On Mon, 12 Nov 2018, syzbot wrote: > syzbot has found a reproducer for the following crash on: > > HEAD commit: e12e00e388de Merge tag 'kbuild-fixes-v4.20' of git://git.k.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=100e4ef5400000 > kernel config: https://syzkaller.appspot.com/x/.config?x=8f215f21f041a0d7 > dashboard link: https://syzkaller.appspot.com/bug?extid=7634edaea4d0b341c625 > compiler: gcc (GCC) 8.0.1 20180413 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11ce6fbd400000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+7634edaea4d0b341c625@xxxxxxxxxxxxxxxxxxxxxxxxx I tried reproducing this bug on my own system, following the instructions at https://github.com/google/syzkaller/blob/master/docs/executing_syzkaller_programs.md The reproducer failed to run properly. It produced the following output: $ ./syz-execprog -cover=0 -threaded=1 -repeat=1 -procs=4 /tmp/repro.syz 2018/11/13 15:29:32 parsed 1 programs 2018/11/13 15:29:32 executed programs: 0 2018/11/13 15:29:32 result: failed=false hanged=false err=executor 3: failed: tun: ioctl(TUNSETIFF) failed (errno 1) loop failed (errno 0) tun: ioctl(TUNSETIFF) failed (errno 1) loop failed (errno 0) The system is Fedora 28 running the 4.18.16-200.fc28.x86_64 kernel. What should I do to investigate further? Alan Stern
