INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added 'ci-upstream-net-kasan-gce-4,10.128.15.199' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 executing program syzkaller login: [ 41.107485] ------------[ cut here ]------------ [ 41.108240] WARNING: CPU: 0 PID: 2986 at drivers/net/tun.c:1744 tun_get_user+0x2de3/0x36d0 [ 41.109434] Kernel panic - not syncing: panic_on_warn set ... [ 41.109434] [ 41.110406] CPU: 0 PID: 2986 Comm: syzkaller914043 Not tainted 4.14.0-rc4+ #80 [ 41.111375] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.112600] Call Trace: [ 41.112963] dump_stack+0x194/0x257 [ 41.113457] ? arch_local_irq_restore+0x53/0x53 [ 41.114094] panic+0x1e4/0x417 [ 41.114529] ? __warn+0x1d9/0x1d9 [ 41.114996] ? show_regs_print_info+0x65/0x65 [ 41.115611] ? tun_get_user+0x2de3/0x36d0 [ 41.116167] __warn+0x1c4/0x1d9 [ 41.116614] ? tun_get_user+0x2de3/0x36d0 [ 41.117174] report_bug+0x211/0x2d0 [ 41.117671] fixup_bug+0x40/0x90 [ 41.118132] do_trap+0x260/0x390 [ 41.118599] do_error_trap+0x120/0x390 [ 41.119127] ? kfree_skbmem+0xe2/0x1d0 [ 41.119653] ? do_trap+0x390/0x390 [ 41.120132] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 41.120778] ? tun_get_user+0x2de3/0x36d0 [ 41.121359] ? wait_for_completion+0x7b0/0x7b0 [ 41.121980] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.122632] do_invalid_op+0x1b/0x20 [ 41.123134] invalid_op+0x18/0x20 [ 41.123602] RIP: 0010:tun_get_user+0x2de3/0x36d0 [ 41.124235] RSP: 0018:ffff8801ce42f730 EFLAGS: 00010286 [ 41.124952] RAX: dffffc0000000000 RBX: ffff8801ce25fc98 RCX: dffffc0000000000 [ 41.125906] RDX: ffffffff87062d20 RSI: 0000000000000000 RDI: ffffed0039c85ea8 [ 41.126862] RBP: ffff8801ce42fae0 R08: 0000000000000090 R09: 0000000000000000 [ 41.127822] R10: ffffffff870aaea0 R11: 0000000000000000 R12: ffff8801cf5a83c0 [ 41.135062] R13: ffff8801ce25fd08 R14: 0000000000000000 R15: ffff8801ce1e8dc0 [ 41.142340] ? tun_build_skb.isra.48+0x16e0/0x16e0 [ 41.147241] ? mmap_region+0x7ee/0x15a0 [ 41.151211] ? tun_chr_close+0x60/0x60 [ 41.155077] ? lock_release+0xd70/0xd70 [ 41.159024] ? __lock_is_held+0xbc/0x140 [ 41.163065] ? tun_get+0x1d4/0x2e0 [ 41.166575] ? tun_chr_close+0x60/0x60 [ 41.170430] ? __check_object_size+0x25d/0x4f0 [ 41.174988] tun_chr_write_iter+0xbf/0x160 [ 41.179194] do_iter_readv_writev+0x531/0x7f0 [ 41.183663] ? vfs_dedupe_file_range+0x900/0x900 [ 41.188393] ? rw_verify_area+0xe5/0x2b0 [ 41.192426] do_iter_write+0x15a/0x540 [ 41.196285] ? dup_iter+0x260/0x260 [ 41.199893] vfs_writev+0x18a/0x340 [ 41.203488] ? __fget_light+0x29d/0x390 [ 41.207436] ? vfs_iter_write+0xb0/0xb0 [ 41.211379] ? up_read+0x1a/0x40 [ 41.214714] ? __do_page_fault+0x3d6/0xd60 [ 41.218915] ? security_mmap_file+0x143/0x180 [ 41.223387] ? mm_fault_error+0x2c0/0x2c0 [ 41.227513] ? __fdget_pos+0x136/0x1a0 [ 41.231369] ? __fdget_raw+0x20/0x20 [ 41.235055] ? __do_page_fault+0xd60/0xd60 [ 41.239262] do_writev+0xfc/0x2a0 [ 41.242681] ? do_writev+0xfc/0x2a0 [ 41.246282] ? vfs_writev+0x340/0x340 [ 41.250049] ? entry_SYSCALL_64_fastpath+0x5/0xbe [ 41.254861] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.259850] SyS_writev+0x27/0x30 [ 41.263276] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 41.267998] RIP: 0033:0x4449e0 [ 41.271157] RSP: 002b:00007fff5f3922a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 [ 41.278834] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004449e0 [ 41.286070] RDX: 0000000000000002 RSI: 00007fff5f3922b0 RDI: 0000000000000003 [ 41.293310] RBP: 0000000000000086 R08: 0000000000000018 R09: 0000000000000004 [ 41.300547] R10: 000000000007adef R11: 0000000000000246 R12: 00000000004020f0 [ 41.307784] R13: 0000000000402180 R14: 0000000000000000 R15: 0000000000000000 [ 41.315456] Dumping ftrace buffer: [ 41.318996] (ftrace buffer empty) [ 41.322676] Kernel Offset: disabled [ 41.326279] Rebooting in 86400 seconds..