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)             \
1567         do {                                            \
1568                 errno = 0;                              \
1569                 if (val < 0) {                          \
1570                         EXPECT_EQ(-1, action);          \
1571                         EXPECT_EQ(-(val), errno);       \
1572                 } else {                                \
1573                         EXPECT_EQ(val, action);         \
1574                 }                                       \
1575         } while (0)
1576 #endif
1577
1578 /* Use PTRACE_GETREGS and PTRACE_SETREGS when available. This is useful for
1579  * architectures without HAVE_ARCH_TRACEHOOK (e.g. User-mode Linux).
1580  */
1581 #if defined(__x86_64__) || defined(__i386__) || defined(__mips__)
1582 #define HAVE_GETREGS
1583 #endif
1584
1585 /* Architecture-specific syscall fetching routine. */
1586 int get_syscall(struct __test_metadata *_metadata, pid_t tracee)
1587 {
1588         ARCH_REGS regs;
1589 #ifdef HAVE_GETREGS
1590         EXPECT_EQ(0, ptrace(PTRACE_GETREGS, tracee, 0, &regs)) {
1591                 TH_LOG("PTRACE_GETREGS failed");
1592                 return -1;
1593         }
1594 #else
1595         struct iovec iov;
1596
1597         iov.iov_base = &regs;
1598         iov.iov_len = sizeof(regs);
1599         EXPECT_EQ(0, ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov)) {
1600                 TH_LOG("PTRACE_GETREGSET failed");
1601                 return -1;
1602         }
1603 #endif
1604
1605 #if defined(__mips__)
1606         if (regs.SYSCALL_NUM == __NR_O32_Linux)
1607                 return regs.SYSCALL_SYSCALL_NUM;
1608 #endif
1609         return regs.SYSCALL_NUM;
1610 }
1611
1612 /* Architecture-specific syscall changing routine. */
1613 void change_syscall(struct __test_metadata *_metadata,
1614                     pid_t tracee, int syscall, int result)
1615 {
1616         int ret;
1617         ARCH_REGS regs;
1618 #ifdef HAVE_GETREGS
1619         ret = ptrace(PTRACE_GETREGS, tracee, 0, &regs);
1620 #else
1621         struct iovec iov;
1622         iov.iov_base = &regs;
1623         iov.iov_len = sizeof(regs);
1624         ret = ptrace(PTRACE_GETREGSET, tracee, NT_PRSTATUS, &iov);
1625 #endif
1626         EXPECT_EQ(0, ret) {}
1627
1628 #if defined(__x86_64__) || defined(__i386__) || defined(__powerpc__) || \
1629     defined(__s390__) || defined(__hppa__)
1630         {
1631                 regs.SYSCALL_NUM = syscall;
1632         }
1633 #elif defined(__mips__)
1634         {
1635                 if (regs.SYSCALL_NUM == __NR_O32_Linux)
1636                         regs.SYSCALL_SYSCALL_NUM = syscall;
1637                 else
1638                         regs.SYSCALL_NUM = syscall;
1639         }
1640
1641 #elif defined(__arm__)
1642 # ifndef PTRACE_SET_SYSCALL
1643 #  define PTRACE_SET_SYSCALL   23
1644 # endif
1645         {
1646                 ret = ptrace(PTRACE_SET_SYSCALL, tracee, NULL, syscall);
1647                 EXPECT_EQ(0, ret);
1648         }
1649
1650 #elif defined(__aarch64__)
1651 # ifndef NT_ARM_SYSTEM_CALL
1652 #  define NT_ARM_SYSTEM_CALL 0x404
1653 # endif
1654         {
1655                 iov.iov_base = &syscall;
1656                 iov.iov_len = sizeof(syscall);
1657                 ret = ptrace(PTRACE_SETREGSET, tracee, NT_ARM_SYSTEM_CALL,
1658                              &iov);
1659                 EXPECT_EQ(0, ret);
1660         }
1661
1662 #else
1663         ASSERT_EQ(1, 0) {
1664                 TH_LOG("How is the syscall changed on this architecture?");
1665         }
1666 #endif
1667
1668         /* If syscall is skipped, change return value. */
1669         if (syscall == -1)
1670 #ifdef SYSCALL_NUM_RET_SHARE_REG
1671                 TH_LOG("Can't modify syscall return on this architecture");
1672 #else
1673                 regs.SYSCALL_RET = result;
1674 #endif
1675
1676 #ifdef HAVE_GETREGS
1677         ret = ptrace(PTRACE_SETREGS, tracee, 0, &regs);
1678 #else
1679         iov.iov_base = &regs;
1680         iov.iov_len = sizeof(regs);
1681         ret = ptrace(PTRACE_SETREGSET, tracee, NT_PRSTATUS, &iov);
1682 #endif
1683         EXPECT_EQ(0, ret);
1684 }
1685
1686 void tracer_syscall(struct __test_metadata *_metadata, pid_t tracee,
1687                     int status, void *args)
1688 {
1689         int ret;
1690         unsigned long msg;
1691
1692         /* Make sure we got the right message. */
1693         ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1694         EXPECT_EQ(0, ret);
1695
1696         /* Validate and take action on expected syscalls. */
1697         switch (msg) {
1698         case 0x1002:
1699                 /* change getpid to getppid. */
1700                 EXPECT_EQ(__NR_getpid, get_syscall(_metadata, tracee));
1701                 change_syscall(_metadata, tracee, __NR_getppid, 0);
1702                 break;
1703         case 0x1003:
1704                 /* skip gettid with valid return code. */
1705                 EXPECT_EQ(__NR_gettid, get_syscall(_metadata, tracee));
1706                 change_syscall(_metadata, tracee, -1, 45000);
1707                 break;
1708         case 0x1004:
1709                 /* skip openat with error. */
1710                 EXPECT_EQ(__NR_openat, get_syscall(_metadata, tracee));
1711                 change_syscall(_metadata, tracee, -1, -ESRCH);
1712                 break;
1713         case 0x1005:
1714                 /* do nothing (allow getppid) */
1715                 EXPECT_EQ(__NR_getppid, get_syscall(_metadata, tracee));
1716                 break;
1717         default:
1718                 EXPECT_EQ(0, msg) {
1719                         TH_LOG("Unknown PTRACE_GETEVENTMSG: 0x%lx", msg);
1720                         kill(tracee, SIGKILL);
1721                 }
1722         }
1723
1724 }
1725
1726 void tracer_ptrace(struct __test_metadata *_metadata, pid_t tracee,
1727                    int status, void *args)
1728 {
1729         int ret, nr;
1730         unsigned long msg;
1731         static bool entry;
1732
1733         /* Make sure we got an empty message. */
1734         ret = ptrace(PTRACE_GETEVENTMSG, tracee, NULL, &msg);
1735         EXPECT_EQ(0, ret);
1736         EXPECT_EQ(0, msg);
1737
1738         /* The only way to tell PTRACE_SYSCALL entry/exit is by counting. */
1739         entry = !entry;
1740         if (!entry)
1741                 return;
1742
1743         nr = get_syscall(_metadata, tracee);
1744
1745         if (nr == __NR_getpid)
1746                 change_syscall(_metadata, tracee, __NR_getppid, 0);
1747         if (nr == __NR_gettid)
1748                 change_syscall(_metadata, tracee, -1, 45000);
1749         if (nr == __NR_openat)
1750                 change_syscall(_metadata, tracee, -1, -ESRCH);
1751 }
1752
1753 FIXTURE_DATA(TRACE_syscall) {
1754         struct sock_fprog prog;
1755         pid_t tracer, mytid, mypid, parent;
1756 };
1757
1758 FIXTURE_SETUP(TRACE_syscall)
1759 {
1760         struct sock_filter filter[] = {
1761                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1762                         offsetof(struct seccomp_data, nr)),
