1#!/bin/sh 2 3# panic: mutex Giant owned at ../../../kern/kern_thread.c:1409 4# cpuid = 0 5# time = 1688501618 6# KDB: stack backtrace: 7# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0171ba2510 8# vpanic() at vpanic+0x150/frame 0xfffffe0171ba2560 9# panic() at panic+0x43/frame 0xfffffe0171ba25c0 10# __mtx_assert() at __mtx_assert+0xc4/frame 0xfffffe0171ba25d0 11# thread_suspend_check() at thread_suspend_check+0x38/frame 0xfffffe0171ba2610 12# sig_intr() at sig_intr+0x78/frame 0xfffffe0171ba2640 13# fork1() at fork1+0x238/frame 0xfffffe0171ba26c0 14# kproc_create() at kproc_create+0x92/frame 0xfffffe0171ba2790 15# kproc_kthread_add() at kproc_kthread_add+0xdd/frame 0xfffffe0171ba28b0 16# zthr_create_timer() at zthr_create_timer+0x109/frame 0xfffffe0171ba2930 17# arc_init() at arc_init+0x1b44/frame 0xfffffe0171ba2970 18# dmu_init() at dmu_init+0x31/frame 0xfffffe0171ba2980 19# spa_init() at spa_init+0xed/frame 0xfffffe0171ba29a0 20# zfs_kmod_init() at zfs_kmod_init+0x1f/frame 0xfffffe0171ba29c0 21# zfs_modevent() at zfs_modevent+0module_register_init() at module_register_init+0xb0/frame 0xfffffe0171ba2a10 22# linker_load_module() at linker_load_module+0xbd2/frame 0xfffffe0171ba2d10 23# kern_kldload() at kern_kldload+0x16f/frame 0xfffffe0171ba2d60 24# vfs_byname_kld() at vfs_byname_kld+0x31/frame 0xfffffe0171ba2da0 25# sys_mount() at sys_mount+0xa9/frame 0xfffffe0171ba2e00 26# amd64_syscall() at amd64_syscall+0x150/frame 0xfffffe0171ba2f30 27# fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0171ba2f30 28# --- syscall (0, FreeBSD ELF64, syscall), rip = 0x823f70e9a, rsp = 0x82513af78, rbp = 0x82513af90 KDB: enter: panic 29# [ thread pid 43886 tid 178779 ] 30# Stopped at kdb_enter+0x32: movq $0,0xde5863(%rip) 31# db> x/s version 32# version: FreeBSD 14.0-CURRENT #0 main-n263953-d7614c010c762: Tue Jul 4 19:29:44 CEST 2023 33# pho@mercat1.netperf.freebsd.org:/usr/src/sys/amd64/compile/PHO 34# db> 35 36uname -p | grep -Eq "amd64|i386" || exit 0 37[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1 38 39. ../default.cfg 40prog=$(basename "$0" .sh) 41cat > /tmp/$prog.c <<EOF 42// https://syzkaller.appspot.com/bug?id=85a795d15aa54816d63f71f69bfb3a2c61635472 43// autogenerated by syzkaller (https://github.com/google/syzkaller) 44// Reported-by: syzbot+dce5858451a2329877ff@syzkaller.appspotmail.com 45 46#define _GNU_SOURCE 47 48#include <errno.h> 49#include <pthread.h> 50#include <pwd.h> 51#include <stdarg.h> 52#include <stdbool.h> 53#include <stdint.h> 54#include <stdio.h> 55#include <stdlib.h> 56#include <string.h> 57#include <sys/endian.h> 58#include <sys/syscall.h> 59#include <time.h> 60#include <unistd.h> 61 62static void sleep_ms(uint64_t ms) 63{ 64 usleep(ms * 1000); 65} 66 67static uint64_t current_time_ms(void) 68{ 69 struct timespec ts; 70 if (clock_gettime(CLOCK_MONOTONIC, &ts)) 71 exit(1); 72 return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; 73} 74 75static void thread_start(void* (*fn)(void*), void* arg) 76{ 77 pthread_t th; 78 pthread_attr_t attr; 79 pthread_attr_init(&attr); 80 pthread_attr_setstacksize(&attr, 128 << 10); 81 int i = 0; 82 for (; i < 100; i++) { 83 if (pthread_create(&th, &attr, fn, arg) == 0) { 84 pthread_attr_destroy(&attr); 85 return; 86 } 87 if (errno == EAGAIN) { 88 usleep(50); 89 continue; 90 } 91 break; 92 } 93 exit(1); 94} 95 96typedef struct { 97 pthread_mutex_t mu; 98 pthread_cond_t cv; 99 int state; 100} event_t; 101 102static void event_init(event_t* ev) 103{ 104 if (pthread_mutex_init(&ev->mu, 0)) 105 exit(1); 106 if (pthread_cond_init(&ev->cv, 0)) 107 exit(1); 108 ev->state = 0; 109} 110 111static void event_reset(event_t* ev) 112{ 113 ev->state = 0; 114} 115 116static void event_set(event_t* ev) 117{ 118 pthread_mutex_lock(&ev->mu); 119 if (ev->state) 120 exit(1); 121 ev->state = 1; 122 pthread_mutex_unlock(&ev->mu); 123 pthread_cond_broadcast(&ev->cv); 124} 125 126static void event_wait(event_t* ev) 127{ 128 pthread_mutex_lock(&ev->mu); 129 while (!ev->state) 130 pthread_cond_wait(&ev->cv, &ev->mu); 131 pthread_mutex_unlock(&ev->mu); 132} 133 134static int event_isset(event_t* ev) 135{ 136 pthread_mutex_lock(&ev->mu); 137 int res = ev->state; 138 pthread_mutex_unlock(&ev->mu); 139 return res; 140} 141 142static int event_timedwait(event_t* ev, uint64_t timeout) 143{ 144 uint64_t start = current_time_ms(); 145 uint64_t now = start; 146 pthread_mutex_lock(&ev->mu); 147 for (;;) { 148 if (ev->state) 149 break; 150 uint64_t remain = timeout - (now - start); 151 struct timespec ts; 152 ts.tv_sec = remain / 1000; 153 ts.tv_nsec = (remain % 1000) * 1000 * 1000; 154 pthread_cond_timedwait(&ev->cv, &ev->mu, &ts); 155 now = current_time_ms(); 156 if (now - start > timeout) 157 break; 158 } 159 int res = ev->state; 160 pthread_mutex_unlock(&ev->mu); 161 return res; 162} 163 164struct thread_t { 165 int created, call; 166 event_t ready, done; 167}; 168 169static struct thread_t threads[16]; 170static void execute_call(int call); 171static int running; 172 173static void* thr(void* arg) 174{ 175 struct thread_t* th = (struct thread_t*)arg; 176 for (;;) { 177 event_wait(&th->ready); 178 event_reset(&th->ready); 179 execute_call(th->call); 180 __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); 181 event_set(&th->done); 182 } 183 return 0; 184} 185 186static void loop(void) 187{ 188 int i, call, thread; 189 for (call = 0; call < 1; call++) { 190 for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); 191 thread++) { 192 struct thread_t* th = &threads[thread]; 193 if (!th->created) { 194 th->created = 1; 195 event_init(&th->ready); 196 event_init(&th->done); 197 event_set(&th->done); 198 thread_start(thr, th); 199 } 200 if (!event_isset(&th->done)) 201 continue; 202 event_reset(&th->done); 203 th->call = call; 204 __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); 205 event_set(&th->ready); 206 event_timedwait(&th->done, 50); 207 break; 208 } 209 } 210 for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) 211 sleep_ms(1); 212} 213 214void execute_call(int call) 215{ 216 switch (call) { 217 case 0: 218 memcpy((void*)0x20000440, "zfs\000", 4); 219 syscall(SYS_mount, 0x20000440ul, 0ul, 0x8300648ul, 0ul); 220 break; 221 } 222} 223int main(void) 224{ 225 syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul); 226 loop(); 227 return 0; 228} 229EOF 230mycc -o /tmp/$prog -Wall -Wextra -O0 /tmp/$prog.c -lpthread || exit 1 231 232(cd /tmp; timeout 2m ./$prog) 233 234rm -rf /tmp/$prog /tmp/$prog.c /tmp/syzkaller.* 235exit 0 236