// https://syzkaller.appspot.com/bug?id=a1954eed3adfde914df9a0a2d0b7d1ecb876072f
// 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 <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>

#include <linux/futex.h>

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 = 0;
  for (; 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, 1000000);
}

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_ACQUIRE))
      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 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");
}

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)
{
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  int i, call, thread;
  for (call = 0; call < 4; 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, 50);
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
}

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[1] = {0xffffffffffffffff};

void execute_call(int call)
{
  intptr_t res = 0;
  switch (call) {
  case 0:
    //  mkdirat arguments: [
    //    fd: fd_dir (resource)
    //    path: ptr[in, buffer] {
    //      buffer: {2e 2f 73 79 73 00} (length 0x6)
    //    }
    //    mode: open_mode = 0x1ff (8 bytes)
    //  ]
    memcpy((void*)0x200000000000, "./sys\000", 6);
    syscall(
        __NR_mkdirat, /*fd=*/0xffffff9c, /*path=*/0x200000000000ul,
        /*mode=S_IXOTH|S_IWOTH|S_IROTH|S_IXGRP|S_IWGRP|S_IRGRP|S_IXUSR|S_IWUSR|0x100*/
        0x1fful);
    break;
  case 1:
    //  mount arguments: [
    //    src: nil
    //    dst: ptr[in, buffer] {
    //      buffer: {2e 2f 73 79 73 00} (length 0x6)
    //    }
    //    type: ptr[in, buffer] {
    //      buffer: {73 79 73 66 73 00} (length 0x6)
    //    }
    //    flags: mount_flags = 0x0 (8 bytes)
    //    data: nil
    //  ]
    memcpy((void*)0x200000000000, "./sys\000", 6);
    memcpy((void*)0x200000000040, "sysfs\000", 6);
    syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x200000000000ul,
            /*type=*/0x200000000040ul, /*flags=*/0ul, /*data=*/0ul);
    break;
  case 2:
    //  openat arguments: [
    //    fd: fd_dir (resource)
    //    file: ptr[in, buffer] {
    //      buffer: {2e 2f 73 79 73 2f 62 75 73 2f 70 63 69 2f 64 65 76 69 63 65
    //      73 2f 30 30 30 30 3a 30 30 3a 30 33 2e 30 2f 63 6f 6e 66 69 67 00}
    //      (length 0x2a)
    //    }
    //    flags: open_flags = 0x2 (4 bytes)
    //    mode: open_mode = 0x0 (2 bytes)
    //  ]
    //  returns fd
    memcpy((void*)0x200000000080,
           "./sys/bus/pci/devices/0000:00:03.0/config\000", 42);
    res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x200000000080ul,
                  /*flags=O_RDWR*/ 2, /*mode=*/0);
    if (res != -1)
      r[0] = res;
    break;
  case 3:
    //  pwrite64 arguments: [
    //    fd: fd (resource)
    //    buf: ptr[in, buffer] {
    //      buffer: {02 a2 51 6c 4e c2 16 bf 83 a6 7d 78 e5 14 89 3e 2f 78 ed 88
    //      c0 c4 b0 e4 0f f0 2d ba f1 0d 2d 71 8b e6 41 48 d0 ee 46 9a 18 c9 63
    //      82 fd 5c 12 96 b3 1e 4b e6 e7 76 2e 48 68 c5 13 1f 56 e0 44 8c 3a 36
    //      e3 64 78 3b 3c ca cd 87 c2 2d 18 ea 3f 83 10 19 e4 2d d9 7f 59 b0 e8
    //      dd 78 98 3e 13 30 0f fe 77 48 93 78 f0 c0 49 fb ed 30 77 d0 7d ed c7
    //      c2 6a 8f 32 40 9b 7b c6 7b 3f 6a e9 46 41 bb 89 06 bd 83 11 8c ad 5b
    //      70 fd 60 28 a1 b6 e3 eb 23 18 ac f4 87 90 78 dc 94 5b 75 75 8f 8a 7d
    //      85 28 3f 0f c9 ac 0b 17 b1 41 f9 26 62 e9 e2 11 7c 11 93 1d fa 31
    //      b3} (length 0xb5)
    //    }
    //    count: len = 0xb5 (8 bytes)
    //    pos: intptr = 0x24 (8 bytes)
    //  ]
    memcpy(
        (void*)0x200000000400,
        "\x02\xa2\x51\x6c\x4e\xc2\x16\xbf\x83\xa6\x7d\x78\xe5\x14\x89\x3e\x2f"
        "\x78\xed\x88\xc0\xc4\xb0\xe4\x0f\xf0\x2d\xba\xf1\x0d\x2d\x71\x8b\xe6"
        "\x41\x48\xd0\xee\x46\x9a\x18\xc9\x63\x82\xfd\x5c\x12\x96\xb3\x1e\x4b"
        "\xe6\xe7\x76\x2e\x48\x68\xc5\x13\x1f\x56\xe0\x44\x8c\x3a\x36\xe3\x64"
        "\x78\x3b\x3c\xca\xcd\x87\xc2\x2d\x18\xea\x3f\x83\x10\x19\xe4\x2d\xd9"
        "\x7f\x59\xb0\xe8\xdd\x78\x98\x3e\x13\x30\x0f\xfe\x77\x48\x93\x78\xf0"
        "\xc0\x49\xfb\xed\x30\x77\xd0\x7d\xed\xc7\xc2\x6a\x8f\x32\x40\x9b\x7b"
        "\xc6\x7b\x3f\x6a\xe9\x46\x41\xbb\x89\x06\xbd\x83\x11\x8c\xad\x5b\x70"
        "\xfd\x60\x28\xa1\xb6\xe3\xeb\x23\x18\xac\xf4\x87\x90\x78\xdc\x94\x5b"
        "\x75\x75\x8f\x8a\x7d\x85\x28\x3f\x0f\xc9\xac\x0b\x17\xb1\x41\xf9\x26"
        "\x62\xe9\xe2\x11\x7c\x11\x93\x1d\xfa\x31\xb3",
        181);
    syscall(__NR_pwrite64, /*fd=*/r[0], /*buf=*/0x200000000400ul,
            /*count=*/0xb5ul, /*pos=*/0x24ul);
    break;
  }
}
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;
  loop();
  return 0;
}