// https://syzkaller.appspot.com/bug?id=96955a172bfcf0cfb12480821b2fff1ad2f72296
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <sched.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#include <linux/capability.h>
#include <linux/futex.h>

unsigned long long procid;

static void sleep_ms(uint64_t ms)
{
  usleep(ms * 1000);
}

static uint64_t current_time_ms(void)
{
  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 thread_start(void* (*fn)(void*), void* arg)
{
  pthread_t th;
  pthread_attr_t attr;
  pthread_attr_init(&attr);
  pthread_attr_setstacksize(&attr, 128 << 10);
  int i;
  for (i = 0; i < 100; i++) {
    if (pthread_create(&th, &attr, fn, arg) == 0) {
      pthread_attr_destroy(&attr);
      return;
    }
    if (errno == EAGAIN) {
      usleep(50);
      continue;
    }
    break;
  }
  exit(1);
}

typedef struct {
  int state;
} event_t;

static void event_init(event_t* ev)
{
  ev->state = 0;
}

static void event_reset(event_t* ev)
{
  ev->state = 0;
}

static void event_set(event_t* ev)
{
  if (ev->state)
    exit(1);
  __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE);
  syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG);
}

static void event_wait(event_t* ev)
{
  while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
    syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0);
}

static int event_isset(event_t* ev)
{
  return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE);
}

static int event_timedwait(event_t* ev, uint64_t timeout)
{
  uint64_t start = current_time_ms();
  uint64_t now = start;
  for (;;) {
    uint64_t remain = timeout - (now - start);
    struct timespec ts;
    ts.tv_sec = remain / 1000;
    ts.tv_nsec = (remain % 1000) * 1000 * 1000;
    syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts);
    if (__atomic_load_n(&ev->state, __ATOMIC_RELAXED))
      return 1;
    now = current_time_ms();
    if (now - start > timeout)
      return 0;
  }
}

static bool write_file(const char* file, const char* what, ...)
{
  char buf[1024];
  va_list args;
  va_start(args, what);
  vsnprintf(buf, sizeof(buf), what, args);
  va_end(args);
  buf[sizeof(buf) - 1] = 0;
  int len = strlen(buf);
  int fd = open(file, O_WRONLY | O_CLOEXEC);
  if (fd == -1)
    return false;
  if (write(fd, buf, len) != len) {
    int err = errno;
    close(fd);
    errno = err;
    return false;
  }
  close(fd);
  return true;
}

static void setup_common()
{
  if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
  }
}

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 = (200 << 20);
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 32 << 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)) {
  }
  typedef struct {
    const char* name;
    const char* value;
  } sysctl_t;
  static const sysctl_t sysctls[] = {
      {"/proc/sys/kernel/shmmax", "16777216"},
      {"/proc/sys/kernel/shmall", "536870912"},
      {"/proc/sys/kernel/shmmni", "1024"},
      {"/proc/sys/kernel/msgmax", "8192"},
      {"/proc/sys/kernel/msgmni", "1024"},
      {"/proc/sys/kernel/msgmnb", "1024"},
      {"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
  };
  unsigned i;
  for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
    write_file(sysctls[i].name, sysctls[i].value);
}

int wait_for_loop(int pid)
{
  if (pid < 0)
    exit(1);
  int status = 0;
  while (waitpid(-1, &status, __WALL) != pid) {
  }
  return WEXITSTATUS(status);
}

static void drop_caps(void)
{
  struct __user_cap_header_struct cap_hdr = {};
  struct __user_cap_data_struct cap_data[2] = {};
  cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
  cap_hdr.pid = getpid();
  if (syscall(SYS_capget, &cap_hdr, &cap_data))
    exit(1);
  const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
  cap_data[0].effective &= ~drop;
  cap_data[0].permitted &= ~drop;
  cap_data[0].inheritable &= ~drop;
  if (syscall(SYS_capset, &cap_hdr, &cap_data))
    exit(1);
}

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();
  drop_caps();
  if (unshare(CLONE_NEWNET)) {
  }
  loop();
  exit(1);
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  int i;
  for (i = 0; i < 100; i++) {
    if (waitpid(-1, status, WNOHANG | __WALL) == pid)
      return;
    usleep(1000);
  }
  DIR* dir = opendir("/sys/fs/fuse/connections");
  if (dir) {
    for (;;) {
      struct dirent* ent = readdir(dir);
      if (!ent)
        break;
      if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
        continue;
      char abort[300];
      snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
               ent->d_name);
      int fd = open(abort, O_WRONLY);
      if (fd == -1) {
        continue;
      }
      if (write(fd, abort, 1) < 0) {
      }
      close(fd);
    }
    closedir(dir);
  } else {
  }
  while (waitpid(-1, status, __WALL) != pid) {
  }
}

static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  write_file("/proc/self/oom_score_adj", "1000");
}

static void close_fds()
{
  int fd;
  for (fd = 3; fd < 30; fd++)
    close(fd);
}

struct thread_t {
  int created, call;
  event_t ready, done;
};

static struct thread_t threads[16];
static void execute_call(int call);
static int running;

static void* thr(void* arg)
{
  struct thread_t* th = (struct thread_t*)arg;
  for (;;) {
    event_wait(&th->ready);
    event_reset(&th->ready);
    execute_call(th->call);
    __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
    event_set(&th->done);
  }
  return 0;
}

