// https://syzkaller.appspot.com/bug?id=44f63704b28fe02f0ea1185bce77908b623b8f20
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <sched.h>
#include <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#include <linux/capability.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;                                                                        \
  })

static bool write_file(const char* file, const char* what, ...)
{
  char buf[1024];
  va_list args;
  va_start(args, what);
  vsnprintf(buf, sizeof(buf), what, args);
  va_end(args);
  buf[sizeof(buf) - 1] = 0;
  int len = strlen(buf);
  int fd = open(file, O_WRONLY | O_CLOEXEC);
  if (fd == -1)
    return false;
  if (write(fd, buf, len) != len) {
    int err = errno;
    close(fd);
    errno = err;
    return false;
  }
  close(fd);
  return true;
}

static void setup_gadgetfs();
static void setup_binderfs();
static void setup_fusectl();
static void sandbox_common_mount_tmpfs(void)
{
  write_file("/proc/sys/fs/mount-max", "100000");
  if (mkdir("./syz-tmp", 0777))
    exit(1);
  if (mount("", "./syz-tmp", "tmpfs", 0, NULL))
    exit(1);
  if (mkdir("./syz-tmp/newroot", 0777))
    exit(1);
  if (mkdir("./syz-tmp/newroot/dev", 0700))
    exit(1);
  unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE;
  if (mount("/dev", "./syz-tmp/newroot/dev", NULL, bind_mount_flags, NULL))
    exit(1);
  if (mkdir("./syz-tmp/newroot/proc", 0700))
    exit(1);
  if (mount("syz-proc", "./syz-tmp/newroot/proc", "proc", 0, NULL))
    exit(1);
  if (mkdir("./syz-tmp/newroot/selinux", 0700))
    exit(1);
  const char* selinux_path = "./syz-tmp/newroot/selinux";
  if (mount("/selinux", selinux_path, NULL, bind_mount_flags, NULL)) {
    if (errno != ENOENT)
      exit(1);
    if (mount("/sys/fs/selinux", selinux_path, NULL, bind_mount_flags, NULL) &&
        errno != ENOENT)
      exit(1);
  }
  if (mkdir("./syz-tmp/newroot/sys", 0700))
    exit(1);
  if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL))
    exit(1);
  if (mount("/sys/kernel/debug", "./syz-tmp/newroot/sys/kernel/debug", NULL,
            bind_mount_flags, NULL) &&
      errno != ENOENT)
    exit(1);
  if (mount("/sys/fs/smackfs", "./syz-tmp/newroot/sys/fs/smackfs", NULL,
            bind_mount_flags, NULL) &&
      errno != ENOENT)
    exit(1);
  if (mount("/proc/sys/fs/binfmt_misc",
            "./syz-tmp/newroot/proc/sys/fs/binfmt_misc", NULL, bind_mount_flags,
            NULL) &&
      errno != ENOENT)
    exit(1);
  if (mkdir("./syz-tmp/newroot/syz-inputs", 0700))
    exit(1);
  if (mount("/syz-inputs", "./syz-tmp/newroot/syz-inputs", NULL,
            bind_mount_flags | MS_RDONLY, NULL) &&
      errno != ENOENT)
    exit(1);
  if (mkdir("./syz-tmp/pivot", 0777))
    exit(1);
  if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) {
    if (chdir("./syz-tmp"))
      exit(1);
  } else {
    if (chdir("/"))
      exit(1);
    if (umount2("./pivot", MNT_DETACH))
      exit(1);
  }
  if (chroot("./newroot"))
    exit(1);
  if (chdir("/"))
    exit(1);
  setup_gadgetfs();
  setup_binderfs();
  setup_fusectl();
}

static void setup_gadgetfs()
{
  if (mkdir("/dev/gadgetfs", 0777)) {
  }
  if (mount("gadgetfs", "/dev/gadgetfs", "gadgetfs", 0, NULL)) {
  }
}

static void setup_fusectl()
{
  if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
  }
}

