// https://syzkaller.appspot.com/bug?id=5012f2049b6bbd556e258fcfc6ba61d2909a51bf
// 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/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 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 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 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);
  }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_one(void)
{
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  //  mknodat$loop arguments: [
  //    dirfd: fd_dir (resource)
  //    file: ptr[in, buffer] {
  //      buffer: {2e 2f 66 69 6c 65 30 00} (length 0x8)
  //    }
  //    mode: mknod_mode = 0x6000 (8 bytes)
  //    dev: proc = 0x1 (4 bytes)
  //  ]
  memcpy((void*)0x200000000040, "./file0\000", 8);
  syscall(__NR_mknodat, /*dirfd=*/0xffffff9c, /*file=*/0x200000000040ul,
          /*mode=S_IFBLK*/ 0x6000ul, /*dev=*/0x701);
  //  openat$fuse arguments: [
  //    fd: const = 0xffffffffffffff9c (8 bytes)
  //    file: ptr[in, buffer] {
  //      buffer: {2f 64 65 76 2f 66 75 73 65 00} (length 0xa)
  //    }
  //    flags: const = 0x2 (4 bytes)
  //    mode: const = 0x0 (2 bytes)
  //  ]
  //  returns fd_fuse
  memcpy((void*)0x200000000280, "/dev/fuse\000", 10);
  res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul,
                /*file=*/0x200000000280ul, /*flags=*/2, /*mode=*/0);
  if (res != -1)
    r[0] = res;
  //  mount$fuse arguments: [
  //    src: const = 0x0 (8 bytes)
  //    dst: ptr[in, buffer] {
  //      buffer: {2e 2f 66 69 6c 65 30 00} (length 0x8)
  //    }
  //    type: ptr[in, buffer] {
  //      buffer: {66 75 73 65 00} (length 0x5)
  //    }
  //    flags: mount_flags = 0x0 (8 bytes)
  //    opts: ptr[inout, array[ANYUNION]] {
  //      array[ANYUNION] {
  //        union ANYUNION {
  //          ANYBLOB: buffer: {66 64 3d} (length 0x3)
  //        }
  //        union ANYUNION {
  //          ANYRESHEX: ANYRES64 (resource)
  //        }
  //        union ANYUNION {
  //          ANYBLOB: buffer: {2c 72 6f 6f 74 6d 6f 64 65 3d 30 30 30 30 30 30
  //          30 30 30 30 30 30 30 30 30 30 30 30 36 30 30 30 30 2c 75 73 65 72
  //          5f 69 64 3d} (length 0x2a)
  //        }
  //        union ANYUNION {
  //          ANYRESDEC: ANYRES64 (resource)
  //        }
  //        union ANYUNION {
  //          ANYBLOB: buffer: {2c 67 72 6f 75 70 5f 69 64 3d} (length 0xa)
  //        }
  //        union ANYUNION {
  //          ANYRESDEC: ANYRES64 (resource)
  //        }
  //      }
  //    }
  //  ]
  memcpy((void*)0x200000000100, "./file0\000", 8);
  memcpy((void*)0x200000000140, "fuse\000", 5);
  memcpy((void*)0x200000000540, "fd=", 3);
  sprintf((char*)0x200000000543, "0x%016llx", (long long)r[0]);
  memcpy((void*)0x200000000555,
         ",rootmode=00000000000000000060000,user_id=", 42);
  sprintf((char*)0x20000000057f, "%020llu", (long long)0);
  memcpy((void*)0x200000000593, ",group_id=", 10);
  sprintf((char*)0x20000000059d, "%020llu", (long long)0);
  syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x200000000100ul,
          /*type=*/0x200000000140ul, /*flags=*/0ul, /*opts=*/0x200000000540ul);
  //  ioctl$FUSE_DEV_IOC_CLONE arguments: [
  //    fd: fd_fuse (resource)
  //    cmd: const = 0x8004e500 (4 bytes)
  //    arg: ptr[in, fd_fuse] {
  //      fd_fuse (resource)
  //    }
  //  ]
  *(uint32_t*)0x200000000000 = r[0];
  syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x8004e500,
          /*arg=*/0x200000000000ul);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*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=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  use_temporary_dir();
  loop();
  return 0;
}