// https://syzkaller.appspot.com/bug?id=ebdd919d6b0b31f25602378e9f934129e122e808 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include unsigned long long procid; static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms() { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void use_temporary_dir() { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } static void vsnprintf_check(char* str, size_t size, const char* format, va_list args) { int rv; rv = vsnprintf(str, size, format, args); if (rv < 0) exit(1); if ((size_t)rv >= size) exit(1); } #define COMMAND_MAX_LEN 128 #define PATH_PREFIX \ "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin " #define PATH_PREFIX_LEN (sizeof(PATH_PREFIX) - 1) static void execute_command(bool panic, const char* format, ...) { va_list args; char command[PATH_PREFIX_LEN + COMMAND_MAX_LEN]; int rv; va_start(args, format); memcpy(command, PATH_PREFIX, PATH_PREFIX_LEN); vsnprintf_check(command + PATH_PREFIX_LEN, COMMAND_MAX_LEN, format, args); va_end(args); rv = system(command); if (rv) { if (panic) exit(1); } } static int tunfd = -1; static int tun_frags_enabled; #define SYZ_TUN_MAX_PACKET_SIZE 1000 #define TUN_IFACE "syz_tun" #define LOCAL_MAC "aa:aa:aa:aa:aa:aa" #define REMOTE_MAC "aa:aa:aa:aa:aa:bb" #define LOCAL_IPV4 "172.20.20.170" #define REMOTE_IPV4 "172.20.20.187" #define LOCAL_IPV6 "fe80::aa" #define REMOTE_IPV6 "fe80::bb" #define IFF_NAPI 0x0010 #define IFF_NAPI_FRAGS 0x0020 static void initialize_tun(void) { tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK); if (tunfd == -1) { printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n"); printf("otherwise fuzzing or reproducing might not work as intended\n"); return; } const int kTunFd = 240; if (dup2(tunfd, kTunFd) < 0) exit(1); close(tunfd); tunfd = kTunFd; struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ); ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_NAPI | IFF_NAPI_FRAGS; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) { ifr.ifr_flags = IFF_TAP | IFF_NO_PI; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) exit(1); } if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0) exit(1); tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0; execute_command(0, "sysctl -w net.ipv6.conf.%s.accept_dad=0", TUN_IFACE); execute_command(0, "sysctl -w net.ipv6.conf.%s.router_solicitations=0", TUN_IFACE); execute_command(1, "ip link set dev %s address %s", TUN_IFACE, LOCAL_MAC); execute_command(1, "ip addr add %s/24 dev %s", LOCAL_IPV4, TUN_IFACE); execute_command(1, "ip neigh add %s lladdr %s dev %s nud permanent", REMOTE_IPV4, REMOTE_MAC, TUN_IFACE); execute_command(0, "ip -6 addr add %s/120 dev %s", LOCAL_IPV6, TUN_IFACE); execute_command(0, "ip -6 neigh add %s lladdr %s dev %s nud permanent", REMOTE_IPV6, REMOTE_MAC, TUN_IFACE); execute_command(1, "ip link set dev %s up", TUN_IFACE); } static int read_tun(char* data, int size) { if (tunfd < 0) return -1; int rv = read(tunfd, data, size); if (rv < 0) { if (errno == EAGAIN) return -1; if (errno == EBADFD) return -1; exit(1); } return rv; } static void flush_tun() { char data[SYZ_TUN_MAX_PACKET_SIZE]; while (read_tun(&data[0], sizeof(data)) != -1) { } } static void setup_common() { } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setsid(); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 160 << 20; setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } } int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); setup_common(); sandbox_common(); if (unshare(CLONE_NEWNET)) { } initialize_tun(); loop(); exit(1); } static void remove_dir(const char* dir) { DIR* dp; struct dirent* ep; int iter = 0; retry: while (umount2(dir, MNT_DETACH) == 0) { } dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exit(1); } exit(1); } while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); while (umount2(filename, MNT_DETACH) == 0) { } struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { if (unlink(filename) == 0) break; if (errno == EROFS) { break; } if (errno != EBUSY || i > 100) exit(1); if (umount2(filename, MNT_DETACH)) exit(1); } } closedir(dp); int