1*8a272653SPeter Holm#!/bin/sh 2*8a272653SPeter Holm 3*8a272653SPeter Holm# panic: Assertion *buflen >= 2 failed at ../../../kern/vfs_cache.c:2837 4*8a272653SPeter Holm# cpuid = 21 5*8a272653SPeter Holm# time = 1598296274 6*8a272653SPeter Holm# KDB: stack backtrace: 7*8a272653SPeter Holm# db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xfffffe0149a9e860 8*8a272653SPeter Holm# vpanic() at vpanic+0x182/frame 0xfffffe0149a9e8b0 9*8a272653SPeter Holm# panic() at panic+0x43/frame 0xfffffe0149a9e910 10*8a272653SPeter Holm# vn_fullpath_any_smr() at vn_fullpath_any_smr+0x4df/frame 0xfffffe0149a9e980 11*8a272653SPeter Holm# sys___realpathat() at sys___realpathat+0x20b/frame 0xfffffe0149a9ead0 12*8a272653SPeter Holm# amd64_syscall() at amd64_syscall+0x159/frame 0xfffffe0149a9ebf0 13*8a272653SPeter Holm# fast_syscall_common() at fast_syscall_common+0xf8/frame 0xfffffe0149a9ebf0 14*8a272653SPeter Holm# --- syscall (0, FreeBSD ELF64, nosys), rip = 0x8004294ea, rsp = 0x7fffffffe548, rbp = 0x7fffffffe580 --- 15*8a272653SPeter Holm# KDB: enter: panic 16*8a272653SPeter Holm# [ thread pid 2831 tid 100306 ] 17*8a272653SPeter Holm# Stopped at kdb_enter+0x37: movq $0,0x10b4246(%rip) 18*8a272653SPeter Holm# db> x/s version 19*8a272653SPeter Holm# version: FreeBSD 13.0-CURRENT #0 r364722: Mon Aug 24 21:04:09 CEST 2020 20*8a272653SPeter Holm# pho@t2.osted.lan:/usr/src/sys/amd64/compile/PHO\012 21*8a272653SPeter Holm# db> 22*8a272653SPeter Holm 23*8a272653SPeter Holm[ `uname -p` != "amd64" ] && exit 0 24*8a272653SPeter Holm 25*8a272653SPeter Holm# Obtained from markj (syzkaller). 26*8a272653SPeter Holm# Fixed by r364723. 27*8a272653SPeter Holm 28*8a272653SPeter Holm. ../default.cfg 29*8a272653SPeter Holmkldstat -v | grep -q sctp || kldload sctp.ko 30*8a272653SPeter Holmcat > /tmp/syzkaller22.c <<EOF 31*8a272653SPeter Holm// autogenerated by syzkaller (https://github.com/google/syzkaller) 32*8a272653SPeter Holm 33*8a272653SPeter Holm#define _GNU_SOURCE 34*8a272653SPeter Holm 35*8a272653SPeter Holm#include <pwd.h> 36*8a272653SPeter Holm#include <stdarg.h> 37*8a272653SPeter Holm#include <stdbool.h> 38*8a272653SPeter Holm#include <stdint.h> 39*8a272653SPeter Holm#include <stdio.h> 40*8a272653SPeter Holm#include <stdlib.h> 41*8a272653SPeter Holm#include <string.h> 42*8a272653SPeter Holm#include <sys/endian.h> 43*8a272653SPeter Holm#include <sys/syscall.h> 44*8a272653SPeter Holm#include <unistd.h> 45*8a272653SPeter Holm 46*8a272653SPeter Holmuint64_t r[1] = {0xffffffffffffffff}; 47*8a272653SPeter Holm 48*8a272653SPeter Holmint main(void) 49*8a272653SPeter Holm{ 50*8a272653SPeter Holm syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x1012ul, -1, 0ul); 51*8a272653SPeter Holm intptr_t res = 0; 52*8a272653SPeter Holm memcpy((void*)0x20000000, "./file0\000", 8); 53*8a272653SPeter Holm syscall(SYS_open, 0x20000000ul, 0x200645ul, 0ul); 54*8a272653SPeter Holm memcpy((void*)0x20000000, ".\000", 2); 55*8a272653SPeter Holm res = syscall(SYS_open, 0x20000000ul, 0ul, 0ul); 56*8a272653SPeter Holm if (res != -1) 57*8a272653SPeter Holm r[0] = res; 58*8a272653SPeter Holm memcpy((void*)0x20000240, "./file0\000", 8); 59*8a272653SPeter Holm syscall(SYS___realpathat, r[0], 0x20000240ul, 0x20000280ul, 8ul, 0ul); 60*8a272653SPeter Holm return 0; 61*8a272653SPeter Holm} 62*8a272653SPeter HolmEOF 63*8a272653SPeter Holmmycc -o /tmp/syzkaller22 -Wall -Wextra -O0 /tmp/syzkaller22.c || 64*8a272653SPeter Holm exit 1 65*8a272653SPeter Holm 66*8a272653SPeter Holm(cd /tmp; timeout 1m ./syzkaller22) 67*8a272653SPeter Holm 68*8a272653SPeter Holmrm -f /tmp/syzkaller22 /tmp/syzkaller22.c /tmp/syzkaller22.core /tmp/file0 69*8a272653SPeter Holmexit 0 70