[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.25' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 27.578486] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.583720] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.592704] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.596628] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.606859] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.623650] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.624152] ip_tables: iptables: counters copy to user failed while replacing table [ 27.640514] ip_tables: iptables: counters copy to user failed while replacing table [ 27.649126] ip_tables: iptables: counters copy to user failed while replacing table [ 27.651904] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.659633] ip_tables: iptables: counters copy to user failed while replacing table [ 27.669007] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.675746] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.686434] ip_tables: iptables: counters copy to user failed while replacing table [ 27.695555] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 27.699092] ip_tables: iptables: counters copy to user failed while replacing table [ 27.715804] ip_tables: iptables: counters copy to user failed while replacing table [ 27.724339] ip_tables: iptables: counters copy to user failed while replacing table [ 27.732470] ip_tables: iptables: counters copy to user failed while replacing table [ 27.741619] ip_tables: iptables: counters copy to user failed while replacing table [ 27.749837] [ 27.751601] ============================= [ 27.755734] WARNING: suspicious RCU usage [ 27.759927] 4.14.249-syzkaller #0 Not tainted [ 27.764422] ----------------------------- [ 27.768555] net/netfilter/nf_queue.c:227 suspicious rcu_dereference_check() usage! [ 27.776294] [ 27.776294] other info that might help us debug this: [ 27.776294] [ 27.784484] [ 27.784484] rcu_scheduler_active = 2, debug_locks = 1 [ 27.791192] 2 locks held by syz-executor599/8001: [ 27.796019] #0: (rcu_callback){....}, at: [] rcu_process_callbacks+0x84e/0x1180 [ 27.805265] #1: (&(&inst->lock)->rlock){+.-.}, at: [] nfqnl_flush+0x2f/0x2a0 [ 27.814248] [ 27.814248] stack backtrace: [ 27.818742] CPU: 0 PID: 8001 Comm: syz-executor599 Not tainted 4.14.249-syzkaller #0 [ 27.826615] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.835957] Call Trace: [ 27.838527] [ 27.840671] dump_stack+0x1b2/0x281 [ 27.844297] nf_reinject+0x56e/0x700 [ 27.848010] nfqnl_flush+0x1ab/0x2a0 [ 27.851724] instance_destroy_rcu+0x19/0x30 [ 27.856039] ? nfqnl_rcv_nl_event+0x290/0x290 [ 27.860531] rcu_process_callbacks+0x780/0x1180 [ 27.865199] ? note_gp_changes+0x2f0/0x2f0 [ 27.869425] ? sched_clock+0x2a/0x40 [ 27.873137] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 27.878589] __do_softirq+0x24d/0x9ff [ 27.882386] ? check_preemption_disabled+0x35/0x240 [ 27.887397] irq_exit+0x193/0x240 [ 27.890844] smp_apic_timer_interrupt+0x141/0x5e0 [ 27.895683] apic_timer_interrupt+0x93/0xa0 [ 27.899996] [ 27.902322] RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x50 [ 27.907672] RSP: 0018:ffff8880b353faf8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10 [ 27.915371] RAX: 1ffff110166a7531 RBX: ffff8880b353a988 RCX: 1ffffffff126c314 [ 27.922632] RDX: 0000000000000000 RSI: ffffffff87895de0 RDI: ffff8880959a4318 [ 27.929895] RBP: ffff8880959a4300 R08: ffffffff8b9d21a0 R09: 0000000000000000 [ 27.937156] R10: 0000000000000000 R11: ffff8880959a4300 R12: dffffc0000000000 [ 27.944422] R13: ffff8880b3538000 R14: ffff8880b353f680 R15: ffff8880959a4830 [ 27.951698] do_exit+0x153a/0x2850 [ 27.955236] ? wake_up_q+0x82/0xd0 [ 27.958771] ? mm_update_next_owner+0x5b0/0x5b0 [ 27.963487] ? get_signal+0x323/0x1ca0 [ 27.967369] ? lock_downgrade+0x740/0x740 [ 27.971511] do_group_exit+0x100/0x2e0 [ 27.975393] get_signal+0x38d/0x1ca0 [ 27.979099] ? do_futex+0x127/0x1570 [ 27.982812] ? apparmor_file_alloc_security+0x129/0x800 [ 27.988177] do_signal+0x7c/0x1550 [ 27.991719] ? setup_sigcontext+0x820/0x820 [ 27.996036] ? __fd_install+0x227/0x5c0 [ 28.000007] ? get_unused_fd_flags+0xc0/0xc0 [ 28.004406] ? sock_alloc_file+0x1ae/0x2e0 [ 28.008638] ? SyS_futex+0x1da/0x290 [ 28.012340] ? SyS_futex+0x1e3/0x290 [ 28.016049] ? exit_to_usermode_loop+0x41/0x200 [ 28.020715] exit_to_usermode_loop+0x160/0x200 [ 28.025291] do_syscall_64+0x4a3/0x640 [ 28.029175] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 28.034352] RIP: 0033:0x7f5539643289 [ 28.038050] RSP: 002b:00007f55395d22f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 28.045747] RAX: fffffffffffffe00 RBX: 00007f55396cb410 RCX: 00007f5539643289 [ 28.053007] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f55396cb418 [ 28.060263] RBP: 00007f5539699074 R08: 0000000000000000 R09: 0000000000000000 [ 28.067520] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 28.074776] R13: 00000000200007a0 R14: 0001000800000000 R15: 00007f55396cb418 [ 32.576816] nla_parse: 2410 callbacks suppressed [ 32.576820] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.578966] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.582617] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.592188] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.603393] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.614138] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.620396] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.629511] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.636068] net_ratelimit: 2416 callbacks suppressed [ 32.636071] ip_tables: iptables: counters copy to user failed while replacing table [ 32.644230] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.656887] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 32.669912] ip_tables: iptables: counters copy to user failed while replacing table [ 32.690494] ip_tables: iptables: counters copy to user failed while replacing table [ 32.698560] ip_tables: iptables: counters copy to user failed while replacing table [ 32.706858] ip_tables: iptables: counters copy to user failed while replacing table [ 32.715478] ip_tables: iptables: counters copy to user failed while replacing table [ 32.723963] ip_tables: iptables: counters copy to user failed while replacing table [ 32.731988] ip_tables: iptables: counters copy to user failed while replacing table [ 32.740879] ip_tables: iptables: counters copy to user failed while replacing table [ 32.751527] ip_tables: iptables: counters copy to user failed while replacing table [ 37.583900] nla_parse: 2511 callbacks suppressed [ 37.583905] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.585412] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.589365] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.598437] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.609596] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.616873] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.629336] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.648191] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.650817] net_ratelimit: 2513 callbacks suppressed [ 37.650820] ip_tables: iptables: counters copy to user failed while replacing table [ 37.661024] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.666001] netlink: 12 bytes leftover after parsing attributes in process `syz-executor599'. [ 37.674710] ip_tables: iptables: counters copy to user failed while replacing table [ 37.698076] ip_tables: iptables: counters copy to user failed while replacing table [ 37.706521] ip_tables: iptables: counters copy to user failed while replacing table [ 37.715233] ip_tables: iptables: counters copy to user failed while replacing table [ 37.723858] ip_tables: iptables: counters copy to user failed while replacing table