[....] 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[ 12.748730] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 15.136776] random: sshd: uninitialized urandom read (32 bytes read) [ 15.470943] random: sshd: uninitialized urandom read (32 bytes read) [ 15.959933] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.31' (ECDSA) to the list of known hosts. [ 21.649480] urandom_read: 1 callbacks suppressed [ 21.649483] random: sshd: uninitialized urandom read (32 bytes read) net.ipv6.conf.syz_tun.accept_dad = 0 net.ipv6.conf.syz_tun.router_solicitations = 0 RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported Error: argument "bridge0" is wrong: Device does not exist Error: argument "bridge0" is wrong: Device does not exist Cannot find device "veth0_to_bridge" Cannot find device "veth1_to_bridge" RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported Error: argument "bond0" is wrong: Device does not exist Error: argument "bond0" is wrong: Device does not exist Cannot find device "veth0_to_bond" Cannot find device "veth1_to_bond" RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported Error: argument "team0" is wrong: Device does not exist Error: argument "team0" is wrong: Device does not exist Cannot find device "veth0_to_team" Cannot find device "veth1_to_team" Cannot find device "bridge_slave_0" Cannot find device "bridge_slave_1" RTNETLINK answers: Operation not supported Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "bridge0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "vcan0" Cannot find device "tunl0" Cannot find device "tunl0" Cannot find device "tunl0" Cannot find device "tunl0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gre0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" Cannot find device "gretap0" RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gre0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "ip6gretap0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "erspan0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "bond0" Cannot find device "veth0" Cannot find device "veth0" Cannot find device "veth0" Cannot find device "veth0" Cannot find device "veth1" Cannot find device "veth1" Cannot find device "veth1" Cannot find device "veth1" Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" Cannot find device "team0" Cannot find device "veth0_to_bridge" Cannot find device "veth0_to_bridge" Cannot find device "veth0_to_bridge" Cannot find device "veth0_to_bridge" Cannot find device "veth1_to_bridge" Cannot find device "veth1_to_bridge" Cannot find device "veth1_to_bridge" Cannot find device "veth1_to_bridge" Cannot find device "veth0_to_bond" Cannot find device "veth0_to_bond" Cannot find device "veth0_to_bond" Cannot find device "veth0_to_bond" Cannot find device "veth1_to_bond" Cannot find device "veth1_to_bond" Cannot find device "veth1_to_bond" Cannot find device "veth1_to_bond" Cannot find device "veth0_to_team" Cannot find device "veth0_to_team" Cannot find device "veth0_to_team" Cannot find device "veth0_to_team" Cannot find device "veth1_to_team" Cannot find device "veth1_to_team" Cannot find device "veth1_to_team" Cannot find device "veth1_to_team" executing program [ 23.451197] ================================================================== [ 23.458573] BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x1595/0x1930 [ 23.465908] Read of size 8 at addr ffff8801c690f6d0 by task syz-executor901/2295 [ 23.473414] [ 23.475016] CPU: 0 PID: 2295 Comm: syz-executor901 Not tainted 4.14.67+ #1 [ 23.481998] Call Trace: [ 23.484568] dump_stack+0xb9/0x11b [ 23.488087] print_address_description+0x60/0x22b [ 23.492904] kasan_report.cold.6+0x11b/0x2dd [ 