1763                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
1764                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1002),
1765                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_gettid, 0, 1),
1766                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1003),
1767                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_openat, 0, 1),
1768                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1004),
1769                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1770                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE | 0x1005),
1771                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1772         };
1773
1774         memset(&self->prog, 0, sizeof(self->prog));
1775         self->prog.filter = malloc(sizeof(filter));
1776         ASSERT_NE(NULL, self->prog.filter);
1777         memcpy(self->prog.filter, filter, sizeof(filter));
1778         self->prog.len = (unsigned short)ARRAY_SIZE(filter);
1779
1780         /* Prepare some testable syscall results. */
1781         self->mytid = syscall(__NR_gettid);
1782         ASSERT_GT(self->mytid, 0);
1783         ASSERT_NE(self->mytid, 1) {
1784                 TH_LOG("Running this test as init is not supported. :)");
1785         }
1786
1787         self->mypid = getpid();
1788         ASSERT_GT(self->mypid, 0);
1789         ASSERT_EQ(self->mytid, self->mypid);
1790
1791         self->parent = getppid();
1792         ASSERT_GT(self->parent, 0);
1793         ASSERT_NE(self->parent, self->mypid);
1794
1795         /* Launch tracer. */
1796         self->tracer = setup_trace_fixture(_metadata, tracer_syscall, NULL,
1797                                            false);
1798 }
1799
1800 FIXTURE_TEARDOWN(TRACE_syscall)
1801 {
1802         teardown_trace_fixture(_metadata, self->tracer);
1803         if (self->prog.filter)
1804                 free(self->prog.filter);
1805 }
1806
1807 TEST_F(TRACE_syscall, ptrace_syscall_redirected)
1808 {
1809         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1810         teardown_trace_fixture(_metadata, self->tracer);
1811         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1812                                            true);
1813
1814         /* Tracer will redirect getpid to getppid. */
1815         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1816 }
1817
1818 TEST_F(TRACE_syscall, ptrace_syscall_errno)
1819 {
1820         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1821         teardown_trace_fixture(_metadata, self->tracer);
1822         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1823                                            true);
1824
1825         /* Tracer should skip the open syscall, resulting in ESRCH. */
1826         EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
1827 }
1828
1829 TEST_F(TRACE_syscall, ptrace_syscall_faked)
1830 {
1831         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1832         teardown_trace_fixture(_metadata, self->tracer);
1833         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1834                                            true);
1835
1836         /* Tracer should skip the gettid syscall, resulting fake pid. */
1837         EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
1838 }
1839
1840 TEST_F(TRACE_syscall, syscall_allowed)
1841 {
1842         long ret;
1843
1844         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1845         ASSERT_EQ(0, ret);
1846
1847         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1848         ASSERT_EQ(0, ret);
1849
1850         /* getppid works as expected (no changes). */
1851         EXPECT_EQ(self->parent, syscall(__NR_getppid));
1852         EXPECT_NE(self->mypid, syscall(__NR_getppid));
1853 }
1854
1855 TEST_F(TRACE_syscall, syscall_redirected)
1856 {
1857         long ret;
1858
1859         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1860         ASSERT_EQ(0, ret);
1861
1862         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1863         ASSERT_EQ(0, ret);
1864
1865         /* getpid has been redirected to getppid as expected. */
1866         EXPECT_EQ(self->parent, syscall(__NR_getpid));
1867         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1868 }
1869
1870 TEST_F(TRACE_syscall, syscall_errno)
1871 {
1872         long ret;
1873
1874         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1875         ASSERT_EQ(0, ret);
1876
1877         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1878         ASSERT_EQ(0, ret);
1879
1880         /* openat has been skipped and an errno return. */
1881         EXPECT_SYSCALL_RETURN(-ESRCH, syscall(__NR_openat));
1882 }
1883
1884 TEST_F(TRACE_syscall, syscall_faked)
1885 {
1886         long ret;
1887
1888         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1889         ASSERT_EQ(0, ret);
1890
1891         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1892         ASSERT_EQ(0, ret);
1893
1894         /* gettid has been skipped and an altered return value stored. */
1895         EXPECT_SYSCALL_RETURN(45000, syscall(__NR_gettid));
1896 }
1897
1898 TEST_F(TRACE_syscall, skip_after_RET_TRACE)
1899 {
1900         struct sock_filter filter[] = {
1901                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1902                         offsetof(struct seccomp_data, nr)),
1903                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1904                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1905                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1906         };
1907         struct sock_fprog prog = {
1908                 .len = (unsigned short)ARRAY_SIZE(filter),
1909                 .filter = filter,
1910         };
1911         long ret;
1912
1913         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1914         ASSERT_EQ(0, ret);
1915
1916         /* Install fixture filter. */
1917         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1918         ASSERT_EQ(0, ret);
1919
1920         /* Install "errno on getppid" filter. */
1921         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1922         ASSERT_EQ(0, ret);
1923
1924         /* Tracer will redirect getpid to getppid, and we should see EPERM. */
1925         errno = 0;
1926         EXPECT_EQ(-1, syscall(__NR_getpid));
1927         EXPECT_EQ(EPERM, errno);
1928 }
1929
1930 TEST_F_SIGNAL(TRACE_syscall, kill_after_RET_TRACE, SIGSYS)
1931 {
1932         struct sock_filter filter[] = {
1933                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1934                         offsetof(struct seccomp_data, nr)),
1935                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1936                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1937                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1938         };
1939         struct sock_fprog prog = {
1940                 .len = (unsigned short)ARRAY_SIZE(filter),
