int kill = kill_how == KILL_PROCESS ? SECCOMP_RET_KILL_PROCESS : 0xAAAAAAAAA;
802 struct sock_filter filter_process[] = {
803 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
804 offsetof(struct seccomp_data, nr)),
805 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
806 BPF_STMT(BPF_RET|BPF_K, kill),
807 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
808 };
809 struct sock_fprog prog_process = {
810 .len = (unsigned short)ARRAY_SIZE(filter_process),
811 .filter = filter_process,
812 };
813
814 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
815 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
816 }
817
818 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
819 kill_how == KILL_THREAD ? &prog_thread
820 : &prog_process));
821
822 /*
823 * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
824 * flag cannot be downgraded by a new filter.
825 */
826 if (kill_how == KILL_PROCESS)
827 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
828
829 /* Start a thread that will exit immediately. */
830 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
831 ASSERT_EQ(0, pthread_join(thread, &status));
832 ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
833
834 /* Start a thread that will die immediately. */
835 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
836 ASSERT_EQ(0, pthread_join(thread, &status));
837 ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
838
839 /*
840 * If we get here, only the spawned thread died. Let the parent know
841 * the whole process didn't die (i.e. this thread, the spawner,
842 * stayed running).
843 */
844 exit(42);
845 }
846
847 TEST(KILL_thread)
848 {
849 int status;
850 pid_t child_pid;
851
852 child_pid = fork();
853 ASSERT_LE(0, child_pid);
854 if (child_pid == 0) {
855 kill_thread_or_group(_metadata, KILL_THREAD);
856 _exit(38);
857 }
858
859 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
860
861 /* If only the thread was killed, we'll see exit 42. */
862 ASSERT_TRUE(WIFEXITED(status));
863 ASSERT_EQ(42, WEXITSTATUS(status));
864 }
865
866 TEST(KILL_process)
867 {
868 int status;
869 pid_t child_pid;
870
871 child_pid = fork();
872 ASSERT_LE(0, child_pid);
873 if (child_pid == 0) {
874 kill_thread_or_group(_metadata, KILL_PROCESS);
875 _exit(38);
876 }
877
878 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
879
880 /* If the entire process was killed, we'll see SIGSYS. */
881 ASSERT_TRUE(WIFSIGNALED(status));
882 ASSERT_EQ(SIGSYS, WTERMSIG(status));
883 }
884
885 TEST(KILL_unknown)
886 {
887 int status;
888 pid_t child_pid;
889
890 child_pid = fork();
891 ASSERT_LE(0, child_pid);
892 if (child_pid == 0) {
893 kill_thread_or_group(_metadata, RET_UNKNOWN);
894 _exit(38);
895 }
896
897 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
898
899 /* If the entire process was killed, we'll see SIGSYS. */
900 EXPECT_TRUE(WIFSIGNALED(status)) {
901 TH_LOG("Unknown SECCOMP_RET is only killing the thread?");
902 }
903 ASSERT_EQ(SIGSYS, WTERMSIG(status));
904 }
905
906 /* TODO(wad) add 64-bit versus 32-bit arg tests. */
907 TEST(arg_out_of_range)
908 {
909 struct sock_filter filter[] = {
910 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
911 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
912 };
913 struct sock_fprog prog = {
914 .len = (unsigned short)ARRAY_SIZE(filter),
915 .filter = filter,
916 };
917 long ret;
918
919 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
920 ASSERT_EQ(0, ret);
921
922 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
923 EXPECT_EQ(-1, ret);
924 EXPECT_EQ(EINVAL, errno);
925 }
926
927 #define ERRNO_FILTER(name, errno) \
928 struct sock_filter _read_filter_##name[] = { \
929 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, \
930 offsetof(struct seccomp_data, nr)), \
931 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), \
932 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | errno), \
933 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), \
934 }; \
935 struct sock_fprog prog_##name = { \
936 .len = (unsigned short)ARRAY_SIZE(_read_filter_##name), \
937 .filter = _read_filter_##name, \
938 }
939
940 /* Make sure basic errno values are correctly passed through a filter. */
941 TEST(ERRNO_valid)
942 {
943 ERRNO_FILTER(valid, E2BIG);
944 long ret;
945 pid_t parent = getppid();
946
947 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
948 ASSERT_EQ(0, ret);
949
950 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_valid);
951 ASSERT_EQ(0, ret);
952
953 EXPECT_EQ(parent, syscall(__NR_getppid));
954 EXPECT_EQ(-1, read(0, NULL, 0));
955 EXPECT_EQ(E2BIG, errno);
956 }
957
958 /* Make sure an errno of zero is correctly handled by the arch code. */
959 TEST(ERRNO_zero)
960 {
961 ERRNO_FILTER(zero, 0);
962 long ret;
963 pid_t parent = getppid();
964
965 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
966 ASSERT_EQ(0, ret);
967
968 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_zero);
969 ASSERT_EQ(0, ret);
970
971 EXPECT_EQ(parent, syscall(__NR_getppid));
972 /* "errno" of 0 is ok. */
973 EXPECT_EQ(0, read(0, NULL, 0));
974 }
975
976 /*
977 * The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
978 * This tests that the errno value gets capped correctly, fixed by
979 * 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
980 */
981 TEST(ERRNO_capped)
982 {
983 ERRNO_FILTER(capped, 4096);
984 long ret;
985 pid_t parent = getppid();
986
987 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
988 ASSERT_EQ(0, ret);
989
990 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_capped);
991 ASSERT_EQ(0, ret);
992
993 EXPECT_EQ(parent, syscall(__NR_getppid));
994 EXPECT_EQ(-1, read(0, NULL, 0));
995 EXPECT_EQ(4095, errno);
996 }
997
998 /*
999 * Filters are processed in reverse order: last applied is executed first.
1000 * Since only the SECCOMP_RET_ACTION mask is tested for return values, the
1001 * SECCOMP_RET_DATA mask results will follow the most recently applied
1002 * matching filter return (and not the lowest or highest value).
1003 */
1004 TEST(ERRNO_order)
1005 {
1006 ERRNO_FILTER(first, 11);
1007 ERRNO_FILTER(second, 13);
1008 ERRNO_FILTER(third, 12);
1009 long ret;
1010 pid_t parent = getppid();
1011
1012 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1013 ASSERT_EQ(0, ret);
1014
1015 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_first);
1016 ASSERT_EQ(0, ret);
1017
1018 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_second);
1019 ASSERT_EQ(0, ret);
1020
1021 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_third);
1022 ASSERT_EQ(0, ret);
1023
1024 EXPECT_EQ(parent, syscall(__NR_getppid));
1025 EXPECT_EQ(-1, read(0, NULL, 0));
1026 EXPECT_EQ(12, errno);
1027 }
1028
1029 FIXTURE(TRAP) {
1030 struct sock_fprog prog;
1031 };
1032
1033 FIXTURE_SETUP(TRAP)
1034 {
1035 struct sock_filter filter[] = {
1036 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1037 offsetof(struct seccomp_data, nr)),
1038 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1039 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
1040 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1041 };
1042
1043 memset(&self->prog, 0, sizeof(self->prog));
1044 self->prog.filter = malloc(sizeof(filter));
1045 ASSERT_NE(NULL, self->prog.filter);
1046 memcpy(self->prog.filter, filter, sizeof(filter));
1047 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1048 }
1049
1050 FIXTURE_TEARDOWN(TRAP)
1051 {
1052 if (self->prog.filter)
1053 free(self->prog.filter);
1054 }
1055
1056 TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
1057 {
1058 long ret;
1059
1060 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1061 ASSERT_EQ(0, ret);
1062
1063 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
1064 ASSERT_EQ(0, ret);
1065 syscall(__NR_getpid);
1066 }
1067
1068 /* Ensure that SIGSYS overrides SIG_IGN */
1069 TEST_F_SIGNAL(TRAP, ign, SIGSYS)
1070 {
1071 long ret;
1072
1073 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1074 ASSERT_EQ(0, ret);
1075
1076 signal(SIGSYS, SIG_IGN);
1077
1078 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
1079 ASSERT_EQ(0, ret);
1080 syscall(__NR_getpid);
1081 }
1082
1083 static siginfo_t TRAP_info;
1084 static volatile int TRAP_nr;
1085 static void TRAP_action(int nr, siginfo_t *info, void *void_context)
1086 {
1087 memcpy(&TRAP_info, info, sizeof(TRAP_info));
1088 TRAP_nr = nr;
1089 }
1090
1091 TEST_F(TRAP, handler)
1092 {
1093 int ret, test;
1094 struct sigaction act;
1095 sigset_t mask;
1096
1097 memset(&act, 0, sizeof(act));
1098 sigemptyset(&mask);
1099 sigaddset(&mask, SIGSYS);
1100
1101 act.sa_sigaction = &TRAP_action;
1102 act.sa_flags = SA_SIGINFO;
1103 ret = sigaction(SIGSYS, &act, NULL);
1104 ASSERT_EQ(0, ret) {
1105 TH_LOG("sigaction failed");
1106 }
1107 ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
1108 ASSERT_EQ(0, ret) {
1109 TH_LOG("sigprocmask failed");
1110 }
1111
1112 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1113 ASSERT_EQ(0, ret);
1114 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
1115 ASSERT_EQ(0, ret);
1116 TRAP_nr = 0;
1117 memset(&TRAP_info, 0, sizeof(TRAP_info));
1118 /* Expect the registers to be rolled back. (nr = error) may vary
1119 * based on arch. */
1120 ret = syscall(__NR_getpid);
1121 /* Silence gcc warning about volatile. */
1122 test = TRAP_nr;
1123 EXPECT_EQ(SIGSYS, test);
1124 struct local_sigsys {
1125 void *_call_addr; /* calling user insn */
1126 int _syscall; /* triggering system call number */
1127 unsigned int _arch; /* AUDIT_ARCH_* of syscall */
1128 } *sigsys = (struct local_sigsys *)
1129 #ifdef si_syscall
1130 &(TRAP_info.si_call_addr);
1131 #else
1132 &TRAP_info.si_pid;
1133 #endif
1134 EXPECT_EQ(__NR_getpid, sigsys->_syscall);
1135 /* Make sure arch is non-zero. */
1136 EXPECT_NE(0, sigsys->_arch);
1137 EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
1138 }
1139
1140 FIXTURE(precedence) {
1141 struct sock_fprog allow;
1142 struct sock_fprog log;
1143 struct sock_fprog trace;
1144 struct sock_fprog error;
1145 struct sock_fprog trap;
1146 struct sock_fprog kill;
1147 };
1148
1149 FIXTURE_SETUP(precedence)
1150 {
1151 struct sock_filter allow_insns[] = {
1152 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1153 };
1154 struct sock_filter log_insns[] = {
1155 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1156 offsetof(struct seccomp_data, nr)),
1157 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1158 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1159 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
1160 };
1161 struct sock_filter trace_insns[] = {
1162 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1163 offsetof(struct seccomp_data, nr)),
1164 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1165 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1166 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE),
1167 };
1168 struct sock_filter error_insns[] = {
1169 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1170 offsetof(struct seccomp_data, nr)),
1171 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1172 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1173 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO),
1174 };
1175 struct sock_filter trap_insns[] = {
1176 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1177 offsetof(struct seccomp_data, nr)),
1178 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1179 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1180 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
1181 };
1182 struct sock_filter kill_insns[] = {
1183 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1184 offsetof(struct seccomp_data, nr)),
1185 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1186 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1187 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1188 };
1189
1190 memset(self, 0, sizeof(*self));
1191 #define FILTER_ALLOC(_x) \
1192 self->_x.filter = malloc(sizeof(_x##_insns)); \
1193 ASSERT_NE(NULL, self->_x.filter); \
1194 memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
1195 self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
1196 FILTER_ALLOC(allow);
1197 FILTER_ALLOC(log);
1198 FILTER_ALLOC(trace);
1199 FILTER_ALLOC(error);
1200 FILTER_ALLOC(trap);
1201 FILTER_ALLOC(kill);
1202 }
1203
1204 FIXTURE_TEARDOWN(precedence)
1205 {
1206 #define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
