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 syzkaller login: [ 21.747696] sshd (4452) used greatest stack depth: 16776 bytes left Warning: Permanently added '10.128.0.25' (ECDSA) to the list of known hosts. net.ipv6.conf.syz_tun.accept_dad = 0 net.ipv6.conf.syz_tun.router_solicitations = 0 [ 40.049671] IPVS: ftp: loaded support on port[0] = 21 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported [ 40.297333] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument [ 40.652738] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 40.658846] 8021q: adding VLAN 0 to HW filter on device bond0 [ 40.697903] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 40.735801] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 40.774706] IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready [ 40.780820] 8021q: adding VLAN 0 to HW filter on device team0 [ 40.806615] bond0: Enslaving bond_slave as an active interface with an up link [ 40.814939] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready executing program [ 40.831123] team0: Port device team_slave added [ 40.836450] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 40.878149] ================================================================== [ 40.885601] BUG: KASAN: use-after-free in skb_release_data+0x19b/0x860 [ 40.892251] Write of size 4 at addr ffff8801d46785e0 by task syzkaller784893/4472 [ 40.899848] [ 40.901461] CPU: 0 PID: 4472 Comm: syzkaller784893 Not tainted 4.16.0+ #17 [ 40.908447] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.917783] Call Trace: [ 40.920355] dump_stack+0x1b9/0x294 [ 40.923964] ? dump_stack_print_info.cold.2+0x52/0x52 [ 40.929134] ? printk+0x9e/0xba [ 40.932391] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 40.937127] ? kasan_check_write+0x14/0x20 [ 40.941345] print_address_description+0x6c/0x20b [ 40.946168] ? skb_release_data+0x19b/0x860 [ 40.950476] kasan_report.cold.7+0xac/0x2f5 [ 40.954779] check_memory_region+0x13e/0x1b0 [ 40.959165] kasan_check_write+0x14/0x20 [ 40.963213] skb_release_data+0x19b/0x860 [ 40.967342] ? skb_tx_error+0x2f0/0x2f0 [ 40.971295] ? kasan_check_read+0x11/0x20 [ 40.975431] ? rcu_is_watching+0x85/0x140 [ 40.979559] ? kasan_check_write+0x14/0x20 [ 40.983779] ? sock_rmem_free+0x6f/0x90 [ 40.987736] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 40.993255] skb_release_all+0x4a/0x60 [ 40.997123] kfree_skb+0x195/0x560 [ 41.000641] ? skb_queue_purge+0x19/0x40 [ 41.004684] ? __kfree_skb+0x20/0x20 [ 41.008379] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 41.012945] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 41.018060] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.023064] ? trace_hardirqs_on+0xd/0x10 [ 41.027208] ? skb_dequeue+0x12f/0x180 [ 41.031099] skb_queue_purge+0x19/0x40 [ 41.034980] packet_sock_destruct+0x93/0x290 [ 41.039378] ? packet_mm_close+0xc0/0xc0 [ 41.043422] ? graph_lock+0x170/0x170 [ 41.047202] ? __free_object+0x16e/0x330 [ 41.051251] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 41.056509] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 41.061072] ? packet_mm_close+0xc0/0xc0 [ 41.065113] __sk_destruct+0xff/0xa40 [ 41.068894] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 41.073804] ? graph_lock+0x170/0x170 [ 41.077584] ? lock_downgrade+0x8e0/0x8e0 [ 41.081713] ? __lock_is_held+0xb5/0x140 [ 41.085756] ? kasan_check_read+0x11/0x20 [ 41.089887] ? do_raw_spin_unlock+0x9e/0x2e0 [ 41.094274] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 41.098840] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 41.103972] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.109504] ? refcount_sub_and_test+0x212/0x330 [ 41.114241] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 41.118983] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 41.123718] ? pcpu_free_area+0xa90/0xa90 [ 41.127850] sk_destruct+0x78/0x90 [ 41.131369] __sk_free+0x22e/0x340 [ 