[io-uring] WARNING in __put_task_struct

[chase xd <sl1589472800@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 4573 bytes --]

Dear Linux kernel maintainers,

Syzkaller reports this previously unknown bug on Linux
6.8.0-rc3-00043-ga69d20885494-dirty #4. Seems like the bug was
silently or unintendedly fixed in the latest version.

I found a similar bug report
[here](https://syzkaller.appspot.com/bug?id=ac425cc8dcf667de21cbe25208555a346ab658d0),
but I think this should be a different bug?

```
Syzkaller hit 'WARNING in __put_task_struct' bug.

------------[ cut here ]------------
WARNING: CPU: 2 PID: 10662 at kernel/fork.c:967
__put_task_struct+0x290/0x340 kernel/fork.c:967
Modules linked in:
CPU: 2 PID: 10662 Comm: syz-executor389 Not tainted
6.8.0-rc3-00043-ga69d20885494-dirty #52
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:__put_task_struct+0x290/0x340 kernel/fork.c:967
Code: da ff ff 48 8b 3d b0 28 69 0f 4c 89 e6 e8 88 d2 7b 00 e9 45 ff
ff ff be 03 00 00 00 4c 89 e7 e8 46 be c7 02 e9 33 ff ff ff 90 <0f> 0b
90 e9 ac fd ff ff 90 0f 0b 90 e9 e9 fd ff ff 90 0f 0b 90 e9
RSP: 0018:ffffc90017f67b38 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 1ffff92002fecf6f RCX: 1ffff92002fecf36
RDX: 1ffff1100e71a530 RSI: ffffffff8a0bdce0 RDI: ffff8880738d2980
RBP: ffff8880738d2440 R08: 0000000000000000 R09: fffffbfff23d9a15
R10: ffffffff91ecd0af R11: 0000000000000000 R12: ffffffff840b8886
R13: ffff8880738d2468 R14: ffff888024ad7818 R15: ffff8880738d2440
FS:  0000555557445480(0000) GS:ffff8880b9880000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff010cdf0b0 CR3: 0000000032094000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
 <TASK>
 put_task_struct include/linux/sched/task.h:138 [inline]
 io_wq_exit_workers io_uring/io-wq.c:1274 [inline]
 io_wq_put_and_exit+0x765/0x8f0 io_uring/io-wq.c:1296
 io_uring_clean_tctx+0x10e/0x190 io_uring/tctx.c:193
 io_uring_cancel_generic+0x643/0x7c0 io_uring/io_uring.c:3395
 io_uring_files_cancel include/linux/io_uring.h:21 [inline]
 do_exit+0x4bf/0x25a0 kernel/exit.c:829
 do_group_exit+0xb4/0x250 kernel/exit.c:1020
 __do_sys_exit_group kernel/exit.c:1031 [inline]
 __se_sys_exit_group kernel/exit.c:1029 [inline]
 __x64_sys_exit_group+0x39/0x40 kernel/exit.c:1029
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd8/0x270 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6f/0x77
RIP: 0033:0x7ff010c59031
Code: b8 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 16 66 0f 1f 84 00
00 00 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d
00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00
RSP: 002b:00007ffd577fbfb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ff010cde1f0 RCX: 00007ff010c59031
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffffffffffb8 R09: 000000000000ffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff010cde1f0
R13: 0000000000000000 R14: 00007ff010cdec80 R15: 00007ff010c13500
 </TASK>


Syzkaller reproducer:
# {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1
Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false
NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false
KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false
Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false
HandleSegv:true Repro:false Trace:false LegacyOptions:{Collide:false
Fault:false FaultCall:0 FaultNth:0}}
r0 = syz_io_uring_setup(0x6e47, &(0x7f0000000000)={0x0, 0x8847, 0x80,
0x4000003, 0x3d6}, &(0x7f0000000080)=<r1=>0x0,
&(0x7f00000000c0)=<r2=>0x0)
open(&(0x7f0000000100)='./file0\x00', 0x2041, 0x8)
r3 = open$dir(&(0x7f0000000140)='./file0\x00', 0x680400, 0x104)
r4 = socket(0x28, 0x80000, 0x89)
epoll_create1(0x80000)
eventfd2(0x802, 0x80800)
syz_io_uring_submit(r1, r2,
&(0x7f0000000340)=@IORING_OP_SEND_ZC={0x2f, 0x1c, 0x1, @sock=r4,
&(0x7f0000000240)=@tipc=@name={0x1e, 0x2, 0x1, {{0x41, 0x4}, 0x3}},
&(0x7f00000002c0)=""/82, 0x52, 0x200, 0x1, 0x101, 0x0, {0x100}})
io_uring_enter(r0, 0x1, 0x1, 0x11, &(0x7f0000000380), 0x8)
syz_io_uring_complete(r1, &(0x7f0000000400))
io_uring_register$IORING_REGISTER_ENABLE_RINGS(r0, 0xc, 0x0, 0x0)
syz_io_uring_submit(r1, r2,
&(0x7f0000000180)=@IORING_OP_ASYNC_CANCEL={0xe, 0x1, 0x0, 0x0, 0x0,
0x1, 0x0, 0x4, 0x1})
syz_io_uring_submit(r1, r2, 0x0)
syz_io_uring_submit(r1, r2,
&(0x7f0000000680)=@IORING_OP_UNLINKAT={0x24, 0x50, 0x0, @fd_dir=r3,
0x0, &(0x7f0000000500)='./file0\x00'})
io_uring_enter(r0, 0x3, 0x3, 0xb, 0x0, 0x0)
syz_io_uring_complete(r1, 0x0)
```

