// https://syzkaller.appspot.com/bug?id=12ffde0f016e7572c26e71bda369ec9f5b857e63
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <pthread.h>
#include <setjmp.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>

#include <linux/futex.h>

#ifndef __NR_io_uring_setup
#define __NR_io_uring_setup 425
#endif
#ifndef __NR_mmap
#define __NR_mmap 192
#endif
#ifndef __NR_mremap
#define __NR_mremap 163
#endif
#undef __NR_mmap
#define __NR_mmap __NR_mmap2

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 thread_start(void* (*fn)(void*), void* arg)
{
  pthread_t th;
  pthread_attr_t attr;
  pthread_attr_init(&attr);
  pthread_attr_setstacksize(&attr, 128 << 10);
  int i = 0;
  for (; i < 100; i++) {
    if (pthread_create(&th, &attr, fn, arg) == 0) {
      pthread_attr_destroy(&attr);
      return;
    }
    if (errno == EAGAIN) {
      usleep(50);
      continue;
    }
    break;
  }
  exit(1);
}

typedef struct {
  int state;
} event_t;

static void event_init(event_t* ev)
{
  ev->state = 0;
}

static void event_reset(event_t* ev)
{
  ev->state = 0;
}

static void event_set(event_t* ev)
{
  if (ev->state)
    exit(1);
  __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE);
  syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000);
}

static void event_wait(event_t* ev)
{
  while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
    syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0);
}

static int event_isset(event_t* ev)
{
  return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE);
}

static int event_timedwait(event_t* ev, uint64_t timeout)
{
  uint64_t start = current_time_ms();
  uint64_t now = start;
  for (;;) {
    uint64_t remain = timeout - (now - start);
    struct timespec ts;
    ts.tv_sec = remain / 1000;
    ts.tv_nsec = (remain % 1000) * 1000 * 1000;
    syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts);
    if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
      return 1;
    now = current_time_ms();
    if (now - start > timeout)
      return 0;
  }
}

#define SIZEOF_IO_URING_SQE 64
#define SIZEOF_IO_URING_CQE 16

#define IORING_SETUP_SQE128 (1U << 10)
#define IORING_SETUP_CQE32 (1U << 11)

struct io_sqring_offsets {
  uint32_t head;
  uint32_t tail;
  uint32_t ring_mask;
  uint32_t ring_entries;
  uint32_t flags;
  uint32_t dropped;
  uint32_t array;
  uint32_t resv1;
  uint64_t user_addr;
};

struct io_cqring_offsets {
  uint32_t head;
  uint32_t tail;
  uint32_t ring_mask;
  uint32_t ring_entries;
  uint32_t overflow;
  uint32_t cqes;
  uint32_t flags;
  uint32_t resv1;
  uint64_t user_addr;
};

struct io_uring_params {
  uint32_t sq_entries;
  uint32_t cq_entries;
  uint32_t flags;
  uint32_t sq_thread_cpu;
  uint32_t sq_thread_idle;
  uint32_t features;
  uint32_t resv[4];
  struct io_sqring_offsets sq_off;
  struct io_cqring_offsets cq_off;
};

static long io_uring_sqe_size(struct io_uring_params* params)
{
  return SIZEOF_IO_URING_SQE << !!(params->flags & IORING_SETUP_SQE128);
}

static long io_uring_cqe_size(struct io_uring_params* params)
{
  return SIZEOF_IO_URING_CQE << !!(params->flags & IORING_SETUP_CQE32);
}

#define IORING_OFF_SQ_RING 0ULL
#define IORING_OFF_SQES 0x10000000ULL
static long syz_io_uring_setup(volatile long a0, volatile long a1,
                               volatile long a2, volatile long a3,
                               volatile long a4)
{
  uint32_t entries = (uint32_t)a0;
  struct io_uring_params* setup_params = (struct io_uring_params*)a1;
  void** ring_params_ptr_out = (void**)a2;
  void** ring_ptr_out = (void**)a3;
  void** sqes_ptr_out = (void**)a4;
  uint32_t fd_io_uring = syscall(__NR_io_uring_setup, entries, setup_params);
  *ring_params_ptr_out = (void*)setup_params;
  uint32_t sq_ring_sz =
      setup_params->sq_off.array + setup_params->sq_entries * sizeof(uint32_t);
  uint32_t cq_ring_sz =
      setup_params->cq_off.cqes +
      setup_params->cq_entries * io_uring_cqe_size(setup_params);
  uint32_t ring_sz = sq_ring_sz > cq_ring_sz ? sq_ring_sz : cq_ring_sz;
  *ring_ptr_out =
      mmap(0, ring_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
           fd_io_uring, IORING_OFF_SQ_RING);
  uint32_t sqes_sz = setup_params->sq_entries * io_uring_sqe_size(setup_params);
  *sqes_ptr_out = mmap(0, sqes_sz, PROT_READ | PROT_WRITE,
                       MAP_SHARED | MAP_POPULATE, fd_io_uring, IORING_OFF_SQES);
  uint32_t* array =
      (uint32_t*)((uintptr_t)*ring_ptr_out + setup_params->sq_off.array);
  for (uint32_t index = 0; index < setup_params->sq_entries; index++)
    array[index] = index;
  return fd_io_uring;
}

struct thread_t {
  int created, call;
  event_t ready, done;
};