41.134889] sk_free+0x42/0x50 [ 41.138064] packet_release+0xa18/0xd50 [ 41.142031] ? lock_downgrade+0x8e0/0x8e0 [ 41.146162] ? packet_lookup_frame+0x270/0x270 [ 41.150724] ? cpumask_weight.constprop.5+0x44/0x44 [ 41.155731] ? do_raw_spin_lock+0xc1/0x200 [ 41.159968] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 41.165485] ? locks_remove_file+0x3f7/0x5a0 [ 41.169871] ? fcntl_setlk+0x1020/0x1020 [ 41.173910] ? fsnotify+0x415/0x1100 [ 41.177609] ? fsnotify_first_mark+0x330/0x330 [ 41.182176] sock_release+0x96/0x1b0 [ 41.185870] ? sock_alloc_file+0x4e0/0x4e0 [ 41.190083] sock_close+0x16/0x20 [ 41.193517] __fput+0x34d/0x890 [ 41.196777] ? fput+0x1a0/0x1a0 [ 41.200041] ? check_same_owner+0x320/0x320 [ 41.204344] ____fput+0x15/0x20 [ 41.207614] task_work_run+0x1e4/0x290 [ 41.211493] ? task_work_cancel+0x240/0x240 [ 41.215798] ? switch_task_namespaces+0xbd/0xd0 [ 41.220450] do_exit+0x1aee/0x2730 [ 41.223968] ? find_held_lock+0x36/0x1c0 [ 41.228007] ? mm_update_next_owner+0x980/0x980 [ 41.232659] ? kasan_check_read+0x11/0x20 [ 41.236789] ? rcu_is_watching+0x85/0x140 [ 41.240916] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 41.246089] ? tun_get+0x22b/0x360 [ 41.249610] ? tun_chr_close+0x60/0x60 [ 41.253488] ? tun_chr_write_iter+0x110/0x154 [ 41.257963] ? fsnotify+0x415/0x1100 [ 41.261658] ? kasan_check_read+0x11/0x20 [ 41.265785] ? rcu_is_watching+0x85/0x140 [ 41.269912] ? rcu_pm_notify+0xc0/0xc0 [ 41.273795] ? vfs_writev+0x255/0x330 [ 41.277575] ? rcu_read_lock_sched_held+0x108/0x120 [ 41.282586] ? kfree+0x1e9/0x260 [ 41.285930] ? vfs_writev+0xfc/0x330 [ 41.289624] ? vfs_iter_write+0xb0/0xb0 [ 41.293584] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 41.299101] ? sockfd_lookup_light+0xc5/0x160 [ 41.303592] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.309108] ? __fdget_pos+0xd6/0x1e0 [ 41.312886] ? __fdget_raw+0x20/0x20 [ 41.316603] do_group_exit+0x16f/0x430 [ 41.320472] ? SyS_exit+0x30/0x30 [ 41.323905] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 41.328727] ? do_syscall_64+0xb7/0x9d0 [ 41.332684] ? do_group_exit+0x430/0x430 [ 41.336722] SyS_exit_group+0x1d/0x20 [ 41.340520] do_syscall_64+0x29e/0x9d0 [ 41.344384] ? vmalloc_sync_all+0x30/0x30 [ 41.348512] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 41.353249] ? syscall_return_slowpath+0x5c0/0x5c0 [ 41.358157] ? syscall_return_slowpath+0x30f/0x5c0 [ 41.363068] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 41.368409] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.373232] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 41.378399] RIP: 0033:0x441909 [ 41.381566] RSP: 002b:00007ffce66bda58 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 [ 41.389253] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441909 [ 41.396514] RDX: 0000000000441840 RSI: 0000000000000001 RDI: 0000000000000001 [ 41.403764] RBP: 00000000004a3529 R08: 00000000016986b0 R09: 00000000006cd018 [ 41.411012] R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffce66bdb68 [ 41.418273] R13: 0000000000402690 R14: 0000000000000000 R15: 0000000000000000 [ 41.425525] [ 41.427132] Allocated by task 4472: [ 41.430752] save_stack+0x43/0xd0 [ 41.434191] kasan_kmalloc+0xc4/0xe0 [ 41.437882] __kmalloc_node_track_caller+0x47/0x70 [ 41.442793] __kmalloc_reserve.isra.38+0x3a/0xe0 [ 41.447525] __alloc_skb+0x14d/0x780 [ 41.451214] alloc_skb_with_frags+0x137/0x760 [ 41.455685] sock_alloc_send_pskb+0x87a/0xae0 [ 41.460158] packet_sendmsg+0x1bd1/0x6100 [ 41.464283] sock_sendmsg+0xd5/0x120 [ 41.467975] ___sys_sendmsg+0x805/0x940 [ 41.471928] __sys_sendmsg+0x115/0x270 [ 41.475792] SyS_sendmsg+0x29/0x30 [ 41.479310] do_syscall_64+0x29e/0x9d0 [ 41.483193] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 41.488353] [ 41.489968] Freed by task 4472: [ 41.493235] save_stack+0x43/0xd0 [ 41.496672] __kasan_slab_free+0x11a/0x170 [ 41.500883] kasan_slab_free+0xe/0x10 [ 41.504658] kfree+0xd9/0x260 [ 