crepro is in the attachment.

Best Regards
Xdchase

[-- Attachment #2: repro.c --]
[-- Type: application/octet-stream, Size: 17553 bytes --]

// 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/mman.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_io_uring_enter
#define __NR_io_uring_enter 426
#endif
#ifndef __NR_io_uring_register
#define __NR_io_uring_register 427
#endif
#ifndef __NR_io_uring_setup
#define __NR_io_uring_setup 425
#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;
}

#define SIZEOF_IO_URING_SQE 64
#define SIZEOF_IO_URING_CQE 16
#define SQ_HEAD_OFFSET 0
#define SQ_TAIL_OFFSET 64
#define SQ_RING_MASK_OFFSET 256
#define SQ_RING_ENTRIES_OFFSET 264
#define SQ_FLAGS_OFFSET 276
#define SQ_DROPPED_OFFSET 272
#define CQ_HEAD_OFFSET 128
#define CQ_TAIL_OFFSET 192
#define CQ_RING_MASK_OFFSET 260
#define CQ_RING_ENTRIES_OFFSET 268
#define CQ_RING_OVERFLOW_OFFSET 284
#define CQ_FLAGS_OFFSET 280
#define CQ_CQES_OFFSET 320

// From linux/io_uring.h
struct io_uring_cqe {
  uint64_t user_data;
  uint32_t res;
  uint32_t flags;
};

/* This is x86 specific */
#define read_barrier() __asm__ __volatile__("" ::: "memory")
#define write_barrier() __asm__ __volatile__("" ::: "memory")

struct io_sqring_offsets {
  uint32_t head;
  uint32_t tail;
  uint32_t ring_mask;
  uint32_t ring_entries;
  uint32_t flags;
  uint32_t dropped;
  uint32_t array;
  uint32_t resv1;
  uint64_t resv2;
};

struct io_cqring_offsets {
  uint32_t head;
  uint32_t tail;
  uint32_t ring_mask;
  uint32_t ring_entries;
  uint32_t overflow;
  uint32_t cqes;
  uint64_t resv[2];
};

struct io_uring_params {
  uint32_t sq_entries;
  uint32_t cq_entries;
  uint32_t flags;
  uint32_t sq_thread_cpu;
  uint32_t sq_thread_idle;
  uint32_t features;
  uint32_t resv[4];
  struct io_sqring_offsets sq_off;
  struct io_cqring_offsets cq_off;
};