1207 FILTER_FREE(allow);
1208 FILTER_FREE(log);
1209 FILTER_FREE(trace);
1210 FILTER_FREE(error);
1211 FILTER_FREE(trap);
1212 FILTER_FREE(kill);
1213 }
1214
1215 TEST_F(precedence, allow_ok)
1216 {
1217 pid_t parent, res = 0;
1218 long ret;
1219
1220 parent = getppid();
1221 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1222 ASSERT_EQ(0, ret);
1223
1224 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1225 ASSERT_EQ(0, ret);
1226 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1227 ASSERT_EQ(0, ret);
1228 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1229 ASSERT_EQ(0, ret);
1230 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1231 ASSERT_EQ(0, ret);
1232 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1233 ASSERT_EQ(0, ret);
1234 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1235 ASSERT_EQ(0, ret);
1236 /* Should work just fine. */
1237 res = syscall(__NR_getppid);
1238 EXPECT_EQ(parent, res);
1239 }
1240
1241 TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
1242 {
1243 pid_t parent, res = 0;
1244 long ret;
1245
1246 parent = getppid();
1247 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1248 ASSERT_EQ(0, ret);
1249
1250 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1251 ASSERT_EQ(0, ret);
1252 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1253 ASSERT_EQ(0, ret);
1254 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1255 ASSERT_EQ(0, ret);
1256 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1257 ASSERT_EQ(0, ret);
1258 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1259 ASSERT_EQ(0, ret);
1260 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1261 ASSERT_EQ(0, ret);
1262 /* Should work just fine. */
1263 res = syscall(__NR_getppid);
1264 EXPECT_EQ(parent, res);
1265 /* getpid() should never return. */
1266 res = syscall(__NR_getpid);
1267 EXPECT_EQ(0, res);
1268 }
1269
1270 TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
1271 {
1272 pid_t parent;
1273 long ret;
1274
1275 parent = getppid();
1276 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1277 ASSERT_EQ(0, ret);
1278
1279 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1280 ASSERT_EQ(0, ret);
1281 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1282 ASSERT_EQ(0, ret);
1283 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1284 ASSERT_EQ(0, ret);
1285 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1286 ASSERT_EQ(0, ret);
1287 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1288 ASSERT_EQ(0, ret);
1289 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1290 ASSERT_EQ(0, ret);
1291 /* Should work just fine. */
1292 EXPECT_EQ(parent, syscall(__NR_getppid));
1293 /* getpid() should never return. */
1294 EXPECT_EQ(0, syscall(__NR_getpid));
1295 }
1296
1297 TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
1298 {
1299 pid_t parent;
1300 long ret;
1301
1302 parent = getppid();
1303 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1304 ASSERT_EQ(0, ret);
1305
1306 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1307 ASSERT_EQ(0, ret);
1308 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1309 ASSERT_EQ(0, ret);
1310 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1311 ASSERT_EQ(0, ret);
1312 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1313 ASSERT_EQ(0, ret);
1314 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1315 ASSERT_EQ(0, ret);
1316 /* Should work just fine. */
1317 EXPECT_EQ(parent, syscall(__NR_getppid));
1318 /* getpid() should never return. */
1319 EXPECT_EQ(0, syscall(__NR_getpid));
1320 }
1321
1322 TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
1323 {
1324 pid_t parent;
1325 long ret;
1326
1327 parent = getppid();
1328 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1329 ASSERT_EQ(0, ret);
1330
1331 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1332 ASSERT_EQ(0, ret);
1333 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1334 ASSERT_EQ(0, ret);
1335 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1336 ASSERT_EQ(0, ret);
1337 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1338 ASSERT_EQ(0, ret);
1339 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1340 ASSERT_EQ(0, ret);
1341 /* Should work just fine. */
1342 EXPECT_EQ(parent, syscall(__NR_getppid));
1343 /* getpid() should never return. */
1344 EXPECT_EQ(0, syscall(__NR_getpid));
1345 }
1346
1347 TEST_F(precedence, errno_is_third)
1348 {
1349 pid_t parent;
1350 long ret;
1351
1352 parent = getppid();
1353 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1354 ASSERT_EQ(0, ret);
1355
1356 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1357 ASSERT_EQ(0, ret);
1358 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1359 ASSERT_EQ(0, ret);
1360 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1361 ASSERT_EQ(0, ret);
1362 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1363 ASSERT_EQ(0, ret);
1364 /* Should work just fine. */
1365 EXPECT_EQ(parent, syscall(__NR_getppid));
1366 EXPECT_EQ(0, syscall(__NR_getpid));
1367 }
1368
1369 TEST_F(precedence, errno_is_third_in_any_order)
1370 {
1371 pid_t parent;
1372 long ret;
1373
1374 parent = getppid();
1375 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1376 ASSERT_EQ(0, ret);
1377
1378 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1379 ASSERT_EQ(0, ret);
1380 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1381 ASSERT_EQ(0, ret);
1382 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1383 ASSERT_EQ(0, ret);
1384 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1385 ASSERT_EQ(0, ret);
1386 /* Should work just fine. */
1387 EXPECT_EQ(parent, syscall(__NR_getppid));
1388 EXPECT_EQ(0, syscall(__NR_getpid));
1389 }
1390
1391 TEST_F(precedence, trace_is_fourth)
1392 {
1393 pid_t parent;
1394 long ret;
1395
1396 parent = getppid();
1397 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1398 ASSERT_EQ(0, ret);
1399
1400 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1401 ASSERT_EQ(0, ret);
1402 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1403 ASSERT_EQ(0, ret);
1404 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1405 ASSERT_EQ(0, ret);
1406 /* Should work just fine. */
1407 EXPECT_EQ(parent, syscall(__NR_getppid));
1408 /* No ptracer */
1409 EXPECT_EQ(-1, syscall(__NR_getpid));
1410 }
1411
1412 TEST_F(precedence, trace_is_fourth_in_any_order)
1413 {
1414 pid_t parent;
1415 long ret;
1416
1417 parent = getppid();
1418 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1419 ASSERT_EQ(0, ret);
1420
1421 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1422 ASSERT_EQ(0, ret);
1423 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1424 ASSERT_EQ(0, ret);
1425 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1426 ASSERT_EQ(0, ret);
1427 /* Should work just fine. */
1428 EXPECT_EQ(parent, syscall(__NR_getppid));
1429 /* No ptracer */
1430 EXPECT_EQ(-1, syscall(__NR_getpid));
1431 }
1432
1433 TEST_F(precedence, log_is_fifth)
1434 {
1435 pid_t mypid, parent;
1436 long ret;
1437
1438 mypid = getpid();
1439 parent = getppid();
1440 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1441 ASSERT_EQ(0, ret);
1442
1443 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1444 ASSERT_EQ(0, ret);
1445 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1446 ASSERT_EQ(0, ret);
1447 /* Should work just fine. */
1448 EXPECT_EQ(parent, syscall(__NR_getppid));
1449 /* Should also work just fine */
1450 EXPECT_EQ(mypid, syscall(__NR_getpid));
1451 }
1452
1453 TEST_F(precedence, log_is_fifth_in_any_order)
1454 {
1455 pid_t mypid, parent;
1456 long ret;
1457
1458 mypid = getpid();
1459 parent = getppid();
1460 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1461 ASSERT_EQ(0, ret);
1462
1463 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1464 ASSERT_EQ(0, ret);
1465 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1466 ASSERT_EQ(0, ret);
1467 /* Should work just fine. */
1468 EXPECT_EQ(parent, syscall(__NR_getppid));
1469 /* Should also work just fine */
1470 EXPECT_EQ(mypid, syscall(__NR_getpid));
1471 }
1472
1473 #ifndef PTRACE_O_TRACESECCOMP
1474 #define PTRACE_O_TRACESECCOMP 0x00000080
1475 #endif
1476
1477 /* Catch the Ubuntu 12.04 value error. */
1478 #if PTRACE_EVENT_SECCOMP != 7
1479 #undef PTRACE_EVENT_SECCOMP
1480 #endif
1481
1482 #ifndef PTRACE_EVENT_SECCOMP
1483 #define PTRACE_EVENT_SECCOMP 7
1484 #endif
1485
1486 #define IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP)
1487 bool tracer_running;
1488 void tracer_stop(int sig)
1489 {
1490 tracer_running = false;
1491 }
1492
1493 typedef void tracer_func_t(struct __test_metadata *_metadata,
1494 pid_t tracee, int status, void *args);
1495
1496 void start_tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
1497 tracer_func_t tracer_func, void *args, bool ptrace_syscall)
1498 {
1499 int ret = -1;
1500 struct sigaction action = {
1501 .sa_handler = tracer_stop,
1502 };
1503
1504 /* Allow external shutdown. */
1505 tracer_running = true;
1506 ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));
1507
1508 errno = 0;
1509 while (ret == -1 && errno != EINVAL)
1510 ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
1511 ASSERT_EQ(0, ret) {
1512 kill(tracee, SIGKILL);
1513 }
1514 /* Wait for attach stop */
1515 wait(NULL);
1516
1517 ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, ptrace_syscall ?
1518 PTRACE_O_TRACESYSGOOD :
1519 PTRACE_O_TRACESECCOMP);
1520 ASSERT_EQ(0, ret) {
1521 TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
1522 kill(tracee, SIGKILL);
1523 }
1524 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1525 tracee, NULL, 0);
1526 ASSERT_EQ(0, ret);
1527
1528 /* Unblock the tracee */
1529 ASSERT_EQ(1, write(fd, "A", 1));
1530 ASSERT_EQ(0, close(fd));
1531
1532 /* Run until we're shut down. Must assert to stop execution. */
1533 while (tracer_running) {
1534 int status;
1535
1536 if (wait(&status) != tracee)
1537 continue;
1538 if (WIFSIGNALED(status) || WIFEXITED(status))
1539 /* Child is dead. Time to go. */
1540 return;
1541
1542 /* Check if this is a seccomp event. */
1543 ASSERT_EQ(!ptrace_syscall, IS_SECCOMP_EVENT(status));
1544
1545 tracer_func(_metadata, tracee, status, args);
1546
1547 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1548 tracee, NULL, 0);
1549 ASSERT_EQ(0, ret);
1550 }
1551 /* Directly report the status of our test harness results. */
1552 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
1553 }
1554
1555 /* Common tracer setup/teardown functions. */
1556 void cont_handler(int num)
1557 { }
1558 pid_t setup_trace_fixture(struct __test_metadata *_metadata,
1559 tracer_func_t func, void *args, bool ptrace_syscall)
1560 {
1561 char sync;
1562 int pipefd[2];
1563 pid_t tracer_pid;
1564 pid_t tracee = getpid();
1565
1566 /* Setup a pipe for clean synchronization. */
1567 ASSERT_EQ(0, pipe(pipefd));
1568
1569 /* Fork a child which we'll promote to tracer */
1570 tracer_pid = fork();
1571 ASSERT_LE(0, tracer_pid);
1572 signal(SIGALRM, cont_handler);
1573 if (tracer_pid == 0) {
1574 close(pipefd[0]);
1575 start_tracer(_metadata, pipefd[1], tracee, func, args,
1576 ptrace_syscall);
1577 syscall(__NR_exit, 0);
1578 }
1579 close(pipefd[1]);
1580 prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
1581 read(pipefd[0], &sync, 1);
1582 close(pipefd[0]);
1583
1584 return tracer_pid;
1585 }
1586
1587 void teardown_trace_fixture(struct __test_metadata *_metadata,
1588 pid_t tracer)
1589 {
1590 if (tracer) {
1591 int status;
1592 /*
1593 * Extract the exit code from the other process and
1594 * adopt it for ourselves in case its asserts failed.
1595 */
1596 ASSERT_EQ(0, kill(tracer, SIGUSR1));
1597 ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
1598 if (WEXITSTATUS(status))
1599 _metadata->passed = 0;
1600 }
1601 }
1602
1603 /* "poke" tracer arguments and function. */
1604 struct tracer_args_poke_t {
1605 unsigned long poke_addr;
1606 };
1607
1608 void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
1609 void *args)
1610 {
1611 int ret;
1612 unsigned long msg;
1613 struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;
1614
1615 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1616 EXPECT_EQ(0, ret);
1617 /* If this fails, don't try to recover. */
1618 ASSERT_EQ(0x1001, msg) {
1619 kill(tracee, SIGKILL);
1620 }
1621 /*
1622 * Poke in the message.
1623 * Registers are not touched to try to keep this relatively arch
1624 * agnostic.
