syzkaller-repros/linux/bd9a7955c514fe8d2b5b9f8d714c6760c4223dd3.c

// WARNING: suspicious RCU usage (4)
// https://syzkaller.appspot.com/bug?id=bd9a7955c514fe8d2b5b9f8d714c6760c4223dd3
// status:fixed
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <sched.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/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)

#define BITMASK_LEN_OFF(type, bf_off, bf_len)                                  \
  (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))

#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)                      \
  if ((bf_off) == 0 && (bf_len) == 0) {                                        \
    *(type*)(addr) = (type)(val);                                              \
  } else {                                                                     \
    type new_val = *(type*)(addr);                                             \
    new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));                     \
    new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off);          \
    *(type*)(addr) = new_val;                                                  \
  }

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

static void loop();

static void sandbox_common()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  setsid();
  struct rlimit rlim;
  rlim.rlim_cur = rlim.rlim_max = 160 << 20;
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 8 << 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 = 0;
  setrlimit(RLIMIT_CORE, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 256;
  setrlimit(RLIMIT_NOFILE, &rlim);
  if (unshare(CLONE_NEWNS)) {
  }
  if (unshare(CLONE_NEWIPC)) {
  }
  if (unshare(0x02000000)) {
  }
  if (unshare(CLONE_NEWUTS)) {
  }
  if (unshare(CLONE_SYSVSEM)) {
  }
}

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

static int do_sandbox_none(void)
{
  if (unshare(CLONE_NEWPID)) {
  }
  int pid = fork();
  if (pid != 0)
    return wait_for_loop(pid);
  setup_common();
  sandbox_common();
  if (unshare(CLONE_NEWNET)) {
  }
  loop();
  exit(1);
}

#ifndef __NR_bpf
#define __NR_bpf 321
#endif

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

void loop(void)
{
  long res = 0;
  *(uint32_t*)0x20000040 = 2;
  *(uint32_t*)0x20000044 = 0x70;
  *(uint8_t*)0x20000048 = 0x15;
  *(uint8_t*)0x20000049 = 1;
  *(uint8_t*)0x2000004a = 0;
  *(uint8_t*)0x2000004b = 0;
  *(uint32_t*)0x2000004c = 0;
  *(uint64_t*)0x20000050 = 0;
  *(uint64_t*)0x20000058 = 0x4040;
  *(uint64_t*)0x20000060 = 0;
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 0, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 1, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 2, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 3, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 4, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 5, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 6, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 7, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 8, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 9, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 10, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 11, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 12, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 13, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 14, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 15, 2);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 17, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 18, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0x80, 19, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 20, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 21, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 22, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 23, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 24, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 25, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 26, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 27, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 28, 1);
  STORE_BY_BITMASK(uint64_t, 0x20000068, 0, 29, 35);
  *(uint32_t*)0x20000070 = 0;
  *(uint32_t*)0x20000074 = 0;
  *(uint64_t*)0x20000078 = 0;
  *(uint64_t*)0x20000080 = 0;
  *(uint64_t*)0x20000088 = 0;
  *(uint64_t*)0x20000090 = 0;
  *(uint32_t*)0x20000098 = 0;
  *(uint32_t*)0x2000009c = 0;
  *(uint64_t*)0x200000a0 = 0;
  *(uint32_t*)0x200000a8 = 0;
  *(uint16_t*)0x200000ac = 0;
  *(uint16_t*)0x200000ae = 0;
  res = syscall(__NR_perf_event_open, 0x20000040, 0, 0, -1, 0);
  if (res != -1)
    r[0] = res;
  *(uint32_t*)0x20000000 = 5;
  *(uint32_t*)0x20000004 = 3;
  *(uint64_t*)0x20000008 = 0x20346fc8;
  memcpy((void*)0x20346fc8, "\x18\x00\x00\x00\xff\xea\x00\x00\x00\x00\x00\x00"
                            "\x00\x00\x99\x01\x95\x00\x00\x00\x00\x00\x00\x00",
         24);
  *(uint64_t*)0x20000010 = 0x200001c0;
  memcpy((void*)0x200001c0, "GPL", 4);
  *(uint32_t*)0x20000018 = 0xfefffffc;
  *(uint32_t*)0x2000001c = 0xfb;
  *(uint64_t*)0x20000020 = 0x20000080;
  *(uint32_t*)0x20000028 = 0;
  *(uint32_t*)0x2000002c = 0;
  *(uint8_t*)0x20000030 = 0;
  *(uint8_t*)0x20000031 = 0;
  *(uint8_t*)0x20000032 = 0;
  *(uint8_t*)0x20000033 = 0;
  *(uint8_t*)0x20000034 = 0;
  *(uint8_t*)0x20000035 = 0;
  *(uint8_t*)0x20000036 = 0;
  *(uint8_t*)0x20000037 = 0;
  *(uint8_t*)0x20000038 = 0;
  *(uint8_t*)0x20000039 = 0;
  *(uint8_t*)0x2000003a = 0;
  *(uint8_t*)0x2000003b = 0;
  *(uint8_t*)0x2000003c = 0;
  *(uint8_t*)0x2000003d = 0;
  *(uint8_t*)0x2000003e = 0;
  *(uint8_t*)0x2000003f = 0;
  *(uint32_t*)0x20000040 = 0;
  *(uint32_t*)0x20000044 = 0;
  res = syscall(__NR_bpf, 5, 0x20000000, 0x48);
  if (res != -1)
    r[1] = res;
  syscall(__NR_ioctl, r[0], 0x40042408, r[1]);
  memcpy((void*)0x20000140, "/dev/net/tun", 13);
  syscall(__NR_openat, 0xffffffffffffff9c, 0x20000140, 0, 0);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  do_sandbox_none();
  return 0;
}