// https://syzkaller.appspot.com/bug?id=f3ddd7724674ca780476e946287afab776e7c590
// 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 <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.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>
#include <linux/sched.h>

#ifndef __NR_bpf
#define __NR_bpf 321
#endif
#ifndef __NR_clone3
#define __NR_clone3 435
#endif
#ifndef __NR_sched_setattr
#define __NR_sched_setattr 314
#endif

static unsigned long long procid;

static __thread int clone_ongoing;
static __thread int skip_segv;
static __thread jmp_buf segv_env;

static void segv_handler(int sig, siginfo_t* info, void* ctx)
{
  if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) {
    exit(sig);
  }
  uintptr_t addr = (uintptr_t)info->si_addr;
  const uintptr_t prog_start = 1 << 20;
  const uintptr_t prog_end = 100 << 20;
  int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0;
  int valid = addr < prog_start || addr > prog_end;
  if (skip && valid) {
    _longjmp(segv_env, 1);
  }
  exit(sig);
}

static void install_segv_handler(void)
{
  struct sigaction sa;
  memset(&sa, 0, sizeof(sa));
  sa.sa_handler = SIG_IGN;
  syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8);
  syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8);
  memset(&sa, 0, sizeof(sa));
  sa.sa_sigaction = segv_handler;
  sa.sa_flags = SA_NODEFER | SA_SIGINFO;
  sigaction(SIGSEGV, &sa, NULL);
  sigaction(SIGBUS, &sa, NULL);
}

#define NONFAILING(...)                                                        \
  ({                                                                           \
    int ok = 1;                                                                \
    __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    if (_setjmp(segv_env) == 0) {                                              \
      __VA_ARGS__;                                                             \
    } else                                                                     \
      ok = 0;                                                                  \
    __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    ok;                                                                        \
  })

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 use_temporary_dir(void)
{
  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 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;
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir)
{
  int iter = 0;
  DIR* dp = 0;
retry:
  while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
  }
  dp = opendir(dir);
  if (dp == NULL) {
    if (errno == EMFILE) {
      exit(1);
    }
    exit(1);
  }
  struct dirent* ep = 0;
  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 | UMOUNT_NOFOLLOW) == 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 == EPERM) {
        int fd = open(filename, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
          }
          close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno != EBUSY || i > 100)
        exit(1);
      if (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW))
        exit(1);
    }
  }
  closedir(dp);
  for (int i = 0;; i++) {
    if (rmdir(dir) == 0)
      break;
    if (i < 100) {
      if (errno == EPERM) {
        int fd = open(dir, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
          }
          close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno == EBUSY) {
        if (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW))
          exit(1);
        continue;
      }
      if (errno == ENOTEMPTY) {
        if (iter < 100) {
          iter++;
          goto retry;
        }
      }
    }
    exit(1);
  }
}

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");
  if (symlink("/dev/binderfs", "./binderfs")) {
  }
}

static void setup_sysctl()
{
  char mypid[32];
  snprintf(mypid, sizeof(mypid), "%d", getpid());
  struct {
    const char* name;
    const char* data;
  } files[] = {
      {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"},
      {"/proc/sys/kernel/hung_task_check_interval_secs", "20"},
      {"/proc/sys/net/core/bpf_jit_kallsyms", "1"},
      {"/proc/sys/net/core/bpf_jit_harden", "0"},
      {"/proc/sys/kernel/kptr_restrict", "0"},
      {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"},
      {"/proc/sys/fs/mount-max", "100"},
      {"/proc/sys/vm/oom_dump_tasks", "0"},
      {"/proc/sys/debug/exception-trace", "0"},
      {"/proc/sys/kernel/printk", "7 4 1 3"},
      {"/proc/sys/kernel/keys/gc_delay", "1"},
      {"/proc/sys/vm/oom_kill_allocating_task", "1"},
      {"/proc/sys/kernel/ctrl-alt-del", "0"},
      {"/proc/sys/kernel/cad_pid", mypid},
  };
  for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].name, files[i].data))
      printf("write to %s failed: %s\n", files[i].name, strerror(errno));
  }
}

