tools/testing/selftests/seccomp/seccomp_bpf.c

   1 /*
   2  * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
   3  * Use of this source code is governed by the GPLv2 license.
   4  *
   5  * Test code for seccomp bpf.
   6  */
   7
   8 #include <sys/types.h>
   9
  10 /*
  11  * glibc 2.26 and later have SIGSYS in siginfo_t. Before that,
  12  * we need to use the kernel's siginfo.h file and trick glibc
  13  * into accepting it.
  14  */
  15 #if !__GLIBC_PREREQ(2, 26)
  16 # include <asm/siginfo.h>
  17 # define __have_siginfo_t 1
  18 # define __have_sigval_t 1
  19 # define __have_sigevent_t 1
  20 #endif
  21
  22 #include <errno.h>
  23 #include <linux/filter.h>
  24 #include <sys/prctl.h>
  25 #include <sys/ptrace.h>
  26 #include <sys/user.h>
  27 #include <linux/prctl.h>
  28 #include <linux/ptrace.h>
  29 #include <linux/seccomp.h>
  30 #include <pthread.h>
  31 #include <semaphore.h>
  32 #include <signal.h>
  33 #include <stddef.h>
  34 #include <stdbool.h>
  35 #include <string.h>
  36 #include <time.h>
  37 #include <linux/elf.h>
  38 #include <sys/uio.h>
  39 #include <sys/utsname.h>
  40 #include <sys/fcntl.h>
  41 #include <sys/mman.h>
  42 #include <sys/times.h>
  43
  44 #define _GNU_SOURCE
  45 #include <unistd.h>
  46 #include <sys/syscall.h>
  47
  48 #include "../kselftest_harness.h"
  49
  50 #ifndef PR_SET_PTRACER
  51 # define PR_SET_PTRACER 0x59616d61
  52 #endif
  53
  54 #ifndef PR_SET_NO_NEW_PRIVS
  55 #define PR_SET_NO_NEW_PRIVS 38
  56 #define PR_GET_NO_NEW_PRIVS 39
  57 #endif
  58
  59 #ifndef PR_SECCOMP_EXT
  60 #define PR_SECCOMP_EXT 43
  61 #endif
  62
  63 #ifndef SECCOMP_EXT_ACT
  64 #define SECCOMP_EXT_ACT 1
  65 #endif
  66
  67 #ifndef SECCOMP_EXT_ACT_TSYNC
  68 #define SECCOMP_EXT_ACT_TSYNC 1
  69 #endif
  70
  71 #ifndef SECCOMP_MODE_STRICT
  72 #define SECCOMP_MODE_STRICT 1
  73 #endif
  74
  75 #ifndef SECCOMP_MODE_FILTER
  76 #define SECCOMP_MODE_FILTER 2
  77 #endif
  78
  79 #ifndef SECCOMP_RET_ALLOW
  80 struct seccomp_data {
  81         int nr;
  82         __u32 arch;
  83         __u64 instruction_pointer;
  84         __u64 args[6];
  85 };
  86 #endif
  87
  88 #ifndef SECCOMP_RET_KILL_PROCESS
  89 #define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process */
  90 #define SECCOMP_RET_KILL_THREAD  0x00000000U /* kill the thread */
  91 #endif
  92 #ifndef SECCOMP_RET_KILL
  93 #define SECCOMP_RET_KILL         SECCOMP_RET_KILL_THREAD
  94 #define SECCOMP_RET_TRAP         0x00030000U /* disallow and force a SIGSYS */
  95 #define SECCOMP_RET_ERRNO        0x00050000U /* returns an errno */
  96 #define SECCOMP_RET_TRACE        0x7ff00000U /* pass to a tracer or disallow */
  97 #define SECCOMP_RET_ALLOW        0x7fff0000U /* allow */
  98 #endif
  99 #ifndef SECCOMP_RET_LOG
 100 #define SECCOMP_RET_LOG          0x7ffc0000U /* allow after logging */
 101 #endif
 102
 103 #ifndef __NR_seccomp
 104 # if defined(__i386__)
 105 #  define __NR_seccomp 354
 106 # elif defined(__x86_64__)
 107 #  define __NR_seccomp 317
 108 # elif defined(__arm__)
 109 #  define __NR_seccomp 383
 110 # elif defined(__aarch64__)
 111 #  define __NR_seccomp 277
 112 # elif defined(__hppa__)
 113 #  define __NR_seccomp 338
 114 # elif defined(__powerpc__)
 115 #  define __NR_seccomp 358
 116 # elif defined(__s390__)
 117 #  define __NR_seccomp 348
 118 # else
 119 #  warning "seccomp syscall number unknown for this architecture"
 120 #  define __NR_seccomp 0xffff
 121 # endif
 122 #endif
 123
 124 #ifndef SECCOMP_SET_MODE_STRICT
 125 #define SECCOMP_SET_MODE_STRICT 0
 126 #endif
 127
 128 #ifndef SECCOMP_SET_MODE_FILTER
 129 #define SECCOMP_SET_MODE_FILTER 1
 130 #endif
 131
 132 #ifndef SECCOMP_GET_ACTION_AVAIL
 133 #define SECCOMP_GET_ACTION_AVAIL 2
 134 #endif
 135
 136 #ifndef SECCOMP_FILTER_FLAG_TSYNC
 137 #define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
 138 #endif
 139
 140 #ifndef SECCOMP_FILTER_FLAG_LOG
 141 #define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
 142 #endif
 143
 144 #ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
 145 #define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
 146 #endif
 147
 148 #ifndef PTRACE_SECCOMP_GET_METADATA
 149 #define PTRACE_SECCOMP_GET_METADATA     0x420d
 150
 151 struct seccomp_metadata {
 152         __u64 filter_off;       /* Input: which filter */
 153         __u64 flags;             /* Output: filter's flags */
 154 };
 155 #endif
 156
 157 #ifndef seccomp
 158 int seccomp(unsigned int op, unsigned int flags, void *args)
 159 {
 160         errno = 0;
 161         return syscall(__NR_seccomp, op, flags, args);
 162 }
 163 #endif
 164
 165 #if __BYTE_ORDER == __LITTLE_ENDIAN
 166 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]))
 167 #elif __BYTE_ORDER == __BIG_ENDIAN
 168 #define syscall_arg(_n) (offsetof(struct seccomp_data, args[_n]) + sizeof(__u32))
 169 #else
 170 #error "wut? Unknown __BYTE_ORDER?!"
 171 #endif
 172
 173 #define SIBLING_EXIT_UNKILLED   0xbadbeef
 174 #define SIBLING_EXIT_FAILURE    0xbadface
 175 #define SIBLING_EXIT_NEWPRIVS   0xbadfeed
 176
 177 TEST(mode_strict_support)
 178 {
 179         long ret;
 180
 181         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
 182         ASSERT_EQ(0, ret) {
 183                 TH_LOG("Kernel does not support CONFIG_SECCOMP");
 184         }
 185         syscall(__NR_exit, 0);
 186 }
 187
 188 TEST_SIGNAL(mode_strict_cannot_call_prctl, SIGKILL)
 189 {
 190         long ret;
 191
 192         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, NULL, NULL);
 193         ASSERT_EQ(0, ret) {
 194                 TH_LOG("Kernel does not support CONFIG_SECCOMP");
 195         }
 196         syscall(__NR_prctl, PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
 197                 NULL, NULL, NULL);
 198         EXPECT_FALSE(true) {
 199                 TH_LOG("Unreachable!");
 200         }
 201 }
 202
 203 /* Note! This doesn't test no new privs behavior */
 204 TEST(no_new_privs_support)
 205 {
 206         long ret;
 207
 208         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 209         EXPECT_EQ(0, ret) {
 210                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
 211         }
 212 }
 213
 214 /* Tests kernel support by checking for a copy_from_user() fault on NULL. */
 215 TEST(mode_filter_support)
 216 {
 217         long ret;
 218
 219         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
 220         ASSERT_EQ(0, ret) {
 221                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
 222         }
 223         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, NULL, NULL, NULL);
 224         EXPECT_EQ(-1, ret);
 225         EXPECT_EQ(EFAULT, errno) {
 226                 TH_LOG("Kernel does not support CONFIG_SECCOMP_FILTER!");
 227         }
 228 }
 229
 230 TEST(mode_filter_without_nnp)
 231 {
 232         struct sock_filter filter[] = {
 233                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 234         };
 235         struct sock_fprog prog = {
 236                 .len = (unsigned short)ARRAY_SIZE(filter),
 237                 .filter = filter,
 238         };
 239         long ret;
 240
 241         ret = prctl(PR_GET_NO_NEW_PRIVS, 0, NULL, 0, 0);
 242         ASSERT_LE(0, ret) {
 243                 TH_LOG("Expected 0 or unsupported for NO_NEW_PRIVS");
 244         }
 245         errno = 0;
 246         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 247         /* Succeeds with CAP_SYS_ADMIN, fails without */
 248         /* TODO(wad) check caps not euid */
 249         if (geteuid()) {
 250                 EXPECT_EQ(-1, ret);
 251                 EXPECT_EQ(EACCES, errno);
 252         } else {
 253                 EXPECT_EQ(0, ret);
 254         }
 255 }
 256
 257 #define MAX_INSNS_PER_PATH 32768
 258
 259 TEST(filter_size_limits)
 260 {
 261         int i;
 262         int count = BPF_MAXINSNS + 1;
 263         struct sock_filter allow[] = {
 264                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 265         };
 266         struct sock_filter *filter;
 267         struct sock_fprog prog = { };
 268         long ret;
 269
 270         filter = calloc(count, sizeof(*filter));
 271         ASSERT_NE(NULL, filter);
 272
 273         for (i = 0; i < count; i++)
 274                 filter[i] = allow[0];
 275
 276         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 277         ASSERT_EQ(0, ret);
 278
 279         prog.filter = filter;
 280         prog.len = count;
 281
 282         /* Too many filter instructions in a single filter. */
 283         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 284         ASSERT_NE(0, ret) {
 285                 TH_LOG("Installing %d insn filter was allowed", prog.len);
 286         }
 287
 288         /* One less is okay, though. */
 289         prog.len -= 1;
 290         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 291         ASSERT_EQ(0, ret) {
 292                 TH_LOG("Installing %d insn filter wasn't allowed", prog.len);
 293         }
 294 }
 295
 296 TEST(filter_chain_limits)
 297 {
 298         int i;
 299         int count = BPF_MAXINSNS;
 300         struct sock_filter allow[] = {
 301                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 302         };
 303         struct sock_filter *filter;
 304         struct sock_fprog prog = { };
 305         long ret;
 306
 307         filter = calloc(count, sizeof(*filter));
 308         ASSERT_NE(NULL, filter);
 309
 310         for (i = 0; i < count; i++)
 311                 filter[i] = allow[0];
 312
 313         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 314         ASSERT_EQ(0, ret);
 315
 316         prog.filter = filter;
 317         prog.len = 1;
 318
 319         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 320         ASSERT_EQ(0, ret);
 321
 322         prog.len = count;
 323
 324         /* Too many total filter instructions. */
 325         for (i = 0; i < MAX_INSNS_PER_PATH; i++) {
 326                 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 327                 if (ret != 0)
 328                         break;
 329         }
 330         ASSERT_NE(0, ret) {
 331                 TH_LOG("Allowed %d %d-insn filters (total with penalties:%d)",
 332                        i, count, i * (count + 4));
 333         }
 334 }
 335
 336 TEST(mode_filter_cannot_move_to_strict)
 337 {
 338         struct sock_filter filter[] = {
 339                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 340         };
 341         struct sock_fprog prog = {
 342                 .len = (unsigned short)ARRAY_SIZE(filter),
 343                 .filter = filter,
 344         };
 345         long ret;
 346
 347         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 348         ASSERT_EQ(0, ret);
 349
 350         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 351         ASSERT_EQ(0, ret);
 352
 353         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, NULL, 0, 0);
 354         EXPECT_EQ(-1, ret);
 355         EXPECT_EQ(EINVAL, errno);
 356 }
 357
 358
 359 TEST(mode_filter_get_seccomp)
 360 {
 361         struct sock_filter filter[] = {
 362                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 363         };
 364         struct sock_fprog prog = {
 365                 .len = (unsigned short)ARRAY_SIZE(filter),
 366                 .filter = filter,
 367         };
 368         long ret;
 369
 370         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 371         ASSERT_EQ(0, ret);
 372
 373         ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
 374         EXPECT_EQ(0, ret);
 375
 376         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
 377         ASSERT_EQ(0, ret);
 378
 379         ret = prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
 380         EXPECT_EQ(2, ret);
 381 }
 382
 383