i; for (i = 0;; i++) { if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EROFS) { break; } if (errno == EBUSY) { if (umount2(dir, MNT_DETACH)) exit(1); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exit(1); } } #define SYZ_HAVE_SETUP_TEST 1 static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); flush_tun(); } #define SYZ_HAVE_RESET_TEST 1 static void reset_test() { int fd; for (fd = 3; fd < 30; fd++) close(fd); } static void execute_one(); #define WAIT_FLAGS __WALL static void loop() { int iter; for (iter = 0;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { setup_test(); if (chdir(cwdbuf)) exit(1); execute_one(); reset_test(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5 * 1000) continue; kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, WAIT_FLAGS) != pid) { } break; } remove_dir(cwdbuf); } } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_one() { long res = 0; res = syscall(__NR_socket, 0xa, 0x2100000000000002, 0); if (res != -1) r[0] = res; res = syscall(__NR_socket, 0x10, 3, 6); if (res != -1) r[1] = res; *(uint16_t*)0x20000080 = 0x10; *(uint16_t*)0x20000082 = 0; *(uint32_t*)0x20000084 = 0; *(uint32_t*)0x20000088 = 1; syscall(__NR_bind, r[1], 0x20000080, 0xc); *(uint32_t*)0x20000140 = htobe32(0); *(uint64_t*)0x20000150 = htobe64(0); *(uint64_t*)0x20000158 = htobe64(1); *(uint16_t*)0x20000160 = htobe16(0); *(uint16_t*)0x20000162 = htobe16(0); *(uint16_t*)0x20000164 = htobe16(0); *(uint16_t*)0x20000166 = htobe16(0); *(uint16_t*)0x20000168 = 0xa; *(uint8_t*)0x2000016a = 0; *(uint8_t*)0x2000016b = 0; *(uint8_t*)0x2000016c = 0; *(uint32_t*)0x20000170 = 0; *(uint32_t*)0x20000174 = 0; *(uint64_t*)0x20000178 = 0; *(uint64_t*)0x20000180 = 0; *(uint64_t*)0x20000188 = 0; *(uint64_t*)0x20000190 = 0; *(uint64_t*)0x20000198 = 0; *(uint64_t*)0x200001a0 = 0; *(uint64_t*)0x200001a8 = 0; *(uint64_t*)0x200001b0 = 0; *(uint64_t*)0x200001b8 = 0; *(uint64_t*)0x200001c0 = 0; *(uint64_t*)0x200001c8 = 0; *(uint64_t*)0x200001d0 = 0; *(uint32_t*)0x200001d8 = 0; *(uint32_t*)0x200001dc = 0; *(uint8_t*)0x200001e0 = 1; *(uint8_t*)0x200001e1 = 0; *(uint8_t*)0x200001e2 = 0; *(uint8_t*)0x200001e3 = 0; *(uint8_t*)0x200001e8 = 0; *(uint8_t*)0x200001e9 = 0; *(uint8_t*)0x200001ea = 0; *(uint8_t*)0x200001eb = 0; *(uint8_t*)0x200001ec = 0; *(uint8_t*)0x200001ed = 0; *(uint8_t*)0x200001ee = 0; *(uint8_t*)0x200001ef = 0; *(uint8_t*)0x200001f0 = 0; *(uint8_t*)0x200001f1 = 0; *(uint8_t*)0x200001f2 = 0; *(uint8_t*)0x200001f3 = 0; *(uint8_t*)0x200001f4 = 0; *(uint8_t*)0x200001f5 = 0; *(uint8_t*)0x200001f6 = 0; *(uint8_t*)0x200001f7 = 0; *(uint32_t*)0x200001f8 = htobe32(0); *(uint8_t*)0x200001fc = 0x2b; *(uint16_t*)0x20000200 = 0; *(uint64_t*)0x20000204 = htobe64(0); *(uint64_t*)0x2000020c = htobe64(1); *(uint32_t*)0x20000214 = 0; *(uint8_t*)0x20000218 = 0; *(uint8_t*)0x20000219 = 0; *(uint8_t*)0x2000021a = 3; *(uint32_t*)0x2000021c = 0; *(uint32_t*)0x20000220 = 0; *(uint32_t*)0x20000224 = 0; syscall(__NR_setsockopt, r[0], 0x29, 0x23, 0x20000140, 0xe8); *(uint16_t*)0x20000280 = 0xa; *(uint16_t*)0x20000282 = htobe16(0x4e20); *(uint32_t*)0x20000284 = 0; *(uint8_t*)0x20000288 = 0xfe; *(uint8_t*)0x20000289 = 0x80; *(uint8_t*)0x2000028a = 0; *(uint8_t*)0x2000028b = 0; *(uint8_t*)0x2000028c = 0; *(uint8_t*)0x2000028d = 0; *(uint8_t*)0x2000028e = 0; *(uint8_t*)0x2000028f = 0; *(uint8_t*)0x20000290 = 0; *(uint8_t*)0x20000291 = 0; *(uint8_t*)0x20000292 = 0; *(uint8_t*)0x20000293 = 0; *(uint8_t*)0x20000294 = 0; *(uint8_t*)0x20000295 = 0; *(uint8_t*)0x20000296 = 0; *(uint8_t*)0x20000297 = 0xaa; *(uint32_t*)0x20000298 = 0; syscall(__NR_sendto, r[0], 0x200001c0, 0, 0, 0x20000280, 0x1c); memcpy((void*)0x20000180, "memory.events", 14); res = syscall(__NR_openat, 0xffffff9c, 0x20000180, 0x26e1, 0); if (res != -1) r[2] = res; *(uint32_t*)0x20000000 = 0x58; *(uint32_t*)0x20000004 = 0; *(uint32_t*)0x20000008 = 0; *(uint32_t*)0x2000000c = 0; *(uint32_t*)0x20000010 = 0; *(uint64_t*)0x20000018 = 0; syscall(__NR_ioctl, r[2], 0x401c5820, 0x20000000); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { use_temporary_dir(); do_sandbox_none(); } } sleep(1000000); return 0; }