1941                 .filter = filter,
1942         };
1943         long ret;
1944
1945         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1946         ASSERT_EQ(0, ret);
1947
1948         /* Install fixture filter. */
1949         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &self->prog, 0, 0);
1950         ASSERT_EQ(0, ret);
1951
1952         /* Install "death on getppid" filter. */
1953         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1954         ASSERT_EQ(0, ret);
1955
1956         /* Tracer will redirect getpid to getppid, and we should die. */
1957         EXPECT_NE(self->mypid, syscall(__NR_getpid));
1958 }
1959
1960 TEST_F(TRACE_syscall, skip_after_ptrace)
1961 {
1962         struct sock_filter filter[] = {
1963                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1964                         offsetof(struct seccomp_data, nr)),
1965                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1966                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EPERM),
1967                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
1968         };
1969         struct sock_fprog prog = {
1970                 .len = (unsigned short)ARRAY_SIZE(filter),
1971                 .filter = filter,
1972         };
1973         long ret;
1974
1975         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
1976         teardown_trace_fixture(_metadata, self->tracer);
1977         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
1978                                            true);
1979
1980         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
1981         ASSERT_EQ(0, ret);
1982
1983         /* Install "errno on getppid" filter. */
1984         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
1985         ASSERT_EQ(0, ret);
1986
1987         /* Tracer will redirect getpid to getppid, and we should see EPERM. */
1988         EXPECT_EQ(-1, syscall(__NR_getpid));
1989         EXPECT_EQ(EPERM, errno);
1990 }
1991
1992 TEST_F_SIGNAL(TRACE_syscall, kill_after_ptrace, SIGSYS)
1993 {
1994         struct sock_filter filter[] = {
1995                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
1996                         offsetof(struct seccomp_data, nr)),
1997                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getppid, 0, 1),
1998                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
1999                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2000         };
2001         struct sock_fprog prog = {
2002                 .len = (unsigned short)ARRAY_SIZE(filter),
2003                 .filter = filter,
2004         };
2005         long ret;
2006
2007         /* Swap SECCOMP_RET_TRACE tracer for PTRACE_SYSCALL tracer. */
2008         teardown_trace_fixture(_metadata, self->tracer);
2009         self->tracer = setup_trace_fixture(_metadata, tracer_ptrace, NULL,
2010                                            true);
2011
2012         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2013         ASSERT_EQ(0, ret);
2014
2015         /* Install "death on getppid" filter. */
2016         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2017         ASSERT_EQ(0, ret);
2018
2019         /* Tracer will redirect getpid to getppid, and we should die. */
2020         EXPECT_NE(self->mypid, syscall(__NR_getpid));
2021 }
2022
2023 TEST(seccomp_syscall)
2024 {
2025         struct sock_filter filter[] = {
2026                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2027         };
2028         struct sock_fprog prog = {
2029                 .len = (unsigned short)ARRAY_SIZE(filter),
2030                 .filter = filter,
2031         };
2032         long ret;
2033
2034         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2035         ASSERT_EQ(0, ret) {
2036                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2037         }
2038
2039         /* Reject insane operation. */
2040         ret = seccomp(-1, 0, &prog);
2041         ASSERT_NE(ENOSYS, errno) {
2042                 TH_LOG("Kernel does not support seccomp syscall!");
2043         }
2044         EXPECT_EQ(EINVAL, errno) {
2045                 TH_LOG("Did not reject crazy op value!");
2046         }
2047
2048         /* Reject strict with flags or pointer. */
2049         ret = seccomp(SECCOMP_SET_MODE_STRICT, -1, NULL);
2050         EXPECT_EQ(EINVAL, errno) {
2051                 TH_LOG("Did not reject mode strict with flags!");
2052         }
2053         ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, &prog);
2054         EXPECT_EQ(EINVAL, errno) {
2055                 TH_LOG("Did not reject mode strict with uargs!");
2056         }
2057
2058         /* Reject insane args for filter. */
2059         ret = seccomp(SECCOMP_SET_MODE_FILTER, -1, &prog);
2060         EXPECT_EQ(EINVAL, errno) {
2061                 TH_LOG("Did not reject crazy filter flags!");
2062         }
2063         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, NULL);
2064         EXPECT_EQ(EFAULT, errno) {
2065                 TH_LOG("Did not reject NULL filter!");
2066         }
2067
2068         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2069         EXPECT_EQ(0, errno) {
2070                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER: %s",
2071                         strerror(errno));
2072         }
2073 }
2074
2075 TEST(seccomp_syscall_mode_lock)
2076 {
2077         struct sock_filter filter[] = {
2078                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2079         };
2080         struct sock_fprog prog = {
2081                 .len = (unsigned short)ARRAY_SIZE(filter),
2082                 .filter = filter,
2083         };
2084         long ret;
2085
2086         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2087         ASSERT_EQ(0, ret) {
2088                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2089         }
2090
2091         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2092         ASSERT_NE(ENOSYS, errno) {
2093                 TH_LOG("Kernel does not support seccomp syscall!");
2094         }
2095         EXPECT_EQ(0, ret) {
2096                 TH_LOG("Could not install filter!");
2097         }
2098
2099         /* Make sure neither entry point will switch to strict. */
2100         ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_STRICT, 0, 0, 0);
2101         EXPECT_EQ(EINVAL, errno) {
2102                 TH_LOG("Switched to mode strict!");
2103         }
2104
2105         ret = seccomp(SECCOMP_SET_MODE_STRICT, 0, NULL);
2106         EXPECT_EQ(EINVAL, errno) {
2107                 TH_LOG("Switched to mode strict!");
2108         }
2109 }
2110
2111 /*
2112  * Test detection of known and unknown filter flags. Userspace needs to be able
2113  * to check if a filter flag is supported by the current kernel and a good way
2114  * of doing that is by attempting to enter filter mode, with the flag bit in
2115  * question set, and a NULL pointer for the _args_ parameter. EFAULT indicates
2116  * that the flag is valid and EINVAL indicates that the flag is invalid.