 384 TEST(ALLOW_all)
 385 {
 386         struct sock_filter filter[] = {
 387                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 388         };
 389         struct sock_fprog prog = {
 390                 .len = (unsigned short)ARRAY_SIZE(filter),
 391                 .filter = filter,
 392         };
 393         long ret;
 394
 395         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 396         ASSERT_EQ(0, ret);
 397
 398         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 399         ASSERT_EQ(0, ret);
 400 }
 401
 402 TEST(empty_prog)
 403 {
 404         struct sock_filter filter[] = {
 405         };
 406         struct sock_fprog prog = {
 407                 .len = (unsigned short)ARRAY_SIZE(filter),
 408                 .filter = filter,
 409         };
 410         long ret;
 411
 412         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 413         ASSERT_EQ(0, ret);
 414
 415         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 416         EXPECT_EQ(-1, ret);
 417         EXPECT_EQ(EINVAL, errno);
 418 }
 419
 420 TEST(log_all)
 421 {
 422         struct sock_filter filter[] = {
 423                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
 424         };
 425         struct sock_fprog prog = {
 426                 .len = (unsigned short)ARRAY_SIZE(filter),
 427                 .filter = filter,
 428         };
 429         long ret;
 430         pid_t parent = getppid();
 431
 432         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 433         ASSERT_EQ(0, ret);
 434
 435         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 436         ASSERT_EQ(0, ret);
 437
 438         /* getppid() should succeed and be logged (no check for logging) */
 439         EXPECT_EQ(parent, syscall(__NR_getppid));
 440 }
 441
 442 TEST_SIGNAL(unknown_ret_is_kill_inside, SIGSYS)
 443 {
 444         struct sock_filter filter[] = {
 445                 BPF_STMT(BPF_RET|BPF_K, 0x10000000U),
 446         };
 447         struct sock_fprog prog = {
 448                 .len = (unsigned short)ARRAY_SIZE(filter),
 449                 .filter = filter,
 450         };
 451         long ret;
 452
 453         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 454         ASSERT_EQ(0, ret);
 455
 456         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 457         ASSERT_EQ(0, ret);
 458         EXPECT_EQ(0, syscall(__NR_getpid)) {
 459                 TH_LOG("getpid() shouldn't ever return");
 460         }
 461 }
 462
 463 /* return code >= 0x80000000 is unused. */
 464 TEST_SIGNAL(unknown_ret_is_kill_above_allow, SIGSYS)
 465 {
 466         struct sock_filter filter[] = {
 467                 BPF_STMT(BPF_RET|BPF_K, 0x90000000U),
 468         };
 469         struct sock_fprog prog = {
 470                 .len = (unsigned short)ARRAY_SIZE(filter),
 471                 .filter = filter,
 472         };
 473         long ret;
 474
 475         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 476         ASSERT_EQ(0, ret);
 477
 478         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 479         ASSERT_EQ(0, ret);
 480         EXPECT_EQ(0, syscall(__NR_getpid)) {
 481                 TH_LOG("getpid() shouldn't ever return");
 482         }
 483 }
 484
 485 TEST_SIGNAL(KILL_all, SIGSYS)
 486 {
 487         struct sock_filter filter[] = {
 488                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
 489         };
 490         struct sock_fprog prog = {
 491                 .len = (unsigned short)ARRAY_SIZE(filter),
 492                 .filter = filter,
 493         };
 494         long ret;
 495
 496         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 497         ASSERT_EQ(0, ret);
 498
 499         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 500         ASSERT_EQ(0, ret);
 501 }
 502
 503 TEST_SIGNAL(KILL_one, SIGSYS)
 504 {
 505         struct sock_filter filter[] = {
 506                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 507                         offsetof(struct seccomp_data, nr)),
 508                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
 509                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
 510                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 511         };
 512         struct sock_fprog prog = {
 513                 .len = (unsigned short)ARRAY_SIZE(filter),
 514                 .filter = filter,
 515         };
 516         long ret;
 517         pid_t parent = getppid();
 518
 519         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 520         ASSERT_EQ(0, ret);
 521
 522         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 523         ASSERT_EQ(0, ret);
 524
 525         EXPECT_EQ(parent, syscall(__NR_getppid));
 526         /* getpid() should never return. */
 527         EXPECT_EQ(0, syscall(__NR_getpid));
 528 }
 529
 530 TEST_SIGNAL(KILL_one_arg_one, SIGSYS)
 531 {
 532         void *fatal_address;
 533         struct sock_filter filter[] = {
 534                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 535                         offsetof(struct seccomp_data, nr)),
 536                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_times, 1, 0),
 537                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 538                 /* Only both with lower 32-bit for now. */
 539                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(0)),
 540                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K,
 541                         (unsigned long)&fatal_address, 0, 1),
 542                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
 543                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 544         };
 545         struct sock_fprog prog = {
 546                 .len = (unsigned short)ARRAY_SIZE(filter),
 547                 .filter = filter,
 548         };
 549         long ret;
 550         pid_t parent = getppid();
 551         struct tms timebuf;
 552         clock_t clock = times(&timebuf);
 553
 554         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 555         ASSERT_EQ(0, ret);
 556
 557         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 558         ASSERT_EQ(0, ret);
 559
 560         EXPECT_EQ(parent, syscall(__NR_getppid));
 561         EXPECT_LE(clock, syscall(__NR_times, &timebuf));
 562         /* times() should never return. */
 563         EXPECT_EQ(0, syscall(__NR_times, &fatal_address));
 564 }
 565
 566 TEST_SIGNAL(KILL_one_arg_six, SIGSYS)
 567 {
 568 #ifndef __NR_mmap2
 569         int sysno = __NR_mmap;
 570 #else
 571         int sysno = __NR_mmap2;
 572 #endif
 573         struct sock_filter filter[] = {
 574                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 575                         offsetof(struct seccomp_data, nr)),
 576                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, sysno, 1, 0),
 577                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 578                 /* Only both with lower 32-bit for now. */
 579                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(5)),
 580                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 0x0C0FFEE, 0, 1),
 581                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
 582                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 583         };
 584         struct sock_fprog prog = {
 585                 .len = (unsigned short)ARRAY_SIZE(filter),
 586                 .filter = filter,
 587         };
 588         long ret;
 589         pid_t parent = getppid();
 590         int fd;
 591         void *map1, *map2;
 592         int page_size = sysconf(_SC_PAGESIZE);
 593
 594         ASSERT_LT(0, page_size);
 595
 596         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 597         ASSERT_EQ(0, ret);
 598
 599         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 600         ASSERT_EQ(0, ret);
 601
 602         fd = open("/dev/zero", O_RDONLY);
 603         ASSERT_NE(-1, fd);
 604
 605         EXPECT_EQ(parent, syscall(__NR_getppid));
 606         map1 = (void *)syscall(sysno,
 607                 NULL, page_size, PROT_READ, MAP_PRIVATE, fd, page_size);
 608         EXPECT_NE(MAP_FAILED, map1);
 609         /* mmap2() should never return. */
 610         map2 = (void *)syscall(sysno,
 611                  NULL, page_size, PROT_READ, MAP_PRIVATE, fd, 0x0C0FFEE);
 612         EXPECT_EQ(MAP_FAILED, map2);
 613
 614         /* The test failed, so clean up the resources. */
 615         munmap(map1, page_size);
 616         munmap(map2, page_size);
 617         close(fd);
 618 }
 619
 620 /* This is a thread task to die via seccomp filter violation. */
 621 void *kill_thread(void *data)
 622 {
 623         bool die = (bool)data;
 624
 625         if (die) {
 626                 prctl(PR_GET_SECCOMP, 0, 0, 0, 0);
 627                 return (void *)SIBLING_EXIT_FAILURE;
 628         }
 629
 630         return (void *)SIBLING_EXIT_UNKILLED;
 631 }
 632
 633 /* Prepare a thread that will kill itself or both of us. */
 634 void kill_thread_or_group(struct __test_metadata *_metadata, bool kill_process)
 635 {
 636         pthread_t thread;
 637         void *status;
 638         /* Kill only when calling __NR_prctl. */
 639         struct sock_filter filter_thread[] = {
 640                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 641                         offsetof(struct seccomp_data, nr)),
 642                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
 643                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_THREAD),
 644                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 645         };
 646         struct sock_fprog prog_thread = {
 647                 .len = (unsigned short)ARRAY_SIZE(filter_thread),
 648                 .filter = filter_thread,
 649         };
 650         struct sock_filter filter_process[] = {
 651                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 652                         offsetof(struct seccomp_data, nr)),
 653                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
 654                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL_PROCESS),
 655                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 656         };
 657         struct sock_fprog prog_process = {
 658                 .len = (unsigned short)ARRAY_SIZE(filter_process),
 659                 .filter = filter_process,
 660         };
 661
 662         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
 663                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
 664         }
 665
 666         ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0,
 667                              kill_process ? &prog_process : &prog_thread));
 668
 669         /*
 670          * Add the KILL_THREAD rule again to make sure that the KILL_PROCESS
 671          * flag cannot be downgraded by a new filter.
 672          */
 673         ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog_thread));
 674
 675         /* Start a thread that will exit immediately. */
 676         ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)false));
 677         ASSERT_EQ(0, pthread_join(thread, &status));
 678         ASSERT_EQ(SIBLING_EXIT_UNKILLED, (unsigned long)status);
 679
 680         /* Start a thread that will die immediately. */
 681         ASSERT_EQ(0, pthread_create(&thread, NULL, kill_thread, (void *)true));
 682         ASSERT_EQ(0, pthread_join(thread, &status));
 683         ASSERT_NE(SIBLING_EXIT_FAILURE, (unsigned long)status);
 684
 685         /*
 686          * If we get here, only the spawned thread died. Let the parent know
 687          * the whole process didn't die (i.e. this thread, the spawner,
 688          * stayed running).
