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 #include <sys/capability.h>
50 #include <linux/perf_event.h>
51
52 #include <unistd.h>
53 #include <sys/syscall.h>
54 #include <poll.h>
55
56 #include "../kselftest_harness.h"
57 #include "../clone3/clone3_selftests.h"
58
59 /* Attempt to de-conflict with the selftests tree. */
60 #ifndef SKIP
61 #define SKIP(s, ...) XFAIL(s, ##__VA_ARGS__)
62 #endif
63
64 #ifndef MIN
65 #define MIN(X, Y) ((X) < (Y) ? (X) : (Y))
66 #endif
67
68 #ifndef PR_SET_PTRACER
69 # define PR_SET_PTRACER 0x59616d61
70 #endif
71
72 #ifndef noinline
73 #define noinline __attribute__((noinline))
74 #endif
75
76 #ifndef PR_SET_NO_NEW_PRIVS
77 #define PR_SET_NO_NEW_PRIVS 38
78 #define PR_GET_NO_NEW_PRIVS 39
79 #endif
80
81 #ifndef PR_SECCOMP_EXT
82 #define PR_SECCOMP_EXT 43
83 #endif
84
85 #ifndef SECCOMP_EXT_ACT
86 #define SECCOMP_EXT_ACT 1
87 #endif
88
89 #ifndef SECCOMP_EXT_ACT_TSYNC
90 #define SECCOMP_EXT_ACT_TSYNC 1
91 #endif
92
93 #ifndef SECCOMP_MODE_STRICT
94 #define SECCOMP_MODE_STRICT 1
95 #endif
96
97 #ifndef SECCOMP_MODE_FILTER
98 #define SECCOMP_MODE_FILTER 2
99 #endif
100
101 #ifndef SECCOMP_RET_ALLOW
102 struct seccomp_data {
103 int nr;
104 __u32 arch;
105 __u64 instruction_pointer;
106 __u64 args[6];
107 };
108 #endif
109
110 #ifndef SECCOMP_RET_KILL_PROCESS
111 #define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process */
112 #define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread */
113 #endif
114 #ifndef SECCOMP_RET_KILL
115 #define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD
116 #define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
117 #define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
118 #define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
119 #define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
120 #endif
121 #ifndef SECCOMP_RET_LOG
122 #define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */
123 #endif
124
125 #ifndef __NR_seccomp
126 # if defined(__i386__)
127 # define __NR_seccomp 354
128 # elif defined(__x86_64__)
129 # define __NR_seccomp 317
130 # elif defined(__arm__)
131 # define __NR_seccomp 383
132 # elif defined(__aarch64__)
133 # define __NR_seccomp 277
134 # elif defined(__riscv)
135 # define __NR_seccomp 277
136 # elif defined(__csky__)
137 # define __NR_seccomp 277
138 # elif defined(__loongarch__)
139 # define __NR_seccomp 277
140 # elif defined(__hppa__)
141 # define __NR_seccomp 338
142 # elif defined(__powerpc__)
143 # define __NR_seccomp 358
144 # elif defined(__s390__)
145 # define __NR_seccomp 348
146 # elif defined(__xtensa__)
147 # define __NR_seccomp 337
148 # elif defined(__sh__)
149 # define __NR_seccomp 372
150 # elif defined(__mc68000__)
151 # define __NR_seccomp 380
152 # else
153 # warning "seccomp syscall number unknown for this architecture"
154 # define __NR_seccomp 0xffff
155 # endif
156 #endif
157
158 #ifndef SECCOMP_SET_MODE_STRICT
159 #define SECCOMP_SET_MODE_STRICT 0
160 #endif
161
162 #ifndef SECCOMP_SET_MODE_FILTER
163 #define SECCOMP_SET_MODE_FILTER 1
164 #endif
165
166 #ifndef SECCOMP_GET_ACTION_AVAIL
167 #define SECCOMP_GET_ACTION_AVAIL 2
168 #endif
169
170 #ifndef SECCOMP_GET_NOTIF_SIZES
171 #define SECCOMP_GET_NOTIF_SIZES 3
172 #endif
173
174 #ifndef SECCOMP_FILTER_FLAG_TSYNC
175 #define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
176 #endif
177
178 #ifndef SECCOMP_FILTER_FLAG_LOG
179 #define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
180 #endif
181
182 #ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
183 #define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
184 #endif
185
186 #ifndef PTRACE_SECCOMP_GET_METADATA
187 #define PTRACE_SECCOMP_GET_METADATA 0x420d
188
189 struct seccomp_metadata {
190 __u64 filter_off; /* Input: which filter */
191 __u64 flags; /* Output: filter's flags */
192 };
193 #endif
194
195 #ifndef SECCOMP_FILTER_FLAG_NEW_LISTENER
196 #define SECCOMP_FILTER_FLAG_NEW_LISTENER (1UL << 3)
197 #endif
198
199 #ifndef SECCOMP_RET_USER_NOTIF
200 #define SECCOMP_RET_USER_NOTIF 0x7fc00000U
201
202 #define SECCOMP_IOC_MAGIC '!'
203 #define SECCOMP_IO(nr) _IO(SECCOMP_IOC_MAGIC, nr)
204 #define SECCOMP_IOR(nr, type) _IOR(SECCOMP_IOC_MAGIC, nr, type)
205 #define SECCOMP_IOW(nr, type) _IOW(SECCOMP_IOC_MAGIC, nr, type)
206 #define SECCOMP_IOWR(nr, type) _IOWR(SECCOMP_IOC_MAGIC, nr, type)
207
208 /* Flags for seccomp notification fd ioctl. */
209 #define SECCOMP_IOCTL_NOTIF_RECV SECCOMP_IOWR(0, struct seccomp_notif)
210 #define SECCOMP_IOCTL_NOTIF_SEND SECCOMP_IOWR(1, \
211 struct seccomp_notif_resp)
212 #define SECCOMP_IOCTL_NOTIF_ID_VALID SECCOMP_IOW(2, __u64)
213
214 struct seccomp_notif {
215 __u64 id;
216 __u32 pid;
217 __u32 flags;
218 struct seccomp_data data;
219 };
220
221 struct seccomp_notif_resp {
222 __u64 id;
223 __s64 val;
224 __s32 error;
225 __u32 flags;
226 };
227
228 struct seccomp_notif_sizes {
229 __u16 seccomp_notif;
230 __u16 seccomp_notif_resp;
231 __u16 seccomp_data;
232 };
233 #endif
234
235 #ifndef SECCOMP_IOCTL_NOTIF_ADDFD
236 /* On success, the return value is the remote process's added fd number */
237 #define SECCOMP_IOCTL_NOTIF_ADDFD SECCOMP_IOW(3, \
238 struct seccomp_notif_addfd)
239
240 /* valid flags for seccomp_notif_addfd */
241 #define SECCOMP_ADDFD_FLAG_SETFD (1UL << 0) /* Specify remote fd */
242
243 struct seccomp_notif_addfd {
244 __u64 id;
245 __u32 flags;
246 __u32 srcfd;
247 __u32 newfd;
248 __u32 newfd_flags;
249 };
250 #endif
251
252 #ifndef SECCOMP_ADDFD_FLAG_SEND
253 #define SECCOMP_ADDFD_FLAG_SEND (1UL << 1) /* Addfd and return it, atomically */
254 #endif
255
256 struct seccomp_notif_addfd_small {
257 __u64 id;
258 char weird[4];
259 };
260 #define SECCOMP_IOCTL_NOTIF_ADDFD_SMALL \
261 SECCOMP_IOW(3, struct seccomp_notif_addfd_small)
262
263 struct seccomp_notif_addfd_big {
264 union {
265 struct seccomp_notif_addfd addfd;
266 char buf[sizeof(struct seccomp_notif_addfd) + 8];
267 };
268 };
269 #define SECCOMP_IOCTL_NOTIF_ADDFD_BIG \
270 SECCOMP_IOWR(3, struct seccomp_notif_addfd_big)
271
272 #ifndef PTRACE_EVENTMSG_SYSCALL_ENTRY
273 #define PTRACE_EVENTMSG_SYSCALL_ENTRY 1
274 #define PTRACE_EVENTMSG_SYSCALL_EXIT 2
275 #endif
276
277 #ifndef SECCOMP_USER_NOTIF_FLAG_CONTINUE
278 #define SECCOMP_USER_NOTIF_FLAG_CONTINUE 0x00000001
279 #endif
280
281 #ifndef SECCOMP_FILTER_FLAG_TSYNC_ESRCH
282 #define SECCOMP_FILTER_FLAG_TSYNC_ESRCH (1UL << 4)
283 #endif
284
285 #ifndef SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV
286 #define SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV (1UL << 5)
287 #endif
288
289 #ifndef seccomp
seccomp(unsigned int op,unsigned int flags,void * args)290 int seccomp(unsigned int op, unsigned int flags, void *args)
291 {
292 errno = 0;
293 return syscall(__NR_seccomp, op, flags, args);
294 }
295 #endif
296
297 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
298 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
299 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
300 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
301 #else
302 #error "wut? Unknown __BYTE_ORDER__?!"
303 #endif
304
305 #define SIBLING_EXIT_UNKILLED 0xbadbeef
306 #define SIBLING_EXIT_FAILURE 0xbadface
307 #define SIBLING_EXIT_NEWPRIVS 0xbadfeed
308
__filecmp(pid_t pid1,pid_t pid2,int fd1,int fd2)309 static int __filecmp(pid_t pid1, pid_t pid2, int fd1, int fd2)
310 {
311 #ifdef __NR_kcmp
312 errno = 0;
313 return syscall(__NR_kcmp, pid1, pid2, KCMP_FILE, fd1, fd2);
314 #else
315 errno = ENOSYS;
316 return -1;
317 #endif
318 }
319
320 /* Have TH_LOG report actual location filecmp() is used. */
321 #define filecmp(pid1, pid2, fd1, fd2) ({ \
322 int _ret; \
323 \
324 _ret = __filecmp(pid1, pid2, fd1, fd2); \
325 if (_ret != 0) { \
326 if (_ret < 0 && errno == ENOSYS) { \
327 TH_LOG("kcmp() syscall missing (test is less accurate)");\
328 _ret = 0; \
329 } \
330 } \
331 _ret; })
332
TEST(kcmp)333 TEST(kcmp)
334 {
335 int ret;
336
337 ret = __filecmp(getpid(), getpid(), 1, 1);
338 EXPECT_EQ(ret, 0);
339 if (ret != 0 && errno == ENOSYS)
340 SKIP(return, "Kernel does not support kcmp() (missing CONFIG_KCMP?)");
341 }
342
TEST(mode_strict_support)343 TEST(mode_strict_support)
344 {
345 long ret;
346
347 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
348 ASSERT_EQ(0, ret) {
349 TH_LOG("Kernel does not support CONFIG_SECCOMP");
350 }
351 syscall(__NR_exit, 0);
352 }
353
TEST_SIGNAL(mode_strict_cannot_call_prctl,SIGKILL)354 TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
355 {
356 long ret;
357
358 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
359 ASSERT_EQ(0, ret) {
360 TH_LOG("Kernel does not support CONFIG_SECCOMP");
361 }
362 syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
363 NULL, NULL, NULL);
364 EXPECT_FALSE(true) {
365 TH_LOG("Unreachable!");
366 }
367 }
368
369 /* Note! This doesn't test no new privs behavior */
TEST(no_new_privs_support)370 TEST(no_new_privs_support)
371 {
372 long ret;
373
374 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
375 EXPECT_EQ(0, ret) {
376 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
377 }
378 }
379
380 /* Tests kernel support by checking for a copy_from_user() fault on NULL. */
TEST(mode_filter_support)381 TEST(mode_filter_support)
382 {
383 long ret;
384
385 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
386 ASSERT_EQ(0, ret) {
387 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
388 }
389 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
390 EXPECT_EQ(-1, ret);
391 EXPECT_EQ(EFAULT, errno) {
392 TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
393 }
394 }
395
TEST(mode_filter_without_nnp)396 TEST(mode_filter_without_nnp)
397 {
398 struct sock_filter filter[] = {
399 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
400 };
401 struct sock_fprog prog = {
402 .len = (unsigned short)ARRAY_SIZE(filter),
403 .filter = filter,
404 };
405 long ret;
406 cap_t cap = cap_get_proc();
407 cap_flag_value_t is_cap_sys_admin = 0;
408
409 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
410 ASSERT_LE(0, ret) {
411 TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
412 }
413 errno = 0;
414 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
415 /* Succeeds with CAP_SYS_ADMIN, fails without */
416 cap_get_flag(cap, CAP_SYS_ADMIN, CAP_EFFECTIVE, &is_cap_sys_admin);
417 if (!is_cap_sys_admin) {
418 EXPECT_EQ(-1, ret);
419 EXPECT_EQ(EACCES, errno);
420 } else {
421 EXPECT_EQ(0, ret);
422 }
423 }
424
425 #define MAX_INSNS_PER_PATH 32768
426
TEST(filter_size_limits)427 TEST(filter_size_limits)
428 {
429 int i;
430 int count = BPF_MAXINSNS + 1;
431 struct sock_filter allow[] = {
432 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
433 };
434 struct sock_filter *filter;
435 struct sock_fprog prog = { };
436 long ret;
437
438 filter = calloc(count, sizeof(*filter));
439 ASSERT_NE(NULL, filter);
440
441 for (i = 0; i < count; i++)
442 filter[i] = allow[0];
443
444 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
445 ASSERT_EQ(0, ret);
446
447 prog.filter = filter;
448 prog.len = count;
449
450 /* Too many filter instructions in a single filter. */
451 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
452 ASSERT_NE(0, ret) {
453 TH_LOG("Installing %d insn filter was allowed", prog.len);
454 }
455
456 /* One less is okay, though. */
457 prog.len -= 1;
458 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
459 ASSERT_EQ(0, ret) {
460 TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
461 }
462 }
463
TEST(filter_chain_limits)464 TEST(filter_chain_limits)
465 {
466 int i;
467 int count = BPF_MAXINSNS;
468 struct sock_filter allow[] = {
469 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
470 };
471 struct sock_filter *filter;
472 struct sock_fprog prog = { };
473 long ret;
474
475 filter = calloc(count, sizeof(*filter));
476 ASSERT_NE(NULL, filter);
477
478 for (i = 0; i < count; i++)
479 filter[i] = allow[0];
480
481 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
482 ASSERT_EQ(0, ret);
483
484 prog.filter = filter;
485 prog.len = 1;
486
487 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
488 ASSERT_EQ(0, ret);
489
490 prog.len = count;
491
492 /* Too many total filter instructions. */
493 for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
494 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
495 if (ret != 0)
496 break;
497 }
498 ASSERT_NE(0, ret) {
499 TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
500 i, count, i * (count + 4));
501 }
502 }
503
TEST(mode_filter_cannot_move_to_strict)504 TEST(mode_filter_cannot_move_to_strict)
505 {
506 struct sock_filter filter[] = {
507 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
508 };
509 struct sock_fprog prog = {
510 .len = (unsigned short)ARRAY_SIZE(filter),
511 .filter = filter,
512 };
513 long ret;
514
515 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
516 ASSERT_EQ(0, ret);
517
518 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
519 ASSERT_EQ(0, ret);
520
521 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
522 EXPECT_EQ(-1, ret);
523 EXPECT_EQ(EINVAL, errno);
524 }
525
526
TEST(mode_filter_get_seccomp)527 TEST(mode_filter_get_seccomp)
528 {
529 struct sock_filter filter[] = {
530 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
531 };
532 struct sock_fprog prog = {
533 .len = (unsigned short)ARRAY_SIZE(filter),
534 .filter = filter,
535 };
536 long ret;
537
538 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
539 ASSERT_EQ(0, ret);
540
541 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
542 EXPECT_EQ(0, ret);
543
544 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
545 ASSERT_EQ(0, ret);
546
547 ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
548 EXPECT_EQ(2, ret);
549 }
550
551
TEST(ALLOW_all)552 TEST(ALLOW_all)
553 {
554 struct sock_filter filter[] = {
555 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
556 };
557 struct sock_fprog prog = {
558 .len = (unsigned short)ARRAY_SIZE(filter),
559 .filter = filter,
560 };
561 long ret;
562
563 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
564 ASSERT_EQ(0, ret);
565
566 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
567 ASSERT_EQ(0, ret);
568 }
569
TEST(empty_prog)570 TEST(empty_prog)
571 {
572 struct sock_filter filter[] = {
573 };
574 struct sock_fprog prog = {
575 .len = (unsigned short)ARRAY_SIZE(filter),
576 .filter = filter,
577 };
578 long ret;
579
580 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
581 ASSERT_EQ(0, ret);
582
583 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
584 EXPECT_EQ(-1, ret);
585 EXPECT_EQ(EINVAL, errno);
586 }
587
TEST(log_all)588 TEST(log_all)
589 {
590 struct sock_filter filter[] = {
591 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
592 };
593 struct sock_fprog prog = {
594 .len = (unsigned short)ARRAY_SIZE(filter),
595 .filter = filter,
596 };
597 long ret;
598 pid_t parent = getppid();
599
600 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
601 ASSERT_EQ(0, ret);
602
603 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
604 ASSERT_EQ(0, ret);
605
606 /* getppid() should succeed and be logged (no check for logging) */
607 EXPECT_EQ(parent, syscall(__NR_getppid));
608 }
609
TEST_SIGNAL(unknown_ret_is_kill_inside,SIGSYS)610 TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
611 {
612 struct sock_filter filter[] = {
613 BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
614 };
615 struct sock_fprog prog = {
616 .len = (unsigned short)ARRAY_SIZE(filter),
617 .filter = filter,
618 };
619 long ret;
620
621 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
622 ASSERT_EQ(0, ret);
623
624 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
625 ASSERT_EQ(0, ret);
626 EXPECT_EQ(0, syscall(__NR_getpid)) {
627 TH_LOG("getpid() shouldn't ever return");
628 }
629 }
630
631 /* return code >= 0x80000000 is unused. */
TEST_SIGNAL(unknown_ret_is_kill_above_allow,SIGSYS)632 TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
633 {
634 struct sock_filter filter[] = {
635 BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
636 };
637 struct sock_fprog prog = {
638 .len = (unsigned short)ARRAY_SIZE(filter),
639 .filter = filter,
640 };
641 long ret;
642
643 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
644 ASSERT_EQ(0, ret);
645
646 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
647 ASSERT_EQ(0, ret);
648 EXPECT_EQ(0, syscall(__NR_getpid)) {
649 TH_LOG("getpid() shouldn't ever return");
650 }
651 }
652
TEST_SIGNAL(KILL_all,SIGSYS)653 TEST_SIGNAL(KILL_all, SIGSYS)
654 {
655 struct sock_filter filter[] = {
656 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
657 };
658 struct sock_fprog prog = {
659 .len = (unsigned short)ARRAY_SIZE(filter),
660 .filter = filter,
661 };
662 long ret;
663
664 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
665 ASSERT_EQ(0, ret);
666
667 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
668 ASSERT_EQ(0, ret);
669 }
670
TEST_SIGNAL(KILL_one,SIGSYS)671 TEST_SIGNAL(KILL_one, SIGSYS)
672 {
673 struct sock_filter filter[] = {
674 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
675 offsetof(struct seccomp_data, nr)),
676 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
677 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
678 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
679 };
680 struct sock_fprog prog = {
681 .len = (unsigned short)ARRAY_SIZE(filter),
682 .filter = filter,
683 };
684 long ret;
685 pid_t parent = getppid();
686
687 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
688 ASSERT_EQ(0, ret);
689
690 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
691 ASSERT_EQ(0, ret);
692
693 EXPECT_EQ(parent, syscall(__NR_getppid));
694 /* getpid() should never return. */
695 EXPECT_EQ(0, syscall(__NR_getpid));
696 }
697
TEST_SIGNAL(KILL_one_arg_one,SIGSYS)698 TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
699 {
700 void *fatal_address;
701 struct sock_filter filter[] = {
702 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
703 offsetof(struct seccomp_data, nr)),
704 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0),
705 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
706 /* Only both with lower 32-bit for now. */
707 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
708 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
709 (unsigned long)&fatal_address, 0, 1),
710 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
711 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
712 };
713 struct sock_fprog prog = {
714 .len = (unsigned short)ARRAY_SIZE(filter),
715 .filter = filter,
716 };
717 long ret;
718 pid_t parent = getppid();
719 struct tms timebuf;
720 clock_t clock = times(&timebuf);
721
722 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
723 ASSERT_EQ(0, ret);
724
725 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
726 ASSERT_EQ(0, ret);
727
728 EXPECT_EQ(parent, syscall(__NR_getppid));
729 EXPECT_LE(clock, syscall(__NR_times, &timebuf));
730 /* times() should never return. */
731 EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
732 }
733
TEST_SIGNAL(KILL_one_arg_six,SIGSYS)734 TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
735 {
736 #ifndef __NR_mmap2
737 int sysno = __NR_mmap;
738 #else
739 int sysno = __NR_mmap2;
740 #endif
741 struct sock_filter filter[] = {
742 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
743 offsetof(struct seccomp_data, nr)),
744 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0),
745 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
746 /* Only both with lower 32-bit for now. */
747 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
748 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
749 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
750 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
751 };
752 struct sock_fprog prog = {
753 .len = (unsigned short)ARRAY_SIZE(filter),
754 .filter = filter,
755 };
756 long ret;
757 pid_t parent = getppid();
758 int fd;
759 void *map1, *map2;
760 int page_size = sysconf(_SC_PAGESIZE);
761
762 ASSERT_LT(0, page_size);
763
764 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
765 ASSERT_EQ(0, ret);
766
767 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
768 ASSERT_EQ(0, ret);
769
770 fd = open("/dev/zero", O_RDONLY);
771 ASSERT_NE(-1, fd);
772
773 EXPECT_EQ(parent, syscall(__NR_getppid));
774 map1 = (void *)syscall(sysno,
775 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
776 EXPECT_NE(MAP_FAILED, map1);
777 /* mmap2() should never return. */
778 map2 = (void *)syscall(sysno,
779 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
780 EXPECT_EQ(MAP_FAILED, map2);
781
782 /* The test failed, so clean up the resources. */
783 munmap(map1, page_size);
784 munmap(map2, page_size);
785 close(fd);
786 }
787
788 /* This is a thread task to die via seccomp filter violation. */
kill_thread(void * data)789 void *kill_thread(void *data)
790 {
791 bool die = (bool)data;
792
793 if (die) {
794 syscall(__NR_getpid);
795 return (void *)SIBLING_EXIT_FAILURE;
796 }
797
798 return (void *)SIBLING_EXIT_UNKILLED;
799 }
800
801 enum kill_t {
802 KILL_THREAD,
803 KILL_PROCESS,
804 RET_UNKNOWN
805 };
806
807 /* Prepare a thread that will kill itself or both of us. */
kill_thread_or_group(struct __test_metadata * _metadata,enum kill_t kill_how)808 void kill_thread_or_group(struct __test_metadata *_metadata,
809 enum kill_t kill_how)
810 {
811 pthread_t thread;
812 void *status;
813 /* Kill only when calling __NR_getpid. */
814 struct sock_filter filter_thread[] = {
815 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
816 offsetof(struct seccomp_data, nr)),
817 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
818 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
819 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
820 };
821 struct sock_fprog prog_thread = {
822 .len = (unsigned short)ARRAY_SIZE(filter_thread),
823 .filter = filter_thread,
824 };
825 int kill = kill_how == KILL_PROCESS ? SECCOMP_RET_KILL_PROCESS : 0xAAAAAAAA;
826 struct sock_filter filter_process[] = {
827 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
828 offsetof(struct seccomp_data, nr)),
829 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
830 BPF_STMT(BPF_RET|BPF_K, kill),
831 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
832 };
833 struct sock_fprog prog_process = {
834 .len = (unsigned short)ARRAY_SIZE(filter_process),
835 .filter = filter_process,
836 };
837
838 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
839 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
840 }
841
842 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
843 kill_how == KILL_THREAD ? &prog_thread
844 : &prog_process));
845
846 /*
847 * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
848 * flag cannot be downgraded by a new filter.
