syzkaller-repros/linux/54315878fa24956437453737e1e90e0a3d8b37f5.c

// KASAN: use-after-free Read in xfrm6_tunnel_destroy
// https://syzkaller.appspot.com/bug?id=54315878fa24956437453737e1e90e0a3d8b37f5
// status:open
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <sched.h>
#include <signal.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 <time.h>
#include <unistd.h>

unsigned long long procid;

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 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);
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  int i;
  for (i = 0; i < 100; i++) {
    if (waitpid(-1, status, WNOHANG | __WALL) == pid)
      return;
    usleep(1000);
  }
  DIR* dir = opendir("/sys/fs/fuse/connections");
  if (dir) {
    for (;;) {
      struct dirent* ent = readdir(dir);
      if (!ent)
        break;
      if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
        continue;
      char abort[300];
      snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
               ent->d_name);
      int fd = open(abort, O_WRONLY);
      if (fd == -1) {
        continue;
      }
      if (write(fd, abort, 1) < 0) {
      }
      close(fd);
    }
    closedir(dir);
  } else {
  }
  while (waitpid(-1, status, __WALL) != pid) {
  }
}

#define SYZ_HAVE_SETUP_TEST 1
static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
}

#define SYZ_HAVE_RESET_TEST 1
static void reset_test()
{
  int fd;
  for (fd = 3; fd < 30; fd++)
    close(fd);
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter;
  for (iter = 0;; iter++) {
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      setup_test();
      execute_one();
      reset_test();
      exit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      sleep_ms(1);
      if (current_time_ms() - start < 5 * 1000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
  }
}

uint64_t r[3] = {0xffffffffffffffff, 0x0, 0xffffffffffffffff};

void execute_one(void)
{
  long res = 0;
  res = syscall(__NR_inotify_init1, 0);
  if (res != -1)
    r[0] = res;
  syscall(__NR_fcntl, r[0], 8, -1);
  res = syscall(__NR_fcntl, r[0], 0x10, 0x20000000);
  if (res != -1)
    r[1] = *(uint32_t*)0x20000004;
  syscall(__NR_ptrace, 0x4206, r[1], 0, 0);
  syscall(__NR_ptrace, 0x4207, r[1]);
  syscall(__NR_ptrace, 0xd, r[1], 0, 0x20000100);
  res = syscall(__NR_socket, 0xf, 3, 2);
  if (res != -1)
    r[2] = res;
  *(uint64_t*)0x20000180 = 0;
  *(uint32_t*)0x20000188 = 0;
  *(uint64_t*)0x20000190 = 0x20000040;
  *(uint64_t*)0x20000040 = 0x20000080;
  *(uint64_t*)0x20000048 = 0;
  *(uint64_t*)0x20000198 = 1;
  *(uint64_t*)0x200001a0 = 0;
  *(uint64_t*)0x200001a8 = 0;
  *(uint32_t*)0x200001b0 = 0;
  syscall(__NR_sendmsg, -1, 0x20000180, 0);
  *(uint64_t*)0x20000000 = 0x40000000;
  *(uint32_t*)0x20000008 = 0;
  *(uint64_t*)0x20000010 = 0x20000040;
  *(uint64_t*)0x20000040 = 0x200001c0;
  memcpy((void*)0x200001c0,
         "\x02\x03\x00\x09\x10\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02"
         "\x00\x13\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x05\x00"
         "\x06\x00\x00\x00\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x00\x00\x00\x00\x02\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00"
         "\x00\x00\x00\x05\x00\x05\x00\x00\x00\x00\x00\x0a\x00\x00\x00\x00\x00"
         "\x00\x00\xff\x17\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x17\x04\x00\x00\x00\x00\x00\x00\x00",
         128);
  *(uint64_t*)0x20000048 = 0x80;
  *(uint64_t*)0x20000018 = 1;
  *(uint64_t*)0x20000020 = 0;
  *(uint64_t*)0x20000028 = 0;
  *(uint32_t*)0x20000030 = 0;
  syscall(__NR_sendmsg, -1, 0x20000000, 0);
  syscall(__NR_sendmmsg, r[2], 0x20000180, 0x400000000000117, 0);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 8; procid++) {
    if (fork() == 0) {
      do_sandbox_none();
    }
  }
  sleep(1000000);
  return 0;
}