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-mmots-kasan-gce-5,10.128.0.50' (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: [ 34.170134] ------------[ cut here ]------------ [ 34.175547] WARNING: CPU: 0 PID: 2979 at drivers/net/tun.c:1744 tun_get_user+0x2de3/0x36d0 [ 34.184224] Kernel panic - not syncing: panic_on_warn set ... [ 34.184224] [ 34.191563] CPU: 0 PID: 2979 Comm: syzkaller282635 Not tainted 4.14.0-rc4-mm1+ #16 [ 34.199241] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.208571] Call Trace: [ 34.211137] dump_stack+0x194/0x257 [ 34.214744] ? arch_local_irq_restore+0x53/0x53 [ 34.219400] panic+0x1e4/0x41c [ 34.222571] ? refcount_error_report+0x214/0x214 [ 34.227299] ? show_regs_print_info+0x65/0x65 [ 34.231783] ? tun_get_user+0x2de3/0x36d0 [ 34.235905] __warn+0x1c4/0x1e0 [ 34.239157] ? tun_get_user+0x2de3/0x36d0 [ 34.243283] report_bug+0x211/0x2d0 [ 34.246891] fixup_bug+0x40/0x90 [ 34.250230] do_trap+0x260/0x390 [ 34.253576] do_error_trap+0x120/0x390 [ 34.257447] ? kfree_skbmem+0xe2/0x1d0 [ 34.261314] ? do_trap+0x390/0x390 [ 34.264826] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 34.269641] ? tun_get_user+0x2de3/0x36d0 [ 34.273766] ? wait_for_completion+0x7b0/0x7b0 [ 34.278325] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 34.283145] do_invalid_op+0x1b/0x20 [ 34.286833] invalid_op+0x18/0x20 [ 34.290259] RIP: 0010:tun_get_user+0x2de3/0x36d0 [ 34.294985] RSP: 0018:ffff8801ce03f730 EFLAGS: 00010286 [ 34.300323] RAX: dffffc0000000000 RBX: ffff8801ceb645d8 RCX: dffffc0000000000 [ 34.307565] RDX: ffffffff86e2ace0 RSI: 0000000000000000 RDI: ffffed0039c07ea8 [ 34.315068] RBP: ffff8801ce03fae0 R08: 0000000000000080 R09: 0000000000000000 [ 34.322306] R10: ffffffff86e71a60 R11: 0000000000000000 R12: ffff8801cd7418c0 [ 34.329546] R13: ffff8801ceb64648 R14: 0000000000000000 R15: ffff8801ce170dc0 [ 34.336828] ? tun_build_skb.isra.48+0x16e0/0x16e0 [ 34.341732] ? do_mmap+0x6a1/0xd50 [ 34.345272] ? tun_chr_close+0x60/0x60 [ 34.349138] ? lock_release+0xd70/0xd70 [ 34.353088] ? __lock_is_held+0xbc/0x140 [ 34.357133] ? tun_get+0x1d4/0x2e0 [ 34.360645] ? tun_chr_close+0x60/0x60 [ 34.364504] ? __check_object_size+0x25d/0x4f0 [ 34.369065] tun_chr_write_iter+0xbf/0x160 [ 34.373273] do_iter_readv_writev+0x531/0x7f0 [ 34.377745] ? vfs_dedupe_file_range+0x900/0x900 [ 34.382477] ? rw_verify_area+0xe5/0x2b0 [ 34.386511] do_iter_write+0x15a/0x540 [ 34.390370] ? dup_iter+0x260/0x260 [ 34.393977] vfs_writev+0x18a/0x340 [ 34.397577] ? __fget_light+0x29d/0x390 [ 34.401528] ? vfs_iter_write+0xb0/0xb0 [ 34.405476] ? up_read+0x1a/0x40 [ 34.408823] ? __do_page_fault+0x3d6/0xd60 [ 34.413029] ? security_mmap_file+0x143/0x180 [ 34.417505] ? mm_fault_error+0x2c0/0x2c0 [ 34.421635] ? __fdget_pos+0x136/0x1a0 [ 34.425496] ? __fdget_raw+0x20/0x20 [ 34.429187] ? __do_page_fault+0xd60/0xd60 [ 34.433400] do_writev+0xfc/0x2a0 [ 34.436829] ? do_writev+0xfc/0x2a0 [ 34.440438] ? vfs_writev+0x340/0x340 [ 34.444211] ? entry_SYSCALL_64_fastpath+0x5/0xbe [ 34.449028] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.454029] SyS_writev+0x27/0x30 [ 34.457456] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.462185] RIP: 0033:0x444b10 [ 34.465348] RSP: 002b:00007ffde0023708 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 [ 34.473030] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000444b10 [ 34.480273] RDX: 0000000000000002 RSI: 00007ffde0023710 RDI: 0000000000000003 [ 34.487518] RBP: 0000000000000082 R08: 000000000000003e R09: 0000000000000004 [ 34.494761] R10: 00000000aaaaaaaa R11: 0000000000000246 R12: 0000000000402220 [ 34.502001] R13: 00000000004022b0 R14: 0000000000000000 R15: 0000000000000000 [ 34.509440] Dumping ftrace buffer: [ 34.513023] (ftrace buffer empty) [ 34.516709] Kernel Offset: disabled [ 34.520321] Rebooting in 86400 seconds..