849 */
850 if (kill_how == KILL_PROCESS)
851 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
852
853 /* Start a thread that will exit immediately. */
854 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
855 ASSERT_EQ(0, pthread_join(thread, &status));
856 ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
857
858 /* Start a thread that will die immediately. */
859 ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
860 ASSERT_EQ(0, pthread_join(thread, &status));
861 ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
862
863 /*
864 * If we get here, only the spawned thread died. Let the parent know
865 * the whole process didn't die (i.e. this thread, the spawner,
866 * stayed running).
867 */
868 exit(42);
869 }
870
TEST(KILL_thread)871 TEST(KILL_thread)
872 {
873 int status;
874 pid_t child_pid;
875
876 child_pid = fork();
877 ASSERT_LE(0, child_pid);
878 if (child_pid == 0) {
879 kill_thread_or_group(_metadata, KILL_THREAD);
880 _exit(38);
881 }
882
883 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
884
885 /* If only the thread was killed, we'll see exit 42. */
886 ASSERT_TRUE(WIFEXITED(status));
887 ASSERT_EQ(42, WEXITSTATUS(status));
888 }
889
TEST(KILL_process)890 TEST(KILL_process)
891 {
892 int status;
893 pid_t child_pid;
894
895 child_pid = fork();
896 ASSERT_LE(0, child_pid);
897 if (child_pid == 0) {
898 kill_thread_or_group(_metadata, KILL_PROCESS);
899 _exit(38);
900 }
901
902 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
903
904 /* If the entire process was killed, we'll see SIGSYS. */
905 ASSERT_TRUE(WIFSIGNALED(status));
906 ASSERT_EQ(SIGSYS, WTERMSIG(status));
907 }
908
TEST(KILL_unknown)909 TEST(KILL_unknown)
910 {
911 int status;
912 pid_t child_pid;
913
914 child_pid = fork();
915 ASSERT_LE(0, child_pid);
916 if (child_pid == 0) {
917 kill_thread_or_group(_metadata, RET_UNKNOWN);
918 _exit(38);
919 }
920
921 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
922
923 /* If the entire process was killed, we'll see SIGSYS. */
924 EXPECT_TRUE(WIFSIGNALED(status)) {
925 TH_LOG("Unknown SECCOMP_RET is only killing the thread?");
926 }
927 ASSERT_EQ(SIGSYS, WTERMSIG(status));
928 }
929
930 /* TODO(wad) add 64-bit versus 32-bit arg tests. */
TEST(arg_out_of_range)931 TEST(arg_out_of_range)
932 {
933 struct sock_filter filter[] = {
934 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
935 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
936 };
937 struct sock_fprog prog = {
938 .len = (unsigned short)ARRAY_SIZE(filter),
939 .filter = filter,
940 };
941 long ret;
942
943 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
944 ASSERT_EQ(0, ret);
945
946 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
947 EXPECT_EQ(-1, ret);
948 EXPECT_EQ(EINVAL, errno);
949 }
950
951 #define ERRNO_FILTER(name, errno) \
952 struct sock_filter _read_filter_##name[] = { \
953 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, \
954 offsetof(struct seccomp_data, nr)), \
955 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1), \
956 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | errno), \
957 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW), \
958 }; \
959 struct sock_fprog prog_##name = { \
960 .len = (unsigned short)ARRAY_SIZE(_read_filter_##name), \
961 .filter = _read_filter_##name, \
962 }
963
964 /* Make sure basic errno values are correctly passed through a filter. */
TEST(ERRNO_valid)965 TEST(ERRNO_valid)
966 {
967 ERRNO_FILTER(valid, E2BIG);
968 long ret;
969 pid_t parent = getppid();
970
971 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
972 ASSERT_EQ(0, ret);
973
974 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_valid);
975 ASSERT_EQ(0, ret);
976
977 EXPECT_EQ(parent, syscall(__NR_getppid));
978 EXPECT_EQ(-1, read(-1, NULL, 0));
979 EXPECT_EQ(E2BIG, errno);
980 }
981
982 /* Make sure an errno of zero is correctly handled by the arch code. */
TEST(ERRNO_zero)983 TEST(ERRNO_zero)
984 {
985 ERRNO_FILTER(zero, 0);
986 long ret;
987 pid_t parent = getppid();
988
989 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
990 ASSERT_EQ(0, ret);
991
992 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_zero);
993 ASSERT_EQ(0, ret);
994
995 EXPECT_EQ(parent, syscall(__NR_getppid));
996 /* "errno" of 0 is ok. */
997 EXPECT_EQ(0, read(-1, NULL, 0));
998 }
999
1000 /*
1001 * The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
1002 * This tests that the errno value gets capped correctly, fixed by
1003 * 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
1004 */
TEST(ERRNO_capped)1005 TEST(ERRNO_capped)
1006 {
1007 ERRNO_FILTER(capped, 4096);
1008 long ret;
1009 pid_t parent = getppid();
1010
1011 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1012 ASSERT_EQ(0, ret);
1013
1014 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_capped);
1015 ASSERT_EQ(0, ret);
1016
1017 EXPECT_EQ(parent, syscall(__NR_getppid));
1018 EXPECT_EQ(-1, read(-1, NULL, 0));
1019 EXPECT_EQ(4095, errno);
1020 }
1021
1022 /*
1023 * Filters are processed in reverse order: last applied is executed first.
1024 * Since only the SECCOMP_RET_ACTION mask is tested for return values, the
1025 * SECCOMP_RET_DATA mask results will follow the most recently applied
1026 * matching filter return (and not the lowest or highest value).
1027 */
TEST(ERRNO_order)1028 TEST(ERRNO_order)
1029 {
1030 ERRNO_FILTER(first, 11);
1031 ERRNO_FILTER(second, 13);
1032 ERRNO_FILTER(third, 12);
1033 long ret;
1034 pid_t parent = getppid();
1035
1036 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1037 ASSERT_EQ(0, ret);
1038
1039 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_first);
1040 ASSERT_EQ(0, ret);
1041
1042 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_second);
1043 ASSERT_EQ(0, ret);
1044
1045 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_third);
1046 ASSERT_EQ(0, ret);
1047
1048 EXPECT_EQ(parent, syscall(__NR_getppid));
1049 EXPECT_EQ(-1, read(-1, NULL, 0));
1050 EXPECT_EQ(12, errno);
1051 }
1052
FIXTURE(TRAP)1053 FIXTURE(TRAP) {
1054 struct sock_fprog prog;
1055 };
1056
FIXTURE_SETUP(TRAP)1057 FIXTURE_SETUP(TRAP)
1058 {
1059 struct sock_filter filter[] = {
1060 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1061 offsetof(struct seccomp_data, nr)),
1062 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1063 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
1064 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1065 };
1066
1067 memset(&self->prog, 0, sizeof(self->prog));
1068 self->prog.filter = malloc(sizeof(filter));
1069 ASSERT_NE(NULL, self->prog.filter);
1070 memcpy(self->prog.filter, filter, sizeof(filter));
1071 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1072 }
1073
FIXTURE_TEARDOWN(TRAP)1074 FIXTURE_TEARDOWN(TRAP)
1075 {
1076 if (self->prog.filter)
1077 free(self->prog.filter);
1078 }
1079
TEST_F_SIGNAL(TRAP,dfl,SIGSYS)1080 TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
1081 {
1082 long ret;
1083
1084 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1085 ASSERT_EQ(0, ret);
1086
1087 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
1088 ASSERT_EQ(0, ret);
1089 syscall(__NR_getpid);
1090 }
1091
1092 /* Ensure that SIGSYS overrides SIG_IGN */
TEST_F_SIGNAL(TRAP,ign,SIGSYS)1093 TEST_F_SIGNAL(TRAP, ign, SIGSYS)
1094 {
1095 long ret;
1096
1097 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1098 ASSERT_EQ(0, ret);
1099
1100 signal(SIGSYS, SIG_IGN);
1101
1102 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
1103 ASSERT_EQ(0, ret);
1104 syscall(__NR_getpid);
1105 }
1106
1107 static siginfo_t TRAP_info;
1108 static volatile int TRAP_nr;
TRAP_action(int nr,siginfo_t * info,void * void_context)1109 static void TRAP_action(int nr, siginfo_t *info, void *void_context)
1110 {
1111 memcpy(&TRAP_info, info, sizeof(TRAP_info));
1112 TRAP_nr = nr;
1113 }
1114
TEST_F(TRAP,handler)1115 TEST_F(TRAP, handler)
1116 {
1117 int ret, test;
1118 struct sigaction act;
1119 sigset_t mask;
1120
1121 memset(&act, 0, sizeof(act));
1122 sigemptyset(&mask);
1123 sigaddset(&mask, SIGSYS);
1124
1125 act.sa_sigaction = &TRAP_action;
1126 act.sa_flags = SA_SIGINFO;
1127 ret = sigaction(SIGSYS, &act, NULL);
1128 ASSERT_EQ(0, ret) {
1129 TH_LOG("sigaction failed");
1130 }
1131 ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
1132 ASSERT_EQ(0, ret) {
1133 TH_LOG("sigprocmask failed");
1134 }
1135
1136 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1137 ASSERT_EQ(0, ret);
1138 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
1139 ASSERT_EQ(0, ret);
1140 TRAP_nr = 0;
1141 memset(&TRAP_info, 0, sizeof(TRAP_info));
1142 /* Expect the registers to be rolled back. (nr = error) may vary
1143 * based on arch. */
1144 ret = syscall(__NR_getpid);
1145 /* Silence gcc warning about volatile. */
1146 test = TRAP_nr;
1147 EXPECT_EQ(SIGSYS, test);
1148 struct local_sigsys {
1149 void *_call_addr; /* calling user insn */
1150 int _syscall; /* triggering system call number */
1151 unsigned int _arch; /* AUDIT_ARCH_* of syscall */
1152 } *sigsys = (struct local_sigsys *)
1153 #ifdef si_syscall
1154 &(TRAP_info.si_call_addr);
1155 #else
1156 &TRAP_info.si_pid;
1157 #endif
1158 EXPECT_EQ(__NR_getpid, sigsys->_syscall);
1159 /* Make sure arch is non-zero. */
1160 EXPECT_NE(0, sigsys->_arch);
1161 EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
1162 }
1163
FIXTURE(precedence)1164 FIXTURE(precedence) {
1165 struct sock_fprog allow;
1166 struct sock_fprog log;
1167 struct sock_fprog trace;
1168 struct sock_fprog error;
1169 struct sock_fprog trap;
1170 struct sock_fprog kill;
1171 };
1172
FIXTURE_SETUP(precedence)1173 FIXTURE_SETUP(precedence)
1174 {
1175 struct sock_filter allow_insns[] = {
1176 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1177 };
1178 struct sock_filter log_insns[] = {
1179 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1180 offsetof(struct seccomp_data, nr)),
1181 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1182 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1183 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
1184 };
1185 struct sock_filter trace_insns[] = {
1186 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1187 offsetof(struct seccomp_data, nr)),
1188 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1189 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1190 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE),
1191 };
1192 struct sock_filter error_insns[] = {
1193 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1194 offsetof(struct seccomp_data, nr)),
1195 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1196 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1197 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO),
1198 };
1199 struct sock_filter trap_insns[] = {
1200 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1201 offsetof(struct seccomp_data, nr)),
1202 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1203 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1204 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
1205 };
1206 struct sock_filter kill_insns[] = {
1207 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1208 offsetof(struct seccomp_data, nr)),
1209 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1210 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1211 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1212 };
1213
1214 memset(self, 0, sizeof(*self));
1215 #define FILTER_ALLOC(_x) \
1216 self->_x.filter = malloc(sizeof(_x##_insns)); \
1217 ASSERT_NE(NULL, self->_x.filter); \
1218 memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
1219 self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
1220 FILTER_ALLOC(allow);
1221 FILTER_ALLOC(log);
1222 FILTER_ALLOC(trace);
1223 FILTER_ALLOC(error);
1224 FILTER_ALLOC(trap);
1225 FILTER_ALLOC(kill);
1226 }
1227
FIXTURE_TEARDOWN(precedence)1228 FIXTURE_TEARDOWN(precedence)
1229 {
1230 #define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
1231 FILTER_FREE(allow);
1232 FILTER_FREE(log);
1233 FILTER_FREE(trace);
1234 FILTER_FREE(error);
1235 FILTER_FREE(trap);
1236 FILTER_FREE(kill);
1237 }
1238
TEST_F(precedence,allow_ok)1239 TEST_F(precedence, allow_ok)
1240 {
1241 pid_t parent, res = 0;
1242 long ret;
1243
1244 parent = getppid();
1245 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1246 ASSERT_EQ(0, ret);
1247
1248 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1249 ASSERT_EQ(0, ret);
1250 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1251 ASSERT_EQ(0, ret);
1252 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1253 ASSERT_EQ(0, ret);
1254 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1255 ASSERT_EQ(0, ret);
1256 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1257 ASSERT_EQ(0, ret);
1258 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1259 ASSERT_EQ(0, ret);
1260 /* Should work just fine. */
1261 res = syscall(__NR_getppid);
1262 EXPECT_EQ(parent, res);
1263 }
1264
TEST_F_SIGNAL(precedence,kill_is_highest,SIGSYS)1265 TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
1266 {
1267 pid_t parent, res = 0;
1268 long ret;
1269
1270 parent = getppid();
1271 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1272 ASSERT_EQ(0, ret);
1273
1274 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1275 ASSERT_EQ(0, ret);
1276 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1277 ASSERT_EQ(0, ret);
1278 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1279 ASSERT_EQ(0, ret);
1280 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1281 ASSERT_EQ(0, ret);
1282 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1283 ASSERT_EQ(0, ret);
1284 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1285 ASSERT_EQ(0, ret);
1286 /* Should work just fine. */
1287 res = syscall(__NR_getppid);
1288 EXPECT_EQ(parent, res);
1289 /* getpid() should never return. */
1290 res = syscall(__NR_getpid);
1291 EXPECT_EQ(0, res);
1292 }
1293
TEST_F_SIGNAL(precedence,kill_is_highest_in_any_order,SIGSYS)1294 TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
1295 {
1296 pid_t parent;
1297 long ret;
1298
1299 parent = getppid();
1300 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1301 ASSERT_EQ(0, ret);
1302
1303 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1304 ASSERT_EQ(0, ret);
1305 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1306 ASSERT_EQ(0, ret);
1307 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1308 ASSERT_EQ(0, ret);
1309 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1310 ASSERT_EQ(0, ret);
1311 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1312 ASSERT_EQ(0, ret);
1313 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1314 ASSERT_EQ(0, ret);
1315 /* Should work just fine. */
1316 EXPECT_EQ(parent, syscall(__NR_getppid));
1317 /* getpid() should never return. */
1318 EXPECT_EQ(0, syscall(__NR_getpid));
1319 }
1320
TEST_F_SIGNAL(precedence,trap_is_second,SIGSYS)1321 TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
1322 {
1323 pid_t parent;
1324 long ret;
1325
1326 parent = getppid();
1327 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1328 ASSERT_EQ(0, ret);
1329
1330 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1331 ASSERT_EQ(0, ret);
1332 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1333 ASSERT_EQ(0, ret);
1334 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1335 ASSERT_EQ(0, ret);
1336 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1337 ASSERT_EQ(0, ret);
1338 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1339 ASSERT_EQ(0, ret);
1340 /* Should work just fine. */
1341 EXPECT_EQ(parent, syscall(__NR_getppid));
1342 /* getpid() should never return. */
1343 EXPECT_EQ(0, syscall(__NR_getpid));
1344 }
1345
TEST_F_SIGNAL(precedence,trap_is_second_in_any_order,SIGSYS)1346 TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
1347 {
1348 pid_t parent;
1349 long ret;
1350
1351 parent = getppid();
1352 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1353 ASSERT_EQ(0, ret);
1354
1355 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1356 ASSERT_EQ(0, ret);
1357 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1358 ASSERT_EQ(0, ret);
1359 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1360 ASSERT_EQ(0, ret);
1361 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1362 ASSERT_EQ(0, ret);
1363 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1364 ASSERT_EQ(0, ret);
1365 /* Should work just fine. */
1366 EXPECT_EQ(parent, syscall(__NR_getppid));
1367 /* getpid() should never return. */
1368 EXPECT_EQ(0, syscall(__NR_getpid));
1369 }
1370
TEST_F(precedence,errno_is_third)1371 TEST_F(precedence, errno_is_third)
1372 {
1373 pid_t parent;
1374 long ret;
1375
1376 parent = getppid();
1377 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1378 ASSERT_EQ(0, ret);
1379
1380 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1381 ASSERT_EQ(0, ret);
1382 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1383 ASSERT_EQ(0, ret);
1384 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1385 ASSERT_EQ(0, ret);
1386 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1387 ASSERT_EQ(0, ret);
1388 /* Should work just fine. */
1389 EXPECT_EQ(parent, syscall(__NR_getppid));
1390 EXPECT_EQ(0, syscall(__NR_getpid));
1391 }
1392
TEST_F(precedence,errno_is_third_in_any_order)1393 TEST_F(precedence, errno_is_third_in_any_order)
1394 {
1395 pid_t parent;
1396 long ret;
1397
1398 parent = getppid();
1399 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1400 ASSERT_EQ(0, ret);
1401
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->error);
1405 ASSERT_EQ(0, ret);
1406 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1407 ASSERT_EQ(0, ret);
1408 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1409 ASSERT_EQ(0, ret);
1410 /* Should work just fine. */
1411 EXPECT_EQ(parent, syscall(__NR_getppid));
1412 EXPECT_EQ(0, syscall(__NR_getpid));
1413 }
1414
TEST_F(precedence,trace_is_fourth)1415 TEST_F(precedence, trace_is_fourth)
1416 {
1417 pid_t parent;
1418 long ret;
1419
1420 parent = getppid();
1421 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1422 ASSERT_EQ(0, ret);
1423
1424 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1425 ASSERT_EQ(0, ret);
1426 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1427 ASSERT_EQ(0, ret);
1428 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1429 ASSERT_EQ(0, ret);
1430 /* Should work just fine. */
1431 EXPECT_EQ(parent, syscall(__NR_getppid));
1432 /* No ptracer */
1433 EXPECT_EQ(-1, syscall(__NR_getpid));
1434 }
1435
TEST_F(precedence,trace_is_fourth_in_any_order)1436 TEST_F(precedence, trace_is_fourth_in_any_order)
1437 {
1438 pid_t parent;
1439 long ret;
1440
1441 parent = getppid();
1442 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1443 ASSERT_EQ(0, ret);
1444
1445 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1446 ASSERT_EQ(0, ret);
1447 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1448 ASSERT_EQ(0, ret);
1449 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1450 ASSERT_EQ(0, ret);
1451 /* Should work just fine. */
1452 EXPECT_EQ(parent, syscall(__NR_getppid));
1453 /* No ptracer */
1454 EXPECT_EQ(-1, syscall(__NR_getpid));
1455 }
1456
TEST_F(precedence,log_is_fifth)1457 TEST_F(precedence, log_is_fifth)
1458 {
1459 pid_t mypid, parent;
1460 long ret;
1461
1462 mypid = getpid();
1463 parent = getppid();
1464 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1465 ASSERT_EQ(0, ret);
1466
1467 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1468 ASSERT_EQ(0, ret);
1469 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1470 ASSERT_EQ(0, ret);
1471 /* Should work just fine. */
1472 EXPECT_EQ(parent, syscall(__NR_getppid));
1473 /* Should also work just fine */
1474 EXPECT_EQ(mypid, syscall(__NR_getpid));
1475 }
1476
TEST_F(precedence,log_is_fifth_in_any_order)1477 TEST_F(precedence, log_is_fifth_in_any_order)
1478 {
1479 pid_t mypid, parent;
1480 long ret;
1481
1482 mypid = getpid();
1483 parent = getppid();
1484 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1485 ASSERT_EQ(0, ret);
1486
1487 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1488 ASSERT_EQ(0, ret);
1489 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1490 ASSERT_EQ(0, ret);
1491 /* Should work just fine. */
1492 EXPECT_EQ(parent, syscall(__NR_getppid));
1493 /* Should also work just fine */
1494 EXPECT_EQ(mypid, syscall(__NR_getpid));
1495 }
1496
1497 #ifndef PTRACE_O_TRACESECCOMP
1498 #define PTRACE_O_TRACESECCOMP 0x00000080
1499 #endif
1500
1501 /* Catch the Ubuntu 12.04 value error. */
1502 #if PTRACE_EVENT_SECCOMP != 7
1503 #undef PTRACE_EVENT_SECCOMP
1504 #endif
1505
1506 #ifndef PTRACE_EVENT_SECCOMP
1507 #define PTRACE_EVENT_SECCOMP 7
1508 #endif
1509
1510 #define PTRACE_EVENT_MASK(status) ((status) >> 16)
1511 bool tracer_running;
tracer_stop(int sig)1512 void tracer_stop(int sig)
1513 {
1514 tracer_running = false;
1515 }
1516
1517 typedef void tracer_func_t(struct __test_metadata *_metadata,
1518 pid_t tracee, int status, void *args);
1519
start_tracer(struct __test_metadata * _metadata,int fd,pid_t tracee,tracer_func_t tracer_func,void * args,bool ptrace_syscall)1520 void start_tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
1521 tracer_func_t tracer_func, void *args, bool ptrace_syscall)
1522 {
1523 int ret = -1;
1524 struct sigaction action = {
1525 .sa_handler = tracer_stop,
1526 };
1527
1528 /* Allow external shutdown. */
1529 tracer_running = true;
1530 ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));
1531
1532 errno = 0;
1533 while (ret == -1 && errno != EINVAL)
1534 ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
1535 ASSERT_EQ(0, ret) {
1536 kill(tracee, SIGKILL);
1537 }
1538 /* Wait for attach stop */
1539 wait(NULL);
1540
1541 ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, ptrace_syscall ?