 689          */
 690         exit(42);
 691 }
 692
 693 TEST(KILL_thread)
 694 {
 695         int status;
 696         pid_t child_pid;
 697
 698         child_pid = fork();
 699         ASSERT_LE(0, child_pid);
 700         if (child_pid == 0) {
 701                 kill_thread_or_group(_metadata, false);
 702                 _exit(38);
 703         }
 704
 705         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
 706
 707         /* If only the thread was killed, we'll see exit 42. */
 708         ASSERT_TRUE(WIFEXITED(status));
 709         ASSERT_EQ(42, WEXITSTATUS(status));
 710 }
 711
 712 TEST(KILL_process)
 713 {
 714         int status;
 715         pid_t child_pid;
 716
 717         child_pid = fork();
 718         ASSERT_LE(0, child_pid);
 719         if (child_pid == 0) {
 720                 kill_thread_or_group(_metadata, true);
 721                 _exit(38);
 722         }
 723
 724         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
 725
 726         /* If the entire process was killed, we'll see SIGSYS. */
 727         ASSERT_TRUE(WIFSIGNALED(status));
 728         ASSERT_EQ(SIGSYS, WTERMSIG(status));
 729 }
 730
 731 /* TODO(wad) add 64-bit versus 32-bit arg tests. */
 732 TEST(arg_out_of_range)
 733 {
 734         struct sock_filter filter[] = {
 735                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_arg(6)),
 736                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 737         };
 738         struct sock_fprog prog = {
 739                 .len = (unsigned short)ARRAY_SIZE(filter),
 740                 .filter = filter,
 741         };
 742         long ret;
 743
 744         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 745         ASSERT_EQ(0, ret);
 746
 747         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog);
 748         EXPECT_EQ(-1, ret);
 749         EXPECT_EQ(EINVAL, errno);
 750 }
 751
 752 #define ERRNO_FILTER(name, errno)                                       \
 753         struct sock_filter _read_filter_##name[] = {                    \
 754                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,                          \
 755                         offsetof(struct seccomp_data, nr)),             \
 756                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),       \
 757                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | errno),     \
 758                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),             \
 759         };                                                              \
 760         struct sock_fprog prog_##name = {                               \
 761                 .len = (unsigned short)ARRAY_SIZE(_read_filter_##name), \
 762                 .filter = _read_filter_##name,                          \
 763         }
 764
 765 /* Make sure basic errno values are correctly passed through a filter. */
 766 TEST(ERRNO_valid)
 767 {
 768         ERRNO_FILTER(valid, E2BIG);
 769         long ret;
 770         pid_t parent = getppid();
 771
 772         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 773         ASSERT_EQ(0, ret);
 774
 775         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_valid);
 776         ASSERT_EQ(0, ret);
 777
 778         EXPECT_EQ(parent, syscall(__NR_getppid));
 779         EXPECT_EQ(-1, read(0, NULL, 0));
 780         EXPECT_EQ(E2BIG, errno);
 781 }
 782
 783 /* Make sure an errno of zero is correctly handled by the arch code. */
 784 TEST(ERRNO_zero)
 785 {
 786         ERRNO_FILTER(zero, 0);
 787         long ret;
 788         pid_t parent = getppid();
 789
 790         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 791         ASSERT_EQ(0, ret);
 792
 793         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_zero);
 794         ASSERT_EQ(0, ret);
 795
 796         EXPECT_EQ(parent, syscall(__NR_getppid));
 797         /* "errno" of 0 is ok. */
 798         EXPECT_EQ(0, read(0, NULL, 0));
 799 }
 800
 801 /*
 802  * The SECCOMP_RET_DATA mask is 16 bits wide, but errno is smaller.
 803  * This tests that the errno value gets capped correctly, fixed by
 804  * 580c57f10768 ("seccomp: cap SECCOMP_RET_ERRNO data to MAX_ERRNO").
 805  */
 806 TEST(ERRNO_capped)
 807 {
 808         ERRNO_FILTER(capped, 4096);
 809         long ret;
 810         pid_t parent = getppid();
 811
 812         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 813         ASSERT_EQ(0, ret);
 814
 815         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_capped);
 816         ASSERT_EQ(0, ret);
 817
 818         EXPECT_EQ(parent, syscall(__NR_getppid));
 819         EXPECT_EQ(-1, read(0, NULL, 0));
 820         EXPECT_EQ(4095, errno);
 821 }
 822
 823 /*
 824  * Filters are processed in reverse order: last applied is executed first.
 825  * Since only the SECCOMP_RET_ACTION mask is tested for return values, the
 826  * SECCOMP_RET_DATA mask results will follow the most recently applied
 827  * matching filter return (and not the lowest or highest value).
 828  */
 829 TEST(ERRNO_order)
 830 {
 831         ERRNO_FILTER(first,  11);
 832         ERRNO_FILTER(second, 13);
 833         ERRNO_FILTER(third,  12);
 834         long ret;
 835         pid_t parent = getppid();
 836
 837         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 838         ASSERT_EQ(0, ret);
 839
 840         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_first);
 841         ASSERT_EQ(0, ret);
 842
 843         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_second);
 844         ASSERT_EQ(0, ret);
 845
 846         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog_third);
 847         ASSERT_EQ(0, ret);
 848
 849         EXPECT_EQ(parent, syscall(__NR_getppid));
 850         EXPECT_EQ(-1, read(0, NULL, 0));
 851         EXPECT_EQ(12, errno);
 852 }
 853
 854 FIXTURE_DATA(TRAP) {
 855         struct sock_fprog prog;
 856 };
 857
 858 FIXTURE_SETUP(TRAP)
 859 {
 860         struct sock_filter filter[] = {
 861                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 862                         offsetof(struct seccomp_data, nr)),
 863                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
 864                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
 865                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 866         };
 867
 868         memset(&self->prog, 0, sizeof(self->prog));
 869         self->prog.filter = malloc(sizeof(filter));
 870         ASSERT_NE(NULL, self->prog.filter);
 871         memcpy(self->prog.filter, filter, sizeof(filter));
 872         self->prog.len = (unsigned short)ARRAY_SIZE(filter);
 873 }
 874
 875 FIXTURE_TEARDOWN(TRAP)
 876 {
 877         if (self->prog.filter)
 878                 free(self->prog.filter);
 879 }
 880
 881 TEST_F_SIGNAL(TRAP, dfl, SIGSYS)
 882 {
 883         long ret;
 884
 885         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 886         ASSERT_EQ(0, ret);
 887
 888         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
 889         ASSERT_EQ(0, ret);
 890         syscall(__NR_getpid);
 891 }
 892
 893 /* Ensure that SIGSYS overrides SIG_IGN */
 894 TEST_F_SIGNAL(TRAP, ign, SIGSYS)
 895 {
 896         long ret;
 897
 898         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 899         ASSERT_EQ(0, ret);
 900
 901         signal(SIGSYS, SIG_IGN);
 902
 903         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
 904         ASSERT_EQ(0, ret);
 905         syscall(__NR_getpid);
 906 }
 907
 908 static siginfo_t TRAP_info;
 909 static volatile int TRAP_nr;
 910 static void TRAP_action(int nr, siginfo_t *info, void *void_context)
 911 {
 912         memcpy(&TRAP_info, info, sizeof(TRAP_info));
 913         TRAP_nr = nr;
 914 }
 915
 916 TEST_F(TRAP, handler)
 917 {
 918         int ret, test;
 919         struct sigaction act;
 920         sigset_t mask;
 921
 922         memset(&act, 0, sizeof(act));
 923         sigemptyset(&mask);
 924         sigaddset(&mask, SIGSYS);
 925
 926         act.sa_sigaction = &TRAP_action;
 927         act.sa_flags = SA_SIGINFO;
 928         ret = sigaction(SIGSYS, &act, NULL);
 929         ASSERT_EQ(0, ret) {
 930                 TH_LOG("sigaction failed");
 931         }
 932         ret = sigprocmask(SIG_UNBLOCK, &mask, NULL);
 933         ASSERT_EQ(0, ret) {
 934                 TH_LOG("sigprocmask failed");
 935         }
 936
 937         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
 938         ASSERT_EQ(0, ret);
 939         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog);
 940         ASSERT_EQ(0, ret);
 941         TRAP_nr = 0;
 942         memset(&TRAP_info, 0, sizeof(TRAP_info));
 943         /* Expect the registers to be rolled back. (nr = error) may vary
 944          * based on arch. */
 945         ret = syscall(__NR_getpid);
 946         /* Silence gcc warning about volatile. */
 947         test = TRAP_nr;
 948         EXPECT_EQ(SIGSYS, test);
 949         struct local_sigsys {
 950                 void *_call_addr;       /* calling user insn */
 951                 int _syscall;           /* triggering system call number */
 952                 unsigned int _arch;     /* AUDIT_ARCH_* of syscall */
 953         } *sigsys = (struct local_sigsys *)
 954 #ifdef si_syscall
 955                 &(TRAP_info.si_call_addr);
 956 #else
 957                 &TRAP_info.si_pid;
 958 #endif
 959         EXPECT_EQ(__NR_getpid, sigsys->_syscall);
 960         /* Make sure arch is non-zero. */
 961         EXPECT_NE(0, sigsys->_arch);
 962         EXPECT_NE(0, (unsigned long)sigsys->_call_addr);
 963 }
 964
 965 FIXTURE_DATA(precedence) {
 966         struct sock_fprog allow;
 967         struct sock_fprog log;
 968         struct sock_fprog trace;
 969         struct sock_fprog error;
 970         struct sock_fprog trap;
 971         struct sock_fprog kill;
 972 };
 973
 974 FIXTURE_SETUP(precedence)
 975 {
 976         struct sock_filter allow_insns[] = {
 977                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 978         };
 979         struct sock_filter log_insns[] = {
 980                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 981                         offsetof(struct seccomp_data, nr)),
 982                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
 983                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 984                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_LOG),
 985         };
 986         struct sock_filter trace_insns[] = {
 987                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 988                         offsetof(struct seccomp_data, nr)),
 989                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
 990                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 991                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE),
 992         };
 993         struct sock_filter error_insns[] = {
 994                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
 995                         offsetof(struct seccomp_data, nr)),
 996                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
 997                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
 998                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO),
 999         };
1000         struct sock_filter trap_insns[] = {
1001                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1002                         offsetof(struct seccomp_data, nr)),
1003                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1004                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1005                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP),
1006         };
1007         struct sock_filter kill_insns[] = {
1008                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1009                         offsetof(struct seccomp_data, nr)),
1010                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 1, 0),
1011                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1012                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1013         };
1014
1015         memset(self, 0, sizeof(*self));
1016 #define FILTER_ALLOC(_x) \
1017         self->_x.filter = malloc(sizeof(_x##_insns)); \
1018         ASSERT_NE(NULL, self->_x.filter); \
1019         memcpy(self->_x.filter, &_x##_insns, sizeof(_x##_insns)); \
1020         self->_x.len = (unsigned short)ARRAY_SIZE(_x##_insns)
1021         FILTER_ALLOC(allow);
1022         FILTER_ALLOC(log);
1023         FILTER_ALLOC(trace);
1024         FILTER_ALLOC(error);
1025         FILTER_ALLOC(trap);
1026         FILTER_ALLOC(kill);
1027 }
1028
1029 FIXTURE_TEARDOWN(precedence)
1030 {
1031 #define FILTER_FREE(_x) if (self->_x.filter) free(self->_x.filter)
1032         FILTER_FREE(allow);
1033         FILTER_FREE(log);
1034         FILTER_FREE(trace);
1035         FILTER_FREE(error);
1036         FILTER_FREE(trap);
1037         FILTER_FREE(kill);
1038 }
1039
1040 TEST_F(precedence, allow_ok)
1041 {
1042         pid_t parent, res = 0;
1043         long ret;
1044
1045         parent = getppid();
1046         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1047         ASSERT_EQ(0, ret);
1048
1049         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1050         ASSERT_EQ(0, ret);
1051         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1052         ASSERT_EQ(0, ret);
1053         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1054         ASSERT_EQ(0, ret);
1055         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1056         ASSERT_EQ(0, ret);
1057         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1058         ASSERT_EQ(0, ret);
1059         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1060         ASSERT_EQ(0, ret);
1061         /* Should work just fine. */
1062         res = syscall(__NR_getppid);
