syzkaller-repros/linux/ae0125a57674f57b675fad8f1440eb2be4790fba.c

// WARNING in ext4_set_page_dirty
// https://syzkaller.appspot.com/bug?id=ae0125a57674f57b675fad8f1440eb2be4790fba
// status:open
// autogenerated by syzkaller (http://github.com/google/syzkaller)

#define _GNU_SOURCE
#include <endian.h>
#include <fcntl.h>
#include <linux/futex.h>
#include <pthread.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <unistd.h>

static uintptr_t syz_open_procfs(uintptr_t a0, uintptr_t a1)
{

  char buf[128];
  memset(buf, 0, sizeof(buf));
  if (a0 == 0) {
    snprintf(buf, sizeof(buf), "/proc/self/%s", (char*)a1);
  } else if (a0 == (uintptr_t)-1) {
    snprintf(buf, sizeof(buf), "/proc/thread-self/%s", (char*)a1);
  } else {
    snprintf(buf, sizeof(buf), "/proc/self/task/%d/%s", (int)a0, (char*)a1);
  }
  int fd = open(buf, O_RDWR);
  if (fd == -1)
    fd = open(buf, O_RDONLY);
  return fd;
}

static void execute_one();
extern unsigned long long procid;

void loop()
{
  while (1) {
    execute_one();
  }
}

struct thread_t {
  int created, running, call;
  pthread_t th;
};

static struct thread_t threads[16];
static void execute_call(int call);
static int running;
static int collide;

static void* thr(void* arg)
{
  struct thread_t* th = (struct thread_t*)arg;
  for (;;) {
    while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE))
      syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0);
    execute_call(th->call);
    __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
    __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE);
    syscall(SYS_futex, &th->running, FUTEX_WAKE);
  }
  return 0;
}

static void execute(int num_calls)
{
  int call, thread;
  running = 0;
  for (call = 0; call < num_calls; call++) {
    for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) {
      struct thread_t* th = &threads[thread];
      if (!th->created) {
        th->created = 1;
        pthread_attr_t attr;
        pthread_attr_init(&attr);
        pthread_attr_setstacksize(&attr, 128 << 10);
        pthread_create(&th->th, &attr, thr, th);
      }
      if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) {
        th->call = call;
        __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
        __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE);
        syscall(SYS_futex, &th->running, FUTEX_WAKE);
        if (collide && call % 2)
          break;
        struct timespec ts;
        ts.tv_sec = 0;
        ts.tv_nsec = 20 * 1000 * 1000;
        syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts);
        if (running)
          usleep((call == num_calls - 1) ? 10000 : 1000);
        break;
      }
    }
  }
}

uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff};
unsigned long long procid;
void execute_call(int call)
{
  long res;
  switch (call) {
  case 0:
    memcpy((void*)0x20000100,
           "\x2f\x65\x78\x65\x00\x00\x00\x00\x00\x04\x09\x00\x4b\xdd\xd9\xf1"
           "\x91\xbe\x10\xee\xbf\x00\x0e\xe9\xff\x07\x00\x00\x00\x00\x00\x00"
           "\x54\xfa\x07\x42\x4a\xde\xe9\x16\xd2\xda\x75\xaf\xe7\x0b\x35\xa0"
           "\xfd\x6a\x1f\x02\x00\xf5\xab\x26\xd7\xa0\x71\xfb\x35\x33\x1c\xe3"
           "\x9c\x5a\x65\x68\x64\x10\x72\x1e\xe2\xdb\x6a\x74\xe3\x33\x26\x53",
           80);
    res = syz_open_procfs(0, 0x20000100);
    if (res != -1)
      r[0] = res;
    break;
  case 1:
    syscall(__NR_fcntl, r[0], 4, 0x5ffe);
    break;
  case 2:
    memcpy((void*)0x20000700, "./bus", 6);
    res = syscall(__NR_creat, 0x20000700, 0);
    if (res != -1)
      r[1] = res;
    break;
  case 3:
    syscall(__NR_fcntl, r[1], 4, 0x6100);
    break;
  case 4:
    syscall(__NR_ftruncate, r[1], 0x8200);
    break;
  case 5:
    memcpy((void*)0x200001c0, "./bus", 6);
    res = syscall(__NR_open, 0x200001c0, 0x141042, 0xfffffffffffffffc);
    if (res != -1)
      r[2] = res;
    break;
  case 6:
    syscall(__NR_mmap, 0x20001000, 0xa000, 0x800002, 0x11, r[2], 0);
    break;
  case 7:
    memcpy((void*)0x20000040, "./bus", 6);
    memcpy((void*)0x20000080, "trusted.", 8);
    memcpy((void*)0x20000088, ",", 2);
    syscall(__NR_removexattr, 0x20000040, 0x20000080);
    break;
  case 8:
    memcpy((void*)0x20000000, "./bus", 6);
    syscall(__NR_open, 0x20000000, 0, 0);
    break;
  case 9:
    *(uint64_t*)0x20000340 = 0;
    syscall(__NR_sendfile, r[1], r[2], 0x20000340, 0x8000fffffffe);
    break;
  case 10:
    syscall(__NR_pread64, r[0], 0x20002000, 0xfffffd80, 0);
    break;
  }
}

void execute_one()
{
  execute(11);
  collide = 1;
  execute(11);
}

int main()
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 8; procid++) {
    if (fork() == 0) {
      for (;;) {
        loop();
      }
    }
  }
  sleep(1000000);
  return 0;
}