2117  */
2118 TEST(detect_seccomp_filter_flags)
2119 {
2120         unsigned int flags[] = { SECCOMP_FILTER_FLAG_TSYNC,
2121                                  SECCOMP_FILTER_FLAG_LOG,
2122                                  SECCOMP_FILTER_FLAG_SPEC_ALLOW };
2123         unsigned int flag, all_flags;
2124         int i;
2125         long ret;
2126
2127         /* Test detection of known-good filter flags */
2128         for (i = 0, all_flags = 0; i < ARRAY_SIZE(flags); i++) {
2129                 int bits = 0;
2130
2131                 flag = flags[i];
2132                 /* Make sure the flag is a single bit! */
2133                 while (flag) {
2134                         if (flag & 0x1)
2135                                 bits ++;
2136                         flag >>= 1;
2137                 }
2138                 ASSERT_EQ(1, bits);
2139                 flag = flags[i];
2140
2141                 ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2142                 ASSERT_NE(ENOSYS, errno) {
2143                         TH_LOG("Kernel does not support seccomp syscall!");
2144                 }
2145                 EXPECT_EQ(-1, ret);
2146                 EXPECT_EQ(EFAULT, errno) {
2147                         TH_LOG("Failed to detect that a known-good filter flag (0x%X) is supported!",
2148                                flag);
2149                 }
2150
2151                 all_flags |= flag;
2152         }
2153
2154         /* Test detection of all known-good filter flags */
2155         ret = seccomp(SECCOMP_SET_MODE_FILTER, all_flags, NULL);
2156         EXPECT_EQ(-1, ret);
2157         EXPECT_EQ(EFAULT, errno) {
2158                 TH_LOG("Failed to detect that all known-good filter flags (0x%X) are supported!",
2159                        all_flags);
2160         }
2161
2162         /* Test detection of an unknown filter flag */
2163         flag = -1;
2164         ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2165         EXPECT_EQ(-1, ret);
2166         EXPECT_EQ(EINVAL, errno) {
2167                 TH_LOG("Failed to detect that an unknown filter flag (0x%X) is unsupported!",
2168                        flag);
2169         }
2170
2171         /*
2172          * Test detection of an unknown filter flag that may simply need to be
2173          * added to this test
2174          */
2175         flag = flags[ARRAY_SIZE(flags) - 1] << 1;
2176         ret = seccomp(SECCOMP_SET_MODE_FILTER, flag, NULL);
2177         EXPECT_EQ(-1, ret);
2178         EXPECT_EQ(EINVAL, errno) {
2179                 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?",
2180                        flag);
2181         }
2182 }
2183
2184 TEST(TSYNC_first)
2185 {
2186         struct sock_filter filter[] = {
2187                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2188         };
2189         struct sock_fprog prog = {
2190                 .len = (unsigned short)ARRAY_SIZE(filter),
2191                 .filter = filter,
2192         };
2193         long ret;
2194
2195         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, NULL, 0, 0);
2196         ASSERT_EQ(0, ret) {
2197                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2198         }
2199
2200         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2201                       &prog);
2202         ASSERT_NE(ENOSYS, errno) {
2203                 TH_LOG("Kernel does not support seccomp syscall!");
2204         }
2205         EXPECT_EQ(0, ret) {
2206                 TH_LOG("Could not install initial filter with TSYNC!");
2207         }
2208 }
2209
2210 #define TSYNC_SIBLINGS 2
2211 struct tsync_sibling {
2212         pthread_t tid;
2213         pid_t system_tid;
2214         sem_t *started;
2215         pthread_cond_t *cond;
2216         pthread_mutex_t *mutex;
2217         int diverge;
2218         int num_waits;
2219         struct sock_fprog *prog;
2220         struct __test_metadata *metadata;
2221 };
2222
2223 /*
2224  * To avoid joining joined threads (which is not allowed by Bionic),
2225  * make sure we both successfully join and clear the tid to skip a
2226  * later join attempt during fixture teardown. Any remaining threads
2227  * will be directly killed during teardown.
2228  */
2229 #define PTHREAD_JOIN(tid, status)                                       \
2230         do {                                                            \
2231                 int _rc = pthread_join(tid, status);                    \
2232                 if (_rc) {                                              \
2233                         TH_LOG("pthread_join of tid %u failed: %d\n",   \
2234                                 (unsigned int)tid, _rc);                \
2235                 } else {                                                \
2236                         tid = 0;                                        \
2237                 }                                                       \
2238         } while (0)
2239
2240 FIXTURE_DATA(TSYNC) {
2241         struct sock_fprog root_prog, apply_prog;
2242         struct tsync_sibling sibling[TSYNC_SIBLINGS];
2243         sem_t started;
2244         pthread_cond_t cond;
2245         pthread_mutex_t mutex;
2246         int sibling_count;
2247 };
2248
2249 FIXTURE_SETUP(TSYNC)
2250 {
2251         struct sock_filter root_filter[] = {
2252                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2253         };
2254         struct sock_filter apply_filter[] = {
2255                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2256                         offsetof(struct seccomp_data, nr)),
2257                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 0, 1),
2258                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2259                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2260         };
2261
2262         memset(&self->root_prog, 0, sizeof(self->root_prog));
2263         memset(&self->apply_prog, 0, sizeof(self->apply_prog));
2264         memset(&self->sibling, 0, sizeof(self->sibling));
2265         self->root_prog.filter = malloc(sizeof(root_filter));
2266         ASSERT_NE(NULL, self->root_prog.filter);
2267         memcpy(self->root_prog.filter, &root_filter, sizeof(root_filter));
2268         self->root_prog.len = (unsigned short)ARRAY_SIZE(root_filter);
2269
2270         self->apply_prog.filter = malloc(sizeof(apply_filter));
2271         ASSERT_NE(NULL, self->apply_prog.filter);
2272         memcpy(self->apply_prog.filter, &apply_filter, sizeof(apply_filter));
2273         self->apply_prog.len = (unsigned short)ARRAY_SIZE(apply_filter);
2274
2275         self->sibling_count = 0;
2276         pthread_mutex_init(&self->mutex, NULL);
2277         pthread_cond_init(&self->cond, NULL);
2278         sem_init(&self->started, 0, 0);
2279         self->sibling[0].tid = 0;
2280         self->sibling[0].cond = &self->cond;
2281         self->sibling[0].started = &self->started;
2282         self->sibling[0].mutex = &self->mutex;
2283         self->sibling[0].diverge = 0;
2284         self->sibling[0].num_waits = 1;
2285         self->sibling[0].prog = &self->root_prog;
2286         self->sibling[0].metadata = _metadata;
2287         self->sibling[1].tid = 0;
2288         self->sibling[1].cond = &self->cond;
2289         self->sibling[1].started = &self->started;
2290         self->sibling[1].mutex = &self->mutex;
2291         self->sibling[1].diverge = 0;
2292         self->sibling[1].prog = &self->root_prog;
2293         self->sibling[1].num_waits = 1;
2294         self->sibling[1].metadata = _metadata;
2295 }
2296
2297 FIXTURE_TEARDOWN(TSYNC)
2298 {
2299         int sib = 0;
2300
2301         if (self->root_prog.filter)
2302                 free(self->root_prog.filter);
2303         if (self->apply_prog.filter)
2304                 free(self->apply_prog.filter);
2305
2306         for ( ; sib < self->sibling_count; ++sib) {
2307                 struct tsync_sibling *s = &self->sibling[sib];
2308
2309                 if (!s->tid)
2310                         continue;
2311                 /*
2312                  * If a thread is still running, it may be stuck, so hit
2313                  * it over the head really hard.