1063         EXPECT_EQ(parent, res);
1064 }
1065
1066 TEST_F_SIGNAL(precedence, kill_is_highest, SIGSYS)
1067 {
1068         pid_t parent, res = 0;
1069         long ret;
1070
1071         parent = getppid();
1072         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1073         ASSERT_EQ(0, ret);
1074
1075         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1076         ASSERT_EQ(0, ret);
1077         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1078         ASSERT_EQ(0, ret);
1079         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1080         ASSERT_EQ(0, ret);
1081         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1082         ASSERT_EQ(0, ret);
1083         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1084         ASSERT_EQ(0, ret);
1085         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1086         ASSERT_EQ(0, ret);
1087         /* Should work just fine. */
1088         res = syscall(__NR_getppid);
1089         EXPECT_EQ(parent, res);
1090         /* getpid() should never return. */
1091         res = syscall(__NR_getpid);
1092         EXPECT_EQ(0, res);
1093 }
1094
1095 TEST_F_SIGNAL(precedence, kill_is_highest_in_any_order, SIGSYS)
1096 {
1097         pid_t parent;
1098         long ret;
1099
1100         parent = getppid();
1101         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1102         ASSERT_EQ(0, ret);
1103
1104         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1105         ASSERT_EQ(0, ret);
1106         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->kill);
1107         ASSERT_EQ(0, ret);
1108         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1109         ASSERT_EQ(0, ret);
1110         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1111         ASSERT_EQ(0, ret);
1112         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1113         ASSERT_EQ(0, ret);
1114         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1115         ASSERT_EQ(0, ret);
1116         /* Should work just fine. */
1117         EXPECT_EQ(parent, syscall(__NR_getppid));
1118         /* getpid() should never return. */
1119         EXPECT_EQ(0, syscall(__NR_getpid));
1120 }
1121
1122 TEST_F_SIGNAL(precedence, trap_is_second, SIGSYS)
1123 {
1124         pid_t parent;
1125         long ret;
1126
1127         parent = getppid();
1128         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1129         ASSERT_EQ(0, ret);
1130
1131         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1132         ASSERT_EQ(0, ret);
1133         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1134         ASSERT_EQ(0, ret);
1135         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1136         ASSERT_EQ(0, ret);
1137         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1138         ASSERT_EQ(0, ret);
1139         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1140         ASSERT_EQ(0, ret);
1141         /* Should work just fine. */
1142         EXPECT_EQ(parent, syscall(__NR_getppid));
1143         /* getpid() should never return. */
1144         EXPECT_EQ(0, syscall(__NR_getpid));
1145 }
1146
1147 TEST_F_SIGNAL(precedence, trap_is_second_in_any_order, SIGSYS)
1148 {
1149         pid_t parent;
1150         long ret;
1151
1152         parent = getppid();
1153         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1154         ASSERT_EQ(0, ret);
1155
1156         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1157         ASSERT_EQ(0, ret);
1158         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trap);
1159         ASSERT_EQ(0, ret);
1160         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1161         ASSERT_EQ(0, ret);
1162         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1163         ASSERT_EQ(0, ret);
1164         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1165         ASSERT_EQ(0, ret);
1166         /* Should work just fine. */
1167         EXPECT_EQ(parent, syscall(__NR_getppid));
1168         /* getpid() should never return. */
1169         EXPECT_EQ(0, syscall(__NR_getpid));
1170 }
1171
1172 TEST_F(precedence, errno_is_third)
1173 {
1174         pid_t parent;
1175         long ret;
1176
1177         parent = getppid();
1178         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1179         ASSERT_EQ(0, ret);
1180
1181         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1182         ASSERT_EQ(0, ret);
1183         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1184         ASSERT_EQ(0, ret);
1185         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1186         ASSERT_EQ(0, ret);
1187         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1188         ASSERT_EQ(0, ret);
1189         /* Should work just fine. */
1190         EXPECT_EQ(parent, syscall(__NR_getppid));
1191         EXPECT_EQ(0, syscall(__NR_getpid));
1192 }
1193
1194 TEST_F(precedence, errno_is_third_in_any_order)
1195 {
1196         pid_t parent;
1197         long ret;
1198
1199         parent = getppid();
1200         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1201         ASSERT_EQ(0, ret);
1202
1203         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1204         ASSERT_EQ(0, ret);
1205         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->error);
1206         ASSERT_EQ(0, ret);
1207         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1208         ASSERT_EQ(0, ret);
1209         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1210         ASSERT_EQ(0, ret);
1211         /* Should work just fine. */
1212         EXPECT_EQ(parent, syscall(__NR_getppid));
1213         EXPECT_EQ(0, syscall(__NR_getpid));
1214 }
1215
1216 TEST_F(precedence, trace_is_fourth)
1217 {
1218         pid_t parent;
1219         long ret;
1220
1221         parent = getppid();
1222         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1223         ASSERT_EQ(0, ret);
1224
1225         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1226         ASSERT_EQ(0, ret);
1227         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1228         ASSERT_EQ(0, ret);
1229         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1230         ASSERT_EQ(0, ret);
1231         /* Should work just fine. */
1232         EXPECT_EQ(parent, syscall(__NR_getppid));
1233         /* No ptracer */
1234         EXPECT_EQ(-1, syscall(__NR_getpid));
1235 }
1236
1237 TEST_F(precedence, trace_is_fourth_in_any_order)
1238 {
1239         pid_t parent;
1240         long ret;
1241
1242         parent = getppid();
1243         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1244         ASSERT_EQ(0, ret);
1245
1246         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->trace);
1247         ASSERT_EQ(0, ret);
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         /* Should work just fine. */
1253         EXPECT_EQ(parent, syscall(__NR_getppid));
1254         /* No ptracer */
1255         EXPECT_EQ(-1, syscall(__NR_getpid));
1256 }
1257
1258 TEST_F(precedence, log_is_fifth)
1259 {
1260         pid_t mypid, parent;
1261         long ret;
1262
1263         mypid = getpid();
1264         parent = getppid();
1265         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1266         ASSERT_EQ(0, ret);
1267
1268         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1269         ASSERT_EQ(0, ret);
1270         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1271         ASSERT_EQ(0, ret);
1272         /* Should work just fine. */
1273         EXPECT_EQ(parent, syscall(__NR_getppid));
1274         /* Should also work just fine */
1275         EXPECT_EQ(mypid, syscall(__NR_getpid));
1276 }
1277
1278 TEST_F(precedence, log_is_fifth_in_any_order)
1279 {
1280         pid_t mypid, parent;
1281         long ret;
1282
1283         mypid = getpid();
1284         parent = getppid();
1285         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1286         ASSERT_EQ(0, ret);
1287
1288         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->log);
1289         ASSERT_EQ(0, ret);
1290         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->allow);
1291         ASSERT_EQ(0, ret);
1292         /* Should work just fine. */
1293         EXPECT_EQ(parent, syscall(__NR_getppid));
1294         /* Should also work just fine */
1295         EXPECT_EQ(mypid, syscall(__NR_getpid));
1296 }
1297
1298 #ifndef PTRACE_O_TRACESECCOMP
1299 #define PTRACE_O_TRACESECCOMP   0x00000080
1300 #endif
1301
1302 /* Catch the Ubuntu 12.04 value error. */
1303 #if PTRACE_EVENT_SECCOMP != 7
1304 #undef PTRACE_EVENT_SECCOMP
1305 #endif
1306
1307 #ifndef PTRACE_EVENT_SECCOMP
1308 #define PTRACE_EVENT_SECCOMP 7
1309 #endif
1310
1311 #define IS_SECCOMP_EVENT(status) ((status >> 16) == PTRACE_EVENT_SECCOMP)
1312 bool tracer_running;
1313 void tracer_stop(int sig)
1314 {
1315         tracer_running = false;
1316 }
1317
1318 typedef void tracer_func_t(struct __test_metadata *_metadata,
1319                            pid_t tracee, int status, void *args);
1320
1321 void start_tracer(struct __test_metadata *_metadata, int fd, pid_t tracee,
1322             tracer_func_t tracer_func, void *args, bool ptrace_syscall)
1323 {
1324         int ret = -1;
1325         struct sigaction action = {
1326                 .sa_handler = tracer_stop,
1327         };
1328
1329         /* Allow external shutdown. */
1330         tracer_running = true;
1331         ASSERT_EQ(0, sigaction(SIGUSR1, &action, NULL));
1332
1333         errno = 0;
1334         while (ret == -1 && errno != EINVAL)
1335                 ret = ptrace(PTRACE_ATTACH, tracee, NULL, 0);
1336         ASSERT_EQ(0, ret) {
1337                 kill(tracee, SIGKILL);
1338         }
1339         /* Wait for attach stop */
1340         wait(NULL);
1341
1342         ret = ptrace(PTRACE_SETOPTIONS, tracee, NULL, ptrace_syscall ?
1343                                                       PTRACE_O_TRACESYSGOOD :
1344                                                       PTRACE_O_TRACESECCOMP);
1345         ASSERT_EQ(0, ret) {
1346                 TH_LOG("Failed to set PTRACE_O_TRACESECCOMP");
1347                 kill(tracee, SIGKILL);
1348         }
1349         ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1350                      tracee, NULL, 0);
1351         ASSERT_EQ(0, ret);
1352
1353         /* Unblock the tracee */
1354         ASSERT_EQ(1, write(fd, "A", 1));
1355         ASSERT_EQ(0, close(fd));
1356
1357         /* Run until we're shut down. Must assert to stop execution. */
1358         while (tracer_running) {
1359                 int status;
1360
1361                 if (wait(&status) != tracee)
1362                         continue;
1363                 if (WIFSIGNALED(status) || WIFEXITED(status))
1364                         /* Child is dead. Time to go. */
1365                         return;
1366
1367                 /* Check if this is a seccomp event. */
1368                 ASSERT_EQ(!ptrace_syscall, IS_SECCOMP_EVENT(status));
1369
1370                 tracer_func(_metadata, tracee, status, args);
1371
1372                 ret = ptrace(ptrace_syscall ? PTRACE_SYSCALL : PTRACE_CONT,
1373                              tracee, NULL, 0);
1374                 ASSERT_EQ(0, ret);
1375         }
1376         /* Directly report the status of our test harness results. */
1377         syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS : EXIT_FAILURE);
1378 }
1379
1380 /* Common tracer setup/teardown functions. */
1381 void cont_handler(int num)
1382 { }
1383 pid_t setup_trace_fixture(struct __test_metadata *_metadata,
1384                           tracer_func_t func, void *args, bool ptrace_syscall)
1385 {
1386         char sync;
1387         int pipefd[2];
1388         pid_t tracer_pid;
1389         pid_t tracee = getpid();
1390
1391         /* Setup a pipe for clean synchronization. */
1392         ASSERT_EQ(0, pipe(pipefd));
1393
1394         /* Fork a child which we'll promote to tracer */
1395         tracer_pid = fork();
1396         ASSERT_LE(0, tracer_pid);
1397         signal(SIGALRM, cont_handler);
1398         if (tracer_pid == 0) {
1399                 close(pipefd[0]);
1400                 start_tracer(_metadata, pipefd[1], tracee, func, args,
1401                              ptrace_syscall);
1402                 syscall(__NR_exit, 0);
1403         }
1404         close(pipefd[1]);
1405         prctl(PR_SET_PTRACER, tracer_pid, 0, 0, 0);
1406         read(pipefd[0], &sync, 1);
1407         close(pipefd[0]);
1408
1409         return tracer_pid;
1410 }
1411 void teardown_trace_fixture(struct __test_metadata *_metadata,
1412                             pid_t tracer)
1413 {
1414         if (tracer) {
1415                 int status;
1416                 /*
1417                  * Extract the exit code from the other process and
1418                  * adopt it for ourselves in case its asserts failed.
1419                  */
1420                 ASSERT_EQ(0, kill(tracer, SIGUSR1));
1421                 ASSERT_EQ(tracer, waitpid(tracer, &status, 0));
1422                 if (WEXITSTATUS(status))
1423                         _metadata->passed = 0;
1424         }
1425 }
1426
1427 /* "poke" tracer arguments and function. */
1428 struct tracer_args_poke_t {
1429         unsigned long poke_addr;
1430 };
1431
1432 void tracer_poke(struct __test_metadata *_metadata, pid_t tracee, int status,
1433                  void *args)
1434 {
1435         int ret;
1436         unsigned long msg;
1437         struct tracer_args_poke_t *info = (struct tracer_args_poke_t *)args;
1438
1439         ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1440         EXPECT_EQ(0, ret);
1441         /* If this fails, don't try to recover. */
1442         ASSERT_EQ(0x1001, msg) {
1443                 kill(tracee, SIGKILL);
1444         }
1445         /*
1446          * Poke in the message.
1447          * Registers are not touched to try to keep this relatively arch
1448          * agnostic.