#define IORING_OFF_SQ_RING 0
#define IORING_OFF_SQES 0x10000000ULL
#define IORING_SETUP_SQE128 (1U << 10)
#define IORING_SETUP_CQE32 (1U << 11)
#define IORING_SETUP_NO_SQARRAY (1U << 16)

static struct io_uring_params* io_uring_p;

static long syz_io_uring_complete(volatile long a0, volatile long a1)
{
  // syzlang: syz_io_uring_complete(ring_ptr ring_ptr)
  // C:       syz_io_uring_complete(char* ring_ptr)
  // It is not checked if the ring is empty
  // Cast to original
  long ring_ptr = a0;
  int* result_fd = (int*)a1;
  // result_fd = (int*)mmap(0, sizeof(int) * (io_uring_p->cq_entries), PROT_READ
  // | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0); result_fd_cnt = (int*)mmap(0,
  // sizeof(int), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON, -1, 0);
  int cnt = 0;
  // head read once
  unsigned cq_head_raw = *(unsigned*)(io_uring_p->cq_off.head + ring_ptr);
  unsigned cq_ring_mask = *(unsigned*)(io_uring_p->cq_off.ring_mask + ring_ptr);
  do {

    read_barrier();
    // tail
    unsigned cq_tail_raw = *(unsigned*)(io_uring_p->cq_off.tail + ring_ptr);
    if (cq_head_raw == cq_tail_raw) {
      break;
    }
    // head != tail, retrieve cq from head
    unsigned cq_head = cq_head_raw & cq_ring_mask;
    struct io_uring_cqe* cqe;
    if ((io_uring_p->flags & IORING_SETUP_CQE32) == 0)
      cqe = (struct io_uring_cqe*)(io_uring_p->cq_off.cqes + ring_ptr +
                                   SIZEOF_IO_URING_CQE * cq_head);
    else
      cqe = (struct io_uring_cqe*)(io_uring_p->cq_off.cqes + ring_ptr +
                                   SIZEOF_IO_URING_CQE * 2 * cq_head);
    // In the descriptions (sys/linux/io_uring.txt), openat and openat2 are
    // passed with a unique range of sqe.user_data (0x12345 and 0x23456) to
    // identify the operations which produces an fd instance. Check
    // cqe.user_data, which should be the same as sqe.user_data for that
    // operation. If it falls in that unique range, return cqe.res as fd.
    // Otherwise, just return an invalid fd.
    if (cqe->user_data == 0x12345 || cqe->user_data == 0x23456)
      result_fd[cnt++] = cqe->res;
    cq_head_raw += 1;
  } while (1);
  *(unsigned*)(io_uring_p->cq_off.head + ring_ptr) = cq_head_raw;
  write_barrier();
  if (cnt == 0) {
    return -1;
  }
  return 0;
}

