syzkaller-repros/linux/4e54cf433396516abecacdaca1ee2e98dc109c8f.c

// general protection fault in rdma_notify
// https://syzkaller.appspot.com/bug?id=4e54cf433396516abecacdaca1ee2e98dc109c8f
// status:fixed
// autogenerated by syzkaller (http://github.com/google/syzkaller)

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

static void test();

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

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[2] = {0xffffffffffffffff, 0xffffffff};
void execute_call(int call)
{
  long res;
  switch (call) {
  case 0:
    memcpy((void*)0x20000140, "/dev/infiniband/rdma_cm", 24);
    res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000140, 2, 0);
    if (res != -1)
      r[0] = res;
    break;
  case 1:
    *(uint32_t*)0x20001c00 = 0;
    *(uint16_t*)0x20001c04 = 0x18;
    *(uint16_t*)0x20001c06 = 0xfa00;
    *(uint64_t*)0x20001c08 = 4;
    *(uint64_t*)0x20001c10 = 0x20001bc0;
    *(uint16_t*)0x20001c18 = 0x117;
    *(uint8_t*)0x20001c1a = 0;
    *(uint8_t*)0x20001c1b = 0;
    *(uint8_t*)0x20001c1c = 0;
    *(uint8_t*)0x20001c1d = 0;
    *(uint8_t*)0x20001c1e = 0;
    *(uint8_t*)0x20001c1f = 0;
    syscall(__NR_write, r[0], 0x20001c00, 0x20);
    break;
  case 2:
    *(uint32_t*)0x20008600 = 0;
    *(uint16_t*)0x20008604 = 0x18;
    *(uint16_t*)0x20008606 = 0xfa00;
    *(uint64_t*)0x20008608 = 0;
    *(uint64_t*)0x20008610 = 0x200085c0;
    *(uint16_t*)0x20008618 = 0;
    *(uint8_t*)0x2000861a = 4;
    *(uint8_t*)0x2000861b = 0;
    *(uint8_t*)0x2000861c = 0;
    *(uint8_t*)0x2000861d = 0;
    *(uint8_t*)0x2000861e = 0;
    *(uint8_t*)0x2000861f = 0;
    syscall(__NR_write, r[0], 0x20008600, 0x20);
    break;
  case 3:
    *(uint32_t*)0x200087c0 = 0;
    *(uint16_t*)0x200087c4 = 0x18;
    *(uint16_t*)0x200087c6 = 0xfa00;
    *(uint64_t*)0x200087c8 = 2;
    *(uint64_t*)0x200087d0 = 0x20008780;
    *(uint16_t*)0x200087d8 = 0x13f;
    *(uint8_t*)0x200087da = 0;
    *(uint8_t*)0x200087db = 0;
    *(uint8_t*)0x200087dc = 0;
    *(uint8_t*)0x200087dd = 0;
    *(uint8_t*)0x200087de = 0;
    *(uint8_t*)0x200087df = 0;
    res = syscall(__NR_write, r[0], 0x200087c0, 0x20);
    if (res != -1)
      r[1] = *(uint32_t*)0x20008780;
    break;
  case 4:
    *(uint32_t*)0x20008640 = 0xf;
    *(uint16_t*)0x20008644 = 8;
    *(uint16_t*)0x20008646 = 0xfa00;
    *(uint32_t*)0x20008648 = r[1];
    *(uint32_t*)0x2000864c = 0;
    syscall(__NR_write, r[0], 0x20008640, 0x10);
    break;
  case 5:
    syscall(__NR_close, r[0]);
    break;
  }
}

void test()
{
  execute(6);
  collide = 1;
  execute(6);
}

int main()
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (;;) {
    loop();
  }
}