1449          */
1450         ret = ptrace(PTRACE_POKEDATA, tracee, info->poke_addr, 0x1001);
1451         EXPECT_EQ(0, ret);
1452 }
1453
1454 FIXTURE_DATA(TRACE_poke) {
1455         struct sock_fprog prog;
1456         pid_t tracer;
1457         long poked;
1458         struct tracer_args_poke_t tracer_args;
1459 };
1460
1461 FIXTURE_SETUP(TRACE_poke)
1462 {
1463         struct sock_filter filter[] = {
1464                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1465                         offsetof(struct seccomp_data, nr)),
1466                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
1467                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1001),
1468                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1469         };
1470
1471         self->poked = 0;
1472         memset(&self->prog, 0, sizeof(self->prog));
1473         self->prog.filter = malloc(sizeof(filter));
1474         ASSERT_NE(NULL, self->prog.filter);
1475         memcpy(self->prog.filter, filter, sizeof(filter));
1476         self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1477
1478         /* Set up tracer args. */
1479         self->tracer_args.poke_addr = (unsigned long)&self->poked;
1480
1481         /* Launch tracer. */
1482         self->tracer = setup_trace_fixture(_metadata, tracer_poke,
1483                                            &self->tracer_args, false);
1484 }
1485
1486 FIXTURE_TEARDOWN(TRACE_poke)
1487 {
1488         teardown_trace_fixture(_metadata, self->tracer);
1489         if (self->prog.filter)
1490                 free(self->prog.filter);
1491 }
1492
1493 TEST_F(TRACE_poke, read_has_side_effects)
1494 {
1495         ssize_t ret;
1496
1497         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1498         ASSERT_EQ(0, ret);
1499
1500         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1501         ASSERT_EQ(0, ret);
1502
1503         EXPECT_EQ(0, self->poked);
1504         ret = read(-1, NULL, 0);
1505         EXPECT_EQ(-1, ret);
1506         EXPECT_EQ(0x1001, self->poked);
1507 }
1508
1509 TEST_F(TRACE_poke, getpid_runs_normally)
1510 {
1511         long ret;
1512
1513         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1514         ASSERT_EQ(0, ret);
1515
1516         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1517         ASSERT_EQ(0, ret);
1518
1519         EXPECT_EQ(0, self->poked);
1520         EXPECT_NE(0, syscall(__NR_getpid));
1521         EXPECT_EQ(0, self->poked);
1522 }
1523
1524 #if defined(__x86_64__)
1525 # define ARCH_REGS      struct user_regs_struct
1526 # define SYSCALL_NUM    orig_rax
1527 # define SYSCALL_RET    rax
1528 #elif defined(__i386__)
1529 # define ARCH_REGS      struct user_regs_struct
1530 # define SYSCALL_NUM    orig_eax
1531 # define SYSCALL_RET    eax
1532 #elif defined(__arm__)
1533 # define ARCH_REGS      struct pt_regs
1534 # define SYSCALL_NUM    ARM_r7
1535 # define SYSCALL_RET    ARM_r0
1536 #elif defined(__aarch64__)
1537 # define ARCH_REGS      struct user_pt_regs
1538 # define SYSCALL_NUM    regs[8]
1539 # define SYSCALL_RET    regs[0]
1540 #elif defined(__hppa__)
1541 # define ARCH_REGS      struct user_regs_struct
1542 # define SYSCALL_NUM    gr[20]
1543 # define SYSCALL_RET    gr[28]
1544 #elif defined(__powerpc__)
1545 # define ARCH_REGS      struct pt_regs
1546 # define SYSCALL_NUM    gpr[0]
1547 # define SYSCALL_RET    gpr[3]
1548 #elif defined(__s390__)
1549 # define ARCH_REGS     s390_regs
1550 # define SYSCALL_NUM   gprs[2]
1551 # define SYSCALL_RET   gprs[2]
1552 #elif defined(__mips__)
1553 # define ARCH_REGS      struct pt_regs
1554 # define SYSCALL_NUM    regs[2]
1555 # define SYSCALL_SYSCALL_NUM regs[4]
1556 # define SYSCALL_RET    regs[2]
1557 # define SYSCALL_NUM_RET_SHARE_REG
1558 #else
1559 # error "Do not know how to find your architecture's registers and syscalls"
1560 #endif
1561
1562 /* When the syscall return can't be changed, stub out the tests for it. */
1563 #ifdef SYSCALL_NUM_RET_SHARE_REG
1564 # define EXPECT_SYSCALL_RETURN(val, action)     EXPECT_EQ(-1, action)
1565 #else
1566 # define EXPECT_SYSCALL_RETURN(val, action)     EXPECT_EQ(val, action)
1567 #endif
1568
1569 /* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1570  * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1571  */
1572 #if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
1573 #define HAVE_GETREGS
1574 #endif
1575
1576 /* Architecture-specific syscall fetching routine. */
1577 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1578 {
1579         ARCH_REGS regs;
1580 #ifdef HAVE_GETREGS
1581         EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
1582                 TH_LOG("PTRACE_GETREGS failed");
1583                 return -1;
1584         }
1585 #else
1586         struct iovec iov;
1587
1588         iov.iov_base = &regs;
1589         iov.iov_len = sizeof(regs);
1590         EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1591                 TH_LOG("PTRACE_GETREGSET failed");
1592                 return -1;
1593         }
1594 #endif
1595
1596 #if defined(__mips__)
1597         if (regs.SYSCALL_NUM == __NR_O32_Linux)
1598                 return regs.SYSCALL_SYSCALL_NUM;
1599 #endif
1600         return regs.SYSCALL_NUM;
1601 }
1602
1603 /* Architecture-specific syscall changing routine. */
1604 void change_syscall(struct __test_metadata *_metadata,
1605                     pid_t tracee, int syscall)
1606 {
1607         int ret;
1608         ARCH_REGS regs;
1609 #ifdef HAVE_GETREGS
1610         ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
1611 #else
1612         struct iovec iov;
1613         iov.iov_base = &regs;
1614         iov.iov_len = sizeof(regs);
1615         ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
1616 #endif
1617         EXPECT_EQ(0, ret) {}
1618
1619 #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
1620     defined(__s390__) || defined(__hppa__)
1621         {
1622                 regs.SYSCALL_NUM = syscall;
1623         }
1624 #elif defined(__mips__)
1625         {
1626                 if (regs.SYSCALL_NUM == __NR_O32_Linux)
1627                         regs.SYSCALL_SYSCALL_NUM = syscall;
1628                 else
1629                         regs.SYSCALL_NUM = syscall;
1630         }
1631
1632 #elif defined(__arm__)
1633 # ifndef PTRACE_SET_SYSCALL
1634 #  define PTRACE_SET_SYSCALL   23
1635 # endif
1636         {
1637                 ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
1638                 EXPECT_EQ(0, ret);
1639         }
1640
1641 #elif defined(__aarch64__)
1642 # ifndef NT_ARM_SYSTEM_CALL
1643 #  define NT_ARM_SYSTEM_CALL 0x404
1644 # endif
1645         {
1646                 iov.iov_base = &syscall;
1647                 iov.iov_len = sizeof(syscall);
1648                 ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
1649                              &iov);
1650                 EXPECT_EQ(0, ret);
1651         }
1652
1653 #else
1654         ASSERT_EQ(1, 0) {
1655                 TH_LOG("How is the syscall changed on this architecture?");
1656         }
1657 #endif
1658
1659         /* If syscall is skipped, change return value. */
1660         if (syscall == -1)
1661 #ifdef SYSCALL_NUM_RET_SHARE_REG
1662                 TH_LOG("Can't modify syscall return on this architecture");
1663 #else
1664                 regs.SYSCALL_RET = EPERM;
1665 #endif
1666
1667 #ifdef HAVE_GETREGS
1668         ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
1669 #else
1670         iov.iov_base = &regs;
1671         iov.iov_len = sizeof(regs);
1672         ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
1673 #endif
1674         EXPECT_EQ(0, ret);
1675 }
1676
1677 void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
1678                     int status, void *args)
1679 {
1680         int ret;
1681         unsigned long msg;
1682
1683         /* Make sure we got the right message. */
1684         ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1685         EXPECT_EQ(0, ret);
1686
1687         /* Validate and take action on expected syscalls. */
1688         switch (msg) {
1689         case 0x1002:
1690                 /* change getpid to getppid. */
1691                 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
1692                 change_syscall(_metadata, tracee, __NR_getppid);
1693                 break;
1694         case 0x1003:
1695                 /* skip gettid. */
1696                 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
1697                 change_syscall(_metadata, tracee, -1);
1698                 break;
1699         case 0x1004:
1700                 /* do nothing (allow getppid) */
1701                 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
1702                 break;
1703         default:
1704                 EXPECT_EQ(0, msg) {
1705                         TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1706                         kill(tracee, SIGKILL);
1707                 }
1708         }
1709
1710 }
1711
1712 void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
1713                    int status, void *args)
1714 {
1715         int ret, nr;
1716         unsigned long msg;
1717         static bool entry;
1718
1719         /* Make sure we got an empty message. */
1720         ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1721         EXPECT_EQ(0, ret);
1722         EXPECT_EQ(0, msg);
1723
1724         /* The only way to tell PTRACE_SYSCALL entry/exit is by counting. */
1725         entry = !entry;
1726         if (!entry)
1727                 return;
1728
1729         nr = get_syscall(_metadata, tracee);
1730
1731         if (nr == __NR_getpid)
1732                 change_syscall(_metadata, tracee, __NR_getppid);
1733         if (nr == __NR_openat)
1734                 change_syscall(_metadata, tracee, -1);
1735 }
1736
1737 FIXTURE_DATA(TRACE_syscall) {
1738         struct sock_fprog prog;
1739         pid_t tracer, mytid, mypid, parent;
1740 };
1741
1742 FIXTURE_SETUP(TRACE_syscall)
1743 {
1744         struct sock_filter filter[] = {
1745                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1746                         offsetof(struct seccomp_data, nr)),
1747                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1748                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1749                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1750                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
1751                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1752                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
1753                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1754         };
1755
1756         memset(&self->prog, 0, sizeof(self->prog));
1757         self->prog.filter = malloc(sizeof(filter));
1758         ASSERT_NE(NULL, self->prog.filter);
1759         memcpy(self->prog.filter, filter, sizeof(filter));
1760         self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1761
1762         /* Prepare some testable syscall results. */
1763         self->mytid = syscall(__NR_gettid);
1764         ASSERT_GT(self->mytid, 0);
1765         ASSERT_NE(self->mytid, 1) {
1766                 TH_LOG("Running this test as init is not supported. :)");
1767         }
1768
1769         self->mypid = getpid();
1770         ASSERT_GT(self->mypid, 0);
1771         ASSERT_EQ(self->mytid, self->mypid);
1772
1773         self->parent = getppid();
1774         ASSERT_GT(self->parent, 0);
1775         ASSERT_NE(self->parent, self->mypid);
1776
1777         /* Launch tracer. */
1778         self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL,
1779                                            false);
1780 }
1781
1782 FIXTURE_TEARDOWN(TRACE_syscall)
1783 {
1784         teardown_trace_fixture(_metadata, self->tracer);
1785         if (self->prog.filter)
1786                 free(self->prog.filter);
1787 }
1788
1789 TEST_F(TRACE_syscall, ptrace_syscall_redirected)
1790 {
1791         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1792         teardown_trace_fixture(_metadata, self->tracer);
1793         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1794                                            true);
1795
1796         /* Tracer will redirect getpid to getppid. */
1797         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1798 }
1799
1800 TEST_F(TRACE_syscall, ptrace_syscall_dropped)
1801 {
1802         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1803         teardown_trace_fixture(_metadata, self->tracer);
1804         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1805                                            true);
1806
1807         /* Tracer should skip the open syscall, resulting in EPERM. */
1808         EXPECT_SYSCALL_RETURN(EPERM, syscall(__NR_openat));
1809 }
1810
1811 TEST_F(TRACE_syscall, syscall_allowed)
1812 {
1813         long ret;
1814
1815         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1816         ASSERT_EQ(0, ret);
1817
1818         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1819         ASSERT_EQ(0, ret);
1820
1821         /* getppid works as expected (no changes). */
1822         EXPECT_EQ(self->parent, syscall(__NR_getppid));
1823         EXPECT_NE(self->mypid, syscall(__NR_getppid));
1824 }
1825
1826 TEST_F(TRACE_syscall, syscall_redirected)
1827 {
1828         long ret;
1829
1830         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1831         ASSERT_EQ(0, ret);
1832
1833         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1834         ASSERT_EQ(0, ret);
1835
1836         /* getpid has been redirected to getppid as expected. */