1625 */
1626 ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
1627 EXPECT_EQ(0, ret);
1628 }
1629
1630 FIXTURE(TRACE_poke) {
1631 struct sock_fprog prog;
1632 pid_t tracer;
1633 long poked;
1634 struct tracer_args_poke_t tracer_args;
1635 };
1636
1637 FIXTURE_SETUP(TRACE_poke)
1638 {
1639 struct sock_filter filter[] = {
1640 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1641 offsetof(struct seccomp_data, nr)),
1642 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1643 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001),
1644 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1645 };
1646
1647 self->poked = 0;
1648 memset(&self->prog, 0, sizeof(self->prog));
1649 self->prog.filter = malloc(sizeof(filter));
1650 ASSERT_NE(NULL, self->prog.filter);
1651 memcpy(self->prog.filter, filter, sizeof(filter));
1652 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1653
1654 /* Set up tracer args. */
1655 self->tracer_args.poke_addr = (unsigned long)&self->poked;
1656
1657 /* Launch tracer. */
1658 self->tracer = setup_trace_fixture(_metadata, tracer_poke,
1659 &self->tracer_args, false);
1660 }
1661
1662 FIXTURE_TEARDOWN(TRACE_poke)
1663 {
1664 teardown_trace_fixture(_metadata, self->tracer);
1665 if (self->prog.filter)
1666 free(self->prog.filter);
1667 }
1668
1669 TEST_F(TRACE_poke, read_has_side_effects)
1670 {
1671 ssize_t ret;
1672
1673 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1674 ASSERT_EQ(0, ret);
1675
1676 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1677 ASSERT_EQ(0, ret);
1678
1679 EXPECT_EQ(0, self->poked);
1680 ret = read(-1, NULL, 0);
1681 EXPECT_EQ(-1, ret);
1682 EXPECT_EQ(0x1001, self->poked);
1683 }
1684
1685 TEST_F(TRACE_poke, getpid_runs_normally)
1686 {
1687 long ret;
1688
1689 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1690 ASSERT_EQ(0, ret);
1691
1692 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1693 ASSERT_EQ(0, ret);
1694
1695 EXPECT_EQ(0, self->poked);
1696 EXPECT_NE(0, syscall(__NR_getpid));
1697 EXPECT_EQ(0, self->poked);
1698 }
1699
1700 #if defined(__x86_64__)
1701 # define ARCH_REGS struct user_regs_struct
1702 # define SYSCALL_NUM(_regs) (_regs).orig_rax
1703 # define SYSCALL_RET(_regs) (_regs).rax
1704 #elif defined(__i386__)
1705 # define ARCH_REGS struct user_regs_struct
1706 # define SYSCALL_NUM(_regs) (_regs).orig_eax
1707 # define SYSCALL_RET(_regs) (_regs).eax
1708 #elif defined(__arm__)
1709 # define ARCH_REGS struct pt_regs
1710 # define SYSCALL_NUM(_regs) (_regs).ARM_r7
1711 # ifndef PTRACE_SET_SYSCALL
1712 # define PTRACE_SET_SYSCALL 23
1713 # endif
1714 # define SYSCALL_NUM_SET(_regs, _nr) \
1715 EXPECT_EQ(0, ptrace(PTRACE_SET_SYSCALL, tracee, NULL, _nr))
1716 # define SYSCALL_RET(_regs) (_regs).ARM_r0
1717 #elif defined(__aarch64__)
1718 # define ARCH_REGS struct user_pt_regs
1719 # define SYSCALL_NUM(_regs) (_regs).regs[8]
1720 # ifndef NT_ARM_SYSTEM_CALL
1721 # define NT_ARM_SYSTEM_CALL 0x404
1722 # endif
1723 # define SYSCALL_NUM_SET(_regs, _nr) \
1724 do { \
1725 struct iovec __v; \
1726 typeof(_nr) __nr = (_nr); \
1727 __v.iov_base = &__nr; \
1728 __v.iov_len = sizeof(__nr); \
1729 EXPECT_EQ(0, ptrace(PTRACE_SETREGSET, tracee, \
1730 NT_ARM_SYSTEM_CALL, &__v)); \
1731 } while (0)
1732 # define SYSCALL_RET(_regs) (_regs).regs[0]
1733 #elif defined(__riscv) && __riscv_xlen == 64
1734 # define ARCH_REGS struct user_regs_struct
1735 # define SYSCALL_NUM(_regs) (_regs).a7
1736 # define SYSCALL_RET(_regs) (_regs).a0
1737 #elif defined(__csky__)
1738 # define ARCH_REGS struct pt_regs
1739 # if defined(__CSKYABIV2__)
1740 # define SYSCALL_NUM(_regs) (_regs).regs[3]
1741 # else
1742 # define SYSCALL_NUM(_regs) (_regs).regs[9]
1743 # endif
1744 # define SYSCALL_RET(_regs) (_regs).a0
1745 #elif defined(__hppa__)
1746 # define ARCH_REGS struct user_regs_struct
1747 # define SYSCALL_NUM(_regs) (_regs).gr[20]
1748 # define SYSCALL_RET(_regs) (_regs).gr[28]
1749 #elif defined(__powerpc__)
1750 # define ARCH_REGS struct pt_regs
1751 # define SYSCALL_NUM(_regs) (_regs).gpr[0]
1752 # define SYSCALL_RET(_regs) (_regs).gpr[3]
1753 #elif defined(__s390__)
1754 # define ARCH_REGS s390_regs
1755 # define SYSCALL_NUM(_regs) (_regs).gprs[2]
1756 # define SYSCALL_RET(_regs) (_regs).gprs[2]
1757 # define SYSCALL_NUM_RET_SHARE_REG
1758 #elif defined(__mips__)
1759 # include <asm/unistd_nr_n32.h>
1760 # include <asm/unistd_nr_n64.h>
1761 # include <asm/unistd_nr_o32.h>
1762 # define ARCH_REGS struct pt_regs
1763 # define SYSCALL_NUM(_regs) \
1764 ({ \
1765 typeof((_regs).regs[2]) _nr; \
1766 if ((_regs).regs[2] == __NR_O32_Linux) \
1767 _nr = (_regs).regs[4]; \
1768 else \
1769 _nr = (_regs).regs[2]; \
1770 _nr; \
1771 })
1772 # define SYSCALL_NUM_SET(_regs, _nr) \
1773 do { \
1774 if ((_regs).regs[2] == __NR_O32_Linux) \
1775 (_regs).regs[4] = _nr; \
1776 else \
1777 (_regs).regs[2] = _nr; \
1778 } while (0)
1779 # define SYSCALL_RET(_regs) (_regs).regs[2]
1780 # define SYSCALL_NUM_RET_SHARE_REG
1781 #elif defined(__xtensa__)
1782 # define ARCH_REGS struct user_pt_regs
1783 # define SYSCALL_NUM(_regs) (_regs).syscall
1784 /*
1785 * On xtensa syscall return value is in the register
1786 * a2 of the current window which is not fixed.
1787 */
1788 #define SYSCALL_RET(_regs) (_regs).a[(_regs).windowbase * 4 + 2]
1789 #elif defined(__sh__)
1790 # define ARCH_REGS struct pt_regs
1791 # define SYSCALL_NUM(_regs) (_regs).gpr[3]
1792 # define SYSCALL_RET(_regs) (_regs).gpr[0]
1793 #else
1794 # error "Do not know how to find your architecture's registers and syscalls"
1795 #endif
1796
1797 /*
1798 * Most architectures can change the syscall by just updating the
1799 * associated register. This is the default if not defined above.
1800 */
1801 #ifndef SYSCALL_NUM_SET
1802 # define SYSCALL_NUM_SET(_regs, _nr) \
1803 do { \
1804 SYSCALL_NUM(_regs) = (_nr); \
1805 } while (0)
1806 #endif
1807
1808 /* When the syscall return can't be changed, stub out the tests for it. */
1809 #ifdef SYSCALL_NUM_RET_SHARE_REG
1810 # define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(-1, action)
1811 #else
1812 # define EXPECT_SYSCALL_RETURN(val, action) \
1813 do { \
1814 errno = 0; \
1815 if (val < 0) { \
1816 EXPECT_EQ(-1, action); \
1817 EXPECT_EQ(-(val), errno); \
1818 } else { \
1819 EXPECT_EQ(val, action); \
1820 } \
1821 } while (0)
1822 #endif
1823
1824 /* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1825 * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1826 */
1827 #if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
1828 #define HAVE_GETREGS
1829 #endif
1830
1831 /* Architecture-specific syscall fetching routine. */
1832 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1833 {
1834 ARCH_REGS regs;
1835 #ifdef HAVE_GETREGS
1836 EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
1837 TH_LOG("PTRACE_GETREGS failed");
1838 return -1;
1839 }
1840 #else
1841 struct iovec iov;
1842
1843 iov.iov_base = &regs;
1844 iov.iov_len = sizeof(regs);
1845 EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1846 TH_LOG("PTRACE_GETREGSET failed");
1847 return -1;
1848 }
1849 #endif
1850
1851 return SYSCALL_NUM(regs);
1852 }
1853
1854 /* Architecture-specific syscall changing routine. */
1855 void change_syscall(struct __test_metadata *_metadata,
1856 pid_t tracee, int syscall, int result)
1857 {
1858 int ret;
1859 ARCH_REGS regs;
1860 #ifdef HAVE_GETREGS
1861 ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
1862 #else
1863 struct iovec iov;
1864 iov.iov_base = &regs;
1865 iov.iov_len = sizeof(regs);
1866 ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
1867 #endif
1868 EXPECT_EQ(0, ret);
1869
1870 SYSCALL_NUM_SET(regs, syscall);
1871
1872 /* If syscall is skipped, change return value. */
1873 if (syscall == -1)
1874 #ifdef SYSCALL_NUM_RET_SHARE_REG
1875 TH_LOG("Can't modify syscall return on this architecture");
1876 #else
1877 SYSCALL_RET(regs) = result;
1878 #endif
1879
1880 /* Flush any register changes made. */
1881 #ifdef HAVE_GETREGS
1882 ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
1883 #else
1884 iov.iov_base = &regs;
1885 iov.iov_len = sizeof(regs);
1886 ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
1887 #endif
1888 EXPECT_EQ(0, ret);
1889 }
1890
1891 void tracer_seccomp(struct __test_metadata *_metadata, pid_t tracee,
1892 int status, void *args)
1893 {
1894 int ret;
1895 unsigned long msg;
1896
1897 /* Make sure we got the right message. */
1898 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1899 EXPECT_EQ(0, ret);
1900
1901 /* Validate and take action on expected syscalls. */
1902 switch (msg) {
1903 case 0x1002:
1904 /* change getpid to getppid. */
1905 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
1906 change_syscall(_metadata, tracee, __NR_getppid, 0);
1907 break;
1908 case 0x1003:
1909 /* skip gettid with valid return code. */
1910 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
1911 change_syscall(_metadata, tracee, -1, 45000);
1912 break;
1913 case 0x1004:
1914 /* skip openat with error. */
1915 EXPECT_EQ(__NR_openat, get_syscall(_metadata, tracee));
1916 change_syscall(_metadata, tracee, -1, -ESRCH);
1917 break;
1918 case 0x1005:
1919 /* do nothing (allow getppid) */
1920 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
1921 break;
1922 default:
1923 EXPECT_EQ(0, msg) {
1924 TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1925 kill(tracee, SIGKILL);
1926 }
1927 }
1928
1929 }
1930
1931 void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
1932 int status, void *args)
1933 {
1934 int ret, nr;
1935 unsigned long msg;
1936 static bool entry;
1937
1938 /*
1939 * The traditional way to tell PTRACE_SYSCALL entry/exit
1940 * is by counting.
1941 */
1942 entry = !entry;
1943
1944 /* Make sure we got an appropriate message. */
1945 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1946 EXPECT_EQ(0, ret);
1947 EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
1948 : PTRACE_EVENTMSG_SYSCALL_EXIT, msg);
1949
1950 if (!entry)
1951 return;
1952
1953 nr = get_syscall(_metadata, tracee);
1954
1955 if (nr == __NR_getpid)
1956 change_syscall(_metadata, tracee, __NR_getppid, 0);
1957 if (nr == __NR_gettid)
1958 change_syscall(_metadata, tracee, -1, 45000);
1959 if (nr == __NR_openat)
1960 change_syscall(_metadata, tracee, -1, -ESRCH);
1961 }
1962
1963 FIXTURE(TRACE_syscall) {
1964 struct sock_fprog prog;
1965 pid_t tracer, mytid, mypid, parent;
1966 };
1967
1968 FIXTURE_VARIANT(TRACE_syscall) {
1969 /*
1970 * All of the SECCOMP_RET_TRACE behaviors can be tested with either
1971 * SECCOMP_RET_TRACE+PTRACE_CONT or plain ptrace()+PTRACE_SYSCALL.
1972 * This indicates if we should use SECCOMP_RET_TRACE (false), or
1973 * ptrace (true).
1974 */
1975 bool use_ptrace;
1976 };
1977
1978 FIXTURE_VARIANT_ADD(TRACE_syscall, ptrace) {
1979 .use_ptrace = true,
1980 };
1981
1982 FIXTURE_VARIANT_ADD(TRACE_syscall, seccomp) {
1983 .use_ptrace = false,
1984 };
1985
1986 FIXTURE_SETUP(TRACE_syscall)
1987 {
1988 struct sock_filter filter[] = {
1989 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1990 offsetof(struct seccomp_data, nr)),
1991 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1992 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1993 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1994 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
1995 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_openat, 0, 1),
1996 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
1997 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1998 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1005),
1999 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2000 };
2001 struct sock_fprog prog = {
2002 .len = (unsigned short)ARRAY_SIZE(filter),
2003 .filter = filter,
2004 };
2005 long ret;
2006
2007 /* Prepare some testable syscall results. */
2008 self->mytid = syscall(__NR_gettid);
2009 ASSERT_GT(self->mytid, 0);
2010 ASSERT_NE(self->mytid, 1) {
2011 TH_LOG("Running this test as init is not supported. :)");
2012 }
2013
2014 self->mypid = getpid();
2015 ASSERT_GT(self->mypid, 0);
2016 ASSERT_EQ(self->mytid, self->mypid);
2017
2018 self->parent = getppid();
2019 ASSERT_GT(self->parent, 0);
2020 ASSERT_NE(self->parent, self->mypid);
2021
2022 /* Launch tracer. */
2023 self->tracer = setup_trace_fixture(_metadata,
2024 variant->use_ptrace ? tracer_ptrace
2025 : tracer_seccomp,
2026 NULL, variant->use_ptrace);
2027
2028 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2029 ASSERT_EQ(0, ret);
2030
2031 if (variant->use_ptrace)
2032 return;
2033
2034 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2035 ASSERT_EQ(0, ret);
2036 }
2037
2038 FIXTURE_TEARDOWN(TRACE_syscall)
2039 {
2040 teardown_trace_fixture(_metadata, self->tracer);
2041 }
2042
2043 TEST(negative_ENOSYS)
2044 {
2045 /*
2046 * There should be no difference between an "internal" skip
2047 * and userspace asking for syscall "-1".