#define USLEEP_FORKED_CHILD (3 * 50 * 1000)

static long handle_clone_ret(long ret)
{
  if (ret != 0) {
    __atomic_store_n(&clone_ongoing, 0, __ATOMIC_RELAXED);
    return ret;
  }
  usleep(USLEEP_FORKED_CHILD);
  syscall(__NR_exit, 0);
  while (1) {
  }
}

#define MAX_CLONE_ARGS_BYTES 256
static long syz_clone3(volatile long a0, volatile long a1)
{
  unsigned long copy_size = a1;
  if (copy_size < sizeof(uint64_t) || copy_size > MAX_CLONE_ARGS_BYTES)
    return -1;
  char clone_args[MAX_CLONE_ARGS_BYTES];
  memcpy(&clone_args, (void*)a0, copy_size);
  uint64_t* flags = (uint64_t*)&clone_args;
  *flags &= ~CLONE_VM;
  __atomic_store_n(&clone_ongoing, 1, __ATOMIC_RELAXED);
  return handle_clone_ret((long)syscall(__NR_clone3, &clone_args, copy_size));
}

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 < 14; 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 + (call == 12 ? 500 : 0));
      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++) {
    char cwdbuf[32];
    sprintf(cwdbuf, "./%d", iter);
    if (mkdir(cwdbuf, 0777))
      exit(1);
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      if (chdir(cwdbuf))
        exit(1);
      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 < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
    remove_dir(cwdbuf);
  }
}

uint64_t r[3] = {0x0, 0xffffffffffffffff, 0xffffffffffffffff};

