// https://syzkaller.appspot.com/bug?id=2291abe7b808272cc87dbe92910139597af23eaa
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <setjmp.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

#ifndef __NR_userfaultfd
#define __NR_userfaultfd 323
#endif

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;                                                                        \
  })

uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff};

int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul,
          /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
  install_segv_handler();
  intptr_t res = 0;
  NONFAILING(memcpy((void*)0x20000180,
                    "gre0\000\000\000\000\000\000\000\000\000\000\000\000",
                    16));
  NONFAILING(*(uint64_t*)0x20000190 = 0x20000100);
  NONFAILING(memcpy(
      (void*)0x20000100,
      "s\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000", 16));
  NONFAILING(*(uint32_t*)0x20000110 = 0);
  NONFAILING(
      memcpy((void*)0x20000114,
             "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x4d\x00\x00\x34"
             "\x00\x00\x00\x00\x00\x00\x90\x78\xac\x1e\x00\x01\xac\x1e\x00\x01"
             "\x44\x20\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
             "\x00\x20\x00\x00\xff\xff\xff\xff\xff\xff\xff\xff\x00\x00\x00\x06",
             64));
  syscall(__NR_ioctl, /*fd=*/-1, /*cmd=*/0x89f3, /*arg=*/0x20000180ul);
  res = syscall(__NR_userfaultfd, /*flags=*/0x801ul);
  if (res != -1)
    r[0] = res;
  NONFAILING(*(uint64_t*)0x20000000 = 0xaa);
  NONFAILING(*(uint64_t*)0x20000008 = 0);
  NONFAILING(*(uint64_t*)0x20000010 = 0);
  syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc018aa3f, /*arg=*/0x20000000ul);
  NONFAILING(memcpy((void*)0x20000080, "memory.events\000", 14));
  res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x20000080ul,
                /*flags=*/0x275aul, /*mode=*/0ul);
  if (res != -1)
    r[1] = res;
  syscall(__NR_write, /*fd=*/r[1], /*data=*/0x20000100ul, /*len=*/0xfeccul);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x3000ul, /*prot=*/1ul,
          /*flags=*/0x12ul, /*fd=*/r[1], /*offset=*/0ul);
  NONFAILING(*(uint64_t*)0x20000040 = 0x20ffb000);
  NONFAILING(*(uint64_t*)0x20000048 = 0x20ffd000);
  NONFAILING(*(uint64_t*)0x20000050 = 0x4000);
  NONFAILING(*(uint64_t*)0x20000058 = 0);
  NONFAILING(*(uint64_t*)0x20000060 = 0);
  syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc028aa03, /*arg=*/0x20000040ul);
  return 0;
}