2048 */
2049 errno = 0;
2050 EXPECT_EQ(-1, syscall(-1));
2051 EXPECT_EQ(errno, ENOSYS);
2052 /* And no difference for "still not valid but not -1". */
2053 errno = 0;
2054 EXPECT_EQ(-1, syscall(-101));
2055 EXPECT_EQ(errno, ENOSYS);
2056 }
2057
2058 TEST_F(TRACE_syscall, negative_ENOSYS)
2059 {
2060 negative_ENOSYS(_metadata);
2061 }
2062
2063 TEST_F(TRACE_syscall, syscall_allowed)
2064 {
2065 /* getppid works as expected (no changes). */
2066 EXPECT_EQ(self->parent, syscall(__NR_getppid));
2067 EXPECT_NE(self->mypid, syscall(__NR_getppid));
2068 }
2069
2070 TEST_F(TRACE_syscall, syscall_redirected)
2071 {
2072 /* getpid has been redirected to getppid as expected. */
2073 EXPECT_EQ(self->parent, syscall(__NR_getpid));
2074 EXPECT_NE(self->mypid, syscall(__NR_getpid));
2075 }
2076
2077 TEST_F(TRACE_syscall, syscall_errno)
2078 {
2079 /* Tracer should skip the open syscall, resulting in ESRCH. */
2080 EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
2081 }
2082
2083 TEST_F(TRACE_syscall, syscall_faked)
2084 {
2085 /* Tracer skips the gettid syscall and store altered return value. */
2086 EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
2087 }
2088
2089 TEST_F(TRACE_syscall, skip_after)
2090 {
2091 struct sock_filter filter[] = {
2092 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2093 offsetof(struct seccomp_data, nr)),
2094 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2095 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
2096 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2097 };
2098 struct sock_fprog prog = {
2099 .len = (unsigned short)ARRAY_SIZE(filter),
2100 .filter = filter,
2101 };
2102 long ret;
2103
2104 /* Install additional "errno on getppid" filter. */
2105 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2106 ASSERT_EQ(0, ret);
2107
2108 /* Tracer will redirect getpid to getppid, and we should see EPERM. */
2109 errno = 0;
2110 EXPECT_EQ(-1, syscall(__NR_getpid));
2111 EXPECT_EQ(EPERM, errno);
2112 }
2113
2114 TEST_F_SIGNAL(TRACE_syscall, kill_after, SIGSYS)
2115 {
2116 struct sock_filter filter[] = {
2117 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2118 offsetof(struct seccomp_data, nr)),
2119 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2120 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2121 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2122 };
2123 struct sock_fprog prog = {
2124 .len = (unsigned short)ARRAY_SIZE(filter),
2125 .filter = filter,
2126 };
2127 long ret;
2128
2129 /* Install additional "death on getppid" filter. */
2130 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2131 ASSERT_EQ(0, ret);
2132
2133 /* Tracer will redirect getpid to getppid, and we should die. */
2134 EXPECT_NE(self->mypid, syscall(__NR_getpid));
2135 }
2136
2137 TEST(seccomp_syscall)
2138 {
2139 struct sock_filter filter[] = {
2140 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2141 };
2142 struct sock_fprog prog = {
2143 .len = (unsigned short)ARRAY_SIZE(filter),
2144 .filter = filter,
2145 };
2146 long ret;
2147
2148 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2149 ASSERT_EQ(0, ret) {
2150 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2151 }
2152
2153 /* Reject insane operation. */
2154 ret = seccomp(-1, 0, &prog);
2155 ASSERT_NE(ENOSYS, errno) {
2156 TH_LOG("Kernel does not support seccomp syscall!");
2157 }
2158 EXPECT_EQ(EINVAL, errno) {
2159 TH_LOG("Did not reject crazy op value!");
2160 }
2161
2162 /* Reject strict with flags or pointer. */
2163 ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
2164 EXPECT_EQ(EINVAL, errno) {
2165 TH_LOG("Did not reject mode strict with flags!");
2166 }
2167 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
2168 EXPECT_EQ(EINVAL, errno) {
2169 TH_LOG("Did not reject mode strict with uargs!");
2170 }
2171
2172 /* Reject insane args for filter. */
2173 ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
2174 EXPECT_EQ(EINVAL, errno) {
2175 TH_LOG("Did not reject crazy filter flags!");
2176 }
2177 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
2178 EXPECT_EQ(EFAULT, errno) {
2179 TH_LOG("Did not reject NULL filter!");
2180 }
2181
2182 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2183 EXPECT_EQ(0, errno) {
2184 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
2185 strerror(errno));
2186 }
2187 }
2188
2189 TEST(seccomp_syscall_mode_lock)
2190 {
2191 struct sock_filter filter[] = {
2192 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2193 };
2194 struct sock_fprog prog = {
2195 .len = (unsigned short)ARRAY_SIZE(filter),
2196 .filter = filter,
2197 };
2198 long ret;
2199
2200 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2201 ASSERT_EQ(0, ret) {
2202 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2203 }
2204
2205 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2206 ASSERT_NE(ENOSYS, errno) {
2207 TH_LOG("Kernel does not support seccomp syscall!");
2208 }
2209 EXPECT_EQ(0, ret) {
2210 TH_LOG("Could not install filter!");
2211 }
2212
2213 /* Make sure neither entry point will switch to strict. */
2214 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
2215 EXPECT_EQ(EINVAL, errno) {
2216 TH_LOG("Switched to mode strict!");
2217 }
2218
2219 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
2220 EXPECT_EQ(EINVAL, errno) {
2221 TH_LOG("Switched to mode strict!");
2222 }
2223 }
2224
2225 /*
2226 * Test detection of known and unknown filter flags. Userspace needs to be able
2227 * to check if a filter flag is supported by the current kernel and a good way
2228 * of doing that is by attempting to enter filter mode, with the flag bit in
2229 * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
2230 * that the flag is valid and EINVAL indicates that the flag is invalid.
2231 */
2232 TEST(detect_seccomp_filter_flags)
2233 {
2234 unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
2235 SECCOMP_FILTER_FLAG_LOG,
2236 SECCOMP_FILTER_FLAG_SPEC_ALLOW,
2237 SECCOMP_FILTER_FLAG_NEW_LISTENER,
2238 SECCOMP_FILTER_FLAG_TSYNC_ESRCH };
2239 unsigned int exclusive[] = {
2240 SECCOMP_FILTER_FLAG_TSYNC,
2241 SECCOMP_FILTER_FLAG_NEW_LISTENER };
2242 unsigned int flag, all_flags, exclusive_mask;
2243 int i;
2244 long ret;
2245
2246 /* Test detection of individual known-good filter flags */
2247 for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
2248 int bits = 0;
2249
2250 flag = flags[i];
2251 /* Make sure the flag is a single bit! */
2252 while (flag) {
2253 if (flag & 0x1)
2254 bits ++;
2255 flag >>= 1;
2256 }
2257 ASSERT_EQ(1, bits);
2258 flag = flags[i];
2259
2260 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2261 ASSERT_NE(ENOSYS, errno) {
2262 TH_LOG("Kernel does not support seccomp syscall!");
2263 }
2264 EXPECT_EQ(-1, ret);
2265 EXPECT_EQ(EFAULT, errno) {
2266 TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
2267 flag);
2268 }
2269
2270 all_flags |= flag;
2271 }
2272
2273 /*
2274 * Test detection of all known-good filter flags combined. But
2275 * for the exclusive flags we need to mask them out and try them
2276 * individually for the "all flags" testing.
2277 */
2278 exclusive_mask = 0;
2279 for (i = 0; i < ARRAY_SIZE(exclusive); i++)
2280 exclusive_mask |= exclusive[i];
2281 for (i = 0; i < ARRAY_SIZE(exclusive); i++) {
2282 flag = all_flags & ~exclusive_mask;
2283 flag |= exclusive[i];
2284
2285 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2286 EXPECT_EQ(-1, ret);
2287 EXPECT_EQ(EFAULT, errno) {
2288 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
2289 flag);
2290 }
2291 }
2292
2293 /* Test detection of an unknown filter flags, without exclusives. */
2294 flag = -1;
2295 flag &= ~exclusive_mask;
2296 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2297 EXPECT_EQ(-1, ret);
2298 EXPECT_EQ(EINVAL, errno) {
2299 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
2300 flag);
2301 }
2302
2303 /*
2304 * Test detection of an unknown filter flag that may simply need to be
2305 * added to this test
2306 */
2307 flag = flags[ARRAY_SIZE(flags) - 1] << 1;
2308 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2309 EXPECT_EQ(-1, ret);
2310 EXPECT_EQ(EINVAL, errno) {
2311 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?",
2312 flag);
2313 }
2314 }
2315
2316 TEST(TSYNC_first)
2317 {
2318 struct sock_filter filter[] = {
2319 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2320 };
2321 struct sock_fprog prog = {
2322 .len = (unsigned short)ARRAY_SIZE(filter),
2323 .filter = filter,
2324 };
2325 long ret;
2326
2327 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2328 ASSERT_EQ(0, ret) {
2329 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2330 }
2331
2332 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2333 &prog);
2334 ASSERT_NE(ENOSYS, errno) {
2335 TH_LOG("Kernel does not support seccomp syscall!");
2336 }
2337 EXPECT_EQ(0, ret) {
2338 TH_LOG("Could not install initial filter with TSYNC!");
2339 }
2340 }
2341
2342 #define TSYNC_SIBLINGS 2
2343 struct tsync_sibling {
2344 pthread_t tid;
2345 pid_t system_tid;
2346 sem_t *started;
2347 pthread_cond_t *cond;
2348 pthread_mutex_t *mutex;
2349 int diverge;
2350 int num_waits;
2351 struct sock_fprog *prog;
2352 struct __test_metadata *metadata;
2353 };
2354
2355 /*
2356 * To avoid joining joined threads (which is not allowed by Bionic),
2357 * make sure we both successfully join and clear the tid to skip a
2358 * later join attempt during fixture teardown. Any remaining threads
2359 * will be directly killed during teardown.
2360 */
2361 #define PTHREAD_JOIN(tid, status) \
2362 do { \
2363 int _rc = pthread_join(tid, status); \
2364 if (_rc) { \
2365 TH_LOG("pthread_join of tid %u failed: %d\n", \
2366 (unsigned int)tid, _rc); \
2367 } else { \
2368 tid = 0; \
2369 } \
2370 } while (0)
2371
2372 FIXTURE(TSYNC) {
2373 struct sock_fprog root_prog, apply_prog;
2374 struct tsync_sibling sibling[TSYNC_SIBLINGS];
2375 sem_t started;
2376 pthread_cond_t cond;
2377 pthread_mutex_t mutex;
2378 int sibling_count;
2379 };
2380
2381 FIXTURE_SETUP(TSYNC)
2382 {
2383 struct sock_filter root_filter[] = {
2384 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2385 };
2386 struct sock_filter apply_filter[] = {
2387 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2388 offsetof(struct seccomp_data, nr)),
2389 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
2390 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2391 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2392 };
2393
2394 memset(&self->root_prog, 0, sizeof(self->root_prog));
2395 memset(&self->apply_prog, 0, sizeof(self->apply_prog));
2396 memset(&self->sibling, 0, sizeof(self->sibling));
2397 self->root_prog.filter = malloc(sizeof(root_filter));
2398 ASSERT_NE(NULL, self->root_prog.filter);
2399 memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
2400 self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
2401
2402 self->apply_prog.filter = malloc(sizeof(apply_filter));
2403 ASSERT_NE(NULL, self->apply_prog.filter);
2404 memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
2405 self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
2406
2407 self->sibling_count = 0;
2408 pthread_mutex_init(&self->mutex, NULL);
2409 pthread_cond_init(&self->cond, NULL);
2410 sem_init(&self->started, 0, 0);
2411 self->sibling[0].tid = 0;
2412 self->sibling[0].cond = &self->cond;
2413 self->sibling[0].started = &self->started;
2414 self->sibling[0].mutex = &self->mutex;
2415 self->sibling[0].diverge = 0;
2416 self->sibling[0].num_waits = 1;
2417 self->sibling[0].prog = &self->root_prog;
2418 self->sibling[0].metadata = _metadata;
2419 self->sibling[1].tid = 0;
2420 self->sibling[1].cond = &self->cond;
2421 self->sibling[1].started = &self->started;
2422 self->sibling[1].mutex = &self->mutex;
2423 self->sibling[1].diverge = 0;
2424 self->sibling[1].prog = &self->root_prog;
2425 self->sibling[1].num_waits = 1;
2426 self->sibling[1].metadata = _metadata;
2427 }
2428
2429 FIXTURE_TEARDOWN(TSYNC)
2430 {
2431 int sib = 0;
2432
2433 if (self->root_prog.filter)
2434 free(self->root_prog.filter);
2435 if (self->apply_prog.filter)
2436 free(self->apply_prog.filter);
2437
2438 for ( ; sib < self->sibling_count; ++sib) {
2439 struct tsync_sibling *s = &self->sibling[sib];
2440
2441 if (!s->tid)
2442 continue;
2443 /*
2444 * If a thread is still running, it may be stuck, so hit
2445 * it over the head really hard.
