// https://syzkaller.appspot.com/bug?id=40fb6ad50e598d93ab3aa3b2428836ff84a2f591
// 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/mount.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>

static 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 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 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)) {
  }
  //  mkdirat arguments: [
  //    fd: fd_dir (resource)
  //    path: ptr[in, buffer] {
  //      buffer: {2e 2f 6e 66 73 64 00} (length 0x7)
  //    }
  //    mode: open_mode = 0x1ff (8 bytes)
  //  ]
  memcpy((void*)0x200000000180, "./nfsd\000", 7);
  syscall(
      __NR_mkdirat, /*fd=*/0xffffff9c, /*path=*/0x200000000180ul,
      /*mode=S_IXOTH|S_IWOTH|S_IROTH|S_IXGRP|S_IWGRP|S_IRGRP|S_IXUSR|S_IWUSR|0x100*/
      0x1fful);
  //  mount arguments: [
  //    src: nil
  //    dst: ptr[in, buffer] {
  //      buffer: {2e 2f 6e 66 73 64 00} (length 0x7)
  //    }
  //    type: ptr[in, buffer] {
  //      buffer: {6e 66 73 64 00} (length 0x5)
  //    }
  //    flags: mount_flags = 0x0 (8 bytes)
  //    data: nil
  //  ]
  memcpy((void*)0x200000000200, "./nfsd\000", 7);
  memcpy((void*)0x200000000240, "nfsd\000", 5);
  syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x200000000200ul,
          /*type=*/0x200000000240ul, /*flags=*/0ul, /*data=*/0ul);
  //  openat arguments: [
  //    fd: fd_dir (resource)
  //    file: ptr[in, buffer] {
  //      buffer: {2e 2f 6e 66 73 64 2f 70 6f 72 74 6c 69 73 74 00} (length
  //      0x10)
  //    }
  //    flags: open_flags = 0x1 (4 bytes)
  //    mode: open_mode = 0x0 (2 bytes)
  //  ]
  //  returns fd
  memcpy((void*)0x200000000340, "./nfsd/portlist\000", 16);
  res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x200000000340ul,
                /*flags=O_WRONLY*/ 1, /*mode=*/0);
  if (res != -1)
    r[0] = res;
  //  write arguments: [
  //    fd: fd (resource)
  //    buf: ptr[in, buffer] {
  //      buffer: {34 0a 00} (length 0x3)
  //    }
  //    count: len = 0x2 (8 bytes)
  //  ]
  memcpy((void*)0x200000000380, "4\n\000", 3);
  syscall(__NR_write, /*fd=*/r[0], /*buf=*/0x200000000380ul, /*count=*/2ul);
  //  socket$inet_udp arguments: [
  //    domain: const = 0x2 (8 bytes)
  //    type: const = 0x2 (8 bytes)
  //    proto: const = 0x0 (4 bytes)
  //  ]
  //  returns sock_udp
  res = syscall(__NR_socket, /*domain=*/2ul, /*type=*/2ul, /*proto=*/0);
  if (res != -1)
    r[1] = res;
  //  ioctl$sock_inet_SIOCSIFFLAGS arguments: [
  //    fd: sock (resource)
  //    cmd: const = 0x8914 (4 bytes)
  //    arg: ptr[in, ifreq_dev_t[devnames, flags[ifru_flags, int16]]] {
  //      ifreq_dev_t[devnames, flags[ifru_flags, int16]] {
  //        ifr_ifrn: buffer: {6c 6f 00 00 00 00 00 00 00 00 00 00 00 00 00 00}
  //        (length 0x10) elem: ifru_flags = 0x0 (2 bytes) pad = 0x0 (22 bytes)
  //      }
  //    }
  //  ]
  memcpy((void*)0x200000000040,
         "lo\000\000\000\000\000\000\000\000\000\000\000\000\000\000", 16);
  *(uint16_t*)0x200000000050 = 0;
  syscall(__NR_ioctl, /*fd=*/r[1], /*cmd=*/0x8914, /*arg=*/0x200000000040ul);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000,
          /*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=*/0x200001000000ul, /*len=*/0x1000, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  for (procid = 0; procid < 5; procid++) {
    if (fork() == 0) {
      loop();
    }
  }
  sleep(1000000);
  return 0;
}