1837         EXPECT_EQ(self->parent, syscall(__NR_getpid));
1838         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1839 }
1840
1841 TEST_F(TRACE_syscall, syscall_dropped)
1842 {
1843         long ret;
1844
1845         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1846         ASSERT_EQ(0, ret);
1847
1848         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1849         ASSERT_EQ(0, ret);
1850
1851         /* gettid has been skipped and an altered return value stored. */
1852         EXPECT_SYSCALL_RETURN(EPERM, syscall(__NR_gettid));
1853         EXPECT_NE(self->mytid, syscall(__NR_gettid));
1854 }
1855
1856 TEST_F(TRACE_syscall, skip_after_RET_TRACE)
1857 {
1858         struct sock_filter filter[] = {
1859                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1860                         offsetof(struct seccomp_data, nr)),
1861                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1862                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1863                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1864         };
1865         struct sock_fprog prog = {
1866                 .len = (unsigned short)ARRAY_SIZE(filter),
1867                 .filter = filter,
1868         };
1869         long ret;
1870
1871         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1872         ASSERT_EQ(0, ret);
1873
1874         /* Install fixture filter. */
1875         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1876         ASSERT_EQ(0, ret);
1877
1878         /* Install "errno on getppid" filter. */
1879         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1880         ASSERT_EQ(0, ret);
1881
1882         /* Tracer will redirect getpid to getppid, and we should see EPERM. */
1883         errno = 0;
1884         EXPECT_EQ(-1, syscall(__NR_getpid));
1885         EXPECT_EQ(EPERM, errno);
1886 }
1887
1888 TEST_F_SIGNAL(TRACE_syscall, kill_after_RET_TRACE, SIGSYS)
1889 {
1890         struct sock_filter filter[] = {
1891                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1892                         offsetof(struct seccomp_data, nr)),
1893                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1894                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1895                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1896         };
1897         struct sock_fprog prog = {
1898                 .len = (unsigned short)ARRAY_SIZE(filter),
1899                 .filter = filter,
1900         };
1901         long ret;
1902
1903         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1904         ASSERT_EQ(0, ret);
1905
1906         /* Install fixture filter. */
1907         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1908         ASSERT_EQ(0, ret);
1909
1910         /* Install "death on getppid" filter. */
1911         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1912         ASSERT_EQ(0, ret);
1913
1914         /* Tracer will redirect getpid to getppid, and we should die. */
1915         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1916 }
1917
1918 TEST_F(TRACE_syscall, skip_after_ptrace)
1919 {
1920         struct sock_filter filter[] = {
1921                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1922                         offsetof(struct seccomp_data, nr)),
1923                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1924                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1925                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1926         };
1927         struct sock_fprog prog = {
1928                 .len = (unsigned short)ARRAY_SIZE(filter),
1929                 .filter = filter,
1930         };
1931         long ret;
1932
1933         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1934         teardown_trace_fixture(_metadata, self->tracer);
1935         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1936                                            true);
1937
1938         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1939         ASSERT_EQ(0, ret);
1940
1941         /* Install "errno on getppid" filter. */
1942         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1943         ASSERT_EQ(0, ret);
1944
1945         /* Tracer will redirect getpid to getppid, and we should see EPERM. */
1946         EXPECT_EQ(-1, syscall(__NR_getpid));
1947         EXPECT_EQ(EPERM, errno);
1948 }
1949
1950 TEST_F_SIGNAL(TRACE_syscall, kill_after_ptrace, SIGSYS)
1951 {
1952         struct sock_filter filter[] = {
1953                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1954                         offsetof(struct seccomp_data, nr)),
1955                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1956                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1957                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1958         };
1959         struct sock_fprog prog = {
1960                 .len = (unsigned short)ARRAY_SIZE(filter),
1961                 .filter = filter,
1962         };
1963         long ret;
1964
1965         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1966         teardown_trace_fixture(_metadata, self->tracer);
1967         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1968                                            true);
1969
1970         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1971         ASSERT_EQ(0, ret);
1972
1973         /* Install "death on getppid" filter. */
1974         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1975         ASSERT_EQ(0, ret);
1976
1977         /* Tracer will redirect getpid to getppid, and we should die. */
1978         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1979 }
1980
1981 TEST(seccomp_syscall)
1982 {
1983         struct sock_filter filter[] = {
1984                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1985         };
1986         struct sock_fprog prog = {
1987                 .len = (unsigned short)ARRAY_SIZE(filter),
1988                 .filter = filter,
1989         };
1990         long ret;
1991
1992         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1993         ASSERT_EQ(0, ret) {
1994                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
1995         }
1996
1997         /* Reject insane operation. */
1998         ret = seccomp(-1, 0, &prog);
1999         ASSERT_NE(ENOSYS, errno) {
2000                 TH_LOG("Kernel does not support seccomp syscall!");
2001         }
2002         EXPECT_EQ(EINVAL, errno) {
2003                 TH_LOG("Did not reject crazy op value!");
2004         }
2005
2006         /* Reject strict with flags or pointer. */
2007         ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
2008         EXPECT_EQ(EINVAL, errno) {
2009                 TH_LOG("Did not reject mode strict with flags!");
2010         }
2011         ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
2012         EXPECT_EQ(EINVAL, errno) {
2013                 TH_LOG("Did not reject mode strict with uargs!");
2014         }
2015
2016         /* Reject insane args for filter. */
2017         ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
2018         EXPECT_EQ(EINVAL, errno) {
2019                 TH_LOG("Did not reject crazy filter flags!");
2020         }
2021         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
2022         EXPECT_EQ(EFAULT, errno) {
2023                 TH_LOG("Did not reject NULL filter!");
2024         }
2025
2026         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2027         EXPECT_EQ(0, errno) {
2028                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
2029                         strerror(errno));
2030         }
2031 }
2032
2033 TEST(seccomp_syscall_mode_lock)
2034 {
2035         struct sock_filter filter[] = {
2036                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2037         };
2038         struct sock_fprog prog = {
2039                 .len = (unsigned short)ARRAY_SIZE(filter),
2040                 .filter = filter,
2041         };
2042         long ret;
2043
2044         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2045         ASSERT_EQ(0, ret) {
2046                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2047         }
2048
2049         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2050         ASSERT_NE(ENOSYS, errno) {
2051                 TH_LOG("Kernel does not support seccomp syscall!");
2052         }
2053         EXPECT_EQ(0, ret) {
2054                 TH_LOG("Could not install filter!");
2055         }
2056
2057         /* Make sure neither entry point will switch to strict. */
2058         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
2059         EXPECT_EQ(EINVAL, errno) {
2060                 TH_LOG("Switched to mode strict!");
2061         }
2062
2063         ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
2064         EXPECT_EQ(EINVAL, errno) {
2065                 TH_LOG("Switched to mode strict!");
2066         }
2067 }
2068
2069 /*
2070  * Test detection of known and unknown filter flags. Userspace needs to be able
2071  * to check if a filter flag is supported by the current kernel and a good way
2072  * of doing that is by attempting to enter filter mode, with the flag bit in
2073  * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
2074  * that the flag is valid and EINVAL indicates that the flag is invalid.
2075  */
2076 TEST(detect_seccomp_filter_flags)
2077 {
2078         unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
2079                                  SECCOMP_FILTER_FLAG_LOG,
2080                                  SECCOMP_FILTER_FLAG_SPEC_ALLOW };
2081         unsigned int flag, all_flags;
2082         int i;
2083         long ret;
2084
2085         /* Test detection of known-good filter flags */
2086         for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
2087                 int bits = 0;
2088
2089                 flag = flags[i];
2090                 /* Make sure the flag is a single bit! */
2091                 while (flag) {
2092                         if (flag & 0x1)
2093                                 bits ++;
2094                         flag >>= 1;
2095                 }
2096                 ASSERT_EQ(1, bits);
2097                 flag = flags[i];
2098
2099                 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2100                 ASSERT_NE(ENOSYS, errno) {
2101                         TH_LOG("Kernel does not support seccomp syscall!");
2102                 }
2103                 EXPECT_EQ(-1, ret);
2104                 EXPECT_EQ(EFAULT, errno) {
2105                         TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
2106                                flag);
2107                 }
2108
2109                 all_flags |= flag;
2110         }
2111
2112         /* Test detection of all known-good filter flags */
2113         ret = seccomp(SECCOMP_SET_MODE_FILTER, all_flags, NULL);
2114         EXPECT_EQ(-1, ret);
2115         EXPECT_EQ(EFAULT, errno) {
2116                 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
2117                        all_flags);
2118         }
2119
2120         /* Test detection of an unknown filter flag */
2121         flag = -1;
2122         ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2123         EXPECT_EQ(-1, ret);
2124         EXPECT_EQ(EINVAL, errno) {
2125                 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
2126                        flag);
2127         }
2128
2129         /*
2130          * Test detection of an unknown filter flag that may simply need to be
2131          * added to this test
2132          */
2133         flag = flags[ARRAY_SIZE(flags) - 1] << 1;
2134         ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2135         EXPECT_EQ(-1, ret);
2136         EXPECT_EQ(EINVAL, errno) {
2137                 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?",
2138                        flag);
2139         }
2140 }
2141
2142 TEST(TSYNC_first)
2143 {
2144         struct sock_filter filter[] = {
2145                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2146         };
2147         struct sock_fprog prog = {
2148                 .len = (unsigned short)ARRAY_SIZE(filter),
2149                 .filter = filter,
2150         };
2151         long ret;
2152
2153         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2154         ASSERT_EQ(0, ret) {
2155                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2156         }
2157
2158         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2159                       &prog);
2160         ASSERT_NE(ENOSYS, errno) {
2161                 TH_LOG("Kernel does not support seccomp syscall!");
2162         }
2163         EXPECT_EQ(0, ret) {
2164                 TH_LOG("Could not install initial filter with TSYNC!");
2165         }
2166 }
2167
2168 #define TSYNC_SIBLINGS 2
2169 struct tsync_sibling {
2170         pthread_t tid;
2171         pid_t system_tid;
2172         sem_t *started;
2173         pthread_cond_t *cond;
2174         pthread_mutex_t *mutex;
2175         int diverge;
2176         int num_waits;
2177         struct sock_fprog *prog;
2178         struct __test_metadata *metadata;
2179 };
2180
2181 /*
2182  * To avoid joining joined threads (which is not allowed by Bionic),
2183  * make sure we both successfully join and clear the tid to skip a
2184  * later join attempt during fixture teardown. Any remaining threads
2185  * will be directly killed during teardown.