void execute_call(int call)
{
  intptr_t res = 0;
  switch (call) {
  case 0:
    NONFAILING(*(uint64_t*)0x20000140 = 8);
    NONFAILING(*(uint64_t*)0x20000148 = 0x8b);
    syscall(__NR_prlimit64, 0, 0xeul, 0x20000140ul, 0ul);
    break;
  case 1:
    NONFAILING(*(uint32_t*)0x20000080 = 6);
    syscall(__NR_sched_setscheduler, 0, 2ul, 0x20000080ul);
    break;
  case 2:
    NONFAILING(*(uint64_t*)0x200000c0 = 5);
    syscall(__NR_sched_setaffinity, 0, 8ul, 0x200000c0ul);
    break;
  case 3:
    res = syscall(__NR_getpid);
    if (res != -1)
      r[0] = res;
    break;
  case 4:
    NONFAILING(*(uint32_t*)0x20001700 = 4);
    syscall(__NR_sched_setscheduler, r[0], 1ul, 0x20001700ul);
    break;
  case 5:
    res = syscall(__NR_socketpair, 1ul, 2ul, 0, 0x20000200ul);
    if (res != -1) {
      NONFAILING(r[1] = *(uint32_t*)0x20000200);
      NONFAILING(r[2] = *(uint32_t*)0x20000204);
    }
    break;
  case 6:
    syscall(__NR_getpid);
    break;
  case 7:
    NONFAILING(*(uint16_t*)0x2057eff8 = 0);
    NONFAILING(*(uint8_t*)0x2057effa = 0);
    NONFAILING(*(uint32_t*)0x2057effc = 0);
    syscall(__NR_connect, r[1], 0x2057eff8ul, 0x6eul);
    break;
  case 8:
    syscall(__NR_sendmmsg, r[2], 0x200bd000ul, 0x318ul, 0ul);
    break;
  case 9:
    syscall(__NR_recvmmsg, r[1], 0x200000c0ul, 0x10106ul, 2ul, 0ul);
    break;
  case 10:
    NONFAILING(*(uint32_t*)0x20000040 = 0x38);
    NONFAILING(*(uint32_t*)0x20000044 = 0);
    NONFAILING(*(uint64_t*)0x20000048 = 0);
    NONFAILING(*(uint32_t*)0x20000050 = 0);
    NONFAILING(*(uint32_t*)0x20000054 = 0);
    NONFAILING(*(uint64_t*)0x20000058 = 0);
    NONFAILING(*(uint64_t*)0x20000060 = 0);
    NONFAILING(*(uint64_t*)0x20000068 = 0);
    NONFAILING(*(uint32_t*)0x20000070 = 0);
    NONFAILING(*(uint32_t*)0x20000074 = 0);
    syscall(__NR_sched_setattr, 0, 0x20000040ul, 0ul);
    break;
  case 11:
    NONFAILING(*(uint64_t*)0x20000a00 = 0x40b86000);
    NONFAILING(*(uint64_t*)0x20000a08 = 0);
    NONFAILING(*(uint64_t*)0x20000a10 = 0);
    NONFAILING(*(uint64_t*)0x20000a18 = 0);
    NONFAILING(*(uint32_t*)0x20000a20 = 0x1d);
    NONFAILING(*(uint64_t*)0x20000a28 = 0);
    NONFAILING(*(uint64_t*)0x20000a30 = 0);
    NONFAILING(*(uint64_t*)0x20000a38 = 0);
    NONFAILING(*(uint64_t*)0x20000a40 = 0);
    NONFAILING(*(uint64_t*)0x20000a48 = 0);
    NONFAILING(*(uint32_t*)0x20000a50 = -1);
    NONFAILING(syz_clone3(0x20000a00, 0x58));
    break;
  case 12:
    NONFAILING(*(uint32_t*)0x20000440 = 5);
    NONFAILING(*(uint32_t*)0x20000444 = 0xa);
    NONFAILING(*(uint64_t*)0x20000448 = 0);
    NONFAILING(*(uint64_t*)0x20000450 = 0x20000000);
    NONFAILING(memcpy((void*)0x20000000, "GPL\000", 4));
    NONFAILING(*(uint32_t*)0x20000458 = 4);
    NONFAILING(*(uint32_t*)0x2000045c = 0xee);
    NONFAILING(*(uint64_t*)0x20000460 = 0x20000340);
    NONFAILING(*(uint32_t*)0x20000468 = 0);
    NONFAILING(*(uint32_t*)0x2000046c = 8);
    NONFAILING(memset((void*)0x20000470, 0, 16));
    NONFAILING(*(uint32_t*)0x20000480 = 0);
    NONFAILING(*(uint32_t*)0x20000484 = 0);
    NONFAILING(*(uint32_t*)0x20000488 = -1);
    NONFAILING(*(uint32_t*)0x2000048c = 8);
    NONFAILING(*(uint64_t*)0x20000490 = 0);
    NONFAILING(*(uint32_t*)0x20000498 = 0);
    NONFAILING(*(uint32_t*)0x2000049c = 0x10);
    NONFAILING(*(uint64_t*)0x200004a0 = 0);
    NONFAILING(*(uint32_t*)0x200004a8 = 0);
    NONFAILING(*(uint32_t*)0x200004ac = 0);
    NONFAILING(*(uint32_t*)0x200004b0 = 0);
    NONFAILING(*(uint32_t*)0x200004b4 = 0);
    NONFAILING(*(uint64_t*)0x200004b8 = 0);
    syscall(__NR_bpf, 5ul, 0x20000440ul, 0x80ul);
    break;
  case 13:
    NONFAILING(*(uint32_t*)0x20000000 = 6);
    NONFAILING(*(uint32_t*)0x20000004 = 4);
    NONFAILING(*(uint32_t*)0x20000008 = 0x7fff);
    NONFAILING(*(uint32_t*)0x2000000c = 0x3f);
    NONFAILING(*(uint32_t*)0x20000010 = 0);
    NONFAILING(*(uint32_t*)0x20000014 = 1);
    NONFAILING(*(uint32_t*)0x20000018 = 0);
    NONFAILING(memset((void*)0x2000001c, 0, 16));
    NONFAILING(*(uint32_t*)0x2000002c = 0);
    NONFAILING(*(uint32_t*)0x20000030 = -1);
    NONFAILING(*(uint32_t*)0x20000034 = 0);
    NONFAILING(*(uint32_t*)0x20000038 = 0);
    NONFAILING(*(uint32_t*)0x2000003c = 0);
    NONFAILING(*(uint64_t*)0x20000040 = 0);
    syscall(__NR_bpf, 0ul, 0x20000000ul, 0x48ul);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  setup_sysctl();
  install_segv_handler();
  for (procid = 0; procid < 6; procid++) {
    if (fork() == 0) {
      use_temporary_dir();
      loop();
    }
  }
  sleep(1000000);
  return 0;
}