// https://syzkaller.appspot.com/bug?id=4c49b35ab388f250b41a29c25a71c8c229869bf2
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#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/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

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 int inject_fault(int nth)
{
  int fd;
  fd = open("/proc/thread-self/fail-nth", O_RDWR);
  if (fd == -1)
    exit(1);
  char buf[16];
  sprintf(buf, "%d", nth);
  if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf))
    exit(1);
  return fd;
}

static const char* setup_fault()
{
  int fd = open("/proc/self/make-it-fail", O_WRONLY);
  if (fd == -1)
    return "CONFIG_FAULT_INJECTION is not enabled";
  close(fd);
  fd = open("/proc/thread-self/fail-nth", O_WRONLY);
  if (fd == -1)
    return "kernel does not have systematic fault injection support";
  close(fd);
  static struct {
    const char* file;
    const char* val;
    bool fatal;
  } files[] = {
      {"/sys/kernel/debug/failslab/ignore-gfp-wait", "N", true},
      {"/sys/kernel/debug/fail_futex/ignore-private", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/min-order", "0", false},
  };
  unsigned i;
  for (i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].file, files[i].val)) {
      if (files[i].fatal)
        return "failed to write fault injection file";
    }
  }
  return NULL;
}

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)
    ;
}

uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff,
                 0xffffffffffffffff};

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;
  if ((reason = setup_fault()))
    printf("the reproducer may not work as expected: fault injection setup "
           "failed: %s\n",
           reason);
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  memcpy((void*)0x20000040, "./file0\000", 8);
  syscall(__NR_mknodat, /*dirfd=*/0xffffff9c, /*file=*/0x20000040ul,
          /*mode=*/0ul, /*dev=*/0);
  res = syscall(__NR_pipe2, /*pipefd=*/0x200001c0ul, /*flags=*/0ul);
  if (res != -1) {
    r[0] = *(uint32_t*)0x200001c0;
    r[1] = *(uint32_t*)0x200001c4;
  }
  memcpy((void*)0x20000300,
         "\x15\x00\x00\x00\x65\xff\xff\x01\x7f\x00\x0e\x08\x00\x39\x50\x32\x30"
         "\x30\x30",
         19);
  syscall(__NR_write, /*fd=*/r[1], /*data=*/0x20000300ul, /*size=*/0x15ul);
  res = syscall(__NR_dup, /*oldfd=*/r[1]);
  if (res != -1)
    r[2] = res;
  *(uint32_t*)0x20000000 = 0x18;
  *(uint32_t*)0x20000004 = 0;
  *(uint64_t*)0x20000008 = 0;
  *(uint64_t*)0x20000010 = 0;
  syscall(__NR_write, /*fd=*/r[2], /*arg=*/0x20000000ul, /*len=*/0x18ul);
  memset((void*)0x200003c0, 176, 1);
  syscall(__NR_write, /*fd=*/r[2], /*arg=*/0x200003c0ul, /*len=*/0xb0ul);
  *(uint32_t*)0x200000c0 = 0x18;
  *(uint32_t*)0x200000c4 = 0;
  *(uint64_t*)0x200000c8 = 0;
  *(uint32_t*)0x200000d0 = 0;
  *(uint32_t*)0x200000d4 = 0;
  syscall(__NR_write, /*fd=*/r[2], /*arg=*/0x200000c0ul, /*len=*/0x18ul);
  *(uint32_t*)0x20000200 = 0x50;
  *(uint32_t*)0x20000204 = 0;
  *(uint64_t*)0x20000208 = 0;
  *(uint32_t*)0x20000210 = 7;
  *(uint32_t*)0x20000214 = 0x29;
  *(uint32_t*)0x20000218 = 0;
  *(uint32_t*)0x2000021c = 0;
  *(uint16_t*)0x20000220 = 0;
  *(uint16_t*)0x20000222 = 0;
  *(uint32_t*)0x20000224 = 0;
  *(uint32_t*)0x20000228 = 0;
  *(uint16_t*)0x2000022c = 0;
  *(uint16_t*)0x2000022e = 0;
  memset((void*)0x20000230, 0, 32);
  syscall(__NR_write, /*fd=*/r[2], /*arg=*/0x20000200ul, /*len=*/0x50ul);
  memcpy((void*)0x200002c0, "./file0\000", 8);
  memcpy((void*)0x20000080, "9p\000", 3);
  memcpy((void*)0x20000400, "trans=fd,", 9);
  memcpy((void*)0x20000409, "rfdno", 5);
  *(uint8_t*)0x2000040e = 0x3d;
  sprintf((char*)0x2000040f, "0x%016llx", (long long)r[0]);
  *(uint8_t*)0x20000421 = 0x2c;
  memcpy((void*)0x20000422, "wfdno", 5);
  *(uint8_t*)0x20000427 = 0x3d;
  sprintf((char*)0x20000428, "0x%016llx", (long long)r[2]);
  *(uint8_t*)0x2000043a = 0x2c;
  memcpy((void*)0x2000043b, "cache=fscache", 13);
  *(uint8_t*)0x20000448 = 0x2c;
  *(uint8_t*)0x20000449 = 0;
  syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x200002c0ul, /*type=*/0x20000080ul,
          /*flags=*/0ul, /*opts=*/0x20000400ul);
  memcpy((void*)0x2000c380, "./file0\000", 8);
  res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x2000c380ul,
                /*flags=O_NONBLOCK|O_NOFOLLOW|O_CREAT|O_RDWR*/ 0x20842,
                /*mode=*/0);
  if (res != -1)
    r[3] = res;
  *(uint64_t*)0x20000000 = 0x200000c0;
  memset((void*)0x200000c0, 20, 1);
  *(uint64_t*)0x20000008 = 0x1f68;
  syscall(__NR_writev, /*fd=*/r[3], /*vec=*/0x20000000ul, /*vlen=*/2ul);
  inject_fault(39);
  syscall(__NR_readahead, /*fd=*/r[3], /*off=*/5ul,
          /*count=*/0x800000000000dul);
  return 0;
}