// https://syzkaller.appspot.com/bug?id=45630fc10234b4bfcfcf4197ece0ac9649a99389
// 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/mount.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

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=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  install_segv_handler();
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  //  mkdirat arguments: [
  //    fd: fd_dir (resource)
  //    path: ptr[in, buffer] {
  //      buffer: {2e 2f 73 79 73 00} (length 0x6)
  //    }
  //    mode: open_mode = 0x1ff (8 bytes)
  //  ]
  NONFAILING(memcpy((void*)0x200000000000, "./sys\000", 6));
  syscall(
      __NR_mkdirat, /*fd=*/0xffffff9c, /*path=*/0x200000000000ul,
      /*mode=S_IXOTH|S_IWOTH|S_IROTH|S_IXGRP|S_IWGRP|S_IRGRP|S_IXUSR|S_IWUSR|0x100*/
      0x1fful);
  //  mount arguments: [
  //    src: nil
  //    dst: ptr[in, buffer] {
  //      buffer: {2e 2f 73 79 73 00} (length 0x6)
  //    }
  //    type: ptr[in, buffer] {
  //      buffer: {73 79 73 66 73 00} (length 0x6)
  //    }
  //    flags: mount_flags = 0x0 (8 bytes)
  //    data: nil
  //  ]
  NONFAILING(memcpy((void*)0x200000000080, "./sys\000", 6));
  NONFAILING(memcpy((void*)0x2000000000c0, "sysfs\000", 6));
  syscall(__NR_mount, /*src=*/0ul, /*dst=*/0x200000000080ul,
          /*type=*/0x2000000000c0ul, /*flags=*/0ul, /*data=*/0ul);
  //  openat arguments: [
  //    fd: fd_dir (resource)
  //    file: ptr[in, buffer] {
  //      buffer: {2e 2f 73 79 73 2f 6d 6f 64 75 6c 65 2f 64 61 6d 6f 6e 5f 72
  //      65 63 6c 61 69 6d 2f 70 61 72 61 6d 65 74 65 72 73 2f 61 67 67 72 5f
  //      69 6e 74 65 72 76 61 6c 00} (length 0x34)
  //    }
  //    flags: open_flags = 0x2 (4 bytes)
  //    mode: open_mode = 0x0 (2 bytes)
  //  ]
  //  returns fd
  NONFAILING(memcpy((void*)0x200000000140,
                    "./sys/module/damon_reclaim/parameters/aggr_interval\000",
                    52));
  res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x200000000140ul,
                /*flags=O_RDWR*/ 2, /*mode=*/0);
  if (res != -1)
    r[0] = res;
  //  write arguments: [
  //    fd: fd (resource)
  //    buf: ptr[in, buffer] {
  //      buffer: {30 00} (length 0x2)
  //    }
  //    count: len = 0x2 (8 bytes)
  //  ]
  NONFAILING(memcpy((void*)0x200000000180, "0\000", 2));
  syscall(__NR_write, /*fd=*/r[0], /*buf=*/0x200000000180ul, /*count=*/2ul);
  //  openat arguments: [
  //    fd: fd_dir (resource)
  //    file: ptr[in, buffer] {
  //      buffer: {2e 2f 73 79 73 2f 6d 6f 64 75 6c 65 2f 64 61 6d 6f 6e 5f 72
  //      65 63 6c 61 69 6d 2f 70 61 72 61 6d 65 74 65 72 73 2f 65 6e 61 62 6c
  //      65 64 00} (length 0x2e)
  //    }
  //    flags: open_flags = 0x2 (4 bytes)
  //    mode: open_mode = 0x0 (2 bytes)
  //  ]
  //  returns fd
  NONFAILING(memcpy((void*)0x200000000200,
                    "./sys/module/damon_reclaim/parameters/enabled\000", 46));
  res = syscall(__NR_openat, /*fd=*/0xffffff9c, /*file=*/0x200000000200ul,
                /*flags=O_RDWR*/ 2, /*mode=*/0);
  if (res != -1)
    r[1] = res;
  //  write arguments: [
  //    fd: fd (resource)
  //    buf: ptr[in, buffer] {
  //      buffer: {59 00} (length 0x2)
  //    }
  //    count: len = 0x2 (8 bytes)
  //  ]
  NONFAILING(memcpy((void*)0x200000000240, "Y\000", 2));
  syscall(__NR_write, /*fd=*/r[1], /*buf=*/0x200000000240ul, /*count=*/2ul);
  return 0;
}