static void setup_binderfs()
{
  if (mkdir("/dev/binderfs", 0777)) {
  }
  if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) {
  }
  if (symlink("/dev/binderfs", "./binderfs")) {
  }
}

static void loop();

static void sandbox_common()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  if (getppid() == 1)
    exit(1);
  struct rlimit rlim;
  rlim.rlim_cur = rlim.rlim_max = (200 << 20);
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 32 << 20;
  setrlimit(RLIMIT_MEMLOCK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 136 << 20;
  setrlimit(RLIMIT_FSIZE, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 1 << 20;
  setrlimit(RLIMIT_STACK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 128 << 20;
  setrlimit(RLIMIT_CORE, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 256;
  setrlimit(RLIMIT_NOFILE, &rlim);
  if (unshare(CLONE_NEWNS)) {
  }
  if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
  }
  if (unshare(CLONE_NEWIPC)) {
  }
  if (unshare(0x02000000)) {
  }
  if (unshare(CLONE_NEWUTS)) {
  }
  if (unshare(CLONE_SYSVSEM)) {
  }
  typedef struct {
    const char* name;
    const char* value;
  } sysctl_t;
  static const sysctl_t sysctls[] = {
      {"/proc/sys/kernel/shmmax", "16777216"},
      {"/proc/sys/kernel/shmall", "536870912"},
      {"/proc/sys/kernel/shmmni", "1024"},
      {"/proc/sys/kernel/msgmax", "8192"},
      {"/proc/sys/kernel/msgmni", "1024"},
      {"/proc/sys/kernel/msgmnb", "1024"},
      {"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
  };
  unsigned i;
  for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
    write_file(sysctls[i].name, sysctls[i].value);
}

static int wait_for_loop(int pid)
{
  if (pid < 0)
    exit(1);
  int status = 0;
  while (waitpid(-1, &status, __WALL) != pid) {
  }
  return WEXITSTATUS(status);
}

static void drop_caps(void)
{
  struct __user_cap_header_struct cap_hdr = {};
  struct __user_cap_data_struct cap_data[2] = {};
  cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
  cap_hdr.pid = getpid();
  if (syscall(SYS_capget, &cap_hdr, &cap_data))
    exit(1);
  const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
  cap_data[0].effective &= ~drop;
  cap_data[0].permitted &= ~drop;
  cap_data[0].inheritable &= ~drop;
  if (syscall(SYS_capset, &cap_hdr, &cap_data))
    exit(1);
}

static int do_sandbox_none(void)
{
  if (unshare(CLONE_NEWPID)) {
  }
  int pid = fork();
  if (pid != 0)
    return wait_for_loop(pid);
  sandbox_common();
  drop_caps();
  if (unshare(CLONE_NEWNET)) {
  }
  write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535");
  sandbox_common_mount_tmpfs();
  loop();
  exit(1);
}