2186  */
2187 #define PTHREAD_JOIN(tid, status)                                       \
2188         do {                                                            \
2189                 int _rc = pthread_join(tid, status);                    \
2190                 if (_rc) {                                              \
2191                         TH_LOG("pthread_join of tid %u failed: %d\n",   \
2192                                 (unsigned int)tid, _rc);                \
2193                 } else {                                                \
2194                         tid = 0;                                        \
2195                 }                                                       \
2196         } while (0)
2197
2198 FIXTURE_DATA(TSYNC) {
2199         struct sock_fprog root_prog, apply_prog;
2200         struct tsync_sibling sibling[TSYNC_SIBLINGS];
2201         sem_t started;
2202         pthread_cond_t cond;
2203         pthread_mutex_t mutex;
2204         int sibling_count;
2205 };
2206
2207 FIXTURE_SETUP(TSYNC)
2208 {
2209         struct sock_filter root_filter[] = {
2210                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2211         };
2212         struct sock_filter apply_filter[] = {
2213                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2214                         offsetof(struct seccomp_data, nr)),
2215                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
2216                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2217                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2218         };
2219
2220         memset(&self->root_prog, 0, sizeof(self->root_prog));
2221         memset(&self->apply_prog, 0, sizeof(self->apply_prog));
2222         memset(&self->sibling, 0, sizeof(self->sibling));
2223         self->root_prog.filter = malloc(sizeof(root_filter));
2224         ASSERT_NE(NULL, self->root_prog.filter);
2225         memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
2226         self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
2227
2228         self->apply_prog.filter = malloc(sizeof(apply_filter));
2229         ASSERT_NE(NULL, self->apply_prog.filter);
2230         memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
2231         self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
2232
2233         self->sibling_count = 0;
2234         pthread_mutex_init(&self->mutex, NULL);
2235         pthread_cond_init(&self->cond, NULL);
2236         sem_init(&self->started, 0, 0);
2237         self->sibling[0].tid = 0;
2238         self->sibling[0].cond = &self->cond;
2239         self->sibling[0].started = &self->started;
2240         self->sibling[0].mutex = &self->mutex;
2241         self->sibling[0].diverge = 0;
2242         self->sibling[0].num_waits = 1;
2243         self->sibling[0].prog = &self->root_prog;
2244         self->sibling[0].metadata = _metadata;
2245         self->sibling[1].tid = 0;
2246         self->sibling[1].cond = &self->cond;
2247         self->sibling[1].started = &self->started;
2248         self->sibling[1].mutex = &self->mutex;
2249         self->sibling[1].diverge = 0;
2250         self->sibling[1].prog = &self->root_prog;
2251         self->sibling[1].num_waits = 1;
2252         self->sibling[1].metadata = _metadata;
2253 }
2254
2255 FIXTURE_TEARDOWN(TSYNC)
2256 {
2257         int sib = 0;
2258
2259         if (self->root_prog.filter)
2260                 free(self->root_prog.filter);
2261         if (self->apply_prog.filter)
2262                 free(self->apply_prog.filter);
2263
2264         for ( ; sib < self->sibling_count; ++sib) {
2265                 struct tsync_sibling *s = &self->sibling[sib];
2266
2267                 if (!s->tid)
2268                         continue;
2269                 /*
2270                  * If a thread is still running, it may be stuck, so hit
2271                  * it over the head really hard.
2272                  */
2273                 pthread_kill(s->tid, 9);
2274         }
2275         pthread_mutex_destroy(&self->mutex);
2276         pthread_cond_destroy(&self->cond);
2277         sem_destroy(&self->started);
2278 }
2279
2280 void *tsync_sibling(void *data)
2281 {
2282         long ret = 0;
2283         struct tsync_sibling *me = data;
2284
2285         me->system_tid = syscall(__NR_gettid);
2286
2287         pthread_mutex_lock(me->mutex);
2288         if (me->diverge) {
2289                 /* Just re-apply the root prog to fork the tree */
2290                 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
2291                                 me->prog, 0, 0);
2292         }
2293         sem_post(me->started);
2294         /* Return outside of started so parent notices failures. */
2295         if (ret) {
2296                 pthread_mutex_unlock(me->mutex);
2297                 return (void *)SIBLING_EXIT_FAILURE;
2298         }
2299         do {
2300                 pthread_cond_wait(me->cond, me->mutex);
2301                 me->num_waits = me->num_waits - 1;
2302         } while (me->num_waits);
2303         pthread_mutex_unlock(me->mutex);
2304
2305         ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
2306         if (!ret)
2307                 return (void *)SIBLING_EXIT_NEWPRIVS;
2308         read(0, NULL, 0);
2309         return (void *)SIBLING_EXIT_UNKILLED;
2310 }
2311
2312 void tsync_start_sibling(struct tsync_sibling *sibling)
2313 {
2314         pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
2315 }
2316
2317 TEST_F(TSYNC, siblings_fail_prctl)
2318 {
2319         long ret;
2320         void *status;
2321         struct sock_filter filter[] = {
2322                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2323                         offsetof(struct seccomp_data, nr)),
2324                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
2325                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
2326                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2327         };
2328         struct sock_fprog prog = {
2329                 .len = (unsigned short)ARRAY_SIZE(filter),
2330                 .filter = filter,
2331         };
2332
2333         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2334                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2335         }
2336
2337         /* Check prctl failure detection by requesting sib 0 diverge. */
2338         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2339         ASSERT_NE(ENOSYS, errno) {
2340                 TH_LOG("Kernel does not support seccomp syscall!");
2341         }
2342         ASSERT_EQ(0, ret) {
2343                 TH_LOG("setting filter failed");
2344         }
2345
2346         self->sibling[0].diverge = 1;
2347         tsync_start_sibling(&self->sibling[0]);
2348         tsync_start_sibling(&self->sibling[1]);
2349
2350         while (self->sibling_count < TSYNC_SIBLINGS) {
2351                 sem_wait(&self->started);
2352                 self->sibling_count++;
2353         }
2354
2355         /* Signal the threads to clean up*/
2356         pthread_mutex_lock(&self->mutex);
2357         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2358                 TH_LOG("cond broadcast non-zero");
2359         }
2360         pthread_mutex_unlock(&self->mutex);
2361
2362         /* Ensure diverging sibling failed to call prctl. */
2363         PTHREAD_JOIN(self->sibling[0].tid, &status);
2364         EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
2365         PTHREAD_JOIN(self->sibling[1].tid, &status);
2366         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2367 }
2368
2369 TEST_F(TSYNC, two_siblings_with_ancestor)
2370 {
2371         long ret;
2372         void *status;
2373
2374         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2375                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2376         }
2377
2378         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2379         ASSERT_NE(ENOSYS, errno) {
2380                 TH_LOG("Kernel does not support seccomp syscall!");
2381         }
2382         ASSERT_EQ(0, ret) {
2383                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2384         }
2385         tsync_start_sibling(&self->sibling[0]);
2386         tsync_start_sibling(&self->sibling[1]);
2387
2388         while (self->sibling_count < TSYNC_SIBLINGS) {
2389                 sem_wait(&self->started);
2390                 self->sibling_count++;
2391         }
2392
2393         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2394                       &self->apply_prog);
2395         ASSERT_EQ(0, ret) {
2396                 TH_LOG("Could install filter on all threads!");
2397         }
2398         /* Tell the siblings to test the policy */
2399         pthread_mutex_lock(&self->mutex);
2400         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2401                 TH_LOG("cond broadcast non-zero");
2402         }
2403         pthread_mutex_unlock(&self->mutex);
2404         /* Ensure they are both killed and don't exit cleanly. */
2405         PTHREAD_JOIN(self->sibling[0].tid, &status);
2406         EXPECT_EQ(0x0, (long)status);
2407         PTHREAD_JOIN(self->sibling[1].tid, &status);
2408         EXPECT_EQ(0x0, (long)status);
2409 }
2410
2411 TEST_F(TSYNC, two_sibling_want_nnp)
2412 {
2413         void *status;
2414
2415         /* start siblings before any prctl() operations */
2416         tsync_start_sibling(&self->sibling[0]);
2417         tsync_start_sibling(&self->sibling[1]);
2418         while (self->sibling_count < TSYNC_SIBLINGS) {
2419                 sem_wait(&self->started);
2420                 self->sibling_count++;
2421         }
2422
2423         /* Tell the siblings to test no policy */
2424         pthread_mutex_lock(&self->mutex);
2425         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2426                 TH_LOG("cond broadcast non-zero");
2427         }
2428         pthread_mutex_unlock(&self->mutex);
2429
2430         /* Ensure they are both upset about lacking nnp. */
2431         PTHREAD_JOIN(self->sibling[0].tid, &status);
2432         EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2433         PTHREAD_JOIN(self->sibling[1].tid, &status);
2434         EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2435 }
2436
2437 TEST_F(TSYNC, two_siblings_with_no_filter)
2438 {
2439         long ret;
2440         void *status;
2441
2442         /* start siblings before any prctl() operations */
2443         tsync_start_sibling(&self->sibling[0]);
2444         tsync_start_sibling(&self->sibling[1]);
2445         while (self->sibling_count < TSYNC_SIBLINGS) {
2446                 sem_wait(&self->started);
2447                 self->sibling_count++;
2448         }
2449
2450         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2451                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2452         }
2453
2454         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2455                       &self->apply_prog);
2456         ASSERT_NE(ENOSYS, errno) {
2457                 TH_LOG("Kernel does not support seccomp syscall!");
2458         }
2459         ASSERT_EQ(0, ret) {
2460                 TH_LOG("Could install filter on all threads!");
2461         }
2462
2463         /* Tell the siblings to test the policy */
2464         pthread_mutex_lock(&self->mutex);
2465         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2466                 TH_LOG("cond broadcast non-zero");
2467         }
2468         pthread_mutex_unlock(&self->mutex);
2469
2470         /* Ensure they are both killed and don't exit cleanly. */
2471         PTHREAD_JOIN(self->sibling[0].tid, &status);
2472         EXPECT_EQ(0x0, (long)status);
2473         PTHREAD_JOIN(self->sibling[1].tid, &status);
2474         EXPECT_EQ(0x0, (long)status);
2475 }
2476
2477 TEST_F(TSYNC, two_siblings_with_one_divergence)
2478 {
2479         long ret;
2480         void *status;
2481
2482         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2483                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2484         }
2485
2486         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2487         ASSERT_NE(ENOSYS, errno) {
2488                 TH_LOG("Kernel does not support seccomp syscall!");
2489         }
2490         ASSERT_EQ(0, ret) {
2491                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2492         }
2493         self->sibling[0].diverge = 1;
2494         tsync_start_sibling(&self->sibling[0]);
2495         tsync_start_sibling(&self->sibling[1]);
2496
2497         while (self->sibling_count < TSYNC_SIBLINGS) {
2498                 sem_wait(&self->started);
2499                 self->sibling_count++;
2500         }
2501
2502         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2503                       &self->apply_prog);
2504         ASSERT_EQ(self->sibling[0].system_tid, ret) {
2505                 TH_LOG("Did not fail on diverged sibling.");
2506         }
2507
2508         /* Wake the threads */
2509         pthread_mutex_lock(&self->mutex);
2510         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2511                 TH_LOG("cond broadcast non-zero");
2512         }
2513         pthread_mutex_unlock(&self->mutex);
2514
2515         /* Ensure they are both unkilled. */
2516         PTHREAD_JOIN(self->sibling[0].tid, &status);
2517         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2518         PTHREAD_JOIN(self->sibling[1].tid, &status);
2519         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2520 }
2521
2522 TEST_F(TSYNC, two_siblings_not_under_filter)
2523 {
2524         long ret, sib;
2525         void *status;
2526
2527         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2528                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2529         }
2530
2531         /*
2532          * Sibling 0 will have its own seccomp policy
2533          * and Sibling 1 will not be under seccomp at
2534          * all. Sibling 1 will enter seccomp and 0
2535          * will cause failure.
2536          */
2537         self->sibling[0].diverge = 1;
2538         tsync_start_sibling(&self->sibling[0]);
2539         tsync_start_sibling(&self->sibling[1]);
2540
2541         while (self->sibling_count < TSYNC_SIBLINGS) {
2542                 sem_wait(&self->started);
2543                 self->sibling_count++;
2544         }
2545
2546         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2547         ASSERT_NE(ENOSYS, errno) {
2548                 TH_LOG("Kernel does not support seccomp syscall!");
2549         }
2550         ASSERT_EQ(0, ret) {
2551                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2552         }
2553
2554         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2555                       &self->apply_prog);
2556         ASSERT_EQ(ret, self->sibling[0].system_tid) {
2557                 TH_LOG("Did not fail on diverged sibling.");
2558         }
2559         sib = 1;
2560         if (ret == self->sibling[0].system_tid)
2561                 sib = 0;
2562
2563         pthread_mutex_lock(&self->mutex);
2564
2565         /* Increment the other siblings num_waits so we can clean up
2566          * the one we just saw.
2567          */
2568         self->sibling[!sib].num_waits += 1;
2569
2570         /* Signal the thread to clean up*/
2571         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2572                 TH_LOG("cond broadcast non-zero");
2573         }
2574         pthread_mutex_unlock(&self->mutex);
2575         PTHREAD_JOIN(self->sibling[sib].tid, &status);
2576         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2577         /* Poll for actual task death. pthread_join doesn't guarantee it. */
2578         while (!kill(self->sibling[sib].system_tid, 0))
2579                 sleep(0.1);
2580         /* Switch to the remaining sibling */
2581         sib = !sib;
2582
2583         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2584                       &self->apply_prog);
2585         ASSERT_EQ(0, ret) {
2586                 TH_LOG("Expected the remaining sibling to sync");
2587         };
2588
2589         pthread_mutex_lock(&self->mutex);
2590
2591         /* If remaining sibling didn't have a chance to wake up during
2592          * the first broadcast, manually reduce the num_waits now.