1542 PTRACE_O_TRACESYSGOOD :
1543 PTRACE_O_TRACESECCOMP);
1544 ASSERT_EQ(0, ret) {
1545 TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
1546 kill(tracee, SIGKILL);
1547 }
1548 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1549 tracee, NULL, 0);
1550 ASSERT_EQ(0, ret);
1551
1552 /* Unblock the tracee */
1553 ASSERT_EQ(1, write(fd, "A", 1));
1554 ASSERT_EQ(0, close(fd));
1555
1556 /* Run until we're shut down. Must assert to stop execution. */
1557 while (tracer_running) {
1558 int status;
1559
1560 if (wait(&status) != tracee)
1561 continue;
1562
1563 if (WIFSIGNALED(status)) {
1564 /* Child caught a fatal signal. */
1565 return;
1566 }
1567 if (WIFEXITED(status)) {
1568 /* Child exited with code. */
1569 return;
1570 }
1571
1572 /* Check if we got an expected event. */
1573 ASSERT_EQ(WIFCONTINUED(status), false);
1574 ASSERT_EQ(WIFSTOPPED(status), true);
1575 ASSERT_EQ(WSTOPSIG(status) & SIGTRAP, SIGTRAP) {
1576 TH_LOG("Unexpected WSTOPSIG: %d", WSTOPSIG(status));
1577 }
1578
1579 tracer_func(_metadata, tracee, status, args);
1580
1581 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1582 tracee, NULL, 0);
1583 ASSERT_EQ(0, ret);
1584 }
1585 /* Directly report the status of our test harness results. */
1586 syscall(__NR_exit, _metadata->exit_code);
1587 }
1588
1589 /* Common tracer setup/teardown functions. */
cont_handler(int num)1590 void cont_handler(int num)
1591 { }
setup_trace_fixture(struct __test_metadata * _metadata,tracer_func_t func,void * args,bool ptrace_syscall)1592 pid_t setup_trace_fixture(struct __test_metadata *_metadata,
1593 tracer_func_t func, void *args, bool ptrace_syscall)
1594 {
1595 char sync;
1596 int pipefd[2];
1597 pid_t tracer_pid;
1598 pid_t tracee = getpid();
1599
1600 /* Setup a pipe for clean synchronization. */
1601 ASSERT_EQ(0, pipe(pipefd));
1602
1603 /* Fork a child which we'll promote to tracer */
1604 tracer_pid = fork();
1605 ASSERT_LE(0, tracer_pid);
1606 signal(SIGALRM, cont_handler);
1607 if (tracer_pid == 0) {
1608 close(pipefd[0]);
1609 start_tracer(_metadata, pipefd[1], tracee, func, args,
1610 ptrace_syscall);
1611 syscall(__NR_exit, 0);
1612 }
1613 close(pipefd[1]);
1614 prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
1615 read(pipefd[0], &sync, 1);
1616 close(pipefd[0]);
1617
1618 return tracer_pid;
1619 }
1620
teardown_trace_fixture(struct __test_metadata * _metadata,pid_t tracer)1621 void teardown_trace_fixture(struct __test_metadata *_metadata,
1622 pid_t tracer)
1623 {
1624 if (tracer) {
1625 int status;
1626 /*
1627 * Extract the exit code from the other process and
1628 * adopt it for ourselves in case its asserts failed.
1629 */
1630 ASSERT_EQ(0, kill(tracer, SIGUSR1));
1631 ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
1632 if (WEXITSTATUS(status))
1633 _metadata->exit_code = KSFT_FAIL;
1634 }
1635 }
1636
1637 /* "poke" tracer arguments and function. */
1638 struct tracer_args_poke_t {
1639 unsigned long poke_addr;
1640 };
1641
tracer_poke(struct __test_metadata * _metadata,pid_t tracee,int status,void * args)1642 void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
1643 void *args)
1644 {
1645 int ret;
1646 unsigned long msg;
1647 struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;
1648
1649 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1650 EXPECT_EQ(0, ret);
1651 /* If this fails, don't try to recover. */
1652 ASSERT_EQ(0x1001, msg) {
1653 kill(tracee, SIGKILL);
1654 }
1655 /*
1656 * Poke in the message.
1657 * Registers are not touched to try to keep this relatively arch
1658 * agnostic.
1659 */
1660 ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
1661 EXPECT_EQ(0, ret);
1662 }
1663
FIXTURE(TRACE_poke)1664 FIXTURE(TRACE_poke) {
1665 struct sock_fprog prog;
1666 pid_t tracer;
1667 long poked;
1668 struct tracer_args_poke_t tracer_args;
1669 };
1670
FIXTURE_SETUP(TRACE_poke)1671 FIXTURE_SETUP(TRACE_poke)
1672 {
1673 struct sock_filter filter[] = {
1674 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1675 offsetof(struct seccomp_data, nr)),
1676 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1677 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001),
1678 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1679 };
1680
1681 self->poked = 0;
1682 memset(&self->prog, 0, sizeof(self->prog));
1683 self->prog.filter = malloc(sizeof(filter));
1684 ASSERT_NE(NULL, self->prog.filter);
1685 memcpy(self->prog.filter, filter, sizeof(filter));
1686 self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1687
1688 /* Set up tracer args. */
1689 self->tracer_args.poke_addr = (unsigned long)&self->poked;
1690
1691 /* Launch tracer. */
1692 self->tracer = setup_trace_fixture(_metadata, tracer_poke,
1693 &self->tracer_args, false);
1694 }
1695
FIXTURE_TEARDOWN(TRACE_poke)1696 FIXTURE_TEARDOWN(TRACE_poke)
1697 {
1698 teardown_trace_fixture(_metadata, self->tracer);
1699 if (self->prog.filter)
1700 free(self->prog.filter);
1701 }
1702
TEST_F(TRACE_poke,read_has_side_effects)1703 TEST_F(TRACE_poke, read_has_side_effects)
1704 {
1705 ssize_t ret;
1706
1707 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1708 ASSERT_EQ(0, ret);
1709
1710 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1711 ASSERT_EQ(0, ret);
1712
1713 EXPECT_EQ(0, self->poked);
1714 ret = read(-1, NULL, 0);
1715 EXPECT_EQ(-1, ret);
1716 EXPECT_EQ(0x1001, self->poked);
1717 }
1718
TEST_F(TRACE_poke,getpid_runs_normally)1719 TEST_F(TRACE_poke, getpid_runs_normally)
1720 {
1721 long ret;
1722
1723 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1724 ASSERT_EQ(0, ret);
1725
1726 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1727 ASSERT_EQ(0, ret);
1728
1729 EXPECT_EQ(0, self->poked);
1730 EXPECT_NE(0, syscall(__NR_getpid));
1731 EXPECT_EQ(0, self->poked);
1732 }
1733
1734 #if defined(__x86_64__)
1735 # define ARCH_REGS struct user_regs_struct
1736 # define SYSCALL_NUM(_regs) (_regs).orig_rax
1737 # define SYSCALL_RET(_regs) (_regs).rax
1738 #elif defined(__i386__)
1739 # define ARCH_REGS struct user_regs_struct
1740 # define SYSCALL_NUM(_regs) (_regs).orig_eax
1741 # define SYSCALL_RET(_regs) (_regs).eax
1742 #elif defined(__arm__)
1743 # define ARCH_REGS struct pt_regs
1744 # define SYSCALL_NUM(_regs) (_regs).ARM_r7
1745 # ifndef PTRACE_SET_SYSCALL
1746 # define PTRACE_SET_SYSCALL 23
1747 # endif
1748 # define SYSCALL_NUM_SET(_regs, _nr) \
1749 EXPECT_EQ(0, ptrace(PTRACE_SET_SYSCALL, tracee, NULL, _nr))
1750 # define SYSCALL_RET(_regs) (_regs).ARM_r0
1751 #elif defined(__aarch64__)
1752 # define ARCH_REGS struct user_pt_regs
1753 # define SYSCALL_NUM(_regs) (_regs).regs[8]
1754 # ifndef NT_ARM_SYSTEM_CALL
1755 # define NT_ARM_SYSTEM_CALL 0x404
1756 # endif
1757 # define SYSCALL_NUM_SET(_regs, _nr) \
1758 do { \
1759 struct iovec __v; \
1760 typeof(_nr) __nr = (_nr); \
1761 __v.iov_base = &__nr; \
1762 __v.iov_len = sizeof(__nr); \
1763 EXPECT_EQ(0, ptrace(PTRACE_SETREGSET, tracee, \
1764 NT_ARM_SYSTEM_CALL, &__v)); \
1765 } while (0)
1766 # define SYSCALL_RET(_regs) (_regs).regs[0]
1767 #elif defined(__loongarch__)
1768 # define ARCH_REGS struct user_pt_regs
1769 # define SYSCALL_NUM(_regs) (_regs).regs[11]
1770 # define SYSCALL_RET(_regs) (_regs).regs[4]
1771 #elif defined(__riscv) && __riscv_xlen == 64
1772 # define ARCH_REGS struct user_regs_struct
1773 # define SYSCALL_NUM(_regs) (_regs).a7
1774 # define SYSCALL_RET(_regs) (_regs).a0
1775 #elif defined(__csky__)
1776 # define ARCH_REGS struct pt_regs
1777 # if defined(__CSKYABIV2__)
1778 # define SYSCALL_NUM(_regs) (_regs).regs[3]
1779 # else
1780 # define SYSCALL_NUM(_regs) (_regs).regs[9]
1781 # endif
1782 # define SYSCALL_RET(_regs) (_regs).a0
1783 #elif defined(__hppa__)
1784 # define ARCH_REGS struct user_regs_struct
1785 # define SYSCALL_NUM(_regs) (_regs).gr[20]
1786 # define SYSCALL_RET(_regs) (_regs).gr[28]
1787 #elif defined(__powerpc__)
1788 # define ARCH_REGS struct pt_regs
1789 # define SYSCALL_NUM(_regs) (_regs).gpr[0]
1790 # define SYSCALL_RET(_regs) (_regs).gpr[3]
1791 # define SYSCALL_RET_SET(_regs, _val) \
1792 do { \
1793 typeof(_val) _result = (_val); \
1794 if ((_regs.trap & 0xfff0) == 0x3000) { \
1795 /* \
1796 * scv 0 system call uses -ve result \
1797 * for error, so no need to adjust. \
1798 */ \
1799 SYSCALL_RET(_regs) = _result; \
1800 } else { \
1801 /* \
1802 * A syscall error is signaled by the \
1803 * CR0 SO bit and the code is stored as \
1804 * a positive value. \
1805 */ \
1806 if (_result < 0) { \
1807 SYSCALL_RET(_regs) = -_result; \
1808 (_regs).ccr |= 0x10000000; \
1809 } else { \
1810 SYSCALL_RET(_regs) = _result; \
1811 (_regs).ccr &= ~0x10000000; \
1812 } \
1813 } \
1814 } while (0)
1815 # define SYSCALL_RET_SET_ON_PTRACE_EXIT
1816 #elif defined(__s390__)
1817 # define ARCH_REGS s390_regs
1818 # define SYSCALL_NUM(_regs) (_regs).gprs[2]
1819 # define SYSCALL_RET_SET(_regs, _val) \
1820 TH_LOG("Can't modify syscall return on this architecture")
1821 #elif defined(__mips__)
1822 # include <asm/unistd_nr_n32.h>
1823 # include <asm/unistd_nr_n64.h>
1824 # include <asm/unistd_nr_o32.h>
1825 # define ARCH_REGS struct pt_regs
1826 # define SYSCALL_NUM(_regs) \
1827 ({ \
1828 typeof((_regs).regs[2]) _nr; \
1829 if ((_regs).regs[2] == __NR_O32_Linux) \
1830 _nr = (_regs).regs[4]; \
1831 else \
1832 _nr = (_regs).regs[2]; \
1833 _nr; \
1834 })
1835 # define SYSCALL_NUM_SET(_regs, _nr) \
1836 do { \
1837 if ((_regs).regs[2] == __NR_O32_Linux) \
1838 (_regs).regs[4] = _nr; \
1839 else \
1840 (_regs).regs[2] = _nr; \
1841 } while (0)
1842 # define SYSCALL_RET_SET(_regs, _val) \
1843 TH_LOG("Can't modify syscall return on this architecture")
1844 #elif defined(__xtensa__)
1845 # define ARCH_REGS struct user_pt_regs
1846 # define SYSCALL_NUM(_regs) (_regs).syscall
1847 /*
1848 * On xtensa syscall return value is in the register
1849 * a2 of the current window which is not fixed.
1850 */
1851 #define SYSCALL_RET(_regs) (_regs).a[(_regs).windowbase * 4 + 2]
1852 #elif defined(__sh__)
1853 # define ARCH_REGS struct pt_regs
1854 # define SYSCALL_NUM(_regs) (_regs).regs[3]
1855 # define SYSCALL_RET(_regs) (_regs).regs[0]
1856 #elif defined(__mc68000__)
1857 # define ARCH_REGS struct user_regs_struct
1858 # define SYSCALL_NUM(_regs) (_regs).orig_d0
1859 # define SYSCALL_RET(_regs) (_regs).d0
1860 #else
1861 # error "Do not know how to find your architecture's registers and syscalls"
1862 #endif
1863
1864 /*
1865 * Most architectures can change the syscall by just updating the
1866 * associated register. This is the default if not defined above.
1867 */
1868 #ifndef SYSCALL_NUM_SET
1869 # define SYSCALL_NUM_SET(_regs, _nr) \
1870 do { \
1871 SYSCALL_NUM(_regs) = (_nr); \
1872 } while (0)
1873 #endif
1874 /*
1875 * Most architectures can change the syscall return value by just
1876 * writing to the SYSCALL_RET register. This is the default if not
1877 * defined above. If an architecture cannot set the return value
1878 * (for example when the syscall and return value register is
1879 * shared), report it with TH_LOG() in an arch-specific definition
1880 * of SYSCALL_RET_SET() above, and leave SYSCALL_RET undefined.
1881 */
1882 #if !defined(SYSCALL_RET) && !defined(SYSCALL_RET_SET)
1883 # error "One of SYSCALL_RET or SYSCALL_RET_SET is needed for this arch"
1884 #endif
1885 #ifndef SYSCALL_RET_SET
1886 # define SYSCALL_RET_SET(_regs, _val) \
1887 do { \
1888 SYSCALL_RET(_regs) = (_val); \
1889 } while (0)
1890 #endif
1891
1892 /* When the syscall return can't be changed, stub out the tests for it. */
1893 #ifndef SYSCALL_RET
1894 # define EXPECT_SYSCALL_RETURN(val, action) EXPECT_EQ(-1, action)
1895 #else
1896 # define EXPECT_SYSCALL_RETURN(val, action) \
1897 do { \
1898 errno = 0; \
1899 if (val < 0) { \
1900 EXPECT_EQ(-1, action); \
1901 EXPECT_EQ(-(val), errno); \
1902 } else { \
1903 EXPECT_EQ(val, action); \
1904 } \
1905 } while (0)
1906 #endif
1907
1908 /*
1909 * Some architectures (e.g. powerpc) can only set syscall
1910 * return values on syscall exit during ptrace.
1911 */
1912 const bool ptrace_entry_set_syscall_nr = true;
1913 const bool ptrace_entry_set_syscall_ret =
1914 #ifndef SYSCALL_RET_SET_ON_PTRACE_EXIT
1915 true;
1916 #else
1917 false;
1918 #endif
1919
1920 /*
1921 * Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1922 * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1923 */
1924 #if defined(__x86_64__) || defined(__i386__) || defined(__mips__) || defined(__mc68000__)
1925 # define ARCH_GETREGS(_regs) ptrace(PTRACE_GETREGS, tracee, 0, &(_regs))
1926 # define ARCH_SETREGS(_regs) ptrace(PTRACE_SETREGS, tracee, 0, &(_regs))
1927 #else
1928 # define ARCH_GETREGS(_regs) ({ \
1929 struct iovec __v; \
1930 __v.iov_base = &(_regs); \
1931 __v.iov_len = sizeof(_regs); \
1932 ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &__v); \
1933 })
1934 # define ARCH_SETREGS(_regs) ({ \
1935 struct iovec __v; \
1936 __v.iov_base = &(_regs); \
1937 __v.iov_len = sizeof(_regs); \
1938 ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &__v); \
1939 })
1940 #endif
1941
1942 /* Architecture-specific syscall fetching routine. */
get_syscall(struct __test_metadata * _metadata,pid_t tracee)1943 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1944 {
1945 ARCH_REGS regs;
1946
1947 EXPECT_EQ(0, ARCH_GETREGS(regs)) {
1948 return -1;
1949 }
1950
1951 return SYSCALL_NUM(regs);
1952 }
1953
1954 /* Architecture-specific syscall changing routine. */
__change_syscall(struct __test_metadata * _metadata,pid_t tracee,long * syscall,long * ret)1955 void __change_syscall(struct __test_metadata *_metadata,
1956 pid_t tracee, long *syscall, long *ret)
1957 {
1958 ARCH_REGS orig, regs;
1959
1960 /* Do not get/set registers if we have nothing to do. */
1961 if (!syscall && !ret)
1962 return;
1963
1964 EXPECT_EQ(0, ARCH_GETREGS(regs)) {
1965 return;
1966 }
1967 orig = regs;
1968
1969 if (syscall)
1970 SYSCALL_NUM_SET(regs, *syscall);
1971
1972 if (ret)
1973 SYSCALL_RET_SET(regs, *ret);
1974
1975 /* Flush any register changes made. */
1976 if (memcmp(&orig, ®s, sizeof(orig)) != 0)
1977 EXPECT_EQ(0, ARCH_SETREGS(regs));
1978 }
1979
1980 /* Change only syscall number. */
change_syscall_nr(struct __test_metadata * _metadata,pid_t tracee,long syscall)1981 void change_syscall_nr(struct __test_metadata *_metadata,
1982 pid_t tracee, long syscall)
1983 {
1984 __change_syscall(_metadata, tracee, &syscall, NULL);
1985 }
1986
1987 /* Change syscall return value (and set syscall number to -1). */
change_syscall_ret(struct __test_metadata * _metadata,pid_t tracee,long ret)1988 void change_syscall_ret(struct __test_metadata *_metadata,
1989 pid_t tracee, long ret)
1990 {
1991 long syscall = -1;
1992
1993 __change_syscall(_metadata, tracee, &syscall, &ret);
1994 }
1995
tracer_seccomp(struct __test_metadata * _metadata,pid_t tracee,int status,void * args)1996 void tracer_seccomp(struct __test_metadata *_metadata, pid_t tracee,
1997 int status, void *args)
1998 {
1999 int ret;
2000 unsigned long msg;
2001
2002 EXPECT_EQ(PTRACE_EVENT_MASK(status), PTRACE_EVENT_SECCOMP) {
2003 TH_LOG("Unexpected ptrace event: %d", PTRACE_EVENT_MASK(status));
2004 return;
2005 }
2006
2007 /* Make sure we got the right message. */
2008 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
2009 EXPECT_EQ(0, ret);
2010
2011 /* Validate and take action on expected syscalls. */
2012 switch (msg) {
2013 case 0x1002:
2014 /* change getpid to getppid. */
2015 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
2016 change_syscall_nr(_metadata, tracee, __NR_getppid);
2017 break;
2018 case 0x1003:
2019 /* skip gettid with valid return code. */
2020 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
2021 change_syscall_ret(_metadata, tracee, 45000);
2022 break;
2023 case 0x1004:
2024 /* skip openat with error. */
2025 EXPECT_EQ(__NR_openat, get_syscall(_metadata, tracee));
2026 change_syscall_ret(_metadata, tracee, -ESRCH);
2027 break;
2028 case 0x1005:
2029 /* do nothing (allow getppid) */
2030 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
2031 break;
2032 default:
2033 EXPECT_EQ(0, msg) {
2034 TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
2035 kill(tracee, SIGKILL);
2036 }
2037 }
2038
2039 }
2040
FIXTURE(TRACE_syscall)2041 FIXTURE(TRACE_syscall) {
2042 struct sock_fprog prog;
2043 pid_t tracer, mytid, mypid, parent;
2044 long syscall_nr;
2045 };
2046
tracer_ptrace(struct __test_metadata * _metadata,pid_t tracee,int status,void * args)2047 void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
2048 int status, void *args)
2049 {
2050 int ret;
2051 unsigned long msg;
2052 static bool entry;
2053 long syscall_nr_val, syscall_ret_val;
2054 long *syscall_nr = NULL, *syscall_ret = NULL;
2055 FIXTURE_DATA(TRACE_syscall) *self = args;
2056
2057 EXPECT_EQ(WSTOPSIG(status) & 0x80, 0x80) {
2058 TH_LOG("Unexpected WSTOPSIG: %d", WSTOPSIG(status));
2059 return;
2060 }
2061
2062 /*
2063 * The traditional way to tell PTRACE_SYSCALL entry/exit
2064 * is by counting.