23.497285] ? unwind_next_frame+0x1595/0x1930 [ 23.501840] unwind_next_frame+0x1595/0x1930 [ 23.506229] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 23.511567] ? deref_stack_reg+0xe0/0xe0 [ 23.515603] ? perf_event_output_forward+0x145/0x230 [ 23.520686] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 23.526029] perf_callchain_kernel+0x39c/0x540 [ 23.530592] ? arch_perf_update_userpage+0x330/0x330 [ 23.535750] ? do_group_exit+0x100/0x2e0 [ 23.539794] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 23.545135] get_perf_callchain+0x2eb/0x760 [ 23.549434] ? put_callchain_buffers+0x60/0x60 [ 23.554004] perf_callchain+0x14a/0x190 [ 23.557956] perf_prepare_sample+0x704/0x13c0 [ 23.562427] ? perf_output_sample+0x16a0/0x16a0 [ 23.567070] ? perf_swevent_put_recursion_context+0x1a/0xa0 [ 23.572759] ? perf_tp_event+0x477/0x790 [ 23.576794] perf_event_output_forward+0xeb/0x230 [ 23.581610] ? perf_prepare_sample+0x13c0/0x13c0 [ 23.586344] ? check_preemption_disabled+0x34/0x160 [ 23.591335] __perf_event_overflow+0x116/0x320 [ 23.595889] perf_swevent_overflow+0x166/0x1f0 [ 23.600445] perf_swevent_event+0x112/0x270 [ 23.604740] perf_tp_event+0x5e5/0x790 [ 23.608604] ? perf_swevent_put_recursion_context+0xa0/0xa0 [ 23.614412] ? perf_trace_run_bpf_submit+0x10f/0x170 [ 23.619497] ? perf_trace_lock+0x2f6/0x4c0 [ 23.623815] ? unwind_next_frame+0xea9/0x1930 [ 23.628291] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 23.633204] ? __is_insn_slot_addr+0x112/0x1f0 [ 23.637769] ? lock_downgrade+0x560/0x560 [ 23.641898] ? lock_acquire+0x10f/0x380 [ 23.645955] ? __free_insn_slot+0x490/0x490 [ 23.650261] ? depot_save_stack+0x20a/0x428 [ 23.654566] ? perf_trace_run_bpf_submit+0x10f/0x170 [ 23.659649] ? check_preemption_disabled+0x34/0x160 [ 23.664642] perf_trace_run_bpf_submit+0x10f/0x170 [ 23.669551] perf_trace_lock+0x2f6/0x4c0 [ 23.673590] ? kasan_slab_free+0x119/0x190 [ 23.677798] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 23.682704] ? kfree_skb+0xc8/0x340 [ 23.686304] ? __tun_detach+0x3b9/0xa10 [ 23.690253] ? tun_chr_close+0x40/0x50 [ 23.694116] ? __fput+0x25e/0x6f0 [ 23.697651] ? task_work_run+0x116/0x190 [ 23.701702] ? do_exit+0x8f8/0x2800 [ 23.705308] ? do_group_exit+0x100/0x2e0 [ 23.709344] ? get_signal+0x4e5/0x1470 [ 23.713207] ? exit_to_usermode_loop+0x116/0x150 [ 23.717939] ? do_syscall_64+0x35d/0x4b0 [ 23.721974] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 23.727312] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 23.732221] lock_release+0x4dc/0x720 [ 23.735998] ? debug_check_no_obj_freed+0x2b2/0x77c [ 23.741094] ? lock_downgrade+0x560/0x560 [ 23.745217] ? lock_acquire+0x10f/0x380 [ 23.749186] ? debug_check_no_obj_freed+0x150/0x77c [ 23.754182] _raw_spin_unlock_irqrestore+0x1b/0x70 [ 23.759087] debug_check_no_obj_freed+0x2b2/0x77c [ 23.764023] ? debug_object_activate+0x4e0/0x4e0 [ 23.768750] ? mark_held_locks+0xc2/0x130 [ 23.772882] ? kmem_cache_free+0x10c/0x350 [ 23.777094] ? kfree_skbmem+0x9e/0x100 [ 23.780953] kmem_cache_free+0x218/0x350 [ 23.784989] ? tun_queue_purge+0x108/0x300 [ 23.789195] kfree_skbmem+0x9e/0x100 [ 23.792884] ? tun_queue_purge+0x108/0x300 [ 23.797092] kfree_skb+0xd0/0x340 [ 23.800518] tun_queue_purge+0x108/0x300 [ 23.804566] __tun_detach+0x3b9/0xa10 [ 23.808338] ? __tun_detach+0xa10/0xa10 [ 23.812285] tun_chr_close+0x40/0x50 [ 23.815986] __fput+0x25e/0x6f0 [ 23.819250] task_work_run+0x116/0x190 [ 23.823212] do_exit+0x8f8/0x2800 [ 23.826644] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 23.831545] ? mm_update_next_owner+0x670/0x670 [ 23.836189] ? get_signal+0x547/0x1470 [ 23.840046] ? recalc_sigpending+0x5c/0x90 [ 23.844251] ? lock_downgrade+0x560/0x560 [ 23.848372] ? get_signal+0x1da/0x1470 [ 23.852237] do_group_exit+0x100/0x2e0 [ 23.856100] get_signal+0x4e5/0x1470 [ 23.859785] ? lock_acquire+0x10f/0x380 [ 23.863761] do_signal+0x8f/0x1660 [ 23.867276] ? get_unused_fd_flags+0xc0/0xc0 [ 23.871657] ? wait_for_completion_io+0x10/0x10 [ 23.876298] ? setup_sigcontext+0x810/0x810 [ 23.880595] ? SyS_perf_event_open+0x687/0x27d0 [ 23.885238] ? do_futex+0x17b0/0x17b0 [ 23.889011] ? exit_to_usermode_loop+0xc6/0x150 [ 23.893655] exit_to_usermode_loop+0x116/0x150 [ 23.898208] do_syscall_64+0x35d/0x4b0 [ 23.902081] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 23.907254] RIP: 0033:0x447679 [ 23.910427] RSP: 002b:00007f2ef2c5ecf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 23.918107] RAX: fffffffffffffe00 RBX: 00000000006ddc28 RCX: 0000000000447679 [ 23.925347] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006ddc28 [ 23.932594] RBP: 00000000006ddc20 R08: 0000000000000000 R09: 0000000000000000 [ 23.939835] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc2c [ 23.947075] R13: 00007ffc61b7646f R14: 00007f2ef2c5f9c0 R15: 0000000000000000 [ 23.954316] [ 23.955915] The buggy address belongs to the page: [ 23.960814] page:ffffea00071a43c0 count:0 mapcount:0 mapping: (null) index:0x0 [ 23.968922] flags: 0x4000000000000000() [ 23.972872] raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff [ 23.980722] raw: 0000000000000000 ffffea00071a43e0 0000000000000000 0000000000000000 [ 23.988571] page dumped because: kasan: bad access detected [ 23.994249] [ 23.995849] Memory state around the buggy address: [ 24.000763] ffff8801c690f580: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 [ 24.008092] ffff8801c690f600: f2 f2 f2 f2 f2 f2 00 f2 f2 f2 00 00 00 00 00 00 [ 24.015425] >ffff8801c690f680: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04 f2 f2 f2 [ 24.022770] ^ [ 24.028724] ffff8801c690f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 24.036073] ffff8801c690f780: 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f2 f2 [ 24.043399] ================================================================== [ 24.050741] Disabling lock debugging due to kernel taint [ 24.056163] Kernel panic - not syncing: panic_on_warn set ... [ 24.056163] [ 24.063498] CPU: 0 PID: 2295 Comm: syz-executor901 Tainted: G B 4.14.67+ #1 [ 24.071792] Call Trace: [ 24.074395] dump_stack+0xb9/0x11b [ 24.077918] panic+0x1bf/0x3a4 [ 24.081084] ? add_taint.cold.4+0x16/0x16 [ 24.085208] kasan_end_report+0x43/0x49 [ 24.089158] kasan_report.cold.6+0x77/0x2dd [ 24.093454] ? unwind_next_frame+0x1595/0x1930 [ 24.098079] unwind_next_frame+0x1595/0x1930 [ 24.102470] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.107806] ? deref_stack_reg+0xe0/0xe0 [ 24.111845] ? perf_event_output_forward+0x145/0x230 [ 24.116924] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.122260] perf_callchain_kernel+0x39c/0x540 [ 24.126830] ? arch_perf_update_userpage+0x330/0x330 [ 24.131926] ? do_group_exit+0x100/0x2e0 [ 24.135959] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.141297] get_perf_callchain+0x2eb/0x760 [ 24.145593] ? put_callchain_buffers+0x60/0x60 [ 24.150150] perf_callchain+0x14a/0x190 [ 24.154099] perf_prepare_sample+0x704/0x13c0 [ 24.158588] ? perf_output_sample+0x16a0/0x16a0 [ 24.163234] ? perf_swevent_put_recursion_context+0x1a/0xa0 [ 24.168921] ? perf_tp_event+0x477/0x790 [ 24.172956] perf_event_output_forward+0xeb/0x230 [ 24.177774] ? perf_prepare_sample+0x13c0/0x13c0 [ 24.182505] ? check_preemption_disabled+0x34/0x160 [ 24.187491] __perf_event_overflow+0x116/0x320 [ 24.192051] perf_swevent_overflow+0x166/0x1f0 [ 24.196605] perf_swevent_event+0x112/0x270 [ 24.200895] perf_tp_event+0x5e5/0x790 [ 24.204755] ? perf_swevent_put_recursion_context+0xa0/0xa0 [ 