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

void loop(void)
{
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  NONFAILING(memcpy((void*)0x200000000500, "/dev/ashmem\000", 12));
  res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul,
                /*file=*/0x200000000500ul, /*flags=*/0, /*mode=*/0);
  if (res != -1)
    r[0] = res;
  syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x40087703, /*arg=*/8ul);
  syscall(__NR_mmap, /*addr=*/0x200000701000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_PRIVATE*/ 0x12ul, /*fd=*/r[0], /*offset=*/0ul);
  NONFAILING(memcpy((void*)0x2000000002c0, "/selinux/policy\000", 16));
  res = syscall(__NR_openat, /*fd=*/0xffffff9cul, /*file=*/0x2000000002c0ul,
                /*flags=*/0, /*mode=*/0);
  if (res != -1)
    r[1] = res;
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0xb36000ul,
          /*prot=PROT_GROWSDOWN|PROT_SEM|PROT_WRITE*/ 0x100000aul,
          /*flags=MAP_FIXED|MAP_PRIVATE*/ 0x12ul, /*fd=*/r[1], /*offset=*/0ul);
  NONFAILING(memcpy(
      (void*)0x200000002600,
      "\000\000\003\006\000\000\000\005\000x\222\022\254\006^"
      "\276wV\363\"\304\004\273\00642\234\032\321\313{"
      "\260\326\036\000gQ\312\016U\367\'\214\301\306\273\305\034\367\257\225"
      "\203="
      "\t7\226\032\255\320\320\356\234\2262\bu\272\374\256\302\031\353\221\311"
      "\t\274\301\313\272\343\216\366\211\302\'\337n(Q=v-<\r\321?$"
      "\213\027Bn\027h\033\254\374\202\034\364\320\365\325\200`4/"
      "\351\025\232\237\360:\375$\255\273\232|"
      "c\374\"\356\304\223Q\202\026\277\343c\215 \017\261\351\362o "
      "\000\000\000\000\000\000\000H\257\t\030\310\033\036\276\330>\354\237~"
      "\247\367\257dd\361\333jE\001\321sD\211\224&\\U\f\030\231]"
      "\253a\3513\001\2423\311hP1\334-\'\320\236}\211\377\214\354^\204\031\237_"
      "D\275t/"
      "\'\366\303\214\270\vS\200\255\370\277\242\240\231\302\026="
      "\314\260\0337\343-"
      "\'\002\026\365\346\223\002E\n\350\000\000\214\355\021\367\362J\366\220A@"
      "\001\023\307`g\313\327\333\036\262\311\375\367\251\226\370/"
      "0Xd\317\271\242\035\023\217C\322&"
      "\330\235\213\340E\322\306\032\363\250\016\272\354Ov$"
      "\310\"\a\327T\373\374\372uT\370\236\206\357.\366<\277B\347\200\032\a\t+"
      "x_B=\347\245\211\373\242\306\227\353\336cY{"
      "\016\302\000\000\000\000\000\000\000\a\364\210\006\343\313\310\340\314\v"
      "E\030\"\207\240\251:\316Y\360\242\340\235\214\216\021\267\230\245\332$"
      "\224D\264\362>\001\000+\372\251 "
      "\341\023Y\206\330\277H\306\234\214s4\r\315\321\203JT\371\242\203?"
      "\263\017\306&\035\243\304\303\322\375\255\2435o\350\315^/"
      "\330\026\\n\237J\364\n\222c\252\335T&L<+\031R\a\374\362\027\270$\251]"
      "\302\\\332<\310d.w\234\2574\273\350Co\263\330\202\222\272+"
      "\231PXB\334\272y\240s<\222k\vJTRW\3026\006\020\222\307\2455\237Z\377*"
      "ir\036\350\a\000\000\000\000\000\000\000\210\031\367\335\250\357\240\230"
      "\315\201\020>\307{\204\271\300B\341\t\000\272Qj\201\310\370\0246%"
      "Z\203H\253F\030<\206h\001=\003i\304\t\216/"
      "\022\a\337\347zU\035\025\016\301?\352u\264\204\004;\305[\nja\271\'\311#"
      "\374x\000\000X\364\351\037\315\005\017z_\215,^"
      "\336\375\321\276d\355\241\365\306(p\264;\016\030\367/"
      "A\375\222\320}ur\252g\333&e$\f\rrT\330\210~"
      "\023\3022t\366\364Fs\301\005\372\231\025\207\024\023$\t\250?"
      "\356\224W\216\341\314\303U\204\306]:\232|"
      "W\354\204\030\bb\202\217\300\253\343a\231\027\205\232\005\261\022K\\\362"
      "\325\b^[D~~\204\\\344\000B\005\324\352\352\177=\306:"
      "\\N\303\267Vw\306\234\226s\252HL\226\3072\n\030Ynj\316TS\373l\017\2378M"
      "\f\211\241\322Hs`\213p\212\304%\370\0353\nV\232\257\037\3716^"
      "\223\301\257)\rg\206\326\352\251\017\232\361V\033\277\213\'-"
      "\253\216\t7\323\367\251v\373Y\346\233^d\214\261\335",
      822));
  syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x40087708,
          /*arg=*/0x200000002600ul);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul,
          /*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=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  install_segv_handler();
  do_sandbox_none();
  return 0;
}