// Wrapper for io_uring_setup and the subsequent mmap calls that map the ring
// and the sqes
static long syz_io_uring_setup(volatile long a0, volatile long a1,
                               volatile long a2, volatile long a3)
{
  // syzlang: syz_io_uring_setup(entries int32[1:IORING_MAX_ENTRIES], params
  // ptr[inout, io_uring_params], ring_ptr ptr[out, ring_ptr], sqes_ptr ptr[out,
  // sqes_ptr]) fd_io_uring C:       syz_io_uring_setup(uint32_t entries, struct
  // io_uring_params* params, void** ring_ptr_out, void** sqes_ptr_out) //
  // returns uint32_t fd_io_uring Cast to original
  uint32_t entries = (uint32_t)a0;
  struct io_uring_params* setup_params = (struct io_uring_params*)a1;
  void** ring_ptr_out = (void**)a2;
  void** sqes_ptr_out = (void**)a3;
  // Temporarily disable IORING_SETUP_CQE32 and IORING_SETUP_SQE128 that may
  // change SIZEOF_IO_URING_CQE and SIZEOF_IO_URING_SQE. Tracking bug:
  // https://github.com/google/syzkaller/issues/4531.
  setup_params->flags &= ~(IORING_SETUP_CQE32 | IORING_SETUP_SQE128);
  uint32_t fd_io_uring = syscall(__NR_io_uring_setup, entries, setup_params);
  io_uring_p = setup_params;
  // Compute the ring sizes
  uint32_t sq_ring_sz =
      setup_params->sq_off.array + setup_params->sq_entries * sizeof(uint32_t);
  uint32_t cq_ring_sz = setup_params->cq_off.cqes +
                        setup_params->cq_entries * SIZEOF_IO_URING_CQE;
  // Asssumed IORING_FEAT_SINGLE_MMAP, which is always the case with the current
  // implementation The implication is that the sq_ring_ptr and the cq_ring_ptr
  // are the same but the difference is in the offsets to access the fields of
  // these rings.
  uint32_t ring_sz = sq_ring_sz > cq_ring_sz ? sq_ring_sz : cq_ring_sz;
  *ring_ptr_out =
      mmap(0, ring_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
           fd_io_uring, IORING_OFF_SQ_RING);
  uint32_t sqes_sz = setup_params->sq_entries * SIZEOF_IO_URING_SQE;
  *sqes_ptr_out = mmap(0, sqes_sz, PROT_READ | PROT_WRITE,
                       MAP_SHARED | MAP_POPULATE, fd_io_uring, IORING_OFF_SQES);
  return fd_io_uring;
}

static long syz_io_uring_submit(volatile long a0, volatile long a1,
                                volatile long a2)
{
  // syzlang: syz_io_uring_submit(ring_ptr ring_ptr, sqes_ptr sqes_ptr,
  // sqe ptr[in, io_uring_sqe]) C:       syz_io_uring_submit(char* ring_ptr,
  // io_uring_sqe* sqes_ptr,    io_uring_sqe* sqe) It is not checked if the ring
  // is full Cast to original
  long ring_ptr = a0; // This will be exposed to offsets in bytes
  char* sqes_ptr = (char*)a1;
  char* sqe = (char*)a2;
  unsigned sq_tail_raw = *(unsigned*)(io_uring_p->sq_off.tail + ring_ptr);
  unsigned sq_ring_mask = *(unsigned*)(io_uring_p->sq_off.ring_mask + ring_ptr);
  unsigned sq_tail = sq_tail_raw & sq_ring_mask;
  // write to current sq tail sqe
  void* sqe_dest;
  if ((io_uring_p->flags & IORING_SETUP_SQE128) == 0)
    sqe_dest = (void*)(sqes_ptr + SIZEOF_IO_URING_SQE * sq_tail);
  else {
    sqe_dest = (void*)(sqes_ptr + SIZEOF_IO_URING_SQE * sq_tail * 2);
  }

  // Write the sqe entry to its destination in sqes
  memcpy(sqe_dest, sqe, SIZEOF_IO_URING_SQE);
  // Advance the tail. Tail is a free-flowing integer and relies on natural
  // wrapping. Ensure that the kernel will never see a tail update without the
  // preceeding SQE stores being done.
  __atomic_store_n((unsigned*)(io_uring_p->sq_off.tail + ring_ptr),
                   sq_tail_raw + 1, __ATOMIC_RELEASE);
  // update sq array
  if ((io_uring_p->flags & IORING_SETUP_NO_SQARRAY) == 0)
    __atomic_store_n((unsigned*)(io_uring_p->sq_off.array + ring_ptr) + sq_tail,
                     sq_tail, __ATOMIC_RELEASE);
  // Now the application is free to call io_uring_enter() to submit the sqe
  return 0;
}