24.210442] ? perf_trace_run_bpf_submit+0x10f/0x170 [ 24.215634] ? perf_trace_lock+0x2f6/0x4c0 [ 24.219855] ? unwind_next_frame+0xea9/0x1930 [ 24.224335] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 24.229236] ? __is_insn_slot_addr+0x112/0x1f0 [ 24.233790] ? lock_downgrade+0x560/0x560 [ 24.237908] ? lock_acquire+0x10f/0x380 [ 24.241870] ? __free_insn_slot+0x490/0x490 [ 24.246163] ? depot_save_stack+0x20a/0x428 [ 24.250457] ? perf_trace_run_bpf_submit+0x10f/0x170 [ 24.255534] ? check_preemption_disabled+0x34/0x160 [ 24.260521] perf_trace_run_bpf_submit+0x10f/0x170 [ 24.265422] perf_trace_lock+0x2f6/0x4c0 [ 24.269460] ? kasan_slab_free+0x119/0x190 [ 24.273670] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 24.278569] ? kfree_skb+0xc8/0x340 [ 24.282166] ? __tun_detach+0x3b9/0xa10 [ 24.286119] ? tun_chr_close+0x40/0x50 [ 24.289979] ? __fput+0x25e/0x6f0 [ 24.293404] ? task_work_run+0x116/0x190 [ 24.297437] ? do_exit+0x8f8/0x2800 [ 24.301035] ? do_group_exit+0x100/0x2e0 [ 24.305070] ? get_signal+0x4e5/0x1470 [ 24.308944] ? exit_to_usermode_loop+0x116/0x150 [ 24.313670] ? do_syscall_64+0x35d/0x4b0 [ 24.317732] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.323083] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 24.327983] lock_release+0x4dc/0x720 [ 24.331764] ? debug_check_no_obj_freed+0x2b2/0x77c [ 24.336764] ? lock_downgrade+0x560/0x560 [ 24.340880] ? lock_acquire+0x10f/0x380 [ 24.344828] ? debug_check_no_obj_freed+0x150/0x77c [ 24.349816] _raw_spin_unlock_irqrestore+0x1b/0x70 [ 24.354718] debug_check_no_obj_freed+0x2b2/0x77c [ 24.359540] ? debug_object_activate+0x4e0/0x4e0 [ 24.364272] ? mark_held_locks+0xc2/0x130 [ 24.368393] ? kmem_cache_free+0x10c/0x350 [ 24.372604] ? kfree_skbmem+0x9e/0x100 [ 24.376468] kmem_cache_free+0x218/0x350 [ 24.380533] ? tun_queue_purge+0x108/0x300 [ 24.384745] kfree_skbmem+0x9e/0x100 [ 24.388437] ? tun_queue_purge+0x108/0x300 [ 24.392650] kfree_skb+0xd0/0x340 [ 24.396077] tun_queue_purge+0x108/0x300 [ 24.400110] __tun_detach+0x3b9/0xa10 [ 24.403987] ? __tun_detach+0xa10/0xa10 [ 24.407943] tun_chr_close+0x40/0x50 [ 24.411637] __fput+0x25e/0x6f0 [ 24.414895] task_work_run+0x116/0x190 [ 24.418760] do_exit+0x8f8/0x2800 [ 24.422189] ? perf_trace_lock_acquire+0x4d0/0x4d0 [ 24.427107] ? mm_update_next_owner+0x670/0x670 [ 24.431752] ? get_signal+0x547/0x1470 [ 24.435610] ? recalc_sigpending+0x5c/0x90 [ 24.439815] ? lock_downgrade+0x560/0x560 [ 24.443931] ? get_signal+0x1da/0x1470 [ 24.447793] do_group_exit+0x100/0x2e0 [ 24.451655] get_signal+0x4e5/0x1470 [ 24.455343] ? lock_acquire+0x10f/0x380 [ 24.459288] do_signal+0x8f/0x1660 [ 24.462807] ? get_unused_fd_flags+0xc0/0xc0 [ 24.467186] ? wait_for_completion_io+0x10/0x10 [ 24.471828] ? setup_sigcontext+0x810/0x810 [ 24.476123] ? SyS_perf_event_open+0x687/0x27d0 [ 24.480768] ? do_futex+0x17b0/0x17b0 [ 24.484541] ? exit_to_usermode_loop+0xc6/0x150 [ 24.489181] exit_to_usermode_loop+0x116/0x150 [ 24.493879] do_syscall_64+0x35d/0x4b0 [ 24.497746] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.502905] RIP: 0033:0x447679 [ 24.506065] RSP: 002b:00007f2ef2c5ecf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 24.513747] RAX: fffffffffffffe00 RBX: 00000000006ddc28 RCX: 0000000000447679 [ 24.520990] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006ddc28 [ 24.528237] RBP: 00000000006ddc20 R08: 0000000000000000 R09: 0000000000000000 [ 24.535482] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc2c [ 24.542740] R13: 00007ffc61b7646f R14: 00007f2ef2c5f9c0 R15: 0000000000000000 [ 24.550323] Dumping ftrace buffer: [ 24.553843] (ftrace buffer empty) [ 24.557530] Kernel Offset: 0xb200000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 24.568429] Rebooting in 86400 seconds..