2446 */
2447 pthread_kill(s->tid, 9);
2448 }
2449 pthread_mutex_destroy(&self->mutex);
2450 pthread_cond_destroy(&self->cond);
2451 sem_destroy(&self->started);
2452 }
2453
2454 void *tsync_sibling(void *data)
2455 {
2456 long ret = 0;
2457 struct tsync_sibling *me = data;
2458
2459 me->system_tid = syscall(__NR_gettid);
2460
2461 pthread_mutex_lock(me->mutex);
2462 if (me->diverge) {
2463 /* Just re-apply the root prog to fork the tree */
2464 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
2465 me->prog, 0, 0);
2466 }
2467 sem_post(me->started);
2468 /* Return outside of started so parent notices failures. */
2469 if (ret) {
2470 pthread_mutex_unlock(me->mutex);
2471 return (void *)SIBLING_EXIT_FAILURE;
2472 }
2473 do {
2474 pthread_cond_wait(me->cond, me->mutex);
2475 me->num_waits = me->num_waits - 1;
2476 } while (me->num_waits);
2477 pthread_mutex_unlock(me->mutex);
2478
2479 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
2480 if (!ret)
2481 return (void *)SIBLING_EXIT_NEWPRIVS;
2482 read(0, NULL, 0);
2483 return (void *)SIBLING_EXIT_UNKILLED;
2484 }
2485
2486 void tsync_start_sibling(struct tsync_sibling *sibling)
2487 {
2488 pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
2489 }
2490
2491 TEST_F(TSYNC, siblings_fail_prctl)
2492 {
2493 long ret;
2494 void *status;
2495 struct sock_filter filter[] = {
2496 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2497 offsetof(struct seccomp_data, nr)),
2498 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
2499 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
2500 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2501 };
2502 struct sock_fprog prog = {
2503 .len = (unsigned short)ARRAY_SIZE(filter),
2504 .filter = filter,
2505 };
2506
2507 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2508 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2509 }
2510
2511 /* Check prctl failure detection by requesting sib 0 diverge. */
2512 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2513 ASSERT_NE(ENOSYS, errno) {
2514 TH_LOG("Kernel does not support seccomp syscall!");
2515 }
2516 ASSERT_EQ(0, ret) {
2517 TH_LOG("setting filter failed");
2518 }
2519
2520 self->sibling[0].diverge = 1;
2521 tsync_start_sibling(&self->sibling[0]);
2522 tsync_start_sibling(&self->sibling[1]);
2523
2524 while (self->sibling_count < TSYNC_SIBLINGS) {
2525 sem_wait(&self->started);
2526 self->sibling_count++;
2527 }
2528
2529 /* Signal the threads to clean up*/
2530 pthread_mutex_lock(&self->mutex);
2531 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2532 TH_LOG("cond broadcast non-zero");
2533 }
2534 pthread_mutex_unlock(&self->mutex);
2535
2536 /* Ensure diverging sibling failed to call prctl. */
2537 PTHREAD_JOIN(self->sibling[0].tid, &status);
2538 EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
2539 PTHREAD_JOIN(self->sibling[1].tid, &status);
2540 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2541 }
2542
2543 TEST_F(TSYNC, two_siblings_with_ancestor)
2544 {
2545 long ret;
2546 void *status;
2547
2548 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2549 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2550 }
2551
2552 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2553 ASSERT_NE(ENOSYS, errno) {
2554 TH_LOG("Kernel does not support seccomp syscall!");
2555 }
2556 ASSERT_EQ(0, ret) {
2557 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2558 }
2559 tsync_start_sibling(&self->sibling[0]);
2560 tsync_start_sibling(&self->sibling[1]);
2561
2562 while (self->sibling_count < TSYNC_SIBLINGS) {
2563 sem_wait(&self->started);
2564 self->sibling_count++;
2565 }
2566
2567 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2568 &self->apply_prog);
2569 ASSERT_EQ(0, ret) {
2570 TH_LOG("Could install filter on all threads!");
2571 }
2572 /* Tell the siblings to test the policy */
2573 pthread_mutex_lock(&self->mutex);
2574 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2575 TH_LOG("cond broadcast non-zero");
2576 }
2577 pthread_mutex_unlock(&self->mutex);
2578 /* Ensure they are both killed and don't exit cleanly. */
2579 PTHREAD_JOIN(self->sibling[0].tid, &status);
2580 EXPECT_EQ(0x0, (long)status);
2581 PTHREAD_JOIN(self->sibling[1].tid, &status);
2582 EXPECT_EQ(0x0, (long)status);
2583 }
2584
2585 TEST_F(TSYNC, two_sibling_want_nnp)
2586 {
2587 void *status;
2588
2589 /* start siblings before any prctl() operations */
2590 tsync_start_sibling(&self->sibling[0]);
2591 tsync_start_sibling(&self->sibling[1]);
2592 while (self->sibling_count < TSYNC_SIBLINGS) {
2593 sem_wait(&self->started);
2594 self->sibling_count++;
2595 }
2596
2597 /* Tell the siblings to test no policy */
2598 pthread_mutex_lock(&self->mutex);
2599 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2600 TH_LOG("cond broadcast non-zero");
2601 }
2602 pthread_mutex_unlock(&self->mutex);
2603
2604 /* Ensure they are both upset about lacking nnp. */
2605 PTHREAD_JOIN(self->sibling[0].tid, &status);
2606 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2607 PTHREAD_JOIN(self->sibling[1].tid, &status);
2608 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2609 }
2610
2611 TEST_F(TSYNC, two_siblings_with_no_filter)
2612 {
2613 long ret;
2614 void *status;
2615
2616 /* start siblings before any prctl() operations */
2617 tsync_start_sibling(&self->sibling[0]);
2618 tsync_start_sibling(&self->sibling[1]);
2619 while (self->sibling_count < TSYNC_SIBLINGS) {
2620 sem_wait(&self->started);
2621 self->sibling_count++;
2622 }
2623
2624 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2625 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2626 }
2627
2628 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2629 &self->apply_prog);
2630 ASSERT_NE(ENOSYS, errno) {
2631 TH_LOG("Kernel does not support seccomp syscall!");
2632 }
2633 ASSERT_EQ(0, ret) {
2634 TH_LOG("Could install filter on all threads!");
2635 }
2636
2637 /* Tell the siblings to test the policy */
2638 pthread_mutex_lock(&self->mutex);
2639 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2640 TH_LOG("cond broadcast non-zero");
2641 }
2642 pthread_mutex_unlock(&self->mutex);
2643
2644 /* Ensure they are both killed and don't exit cleanly. */
2645 PTHREAD_JOIN(self->sibling[0].tid, &status);
2646 EXPECT_EQ(0x0, (long)status);
2647 PTHREAD_JOIN(self->sibling[1].tid, &status);
2648 EXPECT_EQ(0x0, (long)status);
2649 }
2650
2651 TEST_F(TSYNC, two_siblings_with_one_divergence)
2652 {
2653 long ret;
2654 void *status;
2655
2656 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2657 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2658 }
2659
2660 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2661 ASSERT_NE(ENOSYS, errno) {
2662 TH_LOG("Kernel does not support seccomp syscall!");
2663 }
2664 ASSERT_EQ(0, ret) {
2665 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2666 }
2667 self->sibling[0].diverge = 1;
2668 tsync_start_sibling(&self->sibling[0]);
2669 tsync_start_sibling(&self->sibling[1]);
2670
2671 while (self->sibling_count < TSYNC_SIBLINGS) {
2672 sem_wait(&self->started);
2673 self->sibling_count++;
2674 }
2675
2676 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2677 &self->apply_prog);
2678 ASSERT_EQ(self->sibling[0].system_tid, ret) {
2679 TH_LOG("Did not fail on diverged sibling.");
2680 }
2681
2682 /* Wake the threads */
2683 pthread_mutex_lock(&self->mutex);
2684 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2685 TH_LOG("cond broadcast non-zero");
2686 }
2687 pthread_mutex_unlock(&self->mutex);
2688
2689 /* Ensure they are both unkilled. */
2690 PTHREAD_JOIN(self->sibling[0].tid, &status);
2691 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2692 PTHREAD_JOIN(self->sibling[1].tid, &status);
2693 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2694 }
2695
2696 TEST_F(TSYNC, two_siblings_with_one_divergence_no_tid_in_err)
2697 {
2698 long ret, flags;
2699 void *status;
2700
2701 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2702 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2703 }
2704
2705 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2706 ASSERT_NE(ENOSYS, errno) {
2707 TH_LOG("Kernel does not support seccomp syscall!");
2708 }
2709 ASSERT_EQ(0, ret) {
2710 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2711 }
2712 self->sibling[0].diverge = 1;
2713 tsync_start_sibling(&self->sibling[0]);
2714 tsync_start_sibling(&self->sibling[1]);
2715
2716 while (self->sibling_count < TSYNC_SIBLINGS) {
2717 sem_wait(&self->started);
2718 self->sibling_count++;
2719 }
2720
2721 flags = SECCOMP_FILTER_FLAG_TSYNC | \
2722 SECCOMP_FILTER_FLAG_TSYNC_ESRCH;
2723 ret = seccomp(SECCOMP_SET_MODE_FILTER, flags, &self->apply_prog);
2724 ASSERT_EQ(ESRCH, errno) {
2725 TH_LOG("Did not return ESRCH for diverged sibling.");
2726 }
2727 ASSERT_EQ(-1, ret) {
2728 TH_LOG("Did not fail on diverged sibling.");
2729 }
2730
2731 /* Wake the threads */
2732 pthread_mutex_lock(&self->mutex);
2733 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2734 TH_LOG("cond broadcast non-zero");
2735 }
2736 pthread_mutex_unlock(&self->mutex);
2737
2738 /* Ensure they are both unkilled. */
2739 PTHREAD_JOIN(self->sibling[0].tid, &status);
2740 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2741 PTHREAD_JOIN(self->sibling[1].tid, &status);
2742 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2743 }
2744
2745 TEST_F(TSYNC, two_siblings_not_under_filter)
2746 {
2747 long ret, sib;
2748 void *status;
2749 struct timespec delay = { .tv_nsec = 100000000 };
2750
2751 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2752 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2753 }
2754
2755 /*
2756 * Sibling 0 will have its own seccomp policy
2757 * and Sibling 1 will not be under seccomp at
2758 * all. Sibling 1 will enter seccomp and 0
2759 * will cause failure.
2760 */
2761 self->sibling[0].diverge = 1;
2762 tsync_start_sibling(&self->sibling[0]);
2763 tsync_start_sibling(&self->sibling[1]);
2764
2765 while (self->sibling_count < TSYNC_SIBLINGS) {
2766 sem_wait(&self->started);
2767 self->sibling_count++;
2768 }
2769
2770 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2771 ASSERT_NE(ENOSYS, errno) {
2772 TH_LOG("Kernel does not support seccomp syscall!");
2773 }
2774 ASSERT_EQ(0, ret) {
2775 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2776 }
2777
2778 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2779 &self->apply_prog);
2780 ASSERT_EQ(ret, self->sibling[0].system_tid) {
2781 TH_LOG("Did not fail on diverged sibling.");
2782 }
2783 sib = 1;
2784 if (ret == self->sibling[0].system_tid)
2785 sib = 0;
2786
2787 pthread_mutex_lock(&self->mutex);
2788
2789 /* Increment the other siblings num_waits so we can clean up
2790 * the one we just saw.
2791 */
2792 self->sibling[!sib].num_waits += 1;
2793
2794 /* Signal the thread to clean up*/
2795 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2796 TH_LOG("cond broadcast non-zero");
2797 }
2798 pthread_mutex_unlock(&self->mutex);
2799 PTHREAD_JOIN(self->sibling[sib].tid, &status);
2800 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2801 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2802 while (!kill(self->sibling[sib].system_tid, 0))
2803 nanosleep(&delay, NULL);
2804 /* Switch to the remaining sibling */
2805 sib = !sib;
2806
2807 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2808 &self->apply_prog);
2809 ASSERT_EQ(0, ret) {
2810 TH_LOG("Expected the remaining sibling to sync");
2811 };
2812
2813 pthread_mutex_lock(&self->mutex);
2814
2815 /* If remaining sibling didn't have a chance to wake up during
2816 * the first broadcast, manually reduce the num_waits now.
