// https://syzkaller.appspot.com/bug?id=0f30b5bd93279794207d00165448beb9e1318cd6
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

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

#ifndef __NR_fchdir
#define __NR_fchdir 50
#endif
#ifndef __NR_gettid
#define __NR_gettid 178
#endif
#ifndef __NR_mmap
#define __NR_mmap 222
#endif
#ifndef __NR_mount
#define __NR_mount 40
#endif
#ifndef __NR_openat
#define __NR_openat 56
#endif
#ifndef __NR_rt_sigreturn
#define __NR_rt_sigreturn 139
#endif
#ifndef __NR_sendto
#define __NR_sendto 206
#endif
#ifndef __NR_socket
#define __NR_socket 198
#endif
#ifndef __NR_timer_settime
#define __NR_timer_settime 110
#endif

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 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 long syz_open_procfs(volatile long a0, volatile long a1)
{
  char buf[128];
  memset(buf, 0, sizeof(buf));
  if (a0 == 0) {
    snprintf(buf, sizeof(buf), "/proc/self/%s", (char*)a1);
  } else if (a0 == -1) {
    snprintf(buf, sizeof(buf), "/proc/thread-self/%s", (char*)a1);
  } else {
    snprintf(buf, sizeof(buf), "/proc/self/task/%d/%s", (int)a0, (char*)a1);
  }
  int fd = open(buf, O_RDWR);
  if (fd == -1)
    fd = open(buf, O_RDONLY);
  return fd;
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  for (int 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 execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter = 0;
  for (;; 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 (;;) {
      sleep_ms(10);
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
  }
}

uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff};

void execute_one(void)
{
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  syscall(__NR_gettid);
  res = syscall(__NR_socket, /*domain=*/2ul, /*type=*/2ul, /*proto=*/0);
  if (res != -1)
    r[0] = res;
  syscall(__NR_sendto, /*fd=*/r[0], /*buf=*/0ul, /*len=*/0ul,
          /*f=MSG_PROBE|MSG_EOR*/ 0x90ul, /*addr=*/0ul, /*addrlen=*/0ul);
  memcpy((void*)0x20000040, "ns/user\000", 8);
  syz_open_procfs(/*pid=*/0, /*file=*/0x20000040);
  memcpy((void*)0x20000200, "/proc/self\000", 11);
  res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000200ul,
                /*flags=*/0, /*mode=*/0);
  if (res != -1)
    r[1] = res;
  syscall(__NR_fchdir, /*fd=*/r[1]);
  memcpy((void*)0x20000000, "ns/net\000", 7);
  syz_open_procfs(/*pid=*/0, /*file=*/0x20000000);
  memcpy((void*)0x20000080, "./cgroup\000", 9);
  syscall(__NR_mount, /*src=*/0x20000000ul, /*dst=*/0x20000080ul, /*type=*/0ul,
          /*flags=MS_RDONLY|MS_BIND*/ 0x1001ul, /*data=*/0ul);
  memcpy((void*)0x20000140, "./cgroup\000", 9);
  syscall(
      __NR_mount, /*src=*/0ul, /*dst=*/0x20000140ul, /*type=*/0ul,
      /*flags=MS_I_VERSION|MS_SHARED|MS_REC|MS_SYNCHRONOUS|MS_SILENT|MS_REMOUNT|0x1*/
      0x90c031ul, /*opts=*/0ul);
  memcpy((void*)0x200006c0, "./cgroup\000", 9);
  syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*dir=*/0x200006c0ul,
          /*flags=O_TRUNC|O_EXCL|O_CLOEXEC|FASYNC|O_RDWR*/ 0x82282,
          /*mode=S_IXOTH*/ 1);
  syscall(__NR_rt_sigreturn);
  syscall(__NR_timer_settime, /*timerid=*/0, /*flags=*/0ul, /*new=*/0ul,
          /*old=*/0ul);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  loop();
  return 0;
}