41.507741] skb_free_head+0x99/0xc0 [ 41.511440] skb_release_data+0x690/0x860 [ 41.515568] skb_release_all+0x4a/0x60 [ 41.519435] kfree_skb+0x195/0x560 [ 41.522957] ip6_tnl_start_xmit+0xa44/0x2290 [ 41.527344] dev_hard_start_xmit+0x264/0xc10 [ 41.531731] __dev_queue_xmit+0x2724/0x34c0 [ 41.536030] dev_queue_xmit+0x17/0x20 [ 41.539819] packet_sendmsg+0x411d/0x6100 [ 41.543946] sock_sendmsg+0xd5/0x120 [ 41.547636] ___sys_sendmsg+0x805/0x940 [ 41.551586] __sys_sendmsg+0x115/0x270 [ 41.555449] SyS_sendmsg+0x29/0x30 [ 41.558970] do_syscall_64+0x29e/0x9d0 [ 41.562850] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 41.568010] [ 41.569617] The buggy address belongs to the object at ffff8801d4678500 [ 41.569617] which belongs to the cache kmalloc-512 of size 512 [ 41.582252] The buggy address is located 224 bytes inside of [ 41.582252] 512-byte region [ffff8801d4678500, ffff8801d4678700) [ 41.594109] The buggy address belongs to the page: [ 41.599016] page:ffffea0007519e00 count:1 mapcount:0 mapping:ffff8801d4678000 index:0x0 [ 41.607135] flags: 0x2fffc0000000100(slab) [ 41.611352] raw: 02fffc0000000100 ffff8801d4678000 0000000000000000 0000000100000006 [ 41.619224] raw: ffffea0007519da0 ffffea0007519ea0 ffff8801dac00940 0000000000000000 [ 41.627077] page dumped because: kasan: bad access detected [ 41.632758] [ 41.634362] Memory state around the buggy address: [ 41.639267] ffff8801d4678480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.646603] ffff8801d4678500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.653939] >ffff8801d4678580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.661283] ^ [ 41.667751] ffff8801d4678600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.675089] ffff8801d4678680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.682422] ================================================================== [ 41.689753] Disabling lock debugging due to kernel taint [ 41.695511] Kernel panic - not syncing: panic_on_warn set ... [ 41.695511] [ 41.702861] CPU: 0 PID: 4472 Comm: syzkaller784893 Tainted: G B 4.16.0+ #17 [ 41.711148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.720492] Call Trace: [ 41.723064] dump_stack+0x1b9/0x294 [ 41.726668] ? dump_stack_print_info.cold.2+0x52/0x52 [ 41.731838] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 41.736574] ? skb_release_data+0xd0/0x860 [ 41.740795] panic+0x22f/0x4de [ 41.743966] ? add_taint.cold.5+0x16/0x16 [ 41.748093] ? do_raw_spin_unlock+0x9e/0x2e0 [ 41.752478] ? do_raw_spin_unlock+0x9e/0x2e0 [ 41.756864] ? skb_release_data+0x19b/0x860 [ 41.761162] kasan_end_report+0x47/0x4f [ 41.765113] kasan_report.cold.7+0xc9/0x2f5 [ 41.769411] check_memory_region+0x13e/0x1b0 [ 41.773796] kasan_check_write+0x14/0x20 [ 41.777831] skb_release_data+0x19b/0x860 [ 41.781957] ? skb_tx_error+0x2f0/0x2f0 [ 41.785994] ? kasan_check_read+0x11/0x20 [ 41.790120] ? rcu_is_watching+0x85/0x140 [ 41.794244] ? kasan_check_write+0x14/0x20 [ 41.798456] ? sock_rmem_free+0x6f/0x90 [ 41.802408] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 41.807923] skb_release_all+0x4a/0x60 [ 41.811786] kfree_skb+0x195/0x560 [ 41.815300] ? skb_queue_purge+0x19/0x40 [ 41.819339] ? __kfree_skb+0x20/0x20 [ 41.823035] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 41.827602] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 41.832680] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.837691] ? trace_hardirqs_on+0xd/0x10 [ 41.841817] ? skb_dequeue+0x12f/0x180 [ 41.845681] skb_queue_purge+0x19/0x40 [ 41.849552] packet_sock_destruct+0x93/0x290 [ 41.853936] ? packet_mm_close+0xc0/0xc0 [ 41.857972] ? graph_lock+0x170/0x170 [ 41.861759] ? __free_object+0x16e/0x330 [ 41.865795] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 41.871047] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 41.875608] ? packet_mm_close+0xc0/0xc0 [ 41.879647] __sk_destruct+0xff/0xa40 [ 41.883423] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 