2314                  */
2315                 pthread_kill(s->tid, 9);
2316         }
2317         pthread_mutex_destroy(&self->mutex);
2318         pthread_cond_destroy(&self->cond);
2319         sem_destroy(&self->started);
2320 }
2321
2322 void *tsync_sibling(void *data)
2323 {
2324         long ret = 0;
2325         struct tsync_sibling *me = data;
2326
2327         me->system_tid = syscall(__NR_gettid);
2328
2329         pthread_mutex_lock(me->mutex);
2330         if (me->diverge) {
2331                 /* Just re-apply the root prog to fork the tree */
2332                 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER,
2333                                 me->prog, 0, 0);
2334         }
2335         sem_post(me->started);
2336         /* Return outside of started so parent notices failures. */
2337         if (ret) {
2338                 pthread_mutex_unlock(me->mutex);
2339                 return (void *)SIBLING_EXIT_FAILURE;
2340         }
2341         do {
2342                 pthread_cond_wait(me->cond, me->mutex);
2343                 me->num_waits = me->num_waits - 1;
2344         } while (me->num_waits);
2345         pthread_mutex_unlock(me->mutex);
2346
2347         ret = prctl(PR_GET_NO_NEW_PRIVS, 0, 0, 0, 0);
2348         if (!ret)
2349                 return (void *)SIBLING_EXIT_NEWPRIVS;
2350         read(0, NULL, 0);
2351         return (void *)SIBLING_EXIT_UNKILLED;
2352 }
2353
2354 void tsync_start_sibling(struct tsync_sibling *sibling)
2355 {
2356         pthread_create(&sibling->tid, NULL, tsync_sibling, (void *)sibling);
2357 }
2358
2359 TEST_F(TSYNC, siblings_fail_prctl)
2360 {
2361         long ret;
2362         void *status;
2363         struct sock_filter filter[] = {
2364                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2365                         offsetof(struct seccomp_data, nr)),
2366                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_prctl, 0, 1),
2367                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO | EINVAL),
2368                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2369         };
2370         struct sock_fprog prog = {
2371                 .len = (unsigned short)ARRAY_SIZE(filter),
2372                 .filter = filter,
2373         };
2374
2375         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2376                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2377         }
2378
2379         /* Check prctl failure detection by requesting sib 0 diverge. */
2380         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog);
2381         ASSERT_NE(ENOSYS, errno) {
2382                 TH_LOG("Kernel does not support seccomp syscall!");
2383         }
2384         ASSERT_EQ(0, ret) {
2385                 TH_LOG("setting filter failed");
2386         }
2387
2388         self->sibling[0].diverge = 1;
2389         tsync_start_sibling(&self->sibling[0]);
2390         tsync_start_sibling(&self->sibling[1]);
2391
2392         while (self->sibling_count < TSYNC_SIBLINGS) {
2393                 sem_wait(&self->started);
2394                 self->sibling_count++;
2395         }
2396
2397         /* Signal the threads to clean up*/
2398         pthread_mutex_lock(&self->mutex);
2399         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2400                 TH_LOG("cond broadcast non-zero");
2401         }
2402         pthread_mutex_unlock(&self->mutex);
2403
2404         /* Ensure diverging sibling failed to call prctl. */
2405         PTHREAD_JOIN(self->sibling[0].tid, &status);
2406         EXPECT_EQ(SIBLING_EXIT_FAILURE, (long)status);
2407         PTHREAD_JOIN(self->sibling[1].tid, &status);
2408         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2409 }
2410
2411 TEST_F(TSYNC, two_siblings_with_ancestor)
2412 {
2413         long ret;
2414         void *status;
2415
2416         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2417                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2418         }
2419
2420         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2421         ASSERT_NE(ENOSYS, errno) {
2422                 TH_LOG("Kernel does not support seccomp syscall!");
2423         }
2424         ASSERT_EQ(0, ret) {
2425                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2426         }
2427         tsync_start_sibling(&self->sibling[0]);
2428         tsync_start_sibling(&self->sibling[1]);
2429
2430         while (self->sibling_count < TSYNC_SIBLINGS) {
2431                 sem_wait(&self->started);
2432                 self->sibling_count++;
2433         }
2434
2435         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2436                       &self->apply_prog);
2437         ASSERT_EQ(0, ret) {
2438                 TH_LOG("Could install filter on all threads!");
2439         }
2440         /* Tell the siblings to test the policy */
2441         pthread_mutex_lock(&self->mutex);
2442         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2443                 TH_LOG("cond broadcast non-zero");
2444         }
2445         pthread_mutex_unlock(&self->mutex);
2446         /* Ensure they are both killed and don't exit cleanly. */
2447         PTHREAD_JOIN(self->sibling[0].tid, &status);
2448         EXPECT_EQ(0x0, (long)status);
2449         PTHREAD_JOIN(self->sibling[1].tid, &status);
2450         EXPECT_EQ(0x0, (long)status);
2451 }
2452
2453 TEST_F(TSYNC, two_sibling_want_nnp)
2454 {
2455         void *status;
2456
2457         /* start siblings before any prctl() operations */
2458         tsync_start_sibling(&self->sibling[0]);
2459         tsync_start_sibling(&self->sibling[1]);
2460         while (self->sibling_count < TSYNC_SIBLINGS) {
2461                 sem_wait(&self->started);
2462                 self->sibling_count++;
2463         }
2464
2465         /* Tell the siblings to test no policy */
2466         pthread_mutex_lock(&self->mutex);
2467         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2468                 TH_LOG("cond broadcast non-zero");
2469         }
2470         pthread_mutex_unlock(&self->mutex);
2471
2472         /* Ensure they are both upset about lacking nnp. */
2473         PTHREAD_JOIN(self->sibling[0].tid, &status);