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 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 (;;) {
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      sleep_ms(1);
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
  }
}

uint64_t r[5] = {0x0, 0x0, 0x0, 0xffffffffffffff9c, 0x0};

void execute_one(void)
{
  intptr_t res = 0;
  NONFAILING(*(uint32_t*)0x20000004 = 0x8847);
  NONFAILING(*(uint32_t*)0x20000008 = 0x80);
  NONFAILING(*(uint32_t*)0x2000000c = 0x4000003);
  NONFAILING(*(uint32_t*)0x20000010 = 0x3d6);
  NONFAILING(*(uint32_t*)0x20000018 = 0);
  NONFAILING(memset((void*)0x2000001c, 0, 12));
  res = -1;
  NONFAILING(res = syz_io_uring_setup(/*entries=*/0x6e47, /*params=*/0x20000000,
                                      /*ring_ptr=*/0x20000080,
                                      /*sqes_ptr=*/0x200000c0));
  if (res != -1) {
    r[0] = res;
    NONFAILING(r[1] = *(uint64_t*)0x20000080);
    NONFAILING(r[2] = *(uint64_t*)0x200000c0);
  }
  NONFAILING(memcpy((void*)0x20000100, "./file0\000", 8));
  syscall(__NR_open, /*file=*/0x20000100ul,
          /*flags=O_CREAT|FASYNC|O_WRONLY*/ 0x2041ul, /*mode=S_IXGRP*/ 8ul);
  NONFAILING(memcpy((void*)0x20000140, "./file0\000", 8));
  res = syscall(__NR_open, /*file=*/0x20000140ul,
                /*flags=__O_TMPFILE|O_PATH|O_CLOEXEC|O_APPEND*/ 0x680400ul,
                /*mode=S_IROTH|S_IRUSR*/ 0x104ul);
  if (res != -1)
    r[3] = res;
  res = syscall(__NR_socket, /*domain=AF_VSOCK*/ 0x28ul,
                /*type=SOCK_CLOEXEC*/ 0x80000ul, /*proto=*/0x89);
  if (res != -1)
    r[4] = res;
  syscall(__NR_epoll_create1, /*flags=EPOLL_CLOEXEC*/ 0x80000ul);
  syscall(__NR_eventfd2, /*initval=*/0x802,
          /*flags=EFD_NONBLOCK|EFD_CLOEXEC*/ 0x80800ul);
  NONFAILING(*(uint8_t*)0x20000340 = 0x2f);
  NONFAILING(*(uint8_t*)0x20000341 = 0x1c);
  NONFAILING(*(uint16_t*)0x20000342 = 1);
  NONFAILING(*(uint32_t*)0x20000344 = r[4]);
  NONFAILING(*(uint64_t*)0x20000348 = 0x20000240);
  NONFAILING(*(uint16_t*)0x20000240 = 0x1e);
  NONFAILING(*(uint8_t*)0x20000242 = 2);
  NONFAILING(*(uint8_t*)0x20000243 = 1);
  NONFAILING(*(uint32_t*)0x20000244 = 0x41);
  NONFAILING(*(uint32_t*)0x20000248 = 4);
  NONFAILING(*(uint32_t*)0x2000024c = 3);
  NONFAILING(*(uint64_t*)0x20000350 = 0x200002c0);
  NONFAILING(*(uint32_t*)0x20000358 = 0x52);
  NONFAILING(*(uint32_t*)0x2000035c = 0x200);
  NONFAILING(*(uint64_t*)0x20000360 = 1);
  NONFAILING(*(uint16_t*)0x20000368 = 0x101);
  NONFAILING(*(uint16_t*)0x2000036a = 0);
  NONFAILING(*(uint16_t*)0x2000036c = 0x100);