2065 */
2066 entry = !entry;
2067
2068 /* Make sure we got an appropriate message. */
2069 ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
2070 EXPECT_EQ(0, ret);
2071 EXPECT_EQ(entry ? PTRACE_EVENTMSG_SYSCALL_ENTRY
2072 : PTRACE_EVENTMSG_SYSCALL_EXIT, msg);
2073
2074 /*
2075 * Some architectures only support setting return values during
2076 * syscall exit under ptrace, and on exit the syscall number may
2077 * no longer be available. Therefore, save the initial sycall
2078 * number here, so it can be examined during both entry and exit
2079 * phases.
2080 */
2081 if (entry)
2082 self->syscall_nr = get_syscall(_metadata, tracee);
2083
2084 /*
2085 * Depending on the architecture's syscall setting abilities, we
2086 * pick which things to set during this phase (entry or exit).
2087 */
2088 if (entry == ptrace_entry_set_syscall_nr)
2089 syscall_nr = &syscall_nr_val;
2090 if (entry == ptrace_entry_set_syscall_ret)
2091 syscall_ret = &syscall_ret_val;
2092
2093 /* Now handle the actual rewriting cases. */
2094 switch (self->syscall_nr) {
2095 case __NR_getpid:
2096 syscall_nr_val = __NR_getppid;
2097 /* Never change syscall return for this case. */
2098 syscall_ret = NULL;
2099 break;
2100 case __NR_gettid:
2101 syscall_nr_val = -1;
2102 syscall_ret_val = 45000;
2103 break;
2104 case __NR_openat:
2105 syscall_nr_val = -1;
2106 syscall_ret_val = -ESRCH;
2107 break;
2108 default:
2109 /* Unhandled, do nothing. */
2110 return;
2111 }
2112
2113 __change_syscall(_metadata, tracee, syscall_nr, syscall_ret);
2114 }
2115
FIXTURE_VARIANT(TRACE_syscall)2116 FIXTURE_VARIANT(TRACE_syscall) {
2117 /*
2118 * All of the SECCOMP_RET_TRACE behaviors can be tested with either
2119 * SECCOMP_RET_TRACE+PTRACE_CONT or plain ptrace()+PTRACE_SYSCALL.
2120 * This indicates if we should use SECCOMP_RET_TRACE (false), or
2121 * ptrace (true).
2122 */
2123 bool use_ptrace;
2124 };
2125
FIXTURE_VARIANT_ADD(TRACE_syscall,ptrace)2126 FIXTURE_VARIANT_ADD(TRACE_syscall, ptrace) {
2127 .use_ptrace = true,
2128 };
2129
FIXTURE_VARIANT_ADD(TRACE_syscall,seccomp)2130 FIXTURE_VARIANT_ADD(TRACE_syscall, seccomp) {
2131 .use_ptrace = false,
2132 };
2133
FIXTURE_SETUP(TRACE_syscall)2134 FIXTURE_SETUP(TRACE_syscall)
2135 {
2136 struct sock_filter filter[] = {
2137 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2138 offsetof(struct seccomp_data, nr)),
2139 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
2140 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
2141 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
2142 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
2143 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_openat, 0, 1),
2144 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
2145 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2146 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1005),
2147 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2148 };
2149 struct sock_fprog prog = {
2150 .len = (unsigned short)ARRAY_SIZE(filter),
2151 .filter = filter,
2152 };
2153 long ret;
2154
2155 /* Prepare some testable syscall results. */
2156 self->mytid = syscall(__NR_gettid);
2157 ASSERT_GT(self->mytid, 0);
2158 ASSERT_NE(self->mytid, 1) {
2159 TH_LOG("Running this test as init is not supported. :)");
2160 }
2161
2162 self->mypid = getpid();
2163 ASSERT_GT(self->mypid, 0);
2164 ASSERT_EQ(self->mytid, self->mypid);
2165
2166 self->parent = getppid();
2167 ASSERT_GT(self->parent, 0);
2168 ASSERT_NE(self->parent, self->mypid);
2169
2170 /* Launch tracer. */
2171 self->tracer = setup_trace_fixture(_metadata,
2172 variant->use_ptrace ? tracer_ptrace
2173 : tracer_seccomp,
2174 self, variant->use_ptrace);
2175
2176 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2177 ASSERT_EQ(0, ret);
2178
2179 /* Do not install seccomp rewrite filters, as we'll use ptrace instead. */
2180 if (variant->use_ptrace)
2181 return;
2182
2183 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2184 ASSERT_EQ(0, ret);
2185 }
2186
FIXTURE_TEARDOWN(TRACE_syscall)2187 FIXTURE_TEARDOWN(TRACE_syscall)
2188 {
2189 teardown_trace_fixture(_metadata, self->tracer);
2190 }
2191
TEST(negative_ENOSYS)2192 TEST(negative_ENOSYS)
2193 {
2194 #if defined(__arm__)
2195 SKIP(return, "arm32 does not support calling syscall -1");
2196 #endif
2197 /*
2198 * There should be no difference between an "internal" skip
2199 * and userspace asking for syscall "-1".
2200 */
2201 errno = 0;
2202 EXPECT_EQ(-1, syscall(-1));
2203 EXPECT_EQ(errno, ENOSYS);
2204 /* And no difference for "still not valid but not -1". */
2205 errno = 0;
2206 EXPECT_EQ(-1, syscall(-101));
2207 EXPECT_EQ(errno, ENOSYS);
2208 }
2209
TEST_F(TRACE_syscall,negative_ENOSYS)2210 TEST_F(TRACE_syscall, negative_ENOSYS)
2211 {
2212 negative_ENOSYS(_metadata);
2213 }
2214
TEST_F(TRACE_syscall,syscall_allowed)2215 TEST_F(TRACE_syscall, syscall_allowed)
2216 {
2217 /* getppid works as expected (no changes). */
2218 EXPECT_EQ(self->parent, syscall(__NR_getppid));
2219 EXPECT_NE(self->mypid, syscall(__NR_getppid));
2220 }
2221
TEST_F(TRACE_syscall,syscall_redirected)2222 TEST_F(TRACE_syscall, syscall_redirected)
2223 {
2224 /* getpid has been redirected to getppid as expected. */
2225 EXPECT_EQ(self->parent, syscall(__NR_getpid));
2226 EXPECT_NE(self->mypid, syscall(__NR_getpid));
2227 }
2228
TEST_F(TRACE_syscall,syscall_errno)2229 TEST_F(TRACE_syscall, syscall_errno)
2230 {
2231 /* Tracer should skip the open syscall, resulting in ESRCH. */
2232 EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
2233 }
2234
TEST_F(TRACE_syscall,syscall_faked)2235 TEST_F(TRACE_syscall, syscall_faked)
2236 {
2237 /* Tracer skips the gettid syscall and store altered return value. */
2238 EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
2239 }
2240
TEST_F_SIGNAL(TRACE_syscall,kill_immediate,SIGSYS)2241 TEST_F_SIGNAL(TRACE_syscall, kill_immediate, SIGSYS)
2242 {
2243 struct sock_filter filter[] = {
2244 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2245 offsetof(struct seccomp_data, nr)),
2246 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_mknodat, 0, 1),
2247 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
2248 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2249 };
2250 struct sock_fprog prog = {
2251 .len = (unsigned short)ARRAY_SIZE(filter),
2252 .filter = filter,
2253 };
2254 long ret;
2255
2256 /* Install "kill on mknodat" filter. */
2257 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2258 ASSERT_EQ(0, ret);
2259
2260 /* This should immediately die with SIGSYS, regardless of tracer. */
2261 EXPECT_EQ(-1, syscall(__NR_mknodat, -1, NULL, 0, 0));
2262 }
2263
TEST_F(TRACE_syscall,skip_after)2264 TEST_F(TRACE_syscall, skip_after)
2265 {
2266 struct sock_filter filter[] = {
2267 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2268 offsetof(struct seccomp_data, nr)),
2269 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2270 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
2271 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2272 };
2273 struct sock_fprog prog = {
2274 .len = (unsigned short)ARRAY_SIZE(filter),
2275 .filter = filter,
2276 };
2277 long ret;
2278
2279 /* Install additional "errno on getppid" filter. */
2280 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2281 ASSERT_EQ(0, ret);
2282
2283 /* Tracer will redirect getpid to getppid, and we should see EPERM. */
2284 errno = 0;
2285 EXPECT_EQ(-1, syscall(__NR_getpid));
2286 EXPECT_EQ(EPERM, errno);
2287 }
2288
TEST_F_SIGNAL(TRACE_syscall,kill_after,SIGSYS)2289 TEST_F_SIGNAL(TRACE_syscall, kill_after, SIGSYS)
2290 {
2291 struct sock_filter filter[] = {
2292 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2293 offsetof(struct seccomp_data, nr)),
2294 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
2295 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2296 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2297 };
2298 struct sock_fprog prog = {
2299 .len = (unsigned short)ARRAY_SIZE(filter),
2300 .filter = filter,
2301 };
2302 long ret;
2303
2304 /* Install additional "death on getppid" filter. */
2305 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2306 ASSERT_EQ(0, ret);
2307
2308 /* Tracer will redirect getpid to getppid, and we should die. */
2309 EXPECT_NE(self->mypid, syscall(__NR_getpid));
2310 }
2311
TEST(seccomp_syscall)2312 TEST(seccomp_syscall)
2313 {
2314 struct sock_filter filter[] = {
2315 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2316 };
2317 struct sock_fprog prog = {
2318 .len = (unsigned short)ARRAY_SIZE(filter),
2319 .filter = filter,
2320 };
2321 long ret;
2322
2323 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2324 ASSERT_EQ(0, ret) {
2325 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2326 }
2327
2328 /* Reject insane operation. */
2329 ret = seccomp(-1, 0, &prog);
2330 ASSERT_NE(ENOSYS, errno) {
2331 TH_LOG("Kernel does not support seccomp syscall!");
2332 }
2333 EXPECT_EQ(EINVAL, errno) {
2334 TH_LOG("Did not reject crazy op value!");
2335 }
2336
2337 /* Reject strict with flags or pointer. */
2338 ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
2339 EXPECT_EQ(EINVAL, errno) {
2340 TH_LOG("Did not reject mode strict with flags!");
2341 }
2342 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
2343 EXPECT_EQ(EINVAL, errno) {
2344 TH_LOG("Did not reject mode strict with uargs!");
2345 }
2346
2347 /* Reject insane args for filter. */
2348 ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
2349 EXPECT_EQ(EINVAL, errno) {
2350 TH_LOG("Did not reject crazy filter flags!");
2351 }
2352 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
2353 EXPECT_EQ(EFAULT, errno) {
2354 TH_LOG("Did not reject NULL filter!");
2355 }
2356
2357 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2358 EXPECT_EQ(0, errno) {
2359 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
2360 strerror(errno));
2361 }
2362 }
2363
TEST(seccomp_syscall_mode_lock)2364 TEST(seccomp_syscall_mode_lock)
2365 {
2366 struct sock_filter filter[] = {
2367 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2368 };
2369 struct sock_fprog prog = {
2370 .len = (unsigned short)ARRAY_SIZE(filter),
2371 .filter = filter,
2372 };
2373 long ret;
2374
2375 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2376 ASSERT_EQ(0, ret) {
2377 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2378 }
2379
2380 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2381 ASSERT_NE(ENOSYS, errno) {
2382 TH_LOG("Kernel does not support seccomp syscall!");
2383 }
2384 EXPECT_EQ(0, ret) {
2385 TH_LOG("Could not install filter!");
2386 }
2387
2388 /* Make sure neither entry point will switch to strict. */
2389 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
2390 EXPECT_EQ(EINVAL, errno) {
2391 TH_LOG("Switched to mode strict!");
2392 }
2393
2394 ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
2395 EXPECT_EQ(EINVAL, errno) {
2396 TH_LOG("Switched to mode strict!");
2397 }
2398 }
2399
2400 /*
2401 * Test detection of known and unknown filter flags. Userspace needs to be able
2402 * to check if a filter flag is supported by the current kernel and a good way
2403 * of doing that is by attempting to enter filter mode, with the flag bit in
2404 * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
2405 * that the flag is valid and EINVAL indicates that the flag is invalid.
2406 */
TEST(detect_seccomp_filter_flags)2407 TEST(detect_seccomp_filter_flags)
2408 {
2409 unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
2410 SECCOMP_FILTER_FLAG_LOG,
2411 SECCOMP_FILTER_FLAG_SPEC_ALLOW,
2412 SECCOMP_FILTER_FLAG_NEW_LISTENER,
2413 SECCOMP_FILTER_FLAG_TSYNC_ESRCH };
2414 unsigned int exclusive[] = {
2415 SECCOMP_FILTER_FLAG_TSYNC,
2416 SECCOMP_FILTER_FLAG_NEW_LISTENER };
2417 unsigned int flag, all_flags, exclusive_mask;
2418 int i;
2419 long ret;
2420
2421 /* Test detection of individual known-good filter flags */
2422 for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
2423 int bits = 0;
2424
2425 flag = flags[i];
2426 /* Make sure the flag is a single bit! */
2427 while (flag) {
2428 if (flag & 0x1)
2429 bits ++;
2430 flag >>= 1;
2431 }
2432 ASSERT_EQ(1, bits);
2433 flag = flags[i];
2434
2435 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2436 ASSERT_NE(ENOSYS, errno) {
2437 TH_LOG("Kernel does not support seccomp syscall!");
2438 }
2439 EXPECT_EQ(-1, ret);
2440 EXPECT_EQ(EFAULT, errno) {
2441 TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
2442 flag);
2443 }
2444
2445 all_flags |= flag;
2446 }
2447
2448 /*
2449 * Test detection of all known-good filter flags combined. But
2450 * for the exclusive flags we need to mask them out and try them
2451 * individually for the "all flags" testing.
2452 */
2453 exclusive_mask = 0;
2454 for (i = 0; i < ARRAY_SIZE(exclusive); i++)
2455 exclusive_mask |= exclusive[i];
2456 for (i = 0; i < ARRAY_SIZE(exclusive); i++) {
2457 flag = all_flags & ~exclusive_mask;
2458 flag |= exclusive[i];
2459
2460 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2461 EXPECT_EQ(-1, ret);
2462 EXPECT_EQ(EFAULT, errno) {
2463 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
2464 flag);
2465 }
2466 }
2467
2468 /* Test detection of an unknown filter flags, without exclusives. */
2469 flag = -1;
2470 flag &= ~exclusive_mask;
2471 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2472 EXPECT_EQ(-1, ret);
2473 EXPECT_EQ(EINVAL, errno) {
2474 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
2475 flag);
2476 }
2477
2478 /*
2479 * Test detection of an unknown filter flag that may simply need to be
2480 * added to this test
2481 */
2482 flag = flags[ARRAY_SIZE(flags) - 1] << 1;
2483 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2484 EXPECT_EQ(-1, ret);
2485 EXPECT_EQ(EINVAL, errno) {
2486 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?",
2487 flag);
2488 }
2489 }
2490
TEST(TSYNC_first)2491 TEST(TSYNC_first)
2492 {
2493 struct sock_filter filter[] = {
2494 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2495 };
2496 struct sock_fprog prog = {
2497 .len = (unsigned short)ARRAY_SIZE(filter),
2498 .filter = filter,
2499 };
2500 long ret;
2501
2502 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2503 ASSERT_EQ(0, ret) {
2504 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2505 }
2506
2507 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2508 &prog);
2509 ASSERT_NE(ENOSYS, errno) {
2510 TH_LOG("Kernel does not support seccomp syscall!");
2511 }
2512 EXPECT_EQ(0, ret) {
2513 TH_LOG("Could not install initial filter with TSYNC!");
2514 }
2515 }
2516
2517 #define TSYNC_SIBLINGS 2
2518 struct tsync_sibling {
2519 pthread_t tid;
2520 pid_t system_tid;
2521 sem_t *started;
2522 pthread_cond_t *cond;
2523 pthread_mutex_t *mutex;
2524 int diverge;
2525 int num_waits;
2526 struct sock_fprog *prog;
2527 struct __test_metadata *metadata;
2528 };
2529
2530 /*
2531 * To avoid joining joined threads (which is not allowed by Bionic),
2532 * make sure we both successfully join and clear the tid to skip a
2533 * later join attempt during fixture teardown. Any remaining threads
2534 * will be directly killed during teardown.
2535 */
2536 #define PTHREAD_JOIN(tid, status) \
2537 do { \
2538 int _rc = pthread_join(tid, status); \
2539 if (_rc) { \
2540 TH_LOG("pthread_join of tid %u failed: %d\n", \
2541 (unsigned int)tid, _rc); \
2542 } else { \
2543 tid = 0; \
2544 } \
2545 } while (0)
2546
FIXTURE(TSYNC)2547 FIXTURE(TSYNC) {
2548 struct sock_fprog root_prog, apply_prog;
2549 struct tsync_sibling sibling[TSYNC_SIBLINGS];
2550 sem_t started;
2551 pthread_cond_t cond;
2552 pthread_mutex_t mutex;
2553 int sibling_count;
2554 };
2555
FIXTURE_SETUP(TSYNC)2556 FIXTURE_SETUP(TSYNC)
2557 {
2558 struct sock_filter root_filter[] = {
2559 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2560 };
2561 struct sock_filter apply_filter[] = {
2562 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2563 offsetof(struct seccomp_data, nr)),
2564 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
2565 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2566 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2567 };
2568
2569 memset(&self->root_prog, 0, sizeof(self->root_prog));
2570 memset(&self->apply_prog, 0, sizeof(self->apply_prog));
2571 memset(&self->sibling, 0, sizeof(self->sibling));
2572 self->root_prog.filter = malloc(sizeof(root_filter));
2573 ASSERT_NE(NULL, self->root_prog.filter);
2574 memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
2575 self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
2576
2577 self->apply_prog.filter = malloc(sizeof(apply_filter));
2578 ASSERT_NE(NULL, self->apply_prog.filter);
2579 memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
2580 self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
2581
2582 self->sibling_count = 0;
2583 pthread_mutex_init(&self->mutex, NULL);
2584 pthread_cond_init(&self->cond, NULL);
2585 sem_init(&self->started, 0, 0);
2586 self->sibling[0].tid = 0;
2587 self->sibling[0].cond = &self->cond;
2588 self->sibling[0].started = &self->started;
2589 self->sibling[0].mutex = &self->mutex;
2590 self->sibling[0].diverge = 0;
2591 self->sibling[0].num_waits = 1;
2592 self->sibling[0].prog = &self->root_prog;
2593 self->sibling[0].metadata = _metadata;
2594 self->sibling[1].tid = 0;
2595 self->sibling[1].cond = &self->cond;
2596 self->sibling[1].started = &self->started;
2597 self->sibling[1].mutex = &self->mutex;
2598 self->sibling[1].diverge = 0;
2599 self->sibling[1].prog = &self->root_prog;
2600 self->sibling[1].num_waits = 1;
2601 self->sibling[1].metadata = _metadata;
2602 }
2603
FIXTURE_TEARDOWN(TSYNC)2604 FIXTURE_TEARDOWN(TSYNC)
2605 {
2606 int sib = 0;
2607
2608 if (self->root_prog.filter)
2609 free(self->root_prog.filter);
2610 if (self->apply_prog.filter)
2611 free(self->apply_prog.filter);
2612
2613 for ( ; sib < self->sibling_count; ++sib) {
2614 struct tsync_sibling *s = &self->sibling[sib];
2615
2616 if (!s->tid)
2617 continue;
2618 /*
2619 * If a thread is still running, it may be stuck, so hit
2620 * it over the head really hard.