2474         EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2475         PTHREAD_JOIN(self->sibling[1].tid, &status);
2476         EXPECT_EQ(SIBLING_EXIT_NEWPRIVS, (long)status);
2477 }
2478
2479 TEST_F(TSYNC, two_siblings_with_no_filter)
2480 {
2481         long ret;
2482         void *status;
2483
2484         /* start siblings before any prctl() operations */
2485         tsync_start_sibling(&self->sibling[0]);
2486         tsync_start_sibling(&self->sibling[1]);
2487         while (self->sibling_count < TSYNC_SIBLINGS) {
2488                 sem_wait(&self->started);
2489                 self->sibling_count++;
2490         }
2491
2492         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2493                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2494         }
2495
2496         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2497                       &self->apply_prog);
2498         ASSERT_NE(ENOSYS, errno) {
2499                 TH_LOG("Kernel does not support seccomp syscall!");
2500         }
2501         ASSERT_EQ(0, ret) {
2502                 TH_LOG("Could install filter on all threads!");
2503         }
2504
2505         /* Tell the siblings to test the policy */
2506         pthread_mutex_lock(&self->mutex);
2507         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2508                 TH_LOG("cond broadcast non-zero");
2509         }
2510         pthread_mutex_unlock(&self->mutex);
2511
2512         /* Ensure they are both killed and don't exit cleanly. */
2513         PTHREAD_JOIN(self->sibling[0].tid, &status);
2514         EXPECT_EQ(0x0, (long)status);
2515         PTHREAD_JOIN(self->sibling[1].tid, &status);
2516         EXPECT_EQ(0x0, (long)status);
2517 }
2518
2519 TEST_F(TSYNC, two_siblings_with_one_divergence)
2520 {
2521         long ret;
2522         void *status;
2523
2524         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2525                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2526         }
2527
2528         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2529         ASSERT_NE(ENOSYS, errno) {
2530                 TH_LOG("Kernel does not support seccomp syscall!");
2531         }
2532         ASSERT_EQ(0, ret) {
2533                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2534         }
2535         self->sibling[0].diverge = 1;
2536         tsync_start_sibling(&self->sibling[0]);
2537         tsync_start_sibling(&self->sibling[1]);
2538
2539         while (self->sibling_count < TSYNC_SIBLINGS) {
2540                 sem_wait(&self->started);
2541                 self->sibling_count++;
2542         }
2543
2544         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2545                       &self->apply_prog);
2546         ASSERT_EQ(self->sibling[0].system_tid, ret) {
2547                 TH_LOG("Did not fail on diverged sibling.");
2548         }
2549
2550         /* Wake the threads */
2551         pthread_mutex_lock(&self->mutex);
2552         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2553                 TH_LOG("cond broadcast non-zero");
2554         }
2555         pthread_mutex_unlock(&self->mutex);
2556
2557         /* Ensure they are both unkilled. */
2558         PTHREAD_JOIN(self->sibling[0].tid, &status);
2559         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2560         PTHREAD_JOIN(self->sibling[1].tid, &status);
2561         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2562 }
2563
2564 TEST_F(TSYNC, two_siblings_not_under_filter)
2565 {
2566         long ret, sib;
2567         void *status;
2568
2569         ASSERT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2570                 TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2571         }
2572
2573         /*
2574          * Sibling 0 will have its own seccomp policy
2575          * and Sibling 1 will not be under seccomp at
2576          * all. Sibling 1 will enter seccomp and 0
2577          * will cause failure.
2578          */
2579         self->sibling[0].diverge = 1;
2580         tsync_start_sibling(&self->sibling[0]);
2581         tsync_start_sibling(&self->sibling[1]);
2582
2583         while (self->sibling_count < TSYNC_SIBLINGS) {
2584                 sem_wait(&self->started);
2585                 self->sibling_count++;
2586         }
2587
2588         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &self->root_prog);
2589         ASSERT_NE(ENOSYS, errno) {
2590                 TH_LOG("Kernel does not support seccomp syscall!");
2591         }
2592         ASSERT_EQ(0, ret) {
2593                 TH_LOG("Kernel does not support SECCOMP_SET_MODE_FILTER!");
2594         }
2595
2596         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2597                       &self->apply_prog);
2598         ASSERT_EQ(ret, self->sibling[0].system_tid) {
2599                 TH_LOG("Did not fail on diverged sibling.");
2600         }
2601         sib = 1;
2602         if (ret == self->sibling[0].system_tid)
2603                 sib = 0;
2604
2605         pthread_mutex_lock(&self->mutex);
2606
2607         /* Increment the other siblings num_waits so we can clean up
2608          * the one we just saw.
2609          */
2610         self->sibling[!sib].num_waits += 1;
2611
2612         /* Signal the thread to clean up*/
2613         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2614                 TH_LOG("cond broadcast non-zero");
2615         }
2616         pthread_mutex_unlock(&self->mutex);
2617         PTHREAD_JOIN(self->sibling[sib].tid, &status);
2618         EXPECT_EQ(SIBLING_EXIT_UNKILLED, (long)status);
2619         /* Poll for actual task death. pthread_join doesn't guarantee it. */
2620         while (!kill(self->sibling[sib].system_tid, 0))
2621                 sleep(0.1);
2622         /* Switch to the remaining sibling */
2623         sib = !sib;
2624
2625         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2626                       &self->apply_prog);
2627         ASSERT_EQ(0, ret) {
2628                 TH_LOG("Expected the remaining sibling to sync");
2629         };
2630
2631         pthread_mutex_lock(&self->mutex);
2632
2633         /* If remaining sibling didn't have a chance to wake up during
2634          * the first broadcast, manually reduce the num_waits now.
