// https://syzkaller.appspot.com/bug?id=850d61635c17651d0a8bd3e64c149856ec2dafea
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.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/prctl.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#ifndef __NR_memfd_create
#define __NR_memfd_create 319
#endif

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 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 int inject_fault(int nth)
{
  int fd;
  fd = open("/proc/thread-self/fail-nth", O_RDWR);
  if (fd == -1)
    exit(1);
  char buf[16];
  sprintf(buf, "%d", nth);
  if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf))
    exit(1);
  return fd;
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  for (int 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) {
  }
}

static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  write_file("/proc/self/oom_score_adj", "1000");
}

static const char* setup_fault()
{
  int fd = open("/proc/self/make-it-fail", O_WRONLY);
  if (fd == -1)
    return "CONFIG_FAULT_INJECTION is not enabled";
  close(fd);
  fd = open("/proc/thread-self/fail-nth", O_WRONLY);
  if (fd == -1)
    return "kernel does not have systematic fault injection support";
  close(fd);
  static struct {
    const char* file;
    const char* val;
    bool fatal;
  } files[] = {
      {"/sys/kernel/debug/failslab/ignore-gfp-wait", "N", true},
      {"/sys/kernel/debug/fail_futex/ignore-private", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/min-order", "0", false},
  };
  unsigned i;
  for (i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].file, files[i].val)) {
      if (files[i].fatal)
        return "failed to write fault injection file";
    }
  }
  return NULL;
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter = 0;
  for (;; iter++) {
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      setup_test();
      execute_one();
      exit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      sleep_ms(10);
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
  }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_one(void)
{
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  NONFAILING(memcpy(
      (void*)0x20000540,
      "\001\375\256.+\246\214\266?2\0319\224S,|x?Ue[\275\341!\0033\274\'#"
      "\377\027\233%\363[d "
      "\006\000\000\000\227A\302\330\360Uq!\344\304\261\242\034\377C;"
      "\224Q\r\266}\234\354C\v\317\353\344\232R\345,"
      "\202\003\000\031\215\350\306\271\344\264\231\212\031P\270\214x\b\231\004"
      "R\005\257\242\3525\f\314\032\233\000Uf\245\367\200Tgiz\nX\b\221\3750\216"
      "\266\243\v#\026\337\264\300\346\264\357\250i\330\242\322("
      "\230\233A\217\023\353\364b/"
      "\357!\217\366]-"
      "\361k\2662\211gEv\023\364\307\262\365\\\027\220\265\246\250\270o\017\342"
      " \347\234$\327\362@\367cdv[\t\000\215\363\3141\r$"
      "\036\377\360P\262\227\270\274\353\221\207\213u\277\324\'\377\037\f\0016"
      "\235Q\356T\350\bY\000\262\006\246\276l\233."
      "o\276\200\235x\325O\326h\\I\311\215\a\035\311k\203\374\244\2554\003\242X"
      "\017\202\333s\307\203L\236\242\321\263\254\215\330\264\264\352\220Q\330"
      "\307\353%"
      "\213Op\032b\226\317\273\025\317\374N\355\000\000\000\000\000\000\000\000"
      "\000\000\000\000\000s\257\242\024]p+\226\036i|n\332\356\\\256\226*\202*"
      "\270j\332\252\024\037\035\370\370\256\374H\304\263j\350\317O\357\016\257"
      "e\265*"
      "\211\030\262w\226\b\033y\352T\335\263g6\274\205\262Y\314v\006\000\000"
      "\000\305e\220\3051\237\v_# "
      "\b\245\274P,|\351\326s\037\037\276\323\200\261\250 "
      "\316|df\2203\v\002\352.\003X\265\344,"
      "8\267\255EI\334A\247\314\327\371n\033\225\370\021Z\346:"
      "\003\316\376\002\214tdy~_oC\236\357\360\242K\351;\216:"
      "\001\003C\222\353\026\034\277\276\357\314Uxhg\337Y\346\203\246z\377\001"
      "\235 o_{!O\252jU\204 "
      "\351\2659r\234w\030Z\323\315\016\272\\\333\360\341\206\t\257\vi\334\277?"
      "\365\n\275^\005\300\316uC}\250\307\255\206\327\025&\271]"
      "1\005J\226\360\204\301\f\246p\226?"
      "\000\000\000\000\000\000\000\022\210\310\234\311Cn\324\2447V\'+"
      "\314\277\r\251\020\035\317\353Klb\345:"
      "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000G\337\273"
      "\300_\231F\364n]"
      "\024\274\315\323\237\237e\305\346\350Mb\306\202\202\313\312Xe\341\242"
      "\252\002\206\270\030\342C\353\251\027&\001&"
      "\'w\241t0\200\360\223\200\237\233\340\237\352\271\236D]#"
      "V\332\222\312\306\372."
      "\326\3431\376\350\002\353X\275\nz\001O\323r\242\251u\223>"
      "m\327q\'\337\372jo\330n\247\354Ji\336\337\177\343\304*Z "
      "4\350S$\241H="
      "\337\005\363\343T\321\335\306f\244\264\226\\\240\371\017\027\021{"
      "\266\235\3221\301\220Vj\023r\000\000\336\003\253\377\212s0\306E\312\""
      "\331*\232\025\2715r\217\252j\202\326\322%"
      "\355\242WQ\3542\000\000\000\000\000\000\000\000\000\000\000\000\314X\375"
      "RB\377U\351\372\037\366\316\b\336@\0061\306z\344\340\311?\247\224>"
      "\234\321\245o\004\252im\256\376\307f\243\226\327\264c)r{\r#\335I&"
      "\n\362\354\324\377\237\0236zZ-2\200\373H+\2338\363\355\337\242my\2628c["
      "\303\376\265M\204\227\245\'s\351\334=)I\253Lt2\234\v\331S",
      887));
  res = syscall(__NR_memfd_create, /*name=*/0x20000540ul,
                /*flags=MFD_HUGETLB|MFD_ALLOW_SEALING*/ 6ul);
  if (res != -1)
    r[0] = res;
  syscall(__NR_fallocate, /*fd=*/r[0], /*mode=*/0ul, /*off=*/0ul,
          /*len=*/0x400ul);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x3000ul,
          /*prot=PROT_READ|PROT_EXEC*/ 5ul,
          /*flags=MAP_FIXED|MAP_PRIVATE*/ 0x12ul, /*fd=*/r[0], /*offset=*/0ul);
  NONFAILING(*(uint64_t*)0x20000140 = 8);
  NONFAILING(*(uint64_t*)0x20000148 = 0x88);
  syscall(__NR_prlimit64, /*pid=*/0, /*res=RLIMIT_RTPRIO*/ 0xeul,
          /*new=*/0x20000140ul, /*old=*/0ul);
  inject_fault(14);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0xb36000ul,
          /*prot=PROT_GROWSUP|PROT_SEM|PROT_WRITE|PROT_EXEC|0xb635773f04ebbee0*/
          0xb635773f06ebbeeeul,
          /*flags=MAP_POPULATE|MAP_FIXED|MAP_ANONYMOUS|MAP_SHARED*/ 0x8031ul,
          /*fd=*/-1, /*offset=*/0ul);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  const char* reason;
  (void)reason;
  if ((reason = setup_fault()))
    printf("the reproducer may not work as expected: fault injection setup "
           "failed: %s\n",
           reason);
  install_segv_handler();
  loop();
  return 0;
}