2621 */
2622 pthread_kill(s->tid, 9);
2623 }
2624 pthread_mutex_destroy(&self->mutex);
2625 pthread_cond_destroy(&self->cond);
2626 sem_destroy(&self->started);
2627 }
2628
tsync_sibling(void * data)2629 void *tsync_sibling(void *data)
2630 {
2631 long ret = 0;
2632 struct tsync_sibling *me = data;
2633
2634 me->system_tid = syscall(__NR_gettid);
2635
2636 pthread_mutex_lock(me->mutex);
2637 if (me->diverge) {
2638 /* Just re-apply the root prog to fork the tree */
2639 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
2640 me->prog, 0, 0);
2641 }
2642 sem_post(me->started);
2643 /* Return outside of started so parent notices failures. */
2644 if (ret) {
2645 pthread_mutex_unlock(me->mutex);
2646 return (void *)SIBLING_EXIT_FAILURE;
2647 }
2648 do {
2649 pthread_cond_wait(me->cond, me->mutex);
2650 me->num_waits = me->num_waits - 1;
2651 } while (me->num_waits);
2652 pthread_mutex_unlock(me->mutex);
2653
2654 ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
2655 if (!ret)
2656 return (void *)SIBLING_EXIT_NEWPRIVS;
2657 read(-1, NULL, 0);
2658 return (void *)SIBLING_EXIT_UNKILLED;
2659 }
2660
tsync_start_sibling(struct tsync_sibling * sibling)2661 void tsync_start_sibling(struct tsync_sibling *sibling)
2662 {
2663 pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
2664 }
2665
TEST_F(TSYNC,siblings_fail_prctl)2666 TEST_F(TSYNC, siblings_fail_prctl)
2667 {
2668 long ret;
2669 void *status;
2670 struct sock_filter filter[] = {
2671 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2672 offsetof(struct seccomp_data, nr)),
2673 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
2674 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
2675 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2676 };
2677 struct sock_fprog prog = {
2678 .len = (unsigned short)ARRAY_SIZE(filter),
2679 .filter = filter,
2680 };
2681
2682 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2683 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2684 }
2685
2686 /* Check prctl failure detection by requesting sib 0 diverge. */
2687 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2688 ASSERT_NE(ENOSYS, errno) {
2689 TH_LOG("Kernel does not support seccomp syscall!");
2690 }
2691 ASSERT_EQ(0, ret) {
2692 TH_LOG("setting filter failed");
2693 }
2694
2695 self->sibling[0].diverge = 1;
2696 tsync_start_sibling(&self->sibling[0]);
2697 tsync_start_sibling(&self->sibling[1]);
2698
2699 while (self->sibling_count < TSYNC_SIBLINGS) {
2700 sem_wait(&self->started);
2701 self->sibling_count++;
2702 }
2703
2704 /* Signal the threads to clean up*/
2705 pthread_mutex_lock(&self->mutex);
2706 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2707 TH_LOG("cond broadcast non-zero");
2708 }
2709 pthread_mutex_unlock(&self->mutex);
2710
2711 /* Ensure diverging sibling failed to call prctl. */
2712 PTHREAD_JOIN(self->sibling[0].tid, &status);
2713 EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
2714 PTHREAD_JOIN(self->sibling[1].tid, &status);
2715 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2716 }
2717
TEST_F(TSYNC,two_siblings_with_ancestor)2718 TEST_F(TSYNC, two_siblings_with_ancestor)
2719 {
2720 long ret;
2721 void *status;
2722
2723 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2724 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2725 }
2726
2727 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2728 ASSERT_NE(ENOSYS, errno) {
2729 TH_LOG("Kernel does not support seccomp syscall!");
2730 }
2731 ASSERT_EQ(0, ret) {
2732 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2733 }
2734 tsync_start_sibling(&self->sibling[0]);
2735 tsync_start_sibling(&self->sibling[1]);
2736
2737 while (self->sibling_count < TSYNC_SIBLINGS) {
2738 sem_wait(&self->started);
2739 self->sibling_count++;
2740 }
2741
2742 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2743 &self->apply_prog);
2744 ASSERT_EQ(0, ret) {
2745 TH_LOG("Could install filter on all threads!");
2746 }
2747 /* Tell the siblings to test the policy */
2748 pthread_mutex_lock(&self->mutex);
2749 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2750 TH_LOG("cond broadcast non-zero");
2751 }
2752 pthread_mutex_unlock(&self->mutex);
2753 /* Ensure they are both killed and don't exit cleanly. */
2754 PTHREAD_JOIN(self->sibling[0].tid, &status);
2755 EXPECT_EQ(0x0, (long)status);
2756 PTHREAD_JOIN(self->sibling[1].tid, &status);
2757 EXPECT_EQ(0x0, (long)status);
2758 }
2759
TEST_F(TSYNC,two_sibling_want_nnp)2760 TEST_F(TSYNC, two_sibling_want_nnp)
2761 {
2762 void *status;
2763
2764 /* start siblings before any prctl() operations */
2765 tsync_start_sibling(&self->sibling[0]);
2766 tsync_start_sibling(&self->sibling[1]);
2767 while (self->sibling_count < TSYNC_SIBLINGS) {
2768 sem_wait(&self->started);
2769 self->sibling_count++;
2770 }
2771
2772 /* Tell the siblings to test no policy */
2773 pthread_mutex_lock(&self->mutex);
2774 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2775 TH_LOG("cond broadcast non-zero");
2776 }
2777 pthread_mutex_unlock(&self->mutex);
2778
2779 /* Ensure they are both upset about lacking nnp. */
2780 PTHREAD_JOIN(self->sibling[0].tid, &status);
2781 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2782 PTHREAD_JOIN(self->sibling[1].tid, &status);
2783 EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2784 }
2785
TEST_F(TSYNC,two_siblings_with_no_filter)2786 TEST_F(TSYNC, two_siblings_with_no_filter)
2787 {
2788 long ret;
2789 void *status;
2790
2791 /* start siblings before any prctl() operations */
2792 tsync_start_sibling(&self->sibling[0]);
2793 tsync_start_sibling(&self->sibling[1]);
2794 while (self->sibling_count < TSYNC_SIBLINGS) {
2795 sem_wait(&self->started);
2796 self->sibling_count++;
2797 }
2798
2799 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2800 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2801 }
2802
2803 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2804 &self->apply_prog);
2805 ASSERT_NE(ENOSYS, errno) {
2806 TH_LOG("Kernel does not support seccomp syscall!");
2807 }
2808 ASSERT_EQ(0, ret) {
2809 TH_LOG("Could install filter on all threads!");
2810 }
2811
2812 /* Tell the siblings to test the policy */
2813 pthread_mutex_lock(&self->mutex);
2814 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2815 TH_LOG("cond broadcast non-zero");
2816 }
2817 pthread_mutex_unlock(&self->mutex);
2818
2819 /* Ensure they are both killed and don't exit cleanly. */
2820 PTHREAD_JOIN(self->sibling[0].tid, &status);
2821 EXPECT_EQ(0x0, (long)status);
2822 PTHREAD_JOIN(self->sibling[1].tid, &status);
2823 EXPECT_EQ(0x0, (long)status);
2824 }
2825
TEST_F(TSYNC,two_siblings_with_one_divergence)2826 TEST_F(TSYNC, two_siblings_with_one_divergence)
2827 {
2828 long ret;
2829 void *status;
2830
2831 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2832 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2833 }
2834
2835 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2836 ASSERT_NE(ENOSYS, errno) {
2837 TH_LOG("Kernel does not support seccomp syscall!");
2838 }
2839 ASSERT_EQ(0, ret) {
2840 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2841 }
2842 self->sibling[0].diverge = 1;
2843 tsync_start_sibling(&self->sibling[0]);
2844 tsync_start_sibling(&self->sibling[1]);
2845
2846 while (self->sibling_count < TSYNC_SIBLINGS) {
2847 sem_wait(&self->started);
2848 self->sibling_count++;
2849 }
2850
2851 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2852 &self->apply_prog);
2853 ASSERT_EQ(self->sibling[0].system_tid, ret) {
2854 TH_LOG("Did not fail on diverged sibling.");
2855 }
2856
2857 /* Wake the threads */
2858 pthread_mutex_lock(&self->mutex);
2859 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2860 TH_LOG("cond broadcast non-zero");
2861 }
2862 pthread_mutex_unlock(&self->mutex);
2863
2864 /* Ensure they are both unkilled. */
2865 PTHREAD_JOIN(self->sibling[0].tid, &status);
2866 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2867 PTHREAD_JOIN(self->sibling[1].tid, &status);
2868 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2869 }
2870
TEST_F(TSYNC,two_siblings_with_one_divergence_no_tid_in_err)2871 TEST_F(TSYNC, two_siblings_with_one_divergence_no_tid_in_err)
2872 {
2873 long ret, flags;
2874 void *status;
2875
2876 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2877 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2878 }
2879
2880 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2881 ASSERT_NE(ENOSYS, errno) {
2882 TH_LOG("Kernel does not support seccomp syscall!");
2883 }
2884 ASSERT_EQ(0, ret) {
2885 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2886 }
2887 self->sibling[0].diverge = 1;
2888 tsync_start_sibling(&self->sibling[0]);
2889 tsync_start_sibling(&self->sibling[1]);
2890
2891 while (self->sibling_count < TSYNC_SIBLINGS) {
2892 sem_wait(&self->started);
2893 self->sibling_count++;
2894 }
2895
2896 flags = SECCOMP_FILTER_FLAG_TSYNC | \
2897 SECCOMP_FILTER_FLAG_TSYNC_ESRCH;
2898 ret = seccomp(SECCOMP_SET_MODE_FILTER, flags, &self->apply_prog);
2899 ASSERT_EQ(ESRCH, errno) {
2900 TH_LOG("Did not return ESRCH for diverged sibling.");
2901 }
2902 ASSERT_EQ(-1, ret) {
2903 TH_LOG("Did not fail on diverged sibling.");
2904 }
2905
2906 /* Wake the threads */
2907 pthread_mutex_lock(&self->mutex);
2908 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2909 TH_LOG("cond broadcast non-zero");
2910 }
2911 pthread_mutex_unlock(&self->mutex);
2912
2913 /* Ensure they are both unkilled. */
2914 PTHREAD_JOIN(self->sibling[0].tid, &status);
2915 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2916 PTHREAD_JOIN(self->sibling[1].tid, &status);
2917 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2918 }
2919
TEST_F(TSYNC,two_siblings_not_under_filter)2920 TEST_F(TSYNC, two_siblings_not_under_filter)
2921 {
2922 long ret, sib;
2923 void *status;
2924 struct timespec delay = { .tv_nsec = 100000000 };
2925
2926 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2927 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2928 }
2929
2930 /*
2931 * Sibling 0 will have its own seccomp policy
2932 * and Sibling 1 will not be under seccomp at
2933 * all. Sibling 1 will enter seccomp and 0
2934 * will cause failure.
2935 */
2936 self->sibling[0].diverge = 1;
2937 tsync_start_sibling(&self->sibling[0]);
2938 tsync_start_sibling(&self->sibling[1]);
2939
2940 while (self->sibling_count < TSYNC_SIBLINGS) {
2941 sem_wait(&self->started);
2942 self->sibling_count++;
2943 }
2944
2945 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2946 ASSERT_NE(ENOSYS, errno) {
2947 TH_LOG("Kernel does not support seccomp syscall!");
2948 }
2949 ASSERT_EQ(0, ret) {
2950 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2951 }
2952
2953 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2954 &self->apply_prog);
2955 ASSERT_EQ(ret, self->sibling[0].system_tid) {
2956 TH_LOG("Did not fail on diverged sibling.");
2957 }
2958 sib = 1;
2959 if (ret == self->sibling[0].system_tid)
2960 sib = 0;
2961
2962 pthread_mutex_lock(&self->mutex);
2963
2964 /* Increment the other siblings num_waits so we can clean up
2965 * the one we just saw.
2966 */
2967 self->sibling[!sib].num_waits += 1;
2968
2969 /* Signal the thread to clean up*/
2970 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2971 TH_LOG("cond broadcast non-zero");
2972 }
2973 pthread_mutex_unlock(&self->mutex);
2974 PTHREAD_JOIN(self->sibling[sib].tid, &status);
2975 EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2976 /* Poll for actual task death. pthread_join doesn't guarantee it. */
2977 while (!kill(self->sibling[sib].system_tid, 0))
2978 nanosleep(&delay, NULL);
2979 /* Switch to the remaining sibling */
2980 sib = !sib;
2981
2982 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2983 &self->apply_prog);
2984 ASSERT_EQ(0, ret) {
2985 TH_LOG("Expected the remaining sibling to sync");
2986 };
2987
2988 pthread_mutex_lock(&self->mutex);
2989
2990 /* If remaining sibling didn't have a chance to wake up during
2991 * the first broadcast, manually reduce the num_waits now.
2992 */
2993 if (self->sibling[sib].num_waits > 1)
2994 self->sibling[sib].num_waits = 1;
2995 ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2996 TH_LOG("cond broadcast non-zero");
2997 }
2998 pthread_mutex_unlock(&self->mutex);
2999 PTHREAD_JOIN(self->sibling[sib].tid, &status);
3000 EXPECT_EQ(0, (long)status);
3001 /* Poll for actual task death. pthread_join doesn't guarantee it. */
3002 while (!kill(self->sibling[sib].system_tid, 0))
3003 nanosleep(&delay, NULL);
3004
3005 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
3006 &self->apply_prog);
3007 ASSERT_EQ(0, ret); /* just us chickens */
3008 }
3009
3010 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
TEST(syscall_restart)3011 TEST(syscall_restart)
3012 {
3013 long ret;
3014 unsigned long msg;
3015 pid_t child_pid;
3016 int pipefd[2];
3017 int status;
3018 siginfo_t info = { };
3019 struct sock_filter filter[] = {
3020 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
3021 offsetof(struct seccomp_data, nr)),
3022
3023 #ifdef __NR_sigreturn
3024 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 7, 0),
3025 #endif
3026 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 6, 0),
3027 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 5, 0),
3028 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 4, 0),
3029 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 5, 0),
3030 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_clock_nanosleep, 4, 0),
3031 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
3032
3033 /* Allow __NR_write for easy logging. */
3034 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
3035 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3036 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
3037 /* The nanosleep jump target. */
3038 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
3039 /* The restart_syscall jump target. */
3040 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
3041 };
3042 struct sock_fprog prog = {
3043 .len = (unsigned short)ARRAY_SIZE(filter),
3044 .filter = filter,
3045 };
3046 #if defined(__arm__)
3047 struct utsname utsbuf;
3048 #endif
3049
3050 ASSERT_EQ(0, pipe(pipefd));
3051
3052 child_pid = fork();
3053 ASSERT_LE(0, child_pid);
3054 if (child_pid == 0) {
3055 /* Child uses EXPECT not ASSERT to deliver status correctly. */
3056 char buf = ' ';
3057 struct timespec timeout = { };
3058
3059 /* Attach parent as tracer and stop. */
3060 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
3061 EXPECT_EQ(0, raise(SIGSTOP));
3062
3063 EXPECT_EQ(0, close(pipefd[1]));
3064
3065 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
3066 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3067 }
3068
3069 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
3070 EXPECT_EQ(0, ret) {
3071 TH_LOG("Failed to install filter!");
3072 }
3073
3074 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
3075 TH_LOG("Failed to read() sync from parent");
3076 }
3077 EXPECT_EQ('.', buf) {
3078 TH_LOG("Failed to get sync data from read()");
3079 }
3080
3081 /* Start nanosleep to be interrupted. */
3082 timeout.tv_sec = 1;
3083 errno = 0;
3084 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
3085 TH_LOG("Call to nanosleep() failed (errno %d: %s)",
3086 errno, strerror(errno));
3087 }
3088
3089 /* Read final sync from parent. */
3090 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
3091 TH_LOG("Failed final read() from parent");
3092 }
3093 EXPECT_EQ('!', buf) {
3094 TH_LOG("Failed to get final data from read()");
3095 }
3096
3097 /* Directly report the status of our test harness results. */
3098 syscall(__NR_exit, _metadata->exit_code);
3099 }
3100 EXPECT_EQ(0, close(pipefd[0]));
3101
3102 /* Attach to child, setup options, and release. */
3103 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3104 ASSERT_EQ(true, WIFSTOPPED(status));
3105 ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
3106 PTRACE_O_TRACESECCOMP));
3107 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
3108 ASSERT_EQ(1, write(pipefd[1], ".", 1));
3109
3110 /* Wait for nanosleep() to start. */
3111 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3112 ASSERT_EQ(true, WIFSTOPPED(status));
3113 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
3114 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
3115 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
3116 ASSERT_EQ(0x100, msg);
3117 ret = get_syscall(_metadata, child_pid);
3118 EXPECT_TRUE(ret == __NR_nanosleep || ret == __NR_clock_nanosleep);
3119
3120 /* Might as well check siginfo for sanity while we're here. */
3121 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
3122 ASSERT_EQ(SIGTRAP, info.si_signo);
3123 ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
3124 EXPECT_EQ(0, info.si_errno);
3125 EXPECT_EQ(getuid(), info.si_uid);
3126 /* Verify signal delivery came from child (seccomp-triggered). */
3127 EXPECT_EQ(child_pid, info.si_pid);
3128
3129 /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
3130 ASSERT_EQ(0, kill(child_pid, SIGSTOP));
3131 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
3132 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3133 ASSERT_EQ(true, WIFSTOPPED(status));
3134 ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
3135 ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
3136 /*
3137 * There is no siginfo on SIGSTOP any more, so we can't verify
3138 * signal delivery came from parent now (getpid() == info.si_pid).
3139 * https://lkml.kernel.org/r/CAGXu5jJaZAOzP1qFz66tYrtbuywqb+UN2SOA1VLHpCCOiYvYeg@mail.gmail.com
3140 * At least verify the SIGSTOP via PTRACE_GETSIGINFO.
3141 */
3142 EXPECT_EQ(SIGSTOP, info.si_signo);
3143
3144 /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
3145 ASSERT_EQ(0, kill(child_pid, SIGCONT));
3146 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
3147 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3148 ASSERT_EQ(true, WIFSTOPPED(status));
3149 ASSERT_EQ(SIGCONT, WSTOPSIG(status));
3150 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
3151
3152 /* Wait for restart_syscall() to start. */
3153 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3154 ASSERT_EQ(true, WIFSTOPPED(status));
3155 ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
3156 ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
3157 ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
3158
3159 ASSERT_EQ(0x200, msg);
3160 ret = get_syscall(_metadata, child_pid);
3161 #if defined(__arm__)
3162 /*
3163 * FIXME:
3164 * - native ARM registers do NOT expose true syscall.
3165 * - compat ARM registers on ARM64 DO expose true syscall.