2817 */
2818 if (self->sibling[sib].num_waits > 1)
2819 self->sibling[sib].num_waits = 1;
2820 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2821 TH_LOG("cond broadcast non-zero");
2822 }
2823 pthread_mutex_unlock(&self->mutex);
2824 PTHREAD_JOIN(self->sibling[sib].tid, &status);
2825 EXPECT_EQ(0, (long)status);
2826 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2827 while (!kill(self->sibling[sib].system_tid, 0))
2828 nanosleep(&delay, NULL);
2829
2830 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2831 &self->apply_prog);
2832 ASSERT_EQ(0, ret); /* just us chickens */
2833 }
2834
2835 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
2836 TEST(syscall_restart)
2837 {
2838 long ret;
2839 unsigned long msg;
2840 pid_t child_pid;
2841 int pipefd[2];
2842 int status;
2843 siginfo_t info = { };
2844 struct sock_filter filter[] = {
2845 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2846 offsetof(struct seccomp_data, nr)),
2847
2848 #ifdef __NR_sigreturn
2849 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 7, 0),
2850 #endif
2851 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 6, 0),
2852 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 5, 0),
2853 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 4, 0),
2854 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 5, 0),
2855 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_clock_nanosleep, 4, 0),
2856 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2857
2858 /* Allow __NR_write for easy logging. */
2859 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2860 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2861 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2862 /* The nanosleep jump target. */
2863 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2864 /* The restart_syscall jump target. */
2865 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
2866 };
2867 struct sock_fprog prog = {
2868 .len = (unsigned short)ARRAY_SIZE(filter),
2869 .filter = filter,
2870 };
2871 #if defined(__arm__)
2872 struct utsname utsbuf;
2873 #endif
2874
2875 ASSERT_EQ(0, pipe(pipefd));
2876
2877 child_pid = fork();
2878 ASSERT_LE(0, child_pid);
2879 if (child_pid == 0) {
2880 /* Child uses EXPECT not ASSERT to deliver status correctly. */
2881 char buf = ' ';
2882 struct timespec timeout = { };
2883
2884 /* Attach parent as tracer and stop. */
2885 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2886 EXPECT_EQ(0, raise(SIGSTOP));
2887
2888 EXPECT_EQ(0, close(pipefd[1]));
2889
2890 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2891 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2892 }
2893
2894 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2895 EXPECT_EQ(0, ret) {
2896 TH_LOG("Failed to install filter!");
2897 }
2898
2899 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2900 TH_LOG("Failed to read() sync from parent");
2901 }
2902 EXPECT_EQ('.', buf) {
2903 TH_LOG("Failed to get sync data from read()");
2904 }
2905
2906 /* Start nanosleep to be interrupted. */
2907 timeout.tv_sec = 1;
2908 errno = 0;
2909 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2910 TH_LOG("Call to nanosleep() failed (errno %d)", errno);
2911 }
2912
2913 /* Read final sync from parent. */
2914 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2915 TH_LOG("Failed final read() from parent");
2916 }
2917 EXPECT_EQ('!', buf) {
2918 TH_LOG("Failed to get final data from read()");
2919 }
2920
2921 /* Directly report the status of our test harness results. */
2922 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2923 : EXIT_FAILURE);
2924 }
2925 EXPECT_EQ(0, close(pipefd[0]));
2926
2927 /* Attach to child, setup options, and release. */
2928 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2929 ASSERT_EQ(true, WIFSTOPPED(status));
2930 ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2931 PTRACE_O_TRACESECCOMP));
2932 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2933 ASSERT_EQ(1, write(pipefd[1], ".", 1));
2934
2935 /* Wait for nanosleep() to start. */
2936 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2937 ASSERT_EQ(true, WIFSTOPPED(status));
2938 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2939 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2940 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2941 ASSERT_EQ(0x100, msg);
2942 ret = get_syscall(_metadata, child_pid);
2943 EXPECT_TRUE(ret == __NR_nanosleep || ret == __NR_clock_nanosleep);
2944
2945 /* Might as well check siginfo for sanity while we're here. */
2946 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2947 ASSERT_EQ(SIGTRAP, info.si_signo);
2948 ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2949 EXPECT_EQ(0, info.si_errno);
2950 EXPECT_EQ(getuid(), info.si_uid);
2951 /* Verify signal delivery came from child (seccomp-triggered). */
2952 EXPECT_EQ(child_pid, info.si_pid);
2953
2954 /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
2955 ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2956 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2957 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2958 ASSERT_EQ(true, WIFSTOPPED(status));
2959 ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
2960 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2961 /*
2962 * There is no siginfo on SIGSTOP any more, so we can't verify
2963 * signal delivery came from parent now (getpid() == info.si_pid).
2964 * https://lkml.kernel.org/r/CAGXu5jJaZAOzP1qFz66tYrtbuywqb+UN2SOA1VLHpCCOiYvYeg@mail.gmail.com
2965 * At least verify the SIGSTOP via PTRACE_GETSIGINFO.
2966 */
2967 EXPECT_EQ(SIGSTOP, info.si_signo);
2968
2969 /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
2970 ASSERT_EQ(0, kill(child_pid, SIGCONT));
2971 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2972 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2973 ASSERT_EQ(true, WIFSTOPPED(status));
2974 ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2975 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2976
2977 /* Wait for restart_syscall() to start. */
2978 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2979 ASSERT_EQ(true, WIFSTOPPED(status));
2980 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2981 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2982 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2983
2984 ASSERT_EQ(0x200, msg);
2985 ret = get_syscall(_metadata, child_pid);
2986 #if defined(__arm__)
2987 /*
2988 * FIXME:
2989 * - native ARM registers do NOT expose true syscall.
2990 * - compat ARM registers on ARM64 DO expose true syscall.
2991 */
2992 ASSERT_EQ(0, uname(&utsbuf));
2993 if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2994 EXPECT_EQ(__NR_nanosleep, ret);
2995 } else
2996 #endif
2997 {
2998 EXPECT_EQ(__NR_restart_syscall, ret);
2999 }
3000
3001 /* Write again to end test. */
3002 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
3003 ASSERT_EQ(1, write(pipefd[1], "!", 1));
3004 EXPECT_EQ(0, close(pipefd[1]));
3005
3006 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3007 if (WIFSIGNALED(status) || WEXITSTATUS(status))
3008 _metadata->passed = 0;
3009 }
3010
3011 TEST_SIGNAL(filter_flag_log, SIGSYS)
3012 {
3013 struct sock_filter allow_filter[] = {
3014 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3015 };
3016 struct sock_filter kill_filter[] = {
3017 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
3018 offsetof(struct seccomp_data, nr)),
3019 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
3020 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
3021 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3022 };
3023 struct sock_fprog allow_prog = {
3024 .len = (unsigned short)ARRAY_SIZE(allow_filter),
3025 .filter = allow_filter,
3026 };
3027 struct sock_fprog kill_prog = {
3028 .len = (unsigned short)ARRAY_SIZE(kill_filter),
3029 .filter = kill_filter,
3030 };
3031 long ret;
3032 pid_t parent = getppid();
3033
3034 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3035 ASSERT_EQ(0, ret);
3036
3037 /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
3038 ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
3039 &allow_prog);
3040 ASSERT_NE(ENOSYS, errno) {
3041 TH_LOG("Kernel does not support seccomp syscall!");
3042 }
3043 EXPECT_NE(0, ret) {
3044 TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
3045 }
3046 EXPECT_EQ(EINVAL, errno) {
3047 TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
3048 }
3049
3050 /* Verify that a simple, permissive filter can be added with no flags */
3051 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
3052 EXPECT_EQ(0, ret);
3053
3054 /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
3055 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
3056 &allow_prog);
3057 ASSERT_NE(EINVAL, errno) {
3058 TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
3059 }
3060 EXPECT_EQ(0, ret);
3061
3062 /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
3063 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
3064 &kill_prog);
3065 EXPECT_EQ(0, ret);
3066
3067 EXPECT_EQ(parent, syscall(__NR_getppid));
3068 /* getpid() should never return. */
3069 EXPECT_EQ(0, syscall(__NR_getpid));
3070 }
3071
3072 TEST(get_action_avail)
3073 {
3074 __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
3075 SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
3076 SECCOMP_RET_LOG, SECCOMP_RET_ALLOW };
3077 __u32 unknown_action = 0x10000000U;
3078 int i;
3079 long ret;
3080
3081 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
3082 ASSERT_NE(ENOSYS, errno) {
3083 TH_LOG("Kernel does not support seccomp syscall!");
3084 }
3085 ASSERT_NE(EINVAL, errno) {
3086 TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
3087 }
3088 EXPECT_EQ(ret, 0);
3089
3090 for (i = 0; i < ARRAY_SIZE(actions); i++) {
3091 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
3092 EXPECT_EQ(ret, 0) {
3093 TH_LOG("Expected action (0x%X) not available!",
3094 actions[i]);
3095 }
3096 }
3097
3098 /* Check that an unknown action is handled properly (EOPNOTSUPP) */
3099 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
3100 EXPECT_EQ(ret, -1);
3101 EXPECT_EQ(errno, EOPNOTSUPP);
3102 }
3103
3104 TEST(get_metadata)
3105 {
3106 pid_t pid;
3107 int pipefd[2];
3108 char buf;
3109 struct seccomp_metadata md;
3110 long ret;
3111
3112 /* Only real root can get metadata. */
3113 if (geteuid()) {
3114 SKIP(return, "get_metadata requires real root");
3115 return;
3116 }
3117
3118 ASSERT_EQ(0, pipe(pipefd));
3119
3120 pid = fork();
3121 ASSERT_GE(pid, 0);
3122 if (pid == 0) {
3123 struct sock_filter filter[] = {
3124 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3125 };
3126 struct sock_fprog prog = {
3127 .len = (unsigned short)ARRAY_SIZE(filter),
3128 .filter = filter,
3129 };
3130
3131 /* one with log, one without */
3132 EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
3133 SECCOMP_FILTER_FLAG_LOG, &prog));
3134 EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));
3135
3136 EXPECT_EQ(0, close(pipefd[0]));
3137 ASSERT_EQ(1, write(pipefd[1], "1", 1));
3138 ASSERT_EQ(0, close(pipefd[1]));
3139
3140 while (1)
3141 sleep(100);
3142 }
3143
3144 ASSERT_EQ(0, close(pipefd[1]));
3145 ASSERT_EQ(1, read(pipefd[0], &buf, 1));
3146
3147 ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
3148 ASSERT_EQ(pid, waitpid(pid, NULL, 0));
3149
3150 /* Past here must not use ASSERT or child process is never killed. */
3151
3152 md.filter_off = 0;
3153 errno = 0;
3154 ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
3155 EXPECT_EQ(sizeof(md), ret) {
3156 if (errno == EINVAL)
3157 SKIP(goto skip, "Kernel does not support PTRACE_SECCOMP_GET_METADATA (missing CONFIG_CHECKPOINT_RESTORE?)");
3158 }
3159
3160 EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
3161 EXPECT_EQ(md.filter_off, 0);
3162
3163 md.filter_off = 1;
3164 ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
3165 EXPECT_EQ(sizeof(md), ret);
3166 EXPECT_EQ(md.flags, 0);
3167 EXPECT_EQ(md.filter_off, 1);
3168
3169 skip:
3170 ASSERT_EQ(0, kill(pid, SIGKILL));
3171 }
3172
3173 static int user_notif_syscall(int nr, unsigned int flags)
3174 {
3175 struct sock_filter filter[] = {
3176 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
3177 offsetof(struct seccomp_data, nr)),
3178 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, nr, 0, 1),
3179 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_USER_NOTIF),
3180 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3181 };
3182
3183 struct sock_fprog prog = {
3184 .len = (unsigned short)ARRAY_SIZE(filter),
3185 .filter = filter,
3186 };
3187
3188 return seccomp(SECCOMP_SET_MODE_FILTER, flags, &prog);
3189 }
3190
3191 #define USER_NOTIF_MAGIC INT_MAX
3192 TEST(user_notification_basic)
3193 {
3194 pid_t pid;
3195 long ret;
3196 int status, listener;
3197 struct seccomp_notif req = {};
3198 struct seccomp_notif_resp resp = {};
3199 struct pollfd pollfd;
3200
3201 struct sock_filter filter[] = {
3202 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3203 };
3204 struct sock_fprog prog = {
3205 .len = (unsigned short)ARRAY_SIZE(filter),
3206 .filter = filter,
3207 };
3208
3209 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3210 ASSERT_EQ(0, ret) {
3211 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3212 }
3213
3214 pid = fork();
3215 ASSERT_GE(pid, 0);
3216
3217 /* Check that we get -ENOSYS with no listener attached */
3218 if (pid == 0) {
3219 if (user_notif_syscall(__NR_getppid, 0) < 0)
3220 exit(1);
3221 ret = syscall(__NR_getppid);
3222 exit(ret >= 0 || errno != ENOSYS);
3223 }
3224
3225 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3226 EXPECT_EQ(true, WIFEXITED(status));
3227 EXPECT_EQ(0, WEXITSTATUS(status));
3228
3229 /* Add some no-op filters for grins. */
3230 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3231 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3232 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3233 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3234
3235 /* Check that the basic notification machinery works */
3236 listener = user_notif_syscall(__NR_getppid,
3237 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3238 ASSERT_GE(listener, 0);
3239
3240 /* Installing a second listener in the chain should EBUSY */
3241 EXPECT_EQ(user_notif_syscall(__NR_getppid,
3242 SECCOMP_FILTER_FLAG_NEW_LISTENER),
3243 -1);
3244 EXPECT_EQ(errno, EBUSY);
3245
3246 pid = fork();
3247 ASSERT_GE(pid, 0);
3248
3249 if (pid == 0) {
3250 ret = syscall(__NR_getppid);
3251 exit(ret != USER_NOTIF_MAGIC);
3252 }
3253
3254 pollfd.fd = listener;
3255 pollfd.events = POLLIN | POLLOUT;
3256
3257 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3258 EXPECT_EQ(pollfd.revents, POLLIN);
3259
3260 /* Test that we can't pass garbage to the kernel. */
3261 memset(&req, 0, sizeof(req));
3262 req.pid = -1;
3263 errno = 0;
3264 ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req);
3265 EXPECT_EQ(-1, ret);
3266 EXPECT_EQ(EINVAL, errno);
3267
3268 if (ret) {
3269 req.pid = 0;
3270 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3271 }
3272
3273 pollfd.fd = listener;
3274 pollfd.events = POLLIN | POLLOUT;
3275
3276 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3277 EXPECT_EQ(pollfd.revents, POLLOUT);
3278
3279 EXPECT_EQ(req.data.nr, __NR_getppid);
3280
3281 resp.id = req.id;
3282 resp.error = 0;
3283 resp.val = USER_NOTIF_MAGIC;
3284
3285 /* check that we make sure flags == 0 */
3286 resp.flags = 1;
3287 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3288 EXPECT_EQ(errno, EINVAL);
3289
3290 resp.flags = 0;
3291 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3292
3293 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3294 EXPECT_EQ(true, WIFEXITED(status));
3295 EXPECT_EQ(0, WEXITSTATUS(status));
3296 }
3297
3298 TEST(user_notification_with_tsync)
3299 {
3300 int ret;
3301 unsigned int flags;
3302
3303 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3304 ASSERT_EQ(0, ret) {
3305 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3306 }
3307
3308 /* these were exclusive */
3309 flags = SECCOMP_FILTER_FLAG_NEW_LISTENER |
3310 SECCOMP_FILTER_FLAG_TSYNC;
3311 ASSERT_EQ(-1, user_notif_syscall(__NR_getppid, flags));
3312 ASSERT_EQ(EINVAL, errno);
3313
3314 /* but now they're not */
3315 flags |= SECCOMP_FILTER_FLAG_TSYNC_ESRCH;
3316 ret = user_notif_syscall(__NR_getppid, flags);
3317 close(ret);
3318 ASSERT_LE(0, ret);
3319 }
3320
3321 TEST(user_notification_kill_in_middle)
3322 {
3323 pid_t pid;
3324 long ret;
3325 int listener;
3326 struct seccomp_notif req = {};
3327 struct seccomp_notif_resp resp = {};
3328
3329 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3330 ASSERT_EQ(0, ret) {
3331 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3332 }
3333
3334 listener = user_notif_syscall(__NR_getppid,
3335 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3336 ASSERT_GE(listener, 0);
3337
3338 /*
3339 * Check that nothing bad happens when we kill the task in the middle
3340 * of a syscall.