  NONFAILING(*(uint16_t*)0x2000036e = 0);
  NONFAILING(memset((void*)0x20000370, 0, 16));
  NONFAILING(syz_io_uring_submit(/*ring_ptr=*/r[1], /*sqes_ptr=*/r[2],
                                 /*sqe=*/0x20000340));
  NONFAILING(*(uint64_t*)0x20000380 = 0);
  syscall(__NR_io_uring_enter, /*fd=*/r[0], /*to_submit=*/1, /*min_complete=*/1,
          /*flags=IORING_ENTER_REGISTERED_RING|IORING_ENTER_GETEVENTS*/ 0x11ul,
          /*sigmask=*/0x20000380ul, /*size=*/8ul);
  NONFAILING(
      syz_io_uring_complete(/*ring_ptr=*/r[1], /*result_fd=*/0x20000400));
  syscall(__NR_io_uring_register, /*fd=*/r[0], /*opcode=*/0xcul, /*arg=*/0ul,
          /*nr_args=*/0ul);
  NONFAILING(*(uint8_t*)0x20000180 = 0xe);
  NONFAILING(*(uint8_t*)0x20000181 = 1);
  NONFAILING(*(uint16_t*)0x20000182 = 0);
  NONFAILING(*(uint32_t*)0x20000184 = 0);
  NONFAILING(*(uint64_t*)0x20000188 = 0);
  NONFAILING(*(uint64_t*)0x20000190 = 1);
  NONFAILING(*(uint32_t*)0x20000198 = 0);
  NONFAILING(*(uint32_t*)0x2000019c = 4);
  NONFAILING(*(uint64_t*)0x200001a0 = 1);
  NONFAILING(*(uint16_t*)0x200001a8 = 0);
  NONFAILING(*(uint16_t*)0x200001aa = 0);
  NONFAILING(memset((void*)0x200001ac, 0, 4));
  NONFAILING(memset((void*)0x200001b0, 0, 16));
  NONFAILING(syz_io_uring_submit(/*ring_ptr=*/r[1], /*sqes_ptr=*/r[2],
                                 /*sqe=*/0x20000180));
  NONFAILING(
      syz_io_uring_submit(/*ring_ptr=*/r[1], /*sqes_ptr=*/r[2], /*sqe=*/0));
  NONFAILING(*(uint8_t*)0x20000680 = 0x24);
  NONFAILING(*(uint8_t*)0x20000681 = 0x50);
  NONFAILING(*(uint16_t*)0x20000682 = 0);
  NONFAILING(*(uint32_t*)0x20000684 = r[3]);
  NONFAILING(*(uint64_t*)0x20000688 = 0);
  NONFAILING(*(uint64_t*)0x20000690 = 0x20000500);
  NONFAILING(memcpy((void*)0x20000500, "./file0\000", 8));
  NONFAILING(*(uint32_t*)0x20000698 = 0);
  NONFAILING(*(uint32_t*)0x2000069c = 0);
  NONFAILING(*(uint64_t*)0x200006a0 = 0);
  NONFAILING(*(uint16_t*)0x200006a8 = 0);
  NONFAILING(*(uint16_t*)0x200006aa = 0);
  NONFAILING(memset((void*)0x200006ac, 0, 4));
  NONFAILING(memset((void*)0x200006b0, 0, 16));
  NONFAILING(syz_io_uring_submit(/*ring_ptr=*/r[1], /*sqes_ptr=*/r[2],
                                 /*sqe=*/0x20000680));
  syscall(
      __NR_io_uring_enter, /*fd=*/r[0], /*to_submit=*/3, /*min_complete=*/3,
      /*flags=IORING_ENTER_EXT_ARG|IORING_ENTER_SQ_WAKEUP|IORING_ENTER_GETEVENTS*/
      0xbul, /*sigmask=*/0ul, /*size=*/0ul);
  NONFAILING(syz_io_uring_complete(/*ring_ptr=*/r[1], /*result_fd=*/0));
}
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);
  install_segv_handler();
  loop();
  return 0;
}