static void execute_one(void)
{
  int i, call, thread;
  for (call = 0; call < 3; call++) {
    for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0]));
         thread++) {
      struct thread_t* th = &threads[thread];
      if (!th->created) {
        th->created = 1;
        event_init(&th->ready);
        event_init(&th->done);
        event_set(&th->done);
        thread_start(thr, th);
      }
      if (!event_isset(&th->done))
        continue;
      event_reset(&th->done);
      th->call = call;
      __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
      event_set(&th->ready);
      event_timedwait(&th->done, 45);
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
  close_fds();
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter;
  for (iter = 0;; iter++) {
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      setup_test();
      execute_one();
      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_and_wait(pid, &status);
      break;
    }
  }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_call(int call)
{
  intptr_t res;
  switch (call) {
  case 0:
    res = syscall(__NR_socket, 0x2000000000000021, 2, 2);
    if (res != -1)
      r[0] = res;
    break;
  case 1:
    *(uint16_t*)0x20000180 = 0x21;
    *(uint16_t*)0x20000182 = 0;
    *(uint16_t*)0x20000184 = 2;
    *(uint16_t*)0x20000186 = 0x10;
    *(uint16_t*)0x20000188 = 2;
    *(uint16_t*)0x2000018a = htobe16(0);
    *(uint8_t*)0x2000018c = 0xac;
    *(uint8_t*)0x2000018d = 0x14;
    *(uint8_t*)0x2000018e = 0x14;
    *(uint8_t*)0x2000018f = 0;
    syscall(__NR_connect, r[0], 0x20000180, 0x24);
    break;
  case 2:
    *(uint64_t*)0x20005c00 = 0;
    *(uint32_t*)0x20005c08 = 0;
    *(uint64_t*)0x20005c10 = 0;
    *(uint64_t*)0x20005c18 = 0;
    *(uint64_t*)0x20005c20 = 0x200001c0;
    memcpy((void*)0x200001c0,
           "\x18\x00\x00\x00\x00\x00\x00\x00\x10\x01\x00\x00\x01\x00\x00\x00"
           "\x77\x00\x00\x00\x00\x00\x00\x00\xf4\x1b\x25\xe4\x16\xd5\x89\x37"
           "\xe7\xe8\x99\xe0\x52\x48\x43\xc9\x57\x7f\x89\xf7\x1e\xbd\xdf\x07"
           "\x77\x98\xb4\x7a\xb4\xa7\x69\x07\x47\x7a\x20\x95\x22\xad\xca\x7e"
           "\x54\x54\xb7\xde\xc9\xd9\xa6\x73\x05\xc0\x4a\x8c\xcf\xfc\xa5\x6c"
           "\xcb\xca\xbf\xb2\x5c\xc9\x46\x28\x34\x8a\x24\x59\x3c\x6f\xbd\xf2"
           "\x00\x79\x6a\x8f\xd2\x17\x36\x7c\x01\x7f\x76\xf1\x31\xc8\x69\x3a"
           "\xc4\x3b\x77\x47\x1b\xe9\x14\x70\x7d\x2c\x35\x45\xb8\x12\xf7\xf5"
           "\x8f\x43\x67\x06\xf1\x7b\x26\xae\x32\x08\xe5\x80\x9f\x51\x52\x8f"
           "\x24\x36\x61\x0c\x52\xb7\x24\x99\x31\x41\xa5\xcb\x7a\x0a\x9c\x50"
           "\xca\x0a\x16\x78\x7a\x4d\x0c\x82\xe2\xd9\x82\x92\x19\xe3\xd9\x81"
           "\xd1\x96\xf1\xb7\x25\x6c\x49\xaa\xc9\x6b\x00\x00\x00\x00\x21\x50"
           "\xa4\x05\x8a\x8e\x43\x47\xe1\x3f\x94\xbe\x6d\x87\xfc\x02\x42\xaf"
           "\x16\x38\x0c\x36\x42\x44\x85\xf1\x59\x6c\x19\xb6\x58\xa3\xfc\x3b"
           "\xee\x2b\x53\x44\xa0\x3e\x56\x4d\xb3\x90\x7e\x44\x31\xd8\xb0\x2c"
           "\xde\xe6\x2f\x75\xf3\xc0\x11\xb6\xbc\x17\xb2\xb8\x18\x2d\x18\xa5"
           "\x8c\xf7\x50\xd9\xe2\xce\x87\x4b\x29\xb6\x50\x20\xae\x14\x80\x15"
           "\x5a\x75\x36\xa2\x26\x6e\xe6\x6e\xfa\x3e\x1d\x2f\x93\x77\x85\x00"
           "\x71\xc0\xe4\x9e\x01\xc7\x52\xf4\x81\x54\xef\x17\xf0\xd8\x7d\x84"
           "\x1f\xa3\x39\xb7\x95\x4e\x2c\xee\x64\x87\x11\x14\xab\x3f\xb3\xc6"
           "\xa9\x61\xc1\xc8\x7d\x97\xfb\x57\x8b\x6d\x87\xcc\x36\xb7\x99\x95"
           "\x2a\xc1\xa0\xab\xa7\xe9\x8d\x36\xce\x5a\x5b\x4b\xa9\x59\x6a\x0e"
           "\xd6\x29\x85\x48\x0b\x8d\xaf\xd9\xa7\x95\x10\xe2\x26\x29\xf8\xb7"
           "\x7a\x02\x8d\x9c\x79\x90\x1e\xae\xba\xe1\x71\x26\x35",
           381);
    *(uint64_t*)0x20005c28 = 0x18;
    *(uint32_t*)0x20005c30 = 0;
    *(uint32_t*)0x20005c38 = 0;
    syscall(__NR_sendmmsg, r[0], 0x20005c00, 1, 0);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 6; procid++) {
    if (fork() == 0) {
      do_sandbox_none();
    }
  }
  sleep(1000000);
  return 0;
}