2635          */
2636         if (self->sibling[sib].num_waits > 1)
2637                 self->sibling[sib].num_waits = 1;
2638         ASSERT_EQ(0, pthread_cond_broadcast(&self->cond)) {
2639                 TH_LOG("cond broadcast non-zero");
2640         }
2641         pthread_mutex_unlock(&self->mutex);
2642         PTHREAD_JOIN(self->sibling[sib].tid, &status);
2643         EXPECT_EQ(0, (long)status);
2644         /* Poll for actual task death. pthread_join doesn't guarantee it. */
2645         while (!kill(self->sibling[sib].system_tid, 0))
2646                 sleep(0.1);
2647
2648         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_TSYNC,
2649                       &self->apply_prog);
2650         ASSERT_EQ(0, ret);  /* just us chickens */
2651 }
2652
2653 /* Make sure restarted syscalls are seen directly as "restart_syscall". */
2654 TEST(syscall_restart)
2655 {
2656         long ret;
2657         unsigned long msg;
2658         pid_t child_pid;
2659         int pipefd[2];
2660         int status;
2661         siginfo_t info = { };
2662         struct sock_filter filter[] = {
2663                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2664                          offsetof(struct seccomp_data, nr)),
2665
2666 #ifdef __NR_sigreturn
2667                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_sigreturn, 6, 0),
2668 #endif
2669                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_read, 5, 0),
2670                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_exit, 4, 0),
2671                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_rt_sigreturn, 3, 0),
2672                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_nanosleep, 4, 0),
2673                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_restart_syscall, 4, 0),
2674
2675                 /* Allow __NR_write for easy logging. */
2676                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_write, 0, 1),
2677                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2678                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2679                 /* The nanosleep jump target. */
2680                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x100),
2681                 /* The restart_syscall jump target. */
2682                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE|0x200),
2683         };
2684         struct sock_fprog prog = {
2685                 .len = (unsigned short)ARRAY_SIZE(filter),
2686                 .filter = filter,
2687         };
2688 #if defined(__arm__)
2689         struct utsname utsbuf;
2690 #endif
2691
2692         ASSERT_EQ(0, pipe(pipefd));
2693
2694         child_pid = fork();
2695         ASSERT_LE(0, child_pid);
2696         if (child_pid == 0) {
2697                 /* Child uses EXPECT not ASSERT to deliver status correctly. */
2698                 char buf = ' ';
2699                 struct timespec timeout = { };
2700
2701                 /* Attach parent as tracer and stop. */
2702                 EXPECT_EQ(0, ptrace(PTRACE_TRACEME));
2703                 EXPECT_EQ(0, raise(SIGSTOP));
2704
2705                 EXPECT_EQ(0, close(pipefd[1]));
2706
2707                 EXPECT_EQ(0, prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0)) {
2708                         TH_LOG("Kernel does not support PR_SET_NO_NEW_PRIVS!");
2709                 }
2710
2711                 ret = prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog, 0, 0);
2712                 EXPECT_EQ(0, ret) {
2713                         TH_LOG("Failed to install filter!");
2714                 }
2715
2716                 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2717                         TH_LOG("Failed to read() sync from parent");
2718                 }
2719                 EXPECT_EQ('.', buf) {
2720                         TH_LOG("Failed to get sync data from read()");
2721                 }
2722
2723                 /* Start nanosleep to be interrupted. */
2724                 timeout.tv_sec = 1;
2725                 errno = 0;
2726                 EXPECT_EQ(0, nanosleep(&timeout, NULL)) {
2727                         TH_LOG("Call to nanosleep() failed (errno %d)", errno);
2728                 }
2729
2730                 /* Read final sync from parent. */
2731                 EXPECT_EQ(1, read(pipefd[0], &buf, 1)) {
2732                         TH_LOG("Failed final read() from parent");
2733                 }
2734                 EXPECT_EQ('!', buf) {
2735                         TH_LOG("Failed to get final data from read()");
2736                 }
2737
2738                 /* Directly report the status of our test harness results. */
2739                 syscall(__NR_exit, _metadata->passed ? EXIT_SUCCESS
2740                                                      : EXIT_FAILURE);
2741         }
2742         EXPECT_EQ(0, close(pipefd[0]));
2743
2744         /* Attach to child, setup options, and release. */
2745         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2746         ASSERT_EQ(true, WIFSTOPPED(status));
2747         ASSERT_EQ(0, ptrace(PTRACE_SETOPTIONS, child_pid, NULL,
2748                             PTRACE_O_TRACESECCOMP));
2749         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2750         ASSERT_EQ(1, write(pipefd[1], ".", 1));
2751
2752         /* Wait for nanosleep() to start. */
2753         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2754         ASSERT_EQ(true, WIFSTOPPED(status));
2755         ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2756         ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2757         ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2758         ASSERT_EQ(0x100, msg);
2759         EXPECT_EQ(__NR_nanosleep, get_syscall(_metadata, child_pid));
2760
2761         /* Might as well check siginfo for sanity while we're here. */
2762         ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2763         ASSERT_EQ(SIGTRAP, info.si_signo);
2764         ASSERT_EQ(SIGTRAP | (PTRACE_EVENT_SECCOMP << 8), info.si_code);
2765         EXPECT_EQ(0, info.si_errno);
2766         EXPECT_EQ(getuid(), info.si_uid);
2767         /* Verify signal delivery came from child (seccomp-triggered). */
2768         EXPECT_EQ(child_pid, info.si_pid);
2769
2770         /* Interrupt nanosleep with SIGSTOP (which we'll need to handle). */
2771         ASSERT_EQ(0, kill(child_pid, SIGSTOP));
2772         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2773         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2774         ASSERT_EQ(true, WIFSTOPPED(status));
2775         ASSERT_EQ(SIGSTOP, WSTOPSIG(status));
2776         /* Verify signal delivery came from parent now. */
2777         ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child_pid, NULL, &info));
2778         EXPECT_EQ(getpid(), info.si_pid);
2779
2780         /* Restart nanosleep with SIGCONT, which triggers restart_syscall. */
2781         ASSERT_EQ(0, kill(child_pid, SIGCONT));
2782         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2783         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2784         ASSERT_EQ(true, WIFSTOPPED(status));
2785         ASSERT_EQ(SIGCONT, WSTOPSIG(status));
2786         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2787
2788         /* Wait for restart_syscall() to start. */
2789         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2790         ASSERT_EQ(true, WIFSTOPPED(status));
2791         ASSERT_EQ(SIGTRAP, WSTOPSIG(status));
2792         ASSERT_EQ(PTRACE_EVENT_SECCOMP, (status >> 16));
2793         ASSERT_EQ(0, ptrace(PTRACE_GETEVENTMSG, child_pid, NULL, &msg));
2794
2795         ASSERT_EQ(0x200, msg);
2796         ret = get_syscall(_metadata, child_pid);
2797 #if defined(__arm__)
2798         /*
2799          * FIXME:
2800          * - native ARM registers do NOT expose true syscall.
2801          * - compat ARM registers on ARM64 DO expose true syscall.