41.888328] ? graph_lock+0x170/0x170 [ 41.892104] ? lock_downgrade+0x8e0/0x8e0 [ 41.896226] ? __lock_is_held+0xb5/0x140 [ 41.900265] ? kasan_check_read+0x11/0x20 [ 41.904388] ? do_raw_spin_unlock+0x9e/0x2e0 [ 41.908783] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 41.913344] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 41.918435] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 41.923950] ? refcount_sub_and_test+0x212/0x330 [ 41.928689] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 41.933421] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 41.938152] ? pcpu_free_area+0xa90/0xa90 [ 41.942277] sk_destruct+0x78/0x90 [ 41.945791] __sk_free+0x22e/0x340 [ 41.949307] sk_free+0x42/0x50 [ 41.952477] packet_release+0xa18/0xd50 [ 41.956426] ? lock_downgrade+0x8e0/0x8e0 [ 41.960552] ? packet_lookup_frame+0x270/0x270 [ 41.965112] ? cpumask_weight.constprop.5+0x44/0x44 [ 41.970104] ? do_raw_spin_lock+0xc1/0x200 [ 41.974315] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 41.979828] ? locks_remove_file+0x3f7/0x5a0 [ 41.984212] ? fcntl_setlk+0x1020/0x1020 [ 41.988264] ? fsnotify+0x415/0x1100 [ 41.991957] ? fsnotify_first_mark+0x330/0x330 [ 41.996514] sock_release+0x96/0x1b0 [ 42.000203] ? sock_alloc_file+0x4e0/0x4e0 [ 42.004434] sock_close+0x16/0x20 [ 42.007864] __fput+0x34d/0x890 [ 42.011121] ? fput+0x1a0/0x1a0 [ 42.014379] ? check_same_owner+0x320/0x320 [ 42.018684] ____fput+0x15/0x20 [ 42.021940] task_work_run+0x1e4/0x290 [ 42.025803] ? task_work_cancel+0x240/0x240 [ 42.030104] ? switch_task_namespaces+0xbd/0xd0 [ 42.034753] do_exit+0x1aee/0x2730 [ 42.038273] ? find_held_lock+0x36/0x1c0 [ 42.042315] ? mm_update_next_owner+0x980/0x980 [ 42.046962] ? kasan_check_read+0x11/0x20 [ 42.051087] ? rcu_is_watching+0x85/0x140 [ 42.055211] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 42.060382] ? tun_get+0x22b/0x360 [ 42.063897] ? tun_chr_close+0x60/0x60 [ 42.067772] ? tun_chr_write_iter+0x110/0x154 [ 42.072243] ? fsnotify+0x415/0x1100 [ 42.075949] ? kasan_check_read+0x11/0x20 [ 42.080072] ? rcu_is_watching+0x85/0x140 [ 42.084206] ? rcu_pm_notify+0xc0/0xc0 [ 42.088195] ? vfs_writev+0x255/0x330 [ 42.091977] ? rcu_read_lock_sched_held+0x108/0x120 [ 42.096974] ? kfree+0x1e9/0x260 [ 42.100317] ? vfs_writev+0xfc/0x330 [ 42.104009] ? vfs_iter_write+0xb0/0xb0 [ 42.107964] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 42.113480] ? sockfd_lookup_light+0xc5/0x160 [ 42.117951] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 42.123465] ? __fdget_pos+0xd6/0x1e0 [ 42.127244] ? __fdget_raw+0x20/0x20 [ 42.130939] do_group_exit+0x16f/0x430 [ 42.134804] ? SyS_exit+0x30/0x30 [ 42.138238] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 42.143055] ? do_syscall_64+0xb7/0x9d0 [ 42.147006] ? do_group_exit+0x430/0x430 [ 42.151042] SyS_exit_group+0x1d/0x20 [ 42.154818] do_syscall_64+0x29e/0x9d0 [ 42.158685] ? vmalloc_sync_all+0x30/0x30 [ 42.162808] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 42.167539] ? syscall_return_slowpath+0x5c0/0x5c0 [ 42.172445] ? syscall_return_slowpath+0x30f/0x5c0 [ 42.177353] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 42.182693] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.187512] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 42.192686] RIP: 0033:0x441909 [ 42.195850] RSP: 002b:00007ffce66bda58 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 [ 42.203537] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441909 [ 42.210783] RDX: 0000000000441840 RSI: 0000000000000001 RDI: 0000000000000001 [ 42.218028] RBP: 00000000004a3529 R08: 00000000016986b0 R09: 00000000006cd018 [ 42.225273] R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffce66bdb68 [ 42.232519] R13: 0000000000402690 R14: 0000000000000000 R15: 0000000000000000 [ 42.240181] Dumping ftrace buffer: [ 42.243708] (ftrace buffer empty) [ 42.247394] Kernel Offset: disabled [ 42.250996] Rebooting in 86400 seconds..