// https://syzkaller.appspot.com/bug?id=d2c2513590f46343d11e6ec071d782edc790e01c
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.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>

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);
}

#define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off))
#define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len)               \
  *(type*)(addr) =                                                             \
      htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) |           \
            (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len))))

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;
  const int umount_flags = MNT_FORCE | UMOUNT_NOFOLLOW;

retry:
  while (umount2(dir, umount_flags) == 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, umount_flags) == 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, umount_flags))
        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, umount_flags))
          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()
{
  int cad_pid = fork();
  if (cad_pid < 0)
    exit(1);
  if (cad_pid == 0) {
    for (;;)
      sleep(100);
  }
  char tmppid[32];
  snprintf(tmppid, sizeof(tmppid), "%d", cad_pid);
  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", tmppid},
  };
  for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].name, files[i].data)) {
    }
  }
  kill(cad_pid, SIGKILL);
  while (waitpid(cad_pid, NULL, 0) != cad_pid)
    ;
}

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 (;;) {
      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;
    }
    remove_dir(cwdbuf);
  }
}

void execute_one(void)
{
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  NONFAILING(*(uint32_t*)0x20000000 = 1);
  NONFAILING(*(uint32_t*)0x20000004 = 0x80);
  NONFAILING(*(uint8_t*)0x20000008 = 3);
  NONFAILING(*(uint8_t*)0x20000009 = 0);
  NONFAILING(*(uint8_t*)0x2000000a = 0);
  NONFAILING(*(uint8_t*)0x2000000b = 0);
  NONFAILING(*(uint32_t*)0x2000000c = 0);
  NONFAILING(*(uint64_t*)0x20000010 = 0x20);
  NONFAILING(*(uint64_t*)0x20000018 = 0x12506);
  NONFAILING(*(uint64_t*)0x20000020 = 0);
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 0, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 1, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 2, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 3, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 4, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 5, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 6, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 7, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 8, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 9, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 10, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 11, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 12, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 13, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 14, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 15, 2));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 17, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 18, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 19, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 20, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 21, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 22, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 23, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 24, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 25, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 26, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 27, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 28, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 29, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 30, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 31, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 32, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 33, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 34, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 35, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 1, 36, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 1, 37, 1));
  NONFAILING(STORE_BY_BITMASK(uint64_t, , 0x20000028, 0, 38, 26));
  NONFAILING(*(uint32_t*)0x20000030 = 0);
  NONFAILING(*(uint32_t*)0x20000034 = 0);
  NONFAILING(*(uint64_t*)0x20000038 = 0);
  NONFAILING(*(uint64_t*)0x20000040 = 8);
  NONFAILING(*(uint64_t*)0x20000048 = 0x7602);
  NONFAILING(*(uint64_t*)0x20000050 = 0);
  NONFAILING(*(uint32_t*)0x20000058 = 0);
  NONFAILING(*(uint32_t*)0x2000005c = 0);
  NONFAILING(*(uint64_t*)0x20000060 = 0);
  NONFAILING(*(uint32_t*)0x20000068 = 0);
  NONFAILING(*(uint16_t*)0x2000006c = 0);
  NONFAILING(*(uint16_t*)0x2000006e = 0);
  NONFAILING(*(uint32_t*)0x20000070 = 0);
  NONFAILING(*(uint32_t*)0x20000074 = 0);
  NONFAILING(*(uint64_t*)0x20000078 = 0);
  syscall(__NR_perf_event_open, /*attr=*/0x20000000ul, /*pid=*/0, /*cpu=*/-1,
          /*group=*/-1, /*flags=*/0ul);
  syscall(__NR_close, /*fd=*/3);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-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=*/-1,
          /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  setup_sysctl();
  const char* reason;
  (void)reason;
  install_segv_handler();
  use_temporary_dir();
  loop();
  return 0;
}