3166 */
3167 ASSERT_EQ(0, uname(&utsbuf));
3168 if (strncmp(utsbuf.machine, "arm", 3) == 0) {
3169 EXPECT_EQ(__NR_nanosleep, ret);
3170 } else
3171 #endif
3172 {
3173 EXPECT_EQ(__NR_restart_syscall, ret);
3174 }
3175
3176 /* Write again to end test. */
3177 ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
3178 ASSERT_EQ(1, write(pipefd[1], "!", 1));
3179 EXPECT_EQ(0, close(pipefd[1]));
3180
3181 ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
3182 if (WIFSIGNALED(status) || WEXITSTATUS(status))
3183 _metadata->exit_code = KSFT_FAIL;
3184 }
3185
TEST_SIGNAL(filter_flag_log,SIGSYS)3186 TEST_SIGNAL(filter_flag_log, SIGSYS)
3187 {
3188 struct sock_filter allow_filter[] = {
3189 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3190 };
3191 struct sock_filter kill_filter[] = {
3192 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
3193 offsetof(struct seccomp_data, nr)),
3194 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
3195 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
3196 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3197 };
3198 struct sock_fprog allow_prog = {
3199 .len = (unsigned short)ARRAY_SIZE(allow_filter),
3200 .filter = allow_filter,
3201 };
3202 struct sock_fprog kill_prog = {
3203 .len = (unsigned short)ARRAY_SIZE(kill_filter),
3204 .filter = kill_filter,
3205 };
3206 long ret;
3207 pid_t parent = getppid();
3208
3209 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3210 ASSERT_EQ(0, ret);
3211
3212 /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
3213 ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
3214 &allow_prog);
3215 ASSERT_NE(ENOSYS, errno) {
3216 TH_LOG("Kernel does not support seccomp syscall!");
3217 }
3218 EXPECT_NE(0, ret) {
3219 TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
3220 }
3221 EXPECT_EQ(EINVAL, errno) {
3222 TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
3223 }
3224
3225 /* Verify that a simple, permissive filter can be added with no flags */
3226 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
3227 EXPECT_EQ(0, ret);
3228
3229 /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
3230 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
3231 &allow_prog);
3232 ASSERT_NE(EINVAL, errno) {
3233 TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
3234 }
3235 EXPECT_EQ(0, ret);
3236
3237 /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
3238 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
3239 &kill_prog);
3240 EXPECT_EQ(0, ret);
3241
3242 EXPECT_EQ(parent, syscall(__NR_getppid));
3243 /* getpid() should never return. */
3244 EXPECT_EQ(0, syscall(__NR_getpid));
3245 }
3246
TEST(get_action_avail)3247 TEST(get_action_avail)
3248 {
3249 __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
3250 SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
3251 SECCOMP_RET_LOG, SECCOMP_RET_ALLOW };
3252 __u32 unknown_action = 0x10000000U;
3253 int i;
3254 long ret;
3255
3256 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
3257 ASSERT_NE(ENOSYS, errno) {
3258 TH_LOG("Kernel does not support seccomp syscall!");
3259 }
3260 ASSERT_NE(EINVAL, errno) {
3261 TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
3262 }
3263 EXPECT_EQ(ret, 0);
3264
3265 for (i = 0; i < ARRAY_SIZE(actions); i++) {
3266 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
3267 EXPECT_EQ(ret, 0) {
3268 TH_LOG("Expected action (0x%X) not available!",
3269 actions[i]);
3270 }
3271 }
3272
3273 /* Check that an unknown action is handled properly (EOPNOTSUPP) */
3274 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
3275 EXPECT_EQ(ret, -1);
3276 EXPECT_EQ(errno, EOPNOTSUPP);
3277 }
3278
TEST(get_metadata)3279 TEST(get_metadata)
3280 {
3281 pid_t pid;
3282 int pipefd[2];
3283 char buf;
3284 struct seccomp_metadata md;
3285 long ret;
3286
3287 /* Only real root can get metadata. */
3288 if (geteuid()) {
3289 SKIP(return, "get_metadata requires real root");
3290 return;
3291 }
3292
3293 ASSERT_EQ(0, pipe(pipefd));
3294
3295 pid = fork();
3296 ASSERT_GE(pid, 0);
3297 if (pid == 0) {
3298 struct sock_filter filter[] = {
3299 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3300 };
3301 struct sock_fprog prog = {
3302 .len = (unsigned short)ARRAY_SIZE(filter),
3303 .filter = filter,
3304 };
3305
3306 /* one with log, one without */
3307 EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
3308 SECCOMP_FILTER_FLAG_LOG, &prog));
3309 EXPECT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));
3310
3311 EXPECT_EQ(0, close(pipefd[0]));
3312 ASSERT_EQ(1, write(pipefd[1], "1", 1));
3313 ASSERT_EQ(0, close(pipefd[1]));
3314
3315 while (1)
3316 sleep(100);
3317 }
3318
3319 ASSERT_EQ(0, close(pipefd[1]));
3320 ASSERT_EQ(1, read(pipefd[0], &buf, 1));
3321
3322 ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
3323 ASSERT_EQ(pid, waitpid(pid, NULL, 0));
3324
3325 /* Past here must not use ASSERT or child process is never killed. */
3326
3327 md.filter_off = 0;
3328 errno = 0;
3329 ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
3330 EXPECT_EQ(sizeof(md), ret) {
3331 if (errno == EINVAL)
3332 SKIP(goto skip, "Kernel does not support PTRACE_SECCOMP_GET_METADATA (missing CONFIG_CHECKPOINT_RESTORE?)");
3333 }
3334
3335 EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
3336 EXPECT_EQ(md.filter_off, 0);
3337
3338 md.filter_off = 1;
3339 ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
3340 EXPECT_EQ(sizeof(md), ret);
3341 EXPECT_EQ(md.flags, 0);
3342 EXPECT_EQ(md.filter_off, 1);
3343
3344 skip:
3345 ASSERT_EQ(0, kill(pid, SIGKILL));
3346 }
3347
user_notif_syscall(int nr,unsigned int flags)3348 static int user_notif_syscall(int nr, unsigned int flags)
3349 {
3350 struct sock_filter filter[] = {
3351 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
3352 offsetof(struct seccomp_data, nr)),
3353 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, nr, 0, 1),
3354 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_USER_NOTIF),
3355 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3356 };
3357
3358 struct sock_fprog prog = {
3359 .len = (unsigned short)ARRAY_SIZE(filter),
3360 .filter = filter,
3361 };
3362
3363 return seccomp(SECCOMP_SET_MODE_FILTER, flags, &prog);
3364 }
3365
3366 #define USER_NOTIF_MAGIC INT_MAX
TEST(user_notification_basic)3367 TEST(user_notification_basic)
3368 {
3369 pid_t pid;
3370 long ret;
3371 int status, listener;
3372 struct seccomp_notif req = {};
3373 struct seccomp_notif_resp resp = {};
3374 struct pollfd pollfd;
3375
3376 struct sock_filter filter[] = {
3377 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
3378 };
3379 struct sock_fprog prog = {
3380 .len = (unsigned short)ARRAY_SIZE(filter),
3381 .filter = filter,
3382 };
3383
3384 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3385 ASSERT_EQ(0, ret) {
3386 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3387 }
3388
3389 pid = fork();
3390 ASSERT_GE(pid, 0);
3391
3392 /* Check that we get -ENOSYS with no listener attached */
3393 if (pid == 0) {
3394 if (user_notif_syscall(__NR_getppid, 0) < 0)
3395 exit(1);
3396 ret = syscall(__NR_getppid);
3397 exit(ret >= 0 || errno != ENOSYS);
3398 }
3399
3400 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3401 EXPECT_EQ(true, WIFEXITED(status));
3402 EXPECT_EQ(0, WEXITSTATUS(status));
3403
3404 /* Add some no-op filters for grins. */
3405 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3406 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3407 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3408 EXPECT_EQ(seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog), 0);
3409
3410 /* Check that the basic notification machinery works */
3411 listener = user_notif_syscall(__NR_getppid,
3412 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3413 ASSERT_GE(listener, 0);
3414
3415 /* Installing a second listener in the chain should EBUSY */
3416 EXPECT_EQ(user_notif_syscall(__NR_getppid,
3417 SECCOMP_FILTER_FLAG_NEW_LISTENER),
3418 -1);
3419 EXPECT_EQ(errno, EBUSY);
3420
3421 pid = fork();
3422 ASSERT_GE(pid, 0);
3423
3424 if (pid == 0) {
3425 ret = syscall(__NR_getppid);
3426 exit(ret != USER_NOTIF_MAGIC);
3427 }
3428
3429 pollfd.fd = listener;
3430 pollfd.events = POLLIN | POLLOUT;
3431
3432 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3433 EXPECT_EQ(pollfd.revents, POLLIN);
3434
3435 /* Test that we can't pass garbage to the kernel. */
3436 memset(&req, 0, sizeof(req));
3437 req.pid = -1;
3438 errno = 0;
3439 ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req);
3440 EXPECT_EQ(-1, ret);
3441 EXPECT_EQ(EINVAL, errno);
3442
3443 if (ret) {
3444 req.pid = 0;
3445 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3446 }
3447
3448 pollfd.fd = listener;
3449 pollfd.events = POLLIN | POLLOUT;
3450
3451 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3452 EXPECT_EQ(pollfd.revents, POLLOUT);
3453
3454 EXPECT_EQ(req.data.nr, __NR_getppid);
3455
3456 resp.id = req.id;
3457 resp.error = 0;
3458 resp.val = USER_NOTIF_MAGIC;
3459
3460 /* check that we make sure flags == 0 */
3461 resp.flags = 1;
3462 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3463 EXPECT_EQ(errno, EINVAL);
3464
3465 resp.flags = 0;
3466 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3467
3468 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3469 EXPECT_EQ(true, WIFEXITED(status));
3470 EXPECT_EQ(0, WEXITSTATUS(status));
3471 }
3472
TEST(user_notification_with_tsync)3473 TEST(user_notification_with_tsync)
3474 {
3475 int ret;
3476 unsigned int flags;
3477
3478 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3479 ASSERT_EQ(0, ret) {
3480 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3481 }
3482
3483 /* these were exclusive */
3484 flags = SECCOMP_FILTER_FLAG_NEW_LISTENER |
3485 SECCOMP_FILTER_FLAG_TSYNC;
3486 ASSERT_EQ(-1, user_notif_syscall(__NR_getppid, flags));
3487 ASSERT_EQ(EINVAL, errno);
3488
3489 /* but now they're not */
3490 flags |= SECCOMP_FILTER_FLAG_TSYNC_ESRCH;
3491 ret = user_notif_syscall(__NR_getppid, flags);
3492 close(ret);
3493 ASSERT_LE(0, ret);
3494 }
3495
TEST(user_notification_kill_in_middle)3496 TEST(user_notification_kill_in_middle)
3497 {
3498 pid_t pid;
3499 long ret;
3500 int listener;
3501 struct seccomp_notif req = {};
3502 struct seccomp_notif_resp resp = {};
3503
3504 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3505 ASSERT_EQ(0, ret) {
3506 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3507 }
3508
3509 listener = user_notif_syscall(__NR_getppid,
3510 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3511 ASSERT_GE(listener, 0);
3512
3513 /*
3514 * Check that nothing bad happens when we kill the task in the middle
3515 * of a syscall.
3516 */
3517 pid = fork();
3518 ASSERT_GE(pid, 0);
3519
3520 if (pid == 0) {
3521 ret = syscall(__NR_getppid);
3522 exit(ret != USER_NOTIF_MAGIC);
3523 }
3524
3525 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3526 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), 0);
3527
3528 EXPECT_EQ(kill(pid, SIGKILL), 0);
3529 EXPECT_EQ(waitpid(pid, NULL, 0), pid);
3530
3531 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ID_VALID, &req.id), -1);
3532
3533 resp.id = req.id;
3534 ret = ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp);
3535 EXPECT_EQ(ret, -1);
3536 EXPECT_EQ(errno, ENOENT);
3537 }
3538
3539 static int handled = -1;
3540
signal_handler(int signal)3541 static void signal_handler(int signal)
3542 {
3543 if (write(handled, "c", 1) != 1)
3544 perror("write from signal");
3545 }
3546
TEST(user_notification_signal)3547 TEST(user_notification_signal)
3548 {
3549 pid_t pid;
3550 long ret;
3551 int status, listener, sk_pair[2];
3552 struct seccomp_notif req = {};
3553 struct seccomp_notif_resp resp = {};
3554 char c;
3555
3556 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3557 ASSERT_EQ(0, ret) {
3558 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3559 }
3560
3561 ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);
3562
3563 listener = user_notif_syscall(__NR_gettid,
3564 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3565 ASSERT_GE(listener, 0);
3566
3567 pid = fork();
3568 ASSERT_GE(pid, 0);
3569
3570 if (pid == 0) {
3571 close(sk_pair[0]);
3572 handled = sk_pair[1];
3573 if (signal(SIGUSR1, signal_handler) == SIG_ERR) {
3574 perror("signal");
3575 exit(1);
3576 }
3577 /*
3578 * ERESTARTSYS behavior is a bit hard to test, because we need
3579 * to rely on a signal that has not yet been handled. Let's at
3580 * least check that the error code gets propagated through, and
3581 * hope that it doesn't break when there is actually a signal :)
3582 */
3583 ret = syscall(__NR_gettid);
3584 exit(!(ret == -1 && errno == 512));
3585 }
3586
3587 close(sk_pair[1]);
3588
3589 memset(&req, 0, sizeof(req));
3590 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3591
3592 EXPECT_EQ(kill(pid, SIGUSR1), 0);
3593
3594 /*
3595 * Make sure the signal really is delivered, which means we're not
3596 * stuck in the user notification code any more and the notification
3597 * should be dead.
3598 */
3599 EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
3600
3601 resp.id = req.id;
3602 resp.error = -EPERM;
3603 resp.val = 0;
3604
3605 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3606 EXPECT_EQ(errno, ENOENT);
3607
3608 memset(&req, 0, sizeof(req));
3609 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3610
3611 resp.id = req.id;
3612 resp.error = -512; /* -ERESTARTSYS */
3613 resp.val = 0;
3614
3615 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3616
3617 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3618 EXPECT_EQ(true, WIFEXITED(status));
3619 EXPECT_EQ(0, WEXITSTATUS(status));
3620 }
3621
TEST(user_notification_closed_listener)3622 TEST(user_notification_closed_listener)
3623 {
3624 pid_t pid;
3625 long ret;
3626 int status, listener;
3627
3628 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3629 ASSERT_EQ(0, ret) {
3630 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3631 }
3632
3633 listener = user_notif_syscall(__NR_getppid,
3634 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3635 ASSERT_GE(listener, 0);
3636
3637 /*
3638 * Check that we get an ENOSYS when the listener is closed.
3639 */
3640 pid = fork();
3641 ASSERT_GE(pid, 0);
3642 if (pid == 0) {
3643 close(listener);
3644 ret = syscall(__NR_getppid);
3645 exit(ret != -1 && errno != ENOSYS);
3646 }
3647
3648 close(listener);
3649
3650 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3651 EXPECT_EQ(true, WIFEXITED(status));
3652 EXPECT_EQ(0, WEXITSTATUS(status));
3653 }
3654
3655 /*
3656 * Check that a pid in a child namespace still shows up as valid in ours.
3657 */
TEST(user_notification_child_pid_ns)3658 TEST(user_notification_child_pid_ns)
3659 {
3660 pid_t pid;
3661 int status, listener;
3662 struct seccomp_notif req = {};
3663 struct seccomp_notif_resp resp = {};
3664
3665 ASSERT_EQ(unshare(CLONE_NEWUSER | CLONE_NEWPID), 0) {
3666 if (errno == EINVAL)
3667 SKIP(return, "kernel missing CLONE_NEWUSER support");
3668 };
3669
3670 listener = user_notif_syscall(__NR_getppid,
3671 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3672 ASSERT_GE(listener, 0);
3673
3674 pid = fork();
3675 ASSERT_GE(pid, 0);
3676
3677 if (pid == 0)
3678 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3679
3680 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3681 EXPECT_EQ(req.pid, pid);
3682
3683 resp.id = req.id;
3684 resp.error = 0;
3685 resp.val = USER_NOTIF_MAGIC;
3686
3687 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3688
3689 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3690 EXPECT_EQ(true, WIFEXITED(status));
3691 EXPECT_EQ(0, WEXITSTATUS(status));
3692 close(listener);
3693 }
3694
3695 /*
3696 * Check that a pid in a sibling (i.e. unrelated) namespace shows up as 0, i.e.
3697 * invalid.
3698 */
TEST(user_notification_sibling_pid_ns)3699 TEST(user_notification_sibling_pid_ns)
3700 {
3701 pid_t pid, pid2;
3702 int status, listener;
3703 struct seccomp_notif req = {};
3704 struct seccomp_notif_resp resp = {};
3705
3706 ASSERT_EQ(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0), 0) {
3707 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3708 }
3709
3710 listener = user_notif_syscall(__NR_getppid,
3711 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3712 ASSERT_GE(listener, 0);
3713
3714 pid = fork();
3715 ASSERT_GE(pid, 0);
3716
3717 if (pid == 0) {
3718 ASSERT_EQ(unshare(CLONE_NEWPID), 0) {
3719 if (errno == EPERM)
3720 SKIP(return, "CLONE_NEWPID requires CAP_SYS_ADMIN");
3721 else if (errno == EINVAL)
3722 SKIP(return, "CLONE_NEWPID is invalid (missing CONFIG_PID_NS?)");
3723 }
3724
3725 pid2 = fork();
3726 ASSERT_GE(pid2, 0);
3727
3728 if (pid2 == 0)
3729 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3730
3731 EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
3732 EXPECT_EQ(true, WIFEXITED(status));
3733 EXPECT_EQ(0, WEXITSTATUS(status));
3734 exit(WEXITSTATUS(status));
3735 }
3736
3737 /* Create the sibling ns, and sibling in it. */
3738 ASSERT_EQ(unshare(CLONE_NEWPID), 0) {
3739 if (errno == EPERM)
3740 SKIP(return, "CLONE_NEWPID requires CAP_SYS_ADMIN");
3741 else if (errno == EINVAL)
3742 SKIP(return, "CLONE_NEWPID is invalid (missing CONFIG_PID_NS?)");
3743 }
3744 ASSERT_EQ(errno, 0);
3745
3746 pid2 = fork();
3747 ASSERT_GE(pid2, 0);
3748
3749 if (pid2 == 0) {
3750 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3751 /*
3752 * The pid should be 0, i.e. the task is in some namespace that
3753 * we can't "see".
3754 */
3755 EXPECT_EQ(req.pid, 0);
3756
3757 resp.id = req.id;
3758 resp.error = 0;
3759 resp.val = USER_NOTIF_MAGIC;
3760
3761 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3762 exit(0);
3763 }
3764
3765 close(listener);
3766
3767 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3768 EXPECT_EQ(true, WIFEXITED(status));
3769 EXPECT_EQ(0, WEXITSTATUS(status));
3770
3771 EXPECT_EQ(waitpid(pid2, &status, 0), pid2);
3772 EXPECT_EQ(true, WIFEXITED(status));
3773 EXPECT_EQ(0, WEXITSTATUS(status));
3774 }
3775
TEST(user_notification_fault_recv)3776 TEST(user_notification_fault_recv)
3777 {
3778 pid_t pid;
3779 int status, listener;
3780 struct seccomp_notif req = {};
3781 struct seccomp_notif_resp resp = {};
3782
3783 ASSERT_EQ(unshare(CLONE_NEWUSER), 0) {
3784 if (errno == EINVAL)
3785 SKIP(return, "kernel missing CLONE_NEWUSER support");
3786 }
3787
3788 listener = user_notif_syscall(__NR_getppid,
3789 SECCOMP_FILTER_FLAG_NEW_LISTENER);
3790 ASSERT_GE(listener, 0);
3791
3792 pid = fork();
3793 ASSERT_GE(pid, 0);
3794
3795 if (pid == 0)
3796 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
3797
3798 /* Do a bad recv() */
3799 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, NULL), -1);
3800 EXPECT_EQ(errno, EFAULT);
3801
3802 /* We should still be able to receive this notification, though. */
3803 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3804 EXPECT_EQ(req.pid, pid);
3805
3806 resp.id = req.id;
3807 resp.error = 0;
3808 resp.val = USER_NOTIF_MAGIC;
3809
3810 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
3811
3812 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3813 EXPECT_EQ(true, WIFEXITED(status));
3814 EXPECT_EQ(0, WEXITSTATUS(status));
3815 }
3816
TEST(seccomp_get_notif_sizes)3817 TEST(seccomp_get_notif_sizes)
3818 {
3819 struct seccomp_notif_sizes sizes;
3820
3821 ASSERT_EQ(seccomp(SECCOMP_GET_NOTIF_SIZES, 0, &sizes), 0);
3822 EXPECT_EQ(sizes.seccomp_notif, sizeof(struct seccomp_notif));
3823 EXPECT_EQ(sizes.seccomp_notif_resp, sizeof(struct seccomp_notif_resp));
3824 }
3825
TEST(user_notification_continue)3826 TEST(user_notification_continue)
3827 {
3828 pid_t pid;
3829 long ret;
3830 int status, listener;
3831 struct seccomp_notif req = {};
3832 struct seccomp_notif_resp resp = {};
3833 struct pollfd pollfd;
3834
3835 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3836 ASSERT_EQ(0, ret) {
3837 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3838 }
3839
3840 listener = user_notif_syscall(__NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER);
3841 ASSERT_GE(listener, 0);
3842
3843 pid = fork();
3844 ASSERT_GE(pid, 0);
3845
3846 if (pid == 0) {
3847 int dup_fd, pipe_fds[2];
3848 pid_t self;
3849
3850 ASSERT_GE(pipe(pipe_fds), 0);
3851
3852 dup_fd = dup(pipe_fds[0]);
3853 ASSERT_GE(dup_fd, 0);
3854 EXPECT_NE(pipe_fds[0], dup_fd);
3855
3856 self = getpid();
3857 ASSERT_EQ(filecmp(self, self, pipe_fds[0], dup_fd), 0);
3858 exit(0);
3859 }
3860
3861 pollfd.fd = listener;
3862 pollfd.events = POLLIN | POLLOUT;
3863
3864 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3865 EXPECT_EQ(pollfd.revents, POLLIN);
3866
3867 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
3868
3869 pollfd.fd = listener;
3870 pollfd.events = POLLIN | POLLOUT;
3871
3872 EXPECT_GT(poll(&pollfd, 1, -1), 0);
3873 EXPECT_EQ(pollfd.revents, POLLOUT);
3874
3875 EXPECT_EQ(req.data.nr, __NR_dup);
3876
3877 resp.id = req.id;
3878 resp.flags = SECCOMP_USER_NOTIF_FLAG_CONTINUE;
3879
3880 /*
3881 * Verify that setting SECCOMP_USER_NOTIF_FLAG_CONTINUE enforces other
3882 * args be set to 0.