3341 */
3342 pid = fork();
3343 ASSERT_GE(pid, 0);
3344
3345 if (pid == 0) {
3346 ret = syscall(__NR_getppid);
3347 exit(ret != USER_NOTIF_MAGIC);
3348 }
3349
3350 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3351 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), 0);
3352
3353 EXPECT_EQ(kill(pid, SIGKILL), 0);
3354 EXPECT_EQ(waitpid(pid, NULL, 0), pid);
3355
3356 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), -1);
3357
3358 resp.id = req.id;
3359 ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp);
3360 EXPECT_EQ(ret, -1);
3361 EXPECT_EQ(errno, ENOENT);
3362 }
3363
3364 static int handled = -1;
3365
3366 static void signal_handler(int signal)
3367 {
3368 if (write(handled, "c", 1) != 1)
3369 perror("write from signal");
3370 }
3371
3372 TEST(user_notification_signal)
3373 {
3374 pid_t pid;
3375 long ret;
3376 int status, listener, sk_pair[2];
3377 struct seccomp_notif req = {};
3378 struct seccomp_notif_resp resp = {};
3379 char c;
3380
3381 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3382 ASSERT_EQ(0, ret) {
3383 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3384 }
3385
3386 ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);
3387
3388 listener = user_notif_syscall(__NR_gettid,
3389 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3390 ASSERT_GE(listener, 0);
3391
3392 pid = fork();
3393 ASSERT_GE(pid, 0);
3394
3395 if (pid == 0) {
3396 close(sk_pair[0]);
3397 handled = sk_pair[1];
3398 if (signal(SIGUSR1, signal_handler) == SIG_ERR) {
3399 perror("signal");
3400 exit(1);
3401 }
3402 /*
3403 * ERESTARTSYS behavior is a bit hard to test, because we need
3404 * to rely on a signal that has not yet been handled. Let's at
3405 * least check that the error code gets propagated through, and
3406 * hope that it doesn't break when there is actually a signal :)
3407 */
3408 ret = syscall(__NR_gettid);
3409 exit(!(ret == -1 && errno == 512));
3410 }
3411
3412 close(sk_pair[1]);
3413
3414 memset(&req, 0, sizeof(req));
3415 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3416
3417 EXPECT_EQ(kill(pid, SIGUSR1), 0);
3418
3419 /*
3420 * Make sure the signal really is delivered, which means we're not
3421 * stuck in the user notification code any more and the notification
3422 * should be dead.
3423 */
3424 EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
3425
3426 resp.id = req.id;
3427 resp.error = -EPERM;
3428 resp.val = 0;
3429
3430 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3431 EXPECT_EQ(errno, ENOENT);
3432
3433 memset(&req, 0, sizeof(req));
3434 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3435
3436 resp.id = req.id;
3437 resp.error = -512; /* -ERESTARTSYS */
3438 resp.val = 0;
3439
3440 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3441
3442 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3443 EXPECT_EQ(true, WIFEXITED(status));
3444 EXPECT_EQ(0, WEXITSTATUS(status));
3445 }
3446
3447 TEST(user_notification_closed_listener)
3448 {
3449 pid_t pid;
3450 long ret;
3451 int status, listener;
3452
3453 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3454 ASSERT_EQ(0, ret) {
3455 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3456 }
3457
3458 listener = user_notif_syscall(__NR_getppid,
3459 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3460 ASSERT_GE(listener, 0);
3461
3462 /*
3463 * Check that we get an ENOSYS when the listener is closed.
3464 */
3465 pid = fork();
3466 ASSERT_GE(pid, 0);
3467 if (pid == 0) {
3468 close(listener);
3469 ret = syscall(__NR_getppid);
3470 exit(ret != -1 && errno != ENOSYS);
3471 }
3472
3473 close(listener);
3474
3475 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3476 EXPECT_EQ(true, WIFEXITED(status));
3477 EXPECT_EQ(0, WEXITSTATUS(status));
3478 }
3479
3480 /*
3481 * Check that a pid in a child namespace still shows up as valid in ours.
3482 */
3483 TEST(user_notification_child_pid_ns)
3484 {
3485 pid_t pid;
3486 int status, listener;
3487 struct seccomp_notif req = {};
3488 struct seccomp_notif_resp resp = {};
3489
3490 ASSERT_EQ(unshare(CLONE_NEWUSER | CLONE_NEWPID), 0) {
3491 if (errno == EINVAL)
3492 SKIP(return, "kernel missing CLONE_NEWUSER support");
3493 };
3494
3495 listener = user_notif_syscall(__NR_getppid,
3496 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3497 ASSERT_GE(listener, 0);
3498
3499 pid = fork();
3500 ASSERT_GE(pid, 0);
3501
3502 if (pid == 0)
3503 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3504
3505 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3506 EXPECT_EQ(req.pid, pid);
3507
3508 resp.id = req.id;
3509 resp.error = 0;
3510 resp.val = USER_NOTIF_MAGIC;
3511
3512 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3513
3514 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3515 EXPECT_EQ(true, WIFEXITED(status));
3516 EXPECT_EQ(0, WEXITSTATUS(status));
3517 close(listener);
3518 }
3519
3520 /*
3521 * Check that a pid in a sibling (i.e. unrelated) namespace shows up as 0, i.e.
3522 * invalid.
3523 */
3524 TEST(user_notification_sibling_pid_ns)
3525 {
3526 pid_t pid, pid2;
3527 int status, listener;
3528 struct seccomp_notif req = {};
3529 struct seccomp_notif_resp resp = {};
3530
3531 ASSERT_EQ(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0), 0) {
3532 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3533 }
3534
3535 listener = user_notif_syscall(__NR_getppid,
3536 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3537 ASSERT_GE(listener, 0);
3538
3539 pid = fork();
3540 ASSERT_GE(pid, 0);
3541
3542 if (pid == 0) {
3543 ASSERT_EQ(unshare(CLONE_NEWPID), 0);
3544
3545 pid2 = fork();
3546 ASSERT_GE(pid2, 0);
3547
3548 if (pid2 == 0)
3549 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3550
3551 EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
3552 EXPECT_EQ(true, WIFEXITED(status));
3553 EXPECT_EQ(0, WEXITSTATUS(status));
3554 exit(WEXITSTATUS(status));
3555 }
3556
3557 /* Create the sibling ns, and sibling in it. */
3558 ASSERT_EQ(unshare(CLONE_NEWPID), 0) {
3559 if (errno == EPERM)
3560 SKIP(return, "CLONE_NEWPID requires CAP_SYS_ADMIN");
3561 }
3562 ASSERT_EQ(errno, 0);
3563
3564 pid2 = fork();
3565 ASSERT_GE(pid2, 0);
3566
3567 if (pid2 == 0) {
3568 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3569 /*
3570 * The pid should be 0, i.e. the task is in some namespace that
3571 * we can't "see".
3572 */
3573 EXPECT_EQ(req.pid, 0);
3574
3575 resp.id = req.id;
3576 resp.error = 0;
3577 resp.val = USER_NOTIF_MAGIC;
3578
3579 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3580 exit(0);
3581 }
3582
3583 close(listener);
3584
3585 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3586 EXPECT_EQ(true, WIFEXITED(status));
3587 EXPECT_EQ(0, WEXITSTATUS(status));
3588
3589 EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
3590 EXPECT_EQ(true, WIFEXITED(status));
3591 EXPECT_EQ(0, WEXITSTATUS(status));
3592 }
3593
3594 TEST(user_notification_fault_recv)
3595 {
3596 pid_t pid;
3597 int status, listener;
3598 struct seccomp_notif req = {};
3599 struct seccomp_notif_resp resp = {};
3600
3601 ASSERT_EQ(unshare(CLONE_NEWUSER), 0);
3602
3603 listener = user_notif_syscall(__NR_getppid,
3604 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3605 ASSERT_GE(listener, 0);
3606
3607 pid = fork();
3608 ASSERT_GE(pid, 0);
3609
3610 if (pid == 0)
3611 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3612
3613 /* Do a bad recv() */
3614 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, NULL), -1);
3615 EXPECT_EQ(errno, EFAULT);
3616
3617 /* We should still be able to receive this notification, though. */
3618 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3619 EXPECT_EQ(req.pid, pid);
3620
3621 resp.id = req.id;
3622 resp.error = 0;
3623 resp.val = USER_NOTIF_MAGIC;
3624
3625 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3626
3627 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3628 EXPECT_EQ(true, WIFEXITED(status));
3629 EXPECT_EQ(0, WEXITSTATUS(status));
3630 }
3631
3632 TEST(seccomp_get_notif_sizes)
3633 {
3634 struct seccomp_notif_sizes sizes;
3635
3636 ASSERT_EQ(seccomp(SECCOMP_GET_NOTIF_SIZES, 0, &sizes), 0);
3637 EXPECT_EQ(sizes.seccomp_notif, sizeof(struct seccomp_notif));
3638 EXPECT_EQ(sizes.seccomp_notif_resp, sizeof(struct seccomp_notif_resp));
3639 }
3640
3641 TEST(user_notification_continue)
3642 {
3643 pid_t pid;
3644 long ret;
3645 int status, listener;
3646 struct seccomp_notif req = {};
3647 struct seccomp_notif_resp resp = {};
3648 struct pollfd pollfd;
3649
3650 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3651 ASSERT_EQ(0, ret) {
3652 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3653 }
3654
3655 listener = user_notif_syscall(__NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER);
3656 ASSERT_GE(listener, 0);
3657
3658 pid = fork();
3659 ASSERT_GE(pid, 0);
3660
3661 if (pid == 0) {
3662 int dup_fd, pipe_fds[2];
3663 pid_t self;
3664
3665 ASSERT_GE(pipe(pipe_fds), 0);
3666
3667 dup_fd = dup(pipe_fds[0]);
3668 ASSERT_GE(dup_fd, 0);
3669 EXPECT_NE(pipe_fds[0], dup_fd);
3670
3671 self = getpid();
3672 ASSERT_EQ(filecmp(self, self, pipe_fds[0], dup_fd), 0);
3673 exit(0);
3674 }
3675
3676 pollfd.fd = listener;
3677 pollfd.events = POLLIN | POLLOUT;
3678
3679 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3680 EXPECT_EQ(pollfd.revents, POLLIN);
3681
3682 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3683
3684 pollfd.fd = listener;
3685 pollfd.events = POLLIN | POLLOUT;
3686
3687 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3688 EXPECT_EQ(pollfd.revents, POLLOUT);
3689
3690 EXPECT_EQ(req.data.nr, __NR_dup);
3691
3692 resp.id = req.id;
3693 resp.flags = SECCOMP_USER_NOTIF_FLAG_CONTINUE;
3694
3695 /*
3696 * Verify that setting SECCOMP_USER_NOTIF_FLAG_CONTINUE enforces other
3697 * args be set to 0.