2802          */
2803         ASSERT_EQ(0, uname(&utsbuf));
2804         if (strncmp(utsbuf.machine, "arm", 3) == 0) {
2805                 EXPECT_EQ(__NR_nanosleep, ret);
2806         } else
2807 #endif
2808         {
2809                 EXPECT_EQ(__NR_restart_syscall, ret);
2810         }
2811
2812         /* Write again to end test. */
2813         ASSERT_EQ(0, ptrace(PTRACE_CONT, child_pid, NULL, 0));
2814         ASSERT_EQ(1, write(pipefd[1], "!", 1));
2815         EXPECT_EQ(0, close(pipefd[1]));
2816
2817         ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
2818         if (WIFSIGNALED(status) || WEXITSTATUS(status))
2819                 _metadata->passed = 0;
2820 }
2821
2822 TEST_SIGNAL(filter_flag_log, SIGSYS)
2823 {
2824         struct sock_filter allow_filter[] = {
2825                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2826         };
2827         struct sock_filter kill_filter[] = {
2828                 BPF_STMT(BPF_LD|BPF_W|BPF_ABS,
2829                         offsetof(struct seccomp_data, nr)),
2830                 BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, __NR_getpid, 0, 1),
2831                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL),
2832                 BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2833         };
2834         struct sock_fprog allow_prog = {
2835                 .len = (unsigned short)ARRAY_SIZE(allow_filter),
2836                 .filter = allow_filter,
2837         };
2838         struct sock_fprog kill_prog = {
2839                 .len = (unsigned short)ARRAY_SIZE(kill_filter),
2840                 .filter = kill_filter,
2841         };
2842         long ret;
2843         pid_t parent = getppid();
2844
2845         ret = prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
2846         ASSERT_EQ(0, ret);
2847
2848         /* Verify that the FILTER_FLAG_LOG flag isn't accepted in strict mode */
2849         ret = seccomp(SECCOMP_SET_MODE_STRICT, SECCOMP_FILTER_FLAG_LOG,
2850                       &allow_prog);
2851         ASSERT_NE(ENOSYS, errno) {
2852                 TH_LOG("Kernel does not support seccomp syscall!");
2853         }
2854         EXPECT_NE(0, ret) {
2855                 TH_LOG("Kernel accepted FILTER_FLAG_LOG flag in strict mode!");
2856         }
2857         EXPECT_EQ(EINVAL, errno) {
2858                 TH_LOG("Kernel returned unexpected errno for FILTER_FLAG_LOG flag in strict mode!");
2859         }
2860
2861         /* Verify that a simple, permissive filter can be added with no flags */
2862         ret = seccomp(SECCOMP_SET_MODE_FILTER, 0, &allow_prog);
2863         EXPECT_EQ(0, ret);
2864
2865         /* See if the same filter can be added with the FILTER_FLAG_LOG flag */
2866         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2867                       &allow_prog);
2868         ASSERT_NE(EINVAL, errno) {
2869                 TH_LOG("Kernel does not support the FILTER_FLAG_LOG flag!");
2870         }
2871         EXPECT_EQ(0, ret);
2872
2873         /* Ensure that the kill filter works with the FILTER_FLAG_LOG flag */
2874         ret = seccomp(SECCOMP_SET_MODE_FILTER, SECCOMP_FILTER_FLAG_LOG,
2875                       &kill_prog);
2876         EXPECT_EQ(0, ret);
2877
2878         EXPECT_EQ(parent, syscall(__NR_getppid));
2879         /* getpid() should never return. */
2880         EXPECT_EQ(0, syscall(__NR_getpid));
2881 }
2882
2883 TEST(get_action_avail)
2884 {
2885         __u32 actions[] = { SECCOMP_RET_KILL_THREAD, SECCOMP_RET_TRAP,
2886                             SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE,
2887                             SECCOMP_RET_LOG,   SECCOMP_RET_ALLOW };
2888         __u32 unknown_action = 0x10000000U;
2889         int i;
2890         long ret;
2891
2892         ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[0]);
2893         ASSERT_NE(ENOSYS, errno) {
2894                 TH_LOG("Kernel does not support seccomp syscall!");
2895         }
2896         ASSERT_NE(EINVAL, errno) {
2897                 TH_LOG("Kernel does not support SECCOMP_GET_ACTION_AVAIL operation!");
2898         }
2899         EXPECT_EQ(ret, 0);
2900
2901         for (i = 0; i < ARRAY_SIZE(actions); i++) {
2902                 ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &actions[i]);
2903                 EXPECT_EQ(ret, 0) {
2904                         TH_LOG("Expected action (0x%X) not available!",
2905                                actions[i]);
2906                 }
2907         }
2908
2909         /* Check that an unknown action is handled properly (EOPNOTSUPP) */
2910         ret = seccomp(SECCOMP_GET_ACTION_AVAIL, 0, &unknown_action);
2911         EXPECT_EQ(ret, -1);
2912         EXPECT_EQ(errno, EOPNOTSUPP);
2913 }
2914
2915 TEST(get_metadata)
2916 {
2917         pid_t pid;
2918         int pipefd[2];
2919         char buf;
2920         struct seccomp_metadata md;
2921         long ret;
2922
2923         /* Only real root can get metadata. */
2924         if (geteuid()) {
2925                 XFAIL(return, "get_metadata requires real root");
2926                 return;
2927         }
2928
2929         ASSERT_EQ(0, pipe(pipefd));
2930
2931         pid = fork();
2932         ASSERT_GE(pid, 0);
2933         if (pid == 0) {
2934                 struct sock_filter filter[] = {
2935                         BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW),
2936                 };
2937                 struct sock_fprog prog = {
2938                         .len = (unsigned short)ARRAY_SIZE(filter),
2939                         .filter = filter,
2940                 };
2941
2942                 /* one with log, one without */
2943                 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER,
2944                                      SECCOMP_FILTER_FLAG_LOG, &prog));
2945                 ASSERT_EQ(0, seccomp(SECCOMP_SET_MODE_FILTER, 0, &prog));
2946
2947                 ASSERT_EQ(0, close(pipefd[0]));
2948                 ASSERT_EQ(1, write(pipefd[1], "1", 1));
2949                 ASSERT_EQ(0, close(pipefd[1]));
2950
2951                 while (1)
2952                         sleep(100);
2953         }
2954
2955         ASSERT_EQ(0, close(pipefd[1]));
2956         ASSERT_EQ(1, read(pipefd[0], &buf, 1));
2957
2958         ASSERT_EQ(0, ptrace(PTRACE_ATTACH, pid));
2959         ASSERT_EQ(pid, waitpid(pid, NULL, 0));
2960
2961         /* Past here must not use ASSERT or child process is never killed. */
2962
2963         md.filter_off = 0;
2964         errno = 0;
2965         ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
2966         EXPECT_EQ(sizeof(md), ret) {
2967                 if (errno == EINVAL)
2968                         XFAIL(goto skip, "Kernel does not support PTRACE_SECCOMP_GET_METADATA (missing CONFIG_CHECKPOINT_RESTORE?)");
2969         }
2970
2971         EXPECT_EQ(md.flags, SECCOMP_FILTER_FLAG_LOG);
2972         EXPECT_EQ(md.filter_off, 0);
2973
2974         md.filter_off = 1;
2975         ret = ptrace(PTRACE_SECCOMP_GET_METADATA, pid, sizeof(md), &md);
2976         EXPECT_EQ(sizeof(md), ret);
2977         EXPECT_EQ(md.flags, 0);
2978         EXPECT_EQ(md.filter_off, 1);
2979
2980 skip:
2981         ASSERT_EQ(0, kill(pid, SIGKILL));
2982 }
2983
2984 /*
2985  * TODO:
2986  * - add microbenchmarks
2987  * - expand NNP testing
2988  * - better arch-specific TRACE and TRAP handlers.
2989  * - endianness checking when appropriate
2990  * - 64-bit arg prodding
2991  * - arch value testing (x86 modes especially)
2992  * - verify that FILTER_FLAG_LOG filters generate log messages
2993  * - verify that RET_LOG generates log messages
2994  * - ...
2995  */
2996
2997 TEST_HARNESS_MAIN