3883 */
3884 resp.error = 0;
3885 resp.val = USER_NOTIF_MAGIC;
3886 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3887 EXPECT_EQ(errno, EINVAL);
3888
3889 resp.error = USER_NOTIF_MAGIC;
3890 resp.val = 0;
3891 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), -1);
3892 EXPECT_EQ(errno, EINVAL);
3893
3894 resp.error = 0;
3895 resp.val = 0;
3896 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0) {
3897 if (errno == EINVAL)
3898 SKIP(goto skip, "Kernel does not support SECCOMP_USER_NOTIF_FLAG_CONTINUE");
3899 }
3900
3901 skip:
3902 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3903 EXPECT_EQ(true, WIFEXITED(status));
3904 EXPECT_EQ(0, WEXITSTATUS(status)) {
3905 if (WEXITSTATUS(status) == 2) {
3906 SKIP(return, "Kernel does not support kcmp() syscall");
3907 return;
3908 }
3909 }
3910 }
3911
TEST(user_notification_filter_empty)3912 TEST(user_notification_filter_empty)
3913 {
3914 pid_t pid;
3915 long ret;
3916 int status;
3917 struct pollfd pollfd;
3918 struct __clone_args args = {
3919 .flags = CLONE_FILES,
3920 .exit_signal = SIGCHLD,
3921 };
3922
3923 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3924 ASSERT_EQ(0, ret) {
3925 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3926 }
3927
3928 if (__NR_clone3 < 0)
3929 SKIP(return, "Test not built with clone3 support");
3930
3931 pid = sys_clone3(&args, sizeof(args));
3932 ASSERT_GE(pid, 0);
3933
3934 if (pid == 0) {
3935 int listener;
3936
3937 listener = user_notif_syscall(__NR_mknodat, SECCOMP_FILTER_FLAG_NEW_LISTENER);
3938 if (listener < 0)
3939 _exit(EXIT_FAILURE);
3940
3941 if (dup2(listener, 200) != 200)
3942 _exit(EXIT_FAILURE);
3943
3944 close(listener);
3945
3946 _exit(EXIT_SUCCESS);
3947 }
3948
3949 EXPECT_EQ(waitpid(pid, &status, 0), pid);
3950 EXPECT_EQ(true, WIFEXITED(status));
3951 EXPECT_EQ(0, WEXITSTATUS(status));
3952
3953 /*
3954 * The seccomp filter has become unused so we should be notified once
3955 * the kernel gets around to cleaning up task struct.
3956 */
3957 pollfd.fd = 200;
3958 pollfd.events = POLLHUP;
3959
3960 EXPECT_GT(poll(&pollfd, 1, 2000), 0);
3961 EXPECT_GT((pollfd.revents & POLLHUP) ?: 0, 0);
3962 }
3963
TEST(user_ioctl_notification_filter_empty)3964 TEST(user_ioctl_notification_filter_empty)
3965 {
3966 pid_t pid;
3967 long ret;
3968 int status, p[2];
3969 struct __clone_args args = {
3970 .flags = CLONE_FILES,
3971 .exit_signal = SIGCHLD,
3972 };
3973 struct seccomp_notif req = {};
3974
3975 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
3976 ASSERT_EQ(0, ret) {
3977 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
3978 }
3979
3980 if (__NR_clone3 < 0)
3981 SKIP(return, "Test not built with clone3 support");
3982
3983 ASSERT_EQ(0, pipe(p));
3984
3985 pid = sys_clone3(&args, sizeof(args));
3986 ASSERT_GE(pid, 0);
3987
3988 if (pid == 0) {
3989 int listener;
3990
3991 listener = user_notif_syscall(__NR_mknodat, SECCOMP_FILTER_FLAG_NEW_LISTENER);
3992 if (listener < 0)
3993 _exit(EXIT_FAILURE);
3994
3995 if (dup2(listener, 200) != 200)
3996 _exit(EXIT_FAILURE);
3997 close(p[1]);
3998 close(listener);
3999 sleep(1);
4000
4001 _exit(EXIT_SUCCESS);
4002 }
4003 if (read(p[0], &status, 1) != 0)
4004 _exit(EXIT_SUCCESS);
4005 close(p[0]);
4006 /*
4007 * The seccomp filter has become unused so we should be notified once
4008 * the kernel gets around to cleaning up task struct.
4009 */
4010 EXPECT_EQ(ioctl(200, SECCOMP_IOCTL_NOTIF_RECV, &req), -1);
4011 EXPECT_EQ(errno, ENOENT);
4012
4013 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4014 EXPECT_EQ(true, WIFEXITED(status));
4015 EXPECT_EQ(0, WEXITSTATUS(status));
4016 }
4017
do_thread(void * data)4018 static void *do_thread(void *data)
4019 {
4020 return NULL;
4021 }
4022
TEST(user_notification_filter_empty_threaded)4023 TEST(user_notification_filter_empty_threaded)
4024 {
4025 pid_t pid;
4026 long ret;
4027 int status;
4028 struct pollfd pollfd;
4029 struct __clone_args args = {
4030 .flags = CLONE_FILES,
4031 .exit_signal = SIGCHLD,
4032 };
4033
4034 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4035 ASSERT_EQ(0, ret) {
4036 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4037 }
4038
4039 if (__NR_clone3 < 0)
4040 SKIP(return, "Test not built with clone3 support");
4041
4042 pid = sys_clone3(&args, sizeof(args));
4043 ASSERT_GE(pid, 0);
4044
4045 if (pid == 0) {
4046 pid_t pid1, pid2;
4047 int listener, status;
4048 pthread_t thread;
4049
4050 listener = user_notif_syscall(__NR_dup, SECCOMP_FILTER_FLAG_NEW_LISTENER);
4051 if (listener < 0)
4052 _exit(EXIT_FAILURE);
4053
4054 if (dup2(listener, 200) != 200)
4055 _exit(EXIT_FAILURE);
4056
4057 close(listener);
4058
4059 pid1 = fork();
4060 if (pid1 < 0)
4061 _exit(EXIT_FAILURE);
4062
4063 if (pid1 == 0)
4064 _exit(EXIT_SUCCESS);
4065
4066 pid2 = fork();
4067 if (pid2 < 0)
4068 _exit(EXIT_FAILURE);
4069
4070 if (pid2 == 0)
4071 _exit(EXIT_SUCCESS);
4072
4073 if (pthread_create(&thread, NULL, do_thread, NULL) ||
4074 pthread_join(thread, NULL))
4075 _exit(EXIT_FAILURE);
4076
4077 if (pthread_create(&thread, NULL, do_thread, NULL) ||
4078 pthread_join(thread, NULL))
4079 _exit(EXIT_FAILURE);
4080
4081 if (waitpid(pid1, &status, 0) != pid1 || !WIFEXITED(status) ||
4082 WEXITSTATUS(status))
4083 _exit(EXIT_FAILURE);
4084
4085 if (waitpid(pid2, &status, 0) != pid2 || !WIFEXITED(status) ||
4086 WEXITSTATUS(status))
4087 _exit(EXIT_FAILURE);
4088
4089 exit(EXIT_SUCCESS);
4090 }
4091
4092 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4093 EXPECT_EQ(true, WIFEXITED(status));
4094 EXPECT_EQ(0, WEXITSTATUS(status));
4095
4096 /*
4097 * The seccomp filter has become unused so we should be notified once
4098 * the kernel gets around to cleaning up task struct.
4099 */
4100 pollfd.fd = 200;
4101 pollfd.events = POLLHUP;
4102
4103 EXPECT_GT(poll(&pollfd, 1, 2000), 0);
4104 EXPECT_GT((pollfd.revents & POLLHUP) ?: 0, 0);
4105 }
4106
4107
get_next_fd(int prev_fd)4108 int get_next_fd(int prev_fd)
4109 {
4110 for (int i = prev_fd + 1; i < FD_SETSIZE; ++i) {
4111 if (fcntl(i, F_GETFD) == -1)
4112 return i;
4113 }
4114 _exit(EXIT_FAILURE);
4115 }
4116
TEST(user_notification_addfd)4117 TEST(user_notification_addfd)
4118 {
4119 pid_t pid;
4120 long ret;
4121 int status, listener, memfd, fd, nextfd;
4122 struct seccomp_notif_addfd addfd = {};
4123 struct seccomp_notif_addfd_small small = {};
4124 struct seccomp_notif_addfd_big big = {};
4125 struct seccomp_notif req = {};
4126 struct seccomp_notif_resp resp = {};
4127 /* 100 ms */
4128 struct timespec delay = { .tv_nsec = 100000000 };
4129
4130 /* There may be arbitrary already-open fds at test start. */
4131 memfd = memfd_create("test", 0);
4132 ASSERT_GE(memfd, 0);
4133 nextfd = get_next_fd(memfd);
4134
4135 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4136 ASSERT_EQ(0, ret) {
4137 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4138 }
4139
4140 /* fd: 4 */
4141 /* Check that the basic notification machinery works */
4142 listener = user_notif_syscall(__NR_getppid,
4143 SECCOMP_FILTER_FLAG_NEW_LISTENER);
4144 ASSERT_EQ(listener, nextfd);
4145 nextfd = get_next_fd(nextfd);
4146
4147 pid = fork();
4148 ASSERT_GE(pid, 0);
4149
4150 if (pid == 0) {
4151 /* fds will be added and this value is expected */
4152 if (syscall(__NR_getppid) != USER_NOTIF_MAGIC)
4153 exit(1);
4154
4155 /* Atomic addfd+send is received here. Check it is a valid fd */
4156 if (fcntl(syscall(__NR_getppid), F_GETFD) == -1)
4157 exit(1);
4158
4159 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
4160 }
4161
4162 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4163
4164 addfd.srcfd = memfd;
4165 addfd.newfd = 0;
4166 addfd.id = req.id;
4167 addfd.flags = 0x0;
4168
4169 /* Verify bad newfd_flags cannot be set */
4170 addfd.newfd_flags = ~O_CLOEXEC;
4171 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4172 EXPECT_EQ(errno, EINVAL);
4173 addfd.newfd_flags = O_CLOEXEC;
4174
4175 /* Verify bad flags cannot be set */
4176 addfd.flags = 0xff;
4177 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4178 EXPECT_EQ(errno, EINVAL);
4179 addfd.flags = 0;
4180
4181 /* Verify that remote_fd cannot be set without setting flags */
4182 addfd.newfd = 1;
4183 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4184 EXPECT_EQ(errno, EINVAL);
4185 addfd.newfd = 0;
4186
4187 /* Verify small size cannot be set */
4188 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_SMALL, &small), -1);
4189 EXPECT_EQ(errno, EINVAL);
4190
4191 /* Verify we can't send bits filled in unknown buffer area */
4192 memset(&big, 0xAA, sizeof(big));
4193 big.addfd = addfd;
4194 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_BIG, &big), -1);
4195 EXPECT_EQ(errno, E2BIG);
4196
4197
4198 /* Verify we can set an arbitrary remote fd */
4199 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
4200 EXPECT_EQ(fd, nextfd);
4201 nextfd = get_next_fd(nextfd);
4202 EXPECT_EQ(filecmp(getpid(), pid, memfd, fd), 0);
4203
4204 /* Verify we can set an arbitrary remote fd with large size */
4205 memset(&big, 0x0, sizeof(big));
4206 big.addfd = addfd;
4207 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD_BIG, &big);
4208 EXPECT_EQ(fd, nextfd);
4209 nextfd = get_next_fd(nextfd);
4210
4211 /* Verify we can set a specific remote fd */
4212 addfd.newfd = 42;
4213 addfd.flags = SECCOMP_ADDFD_FLAG_SETFD;
4214 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
4215 EXPECT_EQ(fd, 42);
4216 EXPECT_EQ(filecmp(getpid(), pid, memfd, fd), 0);
4217
4218 /* Resume syscall */
4219 resp.id = req.id;
4220 resp.error = 0;
4221 resp.val = USER_NOTIF_MAGIC;
4222 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4223
4224 /*
4225 * This sets the ID of the ADD FD to the last request plus 1. The
4226 * notification ID increments 1 per notification.
4227 */
4228 addfd.id = req.id + 1;
4229
4230 /* This spins until the underlying notification is generated */
4231 while (ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd) != -1 &&
4232 errno != -EINPROGRESS)
4233 nanosleep(&delay, NULL);
4234
4235 memset(&req, 0, sizeof(req));
4236 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4237 ASSERT_EQ(addfd.id, req.id);
4238
4239 /* Verify we can do an atomic addfd and send */
4240 addfd.newfd = 0;
4241 addfd.flags = SECCOMP_ADDFD_FLAG_SEND;
4242 fd = ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd);
4243 /*
4244 * Child has earlier "low" fds and now 42, so we expect the next
4245 * lowest available fd to be assigned here.
4246 */
4247 EXPECT_EQ(fd, nextfd);
4248 nextfd = get_next_fd(nextfd);
4249 ASSERT_EQ(filecmp(getpid(), pid, memfd, fd), 0);
4250
4251 /*
4252 * This sets the ID of the ADD FD to the last request plus 1. The
4253 * notification ID increments 1 per notification.
4254 */
4255 addfd.id = req.id + 1;
4256
4257 /* This spins until the underlying notification is generated */
4258 while (ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd) != -1 &&
4259 errno != -EINPROGRESS)
4260 nanosleep(&delay, NULL);
4261
4262 memset(&req, 0, sizeof(req));
4263 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4264 ASSERT_EQ(addfd.id, req.id);
4265
4266 resp.id = req.id;
4267 resp.error = 0;
4268 resp.val = USER_NOTIF_MAGIC;
4269 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4270
4271 /* Wait for child to finish. */
4272 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4273 EXPECT_EQ(true, WIFEXITED(status));
4274 EXPECT_EQ(0, WEXITSTATUS(status));
4275
4276 close(memfd);
4277 }
4278
TEST(user_notification_addfd_rlimit)4279 TEST(user_notification_addfd_rlimit)
4280 {
4281 pid_t pid;
4282 long ret;
4283 int status, listener, memfd;
4284 struct seccomp_notif_addfd addfd = {};
4285 struct seccomp_notif req = {};
4286 struct seccomp_notif_resp resp = {};
4287 const struct rlimit lim = {
4288 .rlim_cur = 0,
4289 .rlim_max = 0,
4290 };
4291
4292 memfd = memfd_create("test", 0);
4293 ASSERT_GE(memfd, 0);
4294
4295 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4296 ASSERT_EQ(0, ret) {
4297 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4298 }
4299
4300 /* Check that the basic notification machinery works */
4301 listener = user_notif_syscall(__NR_getppid,
4302 SECCOMP_FILTER_FLAG_NEW_LISTENER);
4303 ASSERT_GE(listener, 0);
4304
4305 pid = fork();
4306 ASSERT_GE(pid, 0);
4307
4308 if (pid == 0)
4309 exit(syscall(__NR_getppid) != USER_NOTIF_MAGIC);
4310
4311
4312 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4313
4314 ASSERT_EQ(prlimit(pid, RLIMIT_NOFILE, &lim, NULL), 0);
4315
4316 addfd.srcfd = memfd;
4317 addfd.newfd_flags = O_CLOEXEC;
4318 addfd.newfd = 0;
4319 addfd.id = req.id;
4320 addfd.flags = 0;
4321
4322 /* Should probably spot check /proc/sys/fs/file-nr */
4323 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4324 EXPECT_EQ(errno, EMFILE);
4325
4326 addfd.flags = SECCOMP_ADDFD_FLAG_SEND;
4327 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4328 EXPECT_EQ(errno, EMFILE);
4329
4330 addfd.newfd = 100;
4331 addfd.flags = SECCOMP_ADDFD_FLAG_SETFD;
4332 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_ADDFD, &addfd), -1);
4333 EXPECT_EQ(errno, EBADF);
4334
4335 resp.id = req.id;
4336 resp.error = 0;
4337 resp.val = USER_NOTIF_MAGIC;
4338
4339 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4340
4341 /* Wait for child to finish. */
4342 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4343 EXPECT_EQ(true, WIFEXITED(status));
4344 EXPECT_EQ(0, WEXITSTATUS(status));
4345
4346 close(memfd);
4347 }
4348
4349 #ifndef SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP
4350 #define SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP (1UL << 0)
4351 #define SECCOMP_IOCTL_NOTIF_SET_FLAGS SECCOMP_IOW(4, __u64)
4352 #endif
4353
TEST(user_notification_sync)4354 TEST(user_notification_sync)
4355 {
4356 struct seccomp_notif req = {};
4357 struct seccomp_notif_resp resp = {};
4358 int status, listener;
4359 pid_t pid;
4360 long ret;
4361
4362 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4363 ASSERT_EQ(0, ret) {
4364 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4365 }
4366
4367 listener = user_notif_syscall(__NR_getppid,
4368 SECCOMP_FILTER_FLAG_NEW_LISTENER);
4369 ASSERT_GE(listener, 0);
4370
4371 /* Try to set invalid flags. */
4372 EXPECT_SYSCALL_RETURN(-EINVAL,
4373 ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS, 0xffffffff, 0));
4374
4375 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SET_FLAGS,
4376 SECCOMP_USER_NOTIF_FD_SYNC_WAKE_UP, 0), 0);
4377
4378 pid = fork();
4379 ASSERT_GE(pid, 0);
4380 if (pid == 0) {
4381 ret = syscall(__NR_getppid);
4382 ASSERT_EQ(ret, USER_NOTIF_MAGIC) {
4383 _exit(1);
4384 }
4385 _exit(0);
4386 }
4387
4388 req.pid = 0;
4389 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4390
4391 ASSERT_EQ(req.data.nr, __NR_getppid);
4392
4393 resp.id = req.id;
4394 resp.error = 0;
4395 resp.val = USER_NOTIF_MAGIC;
4396 resp.flags = 0;
4397 ASSERT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4398
4399 ASSERT_EQ(waitpid(pid, &status, 0), pid);
4400 ASSERT_EQ(status, 0);
4401 }
4402
4403
4404 /* Make sure PTRACE_O_SUSPEND_SECCOMP requires CAP_SYS_ADMIN. */
FIXTURE(O_SUSPEND_SECCOMP)4405 FIXTURE(O_SUSPEND_SECCOMP) {
4406 pid_t pid;
4407 };
4408
FIXTURE_SETUP(O_SUSPEND_SECCOMP)4409 FIXTURE_SETUP(O_SUSPEND_SECCOMP)
4410 {
4411 ERRNO_FILTER(block_read, E2BIG);
4412 cap_value_t cap_list[] = { CAP_SYS_ADMIN };
4413 cap_t caps;
4414
4415 self->pid = 0;
4416
4417 /* make sure we don't have CAP_SYS_ADMIN */
4418 caps = cap_get_proc();
4419 ASSERT_NE(NULL, caps);
4420 ASSERT_EQ(0, cap_set_flag(caps, CAP_EFFECTIVE, 1, cap_list, CAP_CLEAR));
4421 ASSERT_EQ(0, cap_set_proc(caps));
4422 cap_free(caps);
4423
4424 ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0));
4425 ASSERT_EQ(0, prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_block_read));
4426
4427 self->pid = fork();
4428 ASSERT_GE(self->pid, 0);
4429
4430 if (self->pid == 0) {
4431 while (1)
4432 pause();
4433 _exit(127);
4434 }
4435 }
4436
FIXTURE_TEARDOWN(O_SUSPEND_SECCOMP)4437 FIXTURE_TEARDOWN(O_SUSPEND_SECCOMP)
4438 {
4439 if (self->pid)
4440 kill(self->pid, SIGKILL);
4441 }
4442
TEST_F(O_SUSPEND_SECCOMP,setoptions)4443 TEST_F(O_SUSPEND_SECCOMP, setoptions)
4444 {
4445 int wstatus;
4446
4447 ASSERT_EQ(0, ptrace(PTRACE_ATTACH, self->pid, NULL, 0));
4448 ASSERT_EQ(self->pid, wait(&wstatus));
4449 ASSERT_EQ(-1, ptrace(PTRACE_SETOPTIONS, self->pid, NULL, PTRACE_O_SUSPEND_SECCOMP));
4450 if (errno == EINVAL)
4451 SKIP(return, "Kernel does not support PTRACE_O_SUSPEND_SECCOMP (missing CONFIG_CHECKPOINT_RESTORE?)");
4452 ASSERT_EQ(EPERM, errno);
4453 }
4454
TEST_F(O_SUSPEND_SECCOMP,seize)4455 TEST_F(O_SUSPEND_SECCOMP, seize)
4456 {
4457 int ret;
4458
4459 ret = ptrace(PTRACE_SEIZE, self->pid, NULL, PTRACE_O_SUSPEND_SECCOMP);
4460 ASSERT_EQ(-1, ret);
4461 if (errno == EINVAL)
4462 SKIP(return, "Kernel does not support PTRACE_O_SUSPEND_SECCOMP (missing CONFIG_CHECKPOINT_RESTORE?)");
4463 ASSERT_EQ(EPERM, errno);
4464 }
4465
4466 /*
4467 * get_nth - Get the nth, space separated entry in a file.
4468 *
4469 * Returns the length of the read field.
4470 * Throws error if field is zero-lengthed.