2593          */
2594         if (self->sibling[sib].num_waits > 1)
2595                 self->sibling[sib].num_waits = 1;
2596         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2597                 TH_LOG("cond broadcast non-zero");
2598         }
2599         pthread_mutex_unlock(&self->mutex);
2600         PTHREAD_JOIN(self->sibling[sib].tid, &status);
2601         EXPECT_EQ(0, (long)status);
2602         /* Poll for actual task death. pthread_join doesn't guarantee it. */
2603         while (!kill(self->sibling[sib].system_tid, 0))
2604                 sleep(0.1);
2605
2606         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2607                       &self->apply_prog);
2608         ASSERT_EQ(0, ret);  /* just us chickens */
2609 }
2610
2611 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
2612 TEST(syscall_restart)
2613 {
2614         long ret;
2615         unsigned long msg;
2616         pid_t child_pid;
2617         int pipefd[2];
2618         int status;
2619         siginfo_t info = { };
2620         struct sock_filter filter[] = {
2621                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2622                          offsetof(struct seccomp_data, nr)),
2623
2624 #ifdef __NR_sigreturn
2625                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0),
2626 #endif
2627                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
2628                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
2629                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
2630                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0),
2631                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2632
2633                 /* Allow __NR_write for easy logging. */
2634                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2635                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2636                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2637                 /* The nanosleep jump target. */
2638                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2639                 /* The restart_syscall jump target. */
2640                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
2641         };
2642         struct sock_fprog prog = {
2643                 .len = (unsigned short)ARRAY_SIZE(filter),
2644                 .filter = filter,
2645         };
2646 #if defined(__arm__)
2647         struct utsname utsbuf;
2648 #endif
2649
2650         ASSERT_EQ(0, pipe(pipefd));
2651
2652         child_pid = fork();
2653         ASSERT_LE(0, child_pid);
2654         if (child_pid == 0) {
2655                 /* Child uses EXPECT not ASSERT to deliver status correctly. */
2656                 char buf = ' ';
2657                 struct timespec timeout = { };
2658
2659                 /* Attach parent as tracer and stop. */
2660                 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2661                 EXPECT_EQ(0, raise(SIGSTOP));
2662
2663                 EXPECT_EQ(0, close(pipefd[1]));
2664
2665                 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2666                         TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2667                 }
2668
2669                 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2670                 EXPECT_EQ(0, ret) {
2671                         TH_LOG("Failed to install filter!");
2672                 }
2673
2674                 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2675                         TH_LOG("Failed to read() sync from parent");
2676                 }
2677                 EXPECT_EQ('.', buf) {
2678                         TH_LOG("Failed to get sync data from read()");
2679                 }
2680
2681                 /* Start nanosleep to be interrupted. */
2682                 timeout.tv_sec = 1;
2683                 errno = 0;
2684                 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2685                         TH_LOG("Call to nanosleep() failed (errno %d)", errno);
2686                 }
2687
2688                 /* Read final sync from parent. */
2689                 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2690                         TH_LOG("Failed final read() from parent");
2691                 }
2692                 EXPECT_EQ('!', buf) {
2693                         TH_LOG("Failed to get final data from read()");
2694                 }
2695
2696                 /* Directly report the status of our test harness results. */
2697                 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2698                                                      : EXIT_FAILURE);
2699         }
2700         EXPECT_EQ(0, close(pipefd[0]));
2701
2702         /* Attach to child, setup options, and release. */
2703         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2704         ASSERT_EQ(true, WIFSTOPPED(status));
2705         ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2706                             PTRACE_O_TRACESECCOMP));
2707         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2708         ASSERT_EQ(1, write(pipefd[1], ".", 1));
2709
2710         /* Wait for nanosleep() to start. */
2711         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2712         ASSERT_EQ(true, WIFSTOPPED(status));
2713         ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2714         ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2715         ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2716         ASSERT_EQ(0x100, msg);
2717         EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
2718
2719         /* Might as well check siginfo for sanity while we're here. */
2720         ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2721         ASSERT_EQ(SIGTRAP, info.si_signo);
2722         ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2723         EXPECT_EQ(0, info.si_errno);
2724         EXPECT_EQ(getuid(), info.si_uid);
2725         /* Verify signal delivery came from child (seccomp-triggered). */
2726         EXPECT_EQ(child_pid, info.si_pid);
2727
2728         /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
2729         ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2730         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2731         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2732         ASSERT_EQ(true, WIFSTOPPED(status));
2733         ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
2734         ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2735         /*
2736          * There is no siginfo on SIGSTOP any more, so we can't verify
2737          * signal delivery came from parent now (getpid() == info.si_pid).
2738          * https://lkml.kernel.org/r/CAGXu5jJaZAOzP1qFz66tYrtbuywqb+UN2SOA1VLHpCCOiYvYeg@mail.gmail.com
2739          * At least verify the SIGSTOP via PTRACE_GETSIGINFO.
2740          */
2741         EXPECT_EQ(SIGSTOP, info.si_signo);
2742
2743         /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
2744         ASSERT_EQ(0, kill(child_pid, SIGCONT));
2745         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2746         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2747         ASSERT_EQ(true, WIFSTOPPED(status));
2748         ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2749         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2750
2751         /* Wait for restart_syscall() to start. */
2752         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2753         ASSERT_EQ(true, WIFSTOPPED(status));
2754         ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2755         ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2756         ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2757
2758         ASSERT_EQ(0x200, msg);
2759         ret = get_syscall(_metadata, child_pid);
2760 #if defined(__arm__)
2761         /*
2762          * FIXME:
2763          * - native ARM registers do NOT expose true syscall.
2764          * - compat ARM registers on ARM64 DO expose true syscall.
2765          */
2766         ASSERT_EQ(0, uname(&utsbuf));
2767         if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2768                 EXPECT_EQ(__NR_nanosleep, ret);
2769         } else
2770 #endif
2771         {
2772                 EXPECT_EQ(__NR_restart_syscall, ret);
2773         }
2774
2775         /* Write again to end test. */
2776         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2777         ASSERT_EQ(1, write(pipefd[1], "!", 1));
2778         EXPECT_EQ(0, close(pipefd[1]));
2779
2780         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2781         if (WIFSIGNALED(status) || WEXITSTATUS(status))
2782                 _metadata->passed = 0;
2783 }
2784
2785 TEST_SIGNAL(filter_flag_log, SIGSYS)
2786 {
2787         struct sock_filter allow_filter[] = {
2788                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2789         };
2790         struct sock_filter kill_filter[] = {
2791                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2792                         offsetof(struct seccomp_data, nr)),
2793                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
2794                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2795                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2796         };
2797         struct sock_fprog allow_prog = {
2798                 .len = (unsigned short)ARRAY_SIZE(allow_filter),
2799                 .filter = allow_filter,
2800         };
2801         struct sock_fprog kill_prog = {
2802                 .len = (unsigned short)ARRAY_SIZE(kill_filter),
2803                 .filter = kill_filter,
2804         };
2805         long ret;
2806         pid_t parent = getppid();
2807
2808         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2809         ASSERT_EQ(0, ret);
2810
2811         /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
2812         ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
2813                       &allow_prog);
2814         ASSERT_NE(ENOSYS, errno) {
2815                 TH_LOG("Kernel does not support seccomp syscall!");
2816         }
2817         EXPECT_NE(0, ret) {
2818                 TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
2819         }
2820         EXPECT_EQ(EINVAL, errno) {
2821                 TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
2822         }
2823
2824         /* Verify that a simple, permissive filter can be added with no flags */
2825         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
2826         EXPECT_EQ(0, ret);
2827
2828         /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
2829         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2830                       &allow_prog);
2831         ASSERT_NE(EINVAL, errno) {
2832                 TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
2833         }
2834         EXPECT_EQ(0, ret);
2835
2836         /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
2837         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2838                       &kill_prog);
2839         EXPECT_EQ(0, ret);
2840
2841         EXPECT_EQ(parent, syscall(__NR_getppid));
2842         /* getpid() should never return. */
2843         EXPECT_EQ(0, syscall(__NR_getpid));
2844 }
2845
2846 TEST(get_action_avail)
2847 {
2848         __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
2849                             SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
2850                             SECCOMP_RET_LOG,   SECCOMP_RET_ALLOW };
2851         __u32 unknown_action = 0x10000000U;
2852         int i;
2853         long ret;
2854
2855         ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
2856         ASSERT_NE(ENOSYS, errno) {
2857                 TH_LOG("Kernel does not support seccomp syscall!");
2858         }
2859         ASSERT_NE(EINVAL, errno) {
2860                 TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
2861         }
2862         EXPECT_EQ(ret, 0);
2863
2864         for (i = 0; i < ARRAY_SIZE(actions); i++) {
2865                 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
2866                 EXPECT_EQ(ret, 0) {
2867                         TH_LOG("Expected action (0x%X) not available!",
2868                                actions[i]);
2869                 }
2870         }
2871
2872         /* Check that an unknown action is handled properly (EOPNOTSUPP) */
2873         ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
2874         EXPECT_EQ(ret, -1);
2875         EXPECT_EQ(errno, EOPNOTSUPP);
2876 }
2877
2878 TEST(get_metadata)
2879 {
2880         pid_t pid;
2881         int pipefd[2];
2882         char buf;
2883         struct seccomp_metadata md;
2884         long ret;
2885
2886         ASSERT_EQ(0, pipe(pipefd));
2887
2888         pid = fork();
2889         ASSERT_GE(pid, 0);
2890         if (pid == 0) {
2891                 struct sock_filter filter[] = {
2892                         BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2893                 };
2894                 struct sock_fprog prog = {
2895                         .len = (unsigned short)ARRAY_SIZE(filter),
2896                         .filter = filter,
2897                 };
2898
2899                 /* one with log, one without */
2900                 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
2901                                      SECCOMP_FILTER_FLAG_LOG, &prog));
2902                 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));
2903
2904                 ASSERT_EQ(0, close(pipefd[0]));
2905                 ASSERT_EQ(1, write(pipefd[1], "1", 1));
2906                 ASSERT_EQ(0, close(pipefd[1]));
2907
2908                 while (1)
2909                         sleep(100);
2910         }
2911
2912         ASSERT_EQ(0, close(pipefd[1]));
2913         ASSERT_EQ(1, read(pipefd[0], &buf, 1));
2914
2915         ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
2916         ASSERT_EQ(pid, waitpid(pid, NULL, 0));
2917
2918         /* Past here must not use ASSERT or child process is never killed. */
2919
2920         md.filter_off = 0;
2921         errno = 0;
2922         ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
2923         EXPECT_EQ(sizeof(md), ret) {
2924                 if (errno == EINVAL)
2925                         XFAIL(goto skip, "Kernel does not support PTRACE_SECCOMP_GET_METADATA (missing CONFIG_CHECKPOINT_RESTORE?)");
2926         }
2927
2928         EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
2929         EXPECT_EQ(md.filter_off, 0);
2930
2931         md.filter_off = 1;
2932         ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
2933         EXPECT_EQ(sizeof(md), ret);
2934         EXPECT_EQ(md.flags, 0);
2935         EXPECT_EQ(md.filter_off, 1);
2936
2937 skip:
2938         ASSERT_EQ(0, kill(pid, SIGKILL));
2939 }
2940
2941 /*
2942  * TODO:
2943  * - add microbenchmarks
2944  * - expand NNP testing
2945  * - better arch-specific TRACE and TRAP handlers.
2946  * - endianness checking when appropriate
2947  * - 64-bit arg prodding
2948  * - arch value testing (x86 modes especially)
2949  * - verify that FILTER_FLAG_LOG filters generate log messages
2950  * - verify that RET_LOG generates log messages
2951  * - ...
2952  */
2953
2954 TEST_HARNESS_MAIN