3698 */
3699 resp.error = 0;
3700 resp.val = USER_NOTIF_MAGIC;
3701 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3702 EXPECT_EQ(errno, EINVAL);
3703
3704 resp.error = USER_NOTIF_MAGIC;
3705 resp.val = 0;
3706 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3707 EXPECT_EQ(errno, EINVAL);
3708
3709 resp.error = 0;
3710 resp.val = 0;
3711 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0) {
3712 if (errno == EINVAL)
3713 SKIP(goto skip, "Kernel does not support SECCOMP_USER_NOTIF_FLAG_CONTINUE");
3714 }
3715
3716 skip:
3717 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3718 EXPECT_EQ(true, WIFEXITED(status));
3719 EXPECT_EQ(0, WEXITSTATUS(status)) {
3720 if (WEXITSTATUS(status) == 2) {
3721 SKIP(return, "Kernel does not support kcmp() syscall");
3722 return;
3723 }
3724 }
3725 }
3726
3727 TEST(user_notification_filter_empty)
3728 {
3729 pid_t pid;
3730 long ret;
3731 int status;
3732 struct pollfd pollfd;
3733 struct clone_args args = {
3734 .flags = CLONE_FILES,
3735 .exit_signal = SIGCHLD,
3736 };
3737
3738 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3739 ASSERT_EQ(0, ret) {
3740 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3741 }
3742
3743 pid = sys_clone3(&args, sizeof(args));
3744 ASSERT_GE(pid, 0);
3745
3746 if (pid == 0) {
3747 int listener;
3748
3749 listener = user_notif_syscall(__NR_mknodat, SECCOMP_FILTER_FLAG_NEW_LISTENER);
3750 if (listener < 0)
3751 _exit(EXIT_FAILURE);
3752
3753 if (dup2(listener, 200) != 200)
3754 _exit(EXIT_FAILURE);
3755
3756 close(listener);
3757
3758 _exit(EXIT_SUCCESS);
3759 }
3760
3761 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3762 EXPECT_EQ(true, WIFEXITED(status));
3763 EXPECT_EQ(0, WEXITSTATUS(status));
3764
3765 /*
3766 * The seccomp filter has become unused so we should be notified once
3767 * the kernel gets around to cleaning up task struct.
3768 */
3769 pollfd.fd = 200;
3770 pollfd.events = POLLHUP;
3771
3772 EXPECT_GT(poll(&pollfd, 1, 2000), 0);
3773 EXPECT_GT((pollfd.revents & POLLHUP) ?: 0, 0);
3774 }
3775
3776 static void *do_thread(void *data)
3777 {
3778 return NULL;
3779 }
3780
3781 TEST(user_notification_filter_empty_threaded)
3782 {
3783 pid_t pid;
3784 long ret;
3785 int status;
3786 struct pollfd pollfd;
3787 struct clone_args args = {
3788 .flags = CLONE_FILES,
3789 .exit_signal = SIGCHLD,
3790 };
3791
3792 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3793 ASSERT_EQ(0, ret) {
3794 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3795 }
3796
3797 pid = sys_clone3(&args, sizeof(args));
3798 ASSERT_GE(pid, 0);
3799
3800 if (pid == 0) {
3801 pid_t pid1, pid2;
3802 int listener, status;
3803 pthread_t thread;
3804
3805 listener = user_notif_syscall(__NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER);
3806 if (listener < 0)
3807 _exit(EXIT_FAILURE);
3808
3809 if (dup2(listener, 200) != 200)
3810 _exit(EXIT_FAILURE);
3811
3812 close(listener);
3813
3814 pid1 = fork();
3815 if (pid1 < 0)
3816 _exit(EXIT_FAILURE);
3817
3818 if (pid1 == 0)
3819 _exit(EXIT_SUCCESS);
3820
3821 pid2 = fork();
3822 if (pid2 < 0)
3823 _exit(EXIT_FAILURE);
3824
3825 if (pid2 == 0)
3826 _exit(EXIT_SUCCESS);
3827
3828 if (pthread_create(&thread, NULL, do_thread, NULL) ||
3829 pthread_join(thread, NULL))
3830 _exit(EXIT_FAILURE);
3831
3832 if (pthread_create(&thread, NULL, do_thread, NULL) ||
3833 pthread_join(thread, NULL))
3834 _exit(EXIT_FAILURE);
3835
3836 if (waitpid(pid1, &status, 0) != pid1 || !WIFEXITED(status) ||
3837 WEXITSTATUS(status))
3838 _exit(EXIT_FAILURE);
3839
3840 if (waitpid(pid2, &status, 0) != pid2 || !WIFEXITED(status) ||
3841 WEXITSTATUS(status))
3842 _exit(EXIT_FAILURE);
3843
3844 exit(EXIT_SUCCESS);
3845 }
3846
3847 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3848 EXPECT_EQ(true, WIFEXITED(status));
3849 EXPECT_EQ(0, WEXITSTATUS(status));
3850
3851 /*
3852 * The seccomp filter has become unused so we should be notified once
3853 * the kernel gets around to cleaning up task struct.
3854 */
3855 pollfd.fd = 200;
3856 pollfd.events = POLLHUP;
3857
3858 EXPECT_GT(poll(&pollfd, 1, 2000), 0);
3859 EXPECT_GT((pollfd.revents & POLLHUP) ?: 0, 0);
3860 }
3861
3862 TEST(user_notification_addfd)
3863 {
3864 pid_t pid;
3865 long ret;
3866 int status, listener, memfd, fd;
3867 struct seccomp_notif_addfd addfd = {};
3868 struct seccomp_notif_addfd_small small = {};
3869 struct seccomp_notif_addfd_big big = {};
3870 struct seccomp_notif req = {};
3871 struct seccomp_notif_resp resp = {};
3872 /* 100 ms */
3873 struct timespec delay = { .tv_nsec = 100000000 };
3874
3875 memfd = memfd_create("test", 0);
3876 ASSERT_GE(memfd, 0);
3877
3878 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3879 ASSERT_EQ(0, ret) {
3880 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3881 }
3882
3883 /* Check that the basic notification machinery works */
3884 listener = user_notif_syscall(__NR_getppid,
3885 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3886 ASSERT_GE(listener, 0);
3887
3888 pid = fork();
3889 ASSERT_GE(pid, 0);
3890
3891 if (pid == 0) {
3892 if (syscall(__NR_getppid) != USER_NOTIF_MAGIC)
3893 exit(1);
3894 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3895 }
3896
3897 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3898
3899 addfd.srcfd = memfd;
3900 addfd.newfd = 0;
3901 addfd.id = req.id;
3902 addfd.flags = 0x0;
3903
3904 /* Verify bad newfd_flags cannot be set */
3905 addfd.newfd_flags = ~O_CLOEXEC;
3906 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
3907 EXPECT_EQ(errno, EINVAL);
3908 addfd.newfd_flags = O_CLOEXEC;
3909
3910 /* Verify bad flags cannot be set */
3911 addfd.flags = 0xff;
3912 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
3913 EXPECT_EQ(errno, EINVAL);
3914 addfd.flags = 0;
3915
3916 /* Verify that remote_fd cannot be set without setting flags */
3917 addfd.newfd = 1;
3918 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
3919 EXPECT_EQ(errno, EINVAL);
3920 addfd.newfd = 0;
3921
3922 /* Verify small size cannot be set */
3923 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_SMALL, &small), -1);
3924 EXPECT_EQ(errno, EINVAL);
3925
3926 /* Verify we can't send bits filled in unknown buffer area */
3927 memset(&big, 0xAA, sizeof(big));
3928 big.addfd = addfd;
3929 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_BIG, &big), -1);
3930 EXPECT_EQ(errno, E2BIG);
3931
3932
3933 /* Verify we can set an arbitrary remote fd */
3934 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
3935 /*
3936 * The child has fds 0(stdin), 1(stdout), 2(stderr), 3(memfd),
3937 * 4(listener), so the newly allocated fd should be 5.
3938 */
3939 EXPECT_EQ(fd, 5);
3940 EXPECT_EQ(filecmp(getpid(), pid, memfd, fd), 0);
3941
3942 /* Verify we can set an arbitrary remote fd with large size */
3943 memset(&big, 0x0, sizeof(big));
3944 big.addfd = addfd;
3945 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_BIG, &big);
3946 EXPECT_EQ(fd, 6);
3947
3948 /* Verify we can set a specific remote fd */
3949 addfd.newfd = 42;
3950 addfd.flags = SECCOMP_ADDFD_FLAG_SETFD;
3951 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
3952 EXPECT_EQ(fd, 42);
3953 EXPECT_EQ(filecmp(getpid(), pid, memfd, fd), 0);
3954
3955 /* Resume syscall */
3956 resp.id = req.id;
3957 resp.error = 0;
3958 resp.val = USER_NOTIF_MAGIC;
3959 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3960
3961 /*
3962 * This sets the ID of the ADD FD to the last request plus 1. The
3963 * notification ID increments 1 per notification.
3964 */
3965 addfd.id = req.id + 1;
3966
3967 /* This spins until the underlying notification is generated */
3968 while (ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd) != -1 &&
3969 errno != -EINPROGRESS)
3970 nanosleep(&delay, NULL);
3971
3972 memset(&req, 0, sizeof(req));
3973 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3974 ASSERT_EQ(addfd.id, req.id);
3975
3976 resp.id = req.id;
3977 resp.error = 0;
3978 resp.val = USER_NOTIF_MAGIC;
3979 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3980
3981 /* Wait for child to finish. */
3982 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3983 EXPECT_EQ(true, WIFEXITED(status));
3984 EXPECT_EQ(0, WEXITSTATUS(status));
3985
3986 close(memfd);
3987 }
3988
3989 TEST(user_notification_addfd_rlimit)
3990 {
3991 pid_t pid;
3992 long ret;
3993 int status, listener, memfd;
3994 struct seccomp_notif_addfd addfd = {};
3995 struct seccomp_notif req = {};
3996 struct seccomp_notif_resp resp = {};
3997 const struct rlimit lim = {
3998 .rlim_cur = 0,
3999 .rlim_max = 0,
4000 };
4001
4002 memfd = memfd_create("test", 0);
4003 ASSERT_GE(memfd, 0);
4004
4005 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4006 ASSERT_EQ(0, ret) {
4007 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4008 }
4009
4010 /* Check that the basic notification machinery works */
4011 listener = user_notif_syscall(__NR_getppid,
4012 SECCOMP_FILTER_FLAG_NEW_LISTENER);
4013 ASSERT_GE(listener, 0);
4014
4015 pid = fork();
4016 ASSERT_GE(pid, 0);
4017
4018 if (pid == 0)
4019 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
4020
4021
4022 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4023
4024 ASSERT_EQ(prlimit(pid, RLIMIT_NOFILE, &lim, NULL), 0);
4025
4026 addfd.srcfd = memfd;
4027 addfd.newfd_flags = O_CLOEXEC;
4028 addfd.newfd = 0;
4029 addfd.id = req.id;
4030 addfd.flags = 0;
4031
4032 /* Should probably spot check /proc/sys/fs/file-nr */
4033 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4034 EXPECT_EQ(errno, EMFILE);
4035
4036 addfd.newfd = 100;
4037 addfd.flags = SECCOMP_ADDFD_FLAG_SETFD;
4038 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4039 EXPECT_EQ(errno, EBADF);
4040
4041 resp.id = req.id;
4042 resp.error = 0;
4043 resp.val = USER_NOTIF_MAGIC;
4044
4045 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4046
4047 /* Wait for child to finish. */
4048 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4049 EXPECT_EQ(true, WIFEXITED(status));
4050 EXPECT_EQ(0, WEXITSTATUS(status));
4051
4052 close(memfd);
4053 }
4054
4055 /*
4056 * TODO:
4057 * - expand NNP testing
4058 * - better arch-specific TRACE and TRAP handlers.
4059 * - endianness checking when appropriate
4060 * - 64-bit arg prodding
4061 * - arch value testing (x86 modes especially)
4062 * - verify that FILTER_FLAG_LOG filters generate log messages
4063 * - verify that RET_LOG generates log messages
4064 */
4065
4066 TEST_HARNESS_MAIN
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