4471 */
get_nth(struct __test_metadata * _metadata,const char * path,const unsigned int position,char ** entry)4472 static ssize_t get_nth(struct __test_metadata *_metadata, const char *path,
4473 const unsigned int position, char **entry)
4474 {
4475 char *line = NULL;
4476 unsigned int i;
4477 ssize_t nread;
4478 size_t len = 0;
4479 FILE *f;
4480
4481 f = fopen(path, "r");
4482 ASSERT_NE(f, NULL) {
4483 TH_LOG("Could not open %s: %s", path, strerror(errno));
4484 }
4485
4486 for (i = 0; i < position; i++) {
4487 nread = getdelim(&line, &len, ' ', f);
4488 ASSERT_GE(nread, 0) {
4489 TH_LOG("Failed to read %d entry in file %s", i, path);
4490 }
4491 }
4492 fclose(f);
4493
4494 ASSERT_GT(nread, 0) {
4495 TH_LOG("Entry in file %s had zero length", path);
4496 }
4497
4498 *entry = line;
4499 return nread - 1;
4500 }
4501
4502 /* For a given PID, get the task state (D, R, etc...) */
get_proc_stat(struct __test_metadata * _metadata,pid_t pid)4503 static char get_proc_stat(struct __test_metadata *_metadata, pid_t pid)
4504 {
4505 char proc_path[100] = {0};
4506 char status;
4507 char *line;
4508
4509 snprintf(proc_path, sizeof(proc_path), "/proc/%d/stat", pid);
4510 ASSERT_EQ(get_nth(_metadata, proc_path, 3, &line), 1);
4511
4512 status = *line;
4513 free(line);
4514
4515 return status;
4516 }
4517
TEST(user_notification_fifo)4518 TEST(user_notification_fifo)
4519 {
4520 struct seccomp_notif_resp resp = {};
4521 struct seccomp_notif req = {};
4522 int i, status, listener;
4523 pid_t pid, pids[3];
4524 __u64 baseid;
4525 long ret;
4526 /* 100 ms */
4527 struct timespec delay = { .tv_nsec = 100000000 };
4528
4529 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4530 ASSERT_EQ(0, ret) {
4531 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4532 }
4533
4534 /* Setup a listener */
4535 listener = user_notif_syscall(__NR_getppid,
4536 SECCOMP_FILTER_FLAG_NEW_LISTENER);
4537 ASSERT_GE(listener, 0);
4538
4539 pid = fork();
4540 ASSERT_GE(pid, 0);
4541
4542 if (pid == 0) {
4543 ret = syscall(__NR_getppid);
4544 exit(ret != USER_NOTIF_MAGIC);
4545 }
4546
4547 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4548 baseid = req.id + 1;
4549
4550 resp.id = req.id;
4551 resp.error = 0;
4552 resp.val = USER_NOTIF_MAGIC;
4553
4554 /* check that we make sure flags == 0 */
4555 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4556
4557 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4558 EXPECT_EQ(true, WIFEXITED(status));
4559 EXPECT_EQ(0, WEXITSTATUS(status));
4560
4561 /* Start children, and generate notifications */
4562 for (i = 0; i < ARRAY_SIZE(pids); i++) {
4563 pid = fork();
4564 if (pid == 0) {
4565 ret = syscall(__NR_getppid);
4566 exit(ret != USER_NOTIF_MAGIC);
4567 }
4568 pids[i] = pid;
4569 }
4570
4571 /* This spins until all of the children are sleeping */
4572 restart_wait:
4573 for (i = 0; i < ARRAY_SIZE(pids); i++) {
4574 if (get_proc_stat(_metadata, pids[i]) != 'S') {
4575 nanosleep(&delay, NULL);
4576 goto restart_wait;
4577 }
4578 }
4579
4580 /* Read the notifications in order (and respond) */
4581 for (i = 0; i < ARRAY_SIZE(pids); i++) {
4582 memset(&req, 0, sizeof(req));
4583 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4584 EXPECT_EQ(req.id, baseid + i);
4585 resp.id = req.id;
4586 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4587 }
4588
4589 /* Make sure notifications were received */
4590 for (i = 0; i < ARRAY_SIZE(pids); i++) {
4591 EXPECT_EQ(waitpid(pids[i], &status, 0), pids[i]);
4592 EXPECT_EQ(true, WIFEXITED(status));
4593 EXPECT_EQ(0, WEXITSTATUS(status));
4594 }
4595 }
4596
4597 /* get_proc_syscall - Get the syscall in progress for a given pid
4598 *
4599 * Returns the current syscall number for a given process
4600 * Returns -1 if not in syscall (running or blocked)
4601 */
get_proc_syscall(struct __test_metadata * _metadata,int pid)4602 static long get_proc_syscall(struct __test_metadata *_metadata, int pid)
4603 {
4604 char proc_path[100] = {0};
4605 long ret = -1;
4606 ssize_t nread;
4607 char *line;
4608
4609 snprintf(proc_path, sizeof(proc_path), "/proc/%d/syscall", pid);
4610 nread = get_nth(_metadata, proc_path, 1, &line);
4611 ASSERT_GT(nread, 0);
4612
4613 if (!strncmp("running", line, MIN(7, nread)))
4614 ret = strtol(line, NULL, 16);
4615
4616 free(line);
4617 return ret;
4618 }
4619
4620 /* Ensure non-fatal signals prior to receive are unmodified */
TEST(user_notification_wait_killable_pre_notification)4621 TEST(user_notification_wait_killable_pre_notification)
4622 {
4623 struct sigaction new_action = {
4624 .sa_handler = signal_handler,
4625 };
4626 int listener, status, sk_pair[2];
4627 pid_t pid;
4628 long ret;
4629 char c;
4630 /* 100 ms */
4631 struct timespec delay = { .tv_nsec = 100000000 };
4632
4633 ASSERT_EQ(sigemptyset(&new_action.sa_mask), 0);
4634
4635 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4636 ASSERT_EQ(0, ret)
4637 {
4638 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4639 }
4640
4641 ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);
4642
4643 listener = user_notif_syscall(
4644 __NR_getppid, SECCOMP_FILTER_FLAG_NEW_LISTENER |
4645 SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
4646 ASSERT_GE(listener, 0);
4647
4648 /*
4649 * Check that we can kill the process with SIGUSR1 prior to receiving
4650 * the notification. SIGUSR1 is wired up to a custom signal handler,
4651 * and make sure it gets called.
4652 */
4653 pid = fork();
4654 ASSERT_GE(pid, 0);
4655
4656 if (pid == 0) {
4657 close(sk_pair[0]);
4658 handled = sk_pair[1];
4659
4660 /* Setup the non-fatal sigaction without SA_RESTART */
4661 if (sigaction(SIGUSR1, &new_action, NULL)) {
4662 perror("sigaction");
4663 exit(1);
4664 }
4665
4666 ret = syscall(__NR_getppid);
4667 /* Make sure we got a return from a signal interruption */
4668 exit(ret != -1 || errno != EINTR);
4669 }
4670
4671 /*
4672 * Make sure we've gotten to the seccomp user notification wait
4673 * from getppid prior to sending any signals
4674 */
4675 while (get_proc_syscall(_metadata, pid) != __NR_getppid &&
4676 get_proc_stat(_metadata, pid) != 'S')
4677 nanosleep(&delay, NULL);
4678
4679 /* Send non-fatal kill signal */
4680 EXPECT_EQ(kill(pid, SIGUSR1), 0);
4681
4682 /* wait for process to exit (exit checks for EINTR) */
4683 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4684 EXPECT_EQ(true, WIFEXITED(status));
4685 EXPECT_EQ(0, WEXITSTATUS(status));
4686
4687 EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
4688 }
4689
4690 /* Ensure non-fatal signals after receive are blocked */
TEST(user_notification_wait_killable)4691 TEST(user_notification_wait_killable)
4692 {
4693 struct sigaction new_action = {
4694 .sa_handler = signal_handler,
4695 };
4696 struct seccomp_notif_resp resp = {};
4697 struct seccomp_notif req = {};
4698 int listener, status, sk_pair[2];
4699 pid_t pid;
4700 long ret;
4701 char c;
4702 /* 100 ms */
4703 struct timespec delay = { .tv_nsec = 100000000 };
4704
4705 ASSERT_EQ(sigemptyset(&new_action.sa_mask), 0);
4706
4707 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4708 ASSERT_EQ(0, ret)
4709 {
4710 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4711 }
4712
4713 ASSERT_EQ(socketpair(PF_LOCAL, SOCK_SEQPACKET, 0, sk_pair), 0);
4714
4715 listener = user_notif_syscall(
4716 __NR_getppid, SECCOMP_FILTER_FLAG_NEW_LISTENER |
4717 SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
4718 ASSERT_GE(listener, 0);
4719
4720 pid = fork();
4721 ASSERT_GE(pid, 0);
4722
4723 if (pid == 0) {
4724 close(sk_pair[0]);
4725 handled = sk_pair[1];
4726
4727 /* Setup the sigaction without SA_RESTART */
4728 if (sigaction(SIGUSR1, &new_action, NULL)) {
4729 perror("sigaction");
4730 exit(1);
4731 }
4732
4733 /* Make sure that the syscall is completed (no EINTR) */
4734 ret = syscall(__NR_getppid);
4735 exit(ret != USER_NOTIF_MAGIC);
4736 }
4737
4738 /*
4739 * Get the notification, to make move the notifying process into a
4740 * non-preemptible (TASK_KILLABLE) state.
4741 */
4742 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4743 /* Send non-fatal kill signal */
4744 EXPECT_EQ(kill(pid, SIGUSR1), 0);
4745
4746 /*
4747 * Make sure the task enters moves to TASK_KILLABLE by waiting for
4748 * D (Disk Sleep) state after receiving non-fatal signal.
4749 */
4750 while (get_proc_stat(_metadata, pid) != 'D')
4751 nanosleep(&delay, NULL);
4752
4753 resp.id = req.id;
4754 resp.val = USER_NOTIF_MAGIC;
4755 /* Make sure the notification is found and able to be replied to */
4756 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_SEND, &resp), 0);
4757
4758 /*
4759 * Make sure that the signal handler does get called once we're back in
4760 * userspace.
4761 */
4762 EXPECT_EQ(read(sk_pair[0], &c, 1), 1);
4763 /* wait for process to exit (exit checks for USER_NOTIF_MAGIC) */
4764 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4765 EXPECT_EQ(true, WIFEXITED(status));
4766 EXPECT_EQ(0, WEXITSTATUS(status));
4767 }
4768
4769 /* Ensure fatal signals after receive are not blocked */
TEST(user_notification_wait_killable_fatal)4770 TEST(user_notification_wait_killable_fatal)
4771 {
4772 struct seccomp_notif req = {};
4773 int listener, status;
4774 pid_t pid;
4775 long ret;
4776 /* 100 ms */
4777 struct timespec delay = { .tv_nsec = 100000000 };
4778
4779 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4780 ASSERT_EQ(0, ret)
4781 {
4782 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4783 }
4784
4785 listener = user_notif_syscall(
4786 __NR_getppid, SECCOMP_FILTER_FLAG_NEW_LISTENER |
4787 SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV);
4788 ASSERT_GE(listener, 0);
4789
4790 pid = fork();
4791 ASSERT_GE(pid, 0);
4792
4793 if (pid == 0) {
4794 /* This should never complete as it should get a SIGTERM */
4795 syscall(__NR_getppid);
4796 exit(1);
4797 }
4798
4799 while (get_proc_stat(_metadata, pid) != 'S')
4800 nanosleep(&delay, NULL);
4801
4802 /*
4803 * Get the notification, to make move the notifying process into a
4804 * non-preemptible (TASK_KILLABLE) state.
4805 */
4806 EXPECT_EQ(ioctl(listener, SECCOMP_IOCTL_NOTIF_RECV, &req), 0);
4807 /* Kill the process with a fatal signal */
4808 EXPECT_EQ(kill(pid, SIGTERM), 0);
4809
4810 /*
4811 * Wait for the process to exit, and make sure the process terminated
4812 * due to the SIGTERM signal.
4813 */
4814 EXPECT_EQ(waitpid(pid, &status, 0), pid);
4815 EXPECT_EQ(true, WIFSIGNALED(status));
4816 EXPECT_EQ(SIGTERM, WTERMSIG(status));
4817 }
4818
4819 struct tsync_vs_thread_leader_args {
4820 pthread_t leader;
4821 };
4822
tsync_vs_dead_thread_leader_sibling(void * _args)4823 static void *tsync_vs_dead_thread_leader_sibling(void *_args)
4824 {
4825 struct sock_filter allow_filter[] = {
4826 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
4827 };
4828 struct sock_fprog allow_prog = {
4829 .len = (unsigned short)ARRAY_SIZE(allow_filter),
4830 .filter = allow_filter,
4831 };
4832 struct tsync_vs_thread_leader_args *args = _args;
4833 void *retval;
4834 long ret;
4835
4836 ret = pthread_join(args->leader, &retval);
4837 if (ret)
4838 exit(1);
4839 if (retval != _args)
4840 exit(2);
4841 ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC, &allow_prog);
4842 if (ret)
4843 exit(3);
4844
4845 exit(0);
4846 }
4847
4848 /*
4849 * Ensure that a dead thread leader doesn't prevent installing new filters with
4850 * SECCOMP_FILTER_FLAG_TSYNC from other threads.
4851 */
TEST(tsync_vs_dead_thread_leader)4852 TEST(tsync_vs_dead_thread_leader)
4853 {
4854 int status;
4855 pid_t pid;
4856 long ret;
4857
4858 ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
4859 ASSERT_EQ(0, ret) {
4860 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
4861 }
4862
4863 pid = fork();
4864 ASSERT_GE(pid, 0);
4865
4866 if (pid == 0) {
4867 struct sock_filter allow_filter[] = {
4868 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
4869 };
4870 struct sock_fprog allow_prog = {
4871 .len = (unsigned short)ARRAY_SIZE(allow_filter),
4872 .filter = allow_filter,
4873 };
4874 struct tsync_vs_thread_leader_args *args;
4875 pthread_t sibling;
4876
4877 args = malloc(sizeof(*args));
4878 ASSERT_NE(NULL, args);
4879 args->leader = pthread_self();
4880
4881 ret = pthread_create(&sibling, NULL,
4882 tsync_vs_dead_thread_leader_sibling, args);
4883 ASSERT_EQ(0, ret);
4884
4885 /* Install a new filter just to the leader thread. */
4886 ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
4887 ASSERT_EQ(0, ret);
4888 pthread_exit(args);
4889 exit(1);
4890 }
4891
4892 EXPECT_EQ(pid, waitpid(pid, &status, 0));
4893 EXPECT_EQ(0, status);
4894 }
4895
probed(void)4896 noinline int probed(void)
4897 {
4898 return 1;
4899 }
4900
parse_uint_from_file(const char * file,const char * fmt)4901 static int parse_uint_from_file(const char *file, const char *fmt)
4902 {
4903 int err = -1, ret;
4904 FILE *f;
4905
4906 f = fopen(file, "re");
4907 if (f) {
4908 err = fscanf(f, fmt, &ret);
4909 fclose(f);
4910 }
4911 return err == 1 ? ret : err;
4912 }
4913
determine_uprobe_perf_type(void)4914 static int determine_uprobe_perf_type(void)
4915 {
4916 const char *file = "/sys/bus/event_source/devices/uprobe/type";
4917
4918 return parse_uint_from_file(file, "%d\n");
4919 }
4920
determine_uprobe_retprobe_bit(void)4921 static int determine_uprobe_retprobe_bit(void)
4922 {
4923 const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe";
4924
4925 return parse_uint_from_file(file, "config:%d\n");
4926 }
4927
get_uprobe_offset(const void * addr)4928 static ssize_t get_uprobe_offset(const void *addr)
4929 {
4930 size_t start, base, end;
4931 bool found = false;
4932 char buf[256];
4933 FILE *f;
4934
4935 f = fopen("/proc/self/maps", "r");
4936 if (!f)
4937 return -1;
4938
4939 while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) {
4940 if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) {
4941 found = true;
4942 break;
4943 }
4944 }
4945 fclose(f);
4946 return found ? (uintptr_t)addr - start + base : -1;
4947 }
4948
FIXTURE(URETPROBE)4949 FIXTURE(URETPROBE) {
4950 int fd;
4951 };
4952
FIXTURE_VARIANT(URETPROBE)4953 FIXTURE_VARIANT(URETPROBE) {
4954 /*
4955 * All of the URETPROBE behaviors can be tested with either
4956 * uretprobe attached or not
4957 */
4958 bool attach;
4959 };
4960
FIXTURE_VARIANT_ADD(URETPROBE,attached)4961 FIXTURE_VARIANT_ADD(URETPROBE, attached) {
4962 .attach = true,
4963 };
4964
FIXTURE_VARIANT_ADD(URETPROBE,not_attached)4965 FIXTURE_VARIANT_ADD(URETPROBE, not_attached) {
4966 .attach = false,
4967 };
4968
FIXTURE_SETUP(URETPROBE)4969 FIXTURE_SETUP(URETPROBE)
4970 {
4971 const size_t attr_sz = sizeof(struct perf_event_attr);
4972 struct perf_event_attr attr;
4973 ssize_t offset;
4974 int type, bit;
4975
4976 #ifndef __NR_uretprobe
4977 SKIP(return, "__NR_uretprobe syscall not defined");
4978 #endif
4979
4980 if (!variant->attach)
4981 return;
4982
4983 memset(&attr, 0, attr_sz);
4984
4985 type = determine_uprobe_perf_type();
4986 ASSERT_GE(type, 0);
4987 bit = determine_uprobe_retprobe_bit();
4988 ASSERT_GE(bit, 0);
4989 offset = get_uprobe_offset(probed);
4990 ASSERT_GE(offset, 0);
4991
4992 attr.config |= 1 << bit;
4993 attr.size = attr_sz;
4994 attr.type = type;
4995 attr.config1 = ptr_to_u64("/proc/self/exe");
4996 attr.config2 = offset;
4997
4998 self->fd = syscall(__NR_perf_event_open, &attr,
4999 getpid() /* pid */, -1 /* cpu */, -1 /* group_fd */,
5000 PERF_FLAG_FD_CLOEXEC);
5001 }
5002
FIXTURE_TEARDOWN(URETPROBE)5003 FIXTURE_TEARDOWN(URETPROBE)
5004 {
5005 /* we could call close(self->fd), but we'd need extra filter for
5006 * that and since we are calling _exit right away..
5007 */
5008 }
5009
run_probed_with_filter(struct sock_fprog * prog)5010 static int run_probed_with_filter(struct sock_fprog *prog)
5011 {
5012 if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) ||
5013 seccomp(SECCOMP_SET_MODE_FILTER, 0, prog)) {
5014 return -1;
5015 }
5016
5017 probed();
5018 return 0;
5019 }
5020
TEST_F(URETPROBE,uretprobe_default_allow)5021 TEST_F(URETPROBE, uretprobe_default_allow)
5022 {
5023 struct sock_filter filter[] = {
5024 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
5025 };
5026 struct sock_fprog prog = {
5027 .len = (unsigned short)ARRAY_SIZE(filter),
5028 .filter = filter,
5029 };
5030
5031 ASSERT_EQ(0, run_probed_with_filter(&prog));
5032 }
5033
TEST_F(URETPROBE,uretprobe_default_block)5034 TEST_F(URETPROBE, uretprobe_default_block)
5035 {
5036 struct sock_filter filter[] = {
5037 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
5038 offsetof(struct seccomp_data, nr)),
5039 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit_group, 1, 0),
5040 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
5041 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
5042 };
5043 struct sock_fprog prog = {
5044 .len = (unsigned short)ARRAY_SIZE(filter),
5045 .filter = filter,
5046 };
5047
5048 ASSERT_EQ(0, run_probed_with_filter(&prog));
5049 }
5050
TEST_F(URETPROBE,uretprobe_block_uretprobe_syscall)5051 TEST_F(URETPROBE, uretprobe_block_uretprobe_syscall)
5052 {
5053 struct sock_filter filter[] = {
5054 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
5055 offsetof(struct seccomp_data, nr)),
5056 #ifdef __NR_uretprobe
5057 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_uretprobe, 0, 1),
5058 #endif
5059 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
5060 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
5061 };
5062 struct sock_fprog prog = {
5063 .len = (unsigned short)ARRAY_SIZE(filter),
5064 .filter = filter,
5065 };
5066
5067 ASSERT_EQ(0, run_probed_with_filter(&prog));
5068 }
5069
TEST_F(URETPROBE,uretprobe_default_block_with_uretprobe_syscall)5070 TEST_F(URETPROBE, uretprobe_default_block_with_uretprobe_syscall)
5071 {
5072 struct sock_filter filter[] = {
5073 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
5074 offsetof(struct seccomp_data, nr)),
5075 #ifdef __NR_uretprobe
5076 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_uretprobe, 2, 0),
5077 #endif
5078 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit_group, 1, 0),
5079 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
5080 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
5081 };
5082 struct sock_fprog prog = {
5083 .len = (unsigned short)ARRAY_SIZE(filter),
5084 .filter = filter,
5085 };
5086
5087 ASSERT_EQ(0, run_probed_with_filter(&prog));
5088 }
5089
5090 /*
5091 * TODO:
5092 * - expand NNP testing
5093 * - better arch-specific TRACE and TRAP handlers.
5094 * - endianness checking when appropriate
5095 * - 64-bit arg prodding
5096 * - arch value testing (x86 modes especially)
5097 * - verify that FILTER_FLAG_LOG filters generate log messages
5098 * - verify that RET_LOG generates log messages
5099 */
5100
5101 TEST_HARNESS_MAIN
5102