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

static void* thr(void* arg)
{
  struct thread_t* th = (struct thread_t*)arg;
  for (;;) {
    event_wait(&th->ready);
    event_reset(&th->ready);
    execute_call(th->call);
    __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
    event_set(&th->done);
  }
  return 0;
}

static void loop(void)
{
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  int i, call, thread;
  for (call = 0; call < 4; call++) {
    for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0]));
         thread++) {
      struct thread_t* th = &threads[thread];
      if (!th->created) {
        th->created = 1;
        event_init(&th->ready);
        event_init(&th->done);
        event_set(&th->done);
        thread_start(thr, th);
      }
      if (!event_isset(&th->done))
        continue;
      event_reset(&th->done);
      th->call = call;
      __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
      event_set(&th->ready);
      event_timedwait(&th->done, 50);
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
}

void execute_call(int call)
{
  switch (call) {
  case 0:
    //  syz_io_uring_setup arguments: [
    //    entries: int32 = 0x186 (4 bytes)
    //    params: ptr[inout, io_uring_params] {
    //      io_uring_params {
    //        sq_entries: int32 = 0x0 (4 bytes)
    //        cq_entries: int32 = 0x0 (4 bytes)
    //        flags: io_uring_setup_flags = 0x13100 (4 bytes)
    //        sq_thread_cpu: int32 = 0x0 (4 bytes)
    //        sq_thread_idle: int32 = 0x0 (4 bytes)
    //        features: int32 = 0x0 (4 bytes)
    //        wq_fd: fd_io_uring (resource)
    //        resv: buffer: {00 00 00 00 00 00 00 00 00 00 00 00} (length 0xc)
    //        sq_off: io_sqring_offsets {
    //          head: int32 = 0x0 (4 bytes)
    //          tail: int32 = 0x0 (4 bytes)
    //          ring_mask: int32 = 0x0 (4 bytes)
    //          ring_entries: int32 = 0x0 (4 bytes)
    //          flags: int32 = 0x0 (4 bytes)
    //          dropped: int32 = 0x0 (4 bytes)
    //          array: int32 = 0x0 (4 bytes)
    //          resv1: int32 = 0x0 (4 bytes)
    //          user_addr: int64 = 0x0 (8 bytes)
    //        }
    //        cq_off: io_cqring_offsets {
    //          head: int32 = 0x0 (4 bytes)
    //          tail: int32 = 0x0 (4 bytes)
    //          ring_mask: int32 = 0x0 (4 bytes)
    //          ring_entries: int32 = 0x0 (4 bytes)
    //          overflow: int32 = 0x0 (4 bytes)
    //          cqes: int32 = 0x0 (4 bytes)
    //          flags: int32 = 0x0 (4 bytes)
    //          resv1: int32 = 0x0 (4 bytes)
    //          user_addr: int64 = 0x0 (8 bytes)
    //        }
    //      }
    //    }
    //    ring_params_ptr: nil
    //    ring_ptr: nil
    //    sqes_ptr: nil
    //  ]
    //  returns fd_io_uring
    NONFAILING(*(uint32_t*)0x80000084 = 0);
    NONFAILING(*(uint32_t*)0x80000088 = 0x13100);
    NONFAILING(*(uint32_t*)0x8000008c = 0);
    NONFAILING(*(uint32_t*)0x80000090 = 0);
    NONFAILING(*(uint32_t*)0x80000098 = -1);
    NONFAILING(memset((void*)0x8000009c, 0, 12));
    NONFAILING(syz_io_uring_setup(/*entries=*/0x186, /*params=*/0x80000080,
                                  /*ring_params_ptr=*/0, /*ring_ptr=*/0,
                                  /*sqes_ptr=*/0));
    break;
  case 1:
    //  mremap arguments: [
    //    addr: VMA[0x4000]
    //    len: len = 0x200000 (4 bytes)
    //    newlen: len = 0x4000 (4 bytes)
    //    flags: mremap_flags = 0x3 (4 bytes)
    //    newaddr: VMA[0x4000]
    //  ]
    syscall(__NR_mremap, /*addr=*/0x80002000, /*len=*/0x200000,
            /*newlen=*/0x4000, /*flags=MREMAP_FIXED|MREMAP_MAYMOVE*/ 3,
            /*newaddr=*/0x80ffc000);
    break;
  case 2:
    //  mremap arguments: [
    //    addr: VMA[0x4000]
    //    len: len = 0x4000 (4 bytes)
    //    newlen: len = 0x4000 (4 bytes)
    //    flags: mremap_flags = 0x7 (4 bytes)
    //    newaddr: VMA[0x4000]
    //  ]
    syscall(__NR_mremap, /*addr=*/0x80ffc000, /*len=*/0x4000, /*newlen=*/0x4000,
            /*flags=MREMAP_DONTUNMAP|MREMAP_FIXED|MREMAP_MAYMOVE*/ 7,
            /*newaddr=*/0x80002000);
    break;
  case 3:
    //  mremap arguments: [
    //    addr: VMA[0x2000]
    //    len: len = 0x2000 (4 bytes)
    //    newlen: len = 0x1000 (4 bytes)
    //    flags: mremap_flags = 0x0 (4 bytes)
    //    newaddr: VMA[0x1000]
    //  ]
    syscall(__NR_mremap, /*addr=*/0x80ffd000, /*len=*/0x2000, /*newlen=*/0x1000,
            /*flags=*/0, /*newaddr=*/0x80ffe000);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x7ffff000, /*len=*/0x1000, /*prot=*/0,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32,
          /*fd=*/(intptr_t)-1, /*offset=*/0);
  syscall(__NR_mmap, /*addr=*/0x80000000, /*len=*/0x1000000,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32,
          /*fd=*/(intptr_t)-1, /*offset=*/0);
  syscall(__NR_mmap, /*addr=*/0x81000000, /*len=*/0x1000, /*prot=*/0,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32,
          /*fd=*/(intptr_t)-1, /*offset=*/0);
  const char* reason;
  (void)reason;
  install_segv_handler();
  loop();
  return 0;
}