syzkaller-repros/linux/50676d5a49305fb284f6d45c806efb5b0908071f.c

// panic: hashed child "stat\t\xe9\xdc\xdf\x02\x02\x98\xcc\xf3<\xdf-\xea\xc8\xc1w\xff\x17\x12H\xe9\x11\x93Q\nI\xf81U\ro}\xe
// https://syzkaller.appspot.com/bug?id=50676d5a49305fb284f6d45c806efb5b0908071f
// status:fixed
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/prctl.h>
#include <sys/stat.h>
#include <sys/syscall.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 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 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();
  write_file("/proc/self/oom_score_adj", "1000");
}

#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;
    }
  }
}

void execute_one(void)
{
  memcpy(
      (void*)0x20000440,
      "stat\t\351\334\337\002\002\230\314\363<\337-"
      "\352\310\301w\377\027\022H\351\021\223Q\nI\3701U\ro}"
      "\346l\3667\275\277\023\021\222\f\212&\355\244\334\304x!"
      "\235\265\021k4\323\033\005\022\245`"
      "Pq\032\331\346\246\365\352\255\204sf\222\337\217\342\246\203\3041p\006H"
      "\250T\a\332\202\360\312\301\003\035\315Rc\347\036Q\360\305S\f\275\335"
      "\313\030\305a\217Z\037\227\027\345\243\332\026\221\020\252JA\337B\347"
      "\270\314I(u.\242\245^\232\242gx\271\366[\256q9\305\230S\340k\304p\342]"
      "\n\230#h\003U\270\252\034\227\312.x\223\276\223\255\327]&"
      "\212\241\237\306\237x\365)\f~\2019\001e\236#"
      "\306\034Qp\226k\215C\211\025mK\2620\2221\214\230\201\2519\347\242*"
      "\271\233\252\325\227\272\247M`\001\307\020\225\330\335\312{"
      "\305o\231L\340(P\345Aw\177\343\"\347\375\224 "
      "\206]"
      "\005\317\363\0300\024\313\n\376\255gA\340\202\026\320mE\016\274R\345\357"
      "\327$c\377.\021\212[\210\312Z]\021\222\275\363\265\352\241\310t\026\203$"
      "X\002\371\334\a\372\r\236QG\005v\004f\355\240j0\264Q5H\233S\222\000\023~"
      "\260b\'\267\267\023\036\367\245fp\351\354\221\272\277U\377\001\000\000"
      "\000\000\000\000\205\342Q\0369\335B\335z*v\177 "
      "\316gg\206G\356\252\257zW\246>\221\221\005s\321",
      385);
  syscall(__NR_openat, 0xffffff9c, 0x20000440, 0x275a, 0);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 4; procid++) {
    if (fork() == 0) {
      loop();
    }
  }
  sleep(1000000);
  return 0;
}