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: [ 22.932455] sshd (4512) used greatest stack depth: 16776 bytes left Warning: Permanently added '10.128.0.19' (ECDSA) to the list of known hosts. net.ipv6.conf.syz_tun.accept_dad = 0 [ 29.466564] IPVS: ftp: loaded support on port[0] = 21 net.ipv6.conf.syz_tun.router_solicitations = 0 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 29.770466] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported [ 29.893392] ip (4607) used greatest stack depth: 16584 bytes left RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument [ 30.197013] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 30.203289] 8021q: adding VLAN 0 to HW filter on device bond0 [ 30.247927] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 30.293738] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 30.339425] IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready [ 30.345544] 8021q: adding VLAN 0 to HW filter on device team0 [ 30.376100] bond0: Enslaving bond_slave as an active interface with an up link executing program [ 30.385898] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 30.400593] team0: Port device team_slave added [ 30.405978] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 30.446159] ================================================================== [ 30.453638] BUG: KASAN: use-after-free in skb_release_data+0x19b/0x860 [ 30.460289] Write of size 4 at addr ffff8801afcf5920 by task syzkaller699218/4530 [ 30.467890] [ 30.469505] CPU: 0 PID: 4530 Comm: syzkaller699218 Not tainted 4.16.0+ #17 [ 30.476499] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.485838] Call Trace: [ 30.488414] dump_stack+0x1b9/0x294 [ 30.492039] ? dump_stack_print_info.cold.2+0x52/0x52 [ 30.497227] ? printk+0x9e/0xba [ 30.500529] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 30.505307] ? kasan_check_write+0x14/0x20 [ 30.509563] print_address_description+0x6c/0x20b [ 30.514404] ? skb_release_data+0x19b/0x860 [ 30.518834] kasan_report.cold.7+0xac/0x2f5 [ 30.523141] check_memory_region+0x13e/0x1b0 [ 30.527536] kasan_check_write+0x14/0x20 [ 30.531577] skb_release_data+0x19b/0x860 [ 30.535726] ? skb_tx_error+0x2f0/0x2f0 [ 30.539682] ? kasan_check_read+0x11/0x20 [ 30.543899] ? rcu_is_watching+0x85/0x140 [ 30.548039] ? kasan_check_write+0x14/0x20 [ 30.552253] ? sock_rmem_free+0x6f/0x90 [ 30.556227] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.561850] skb_release_all+0x4a/0x60 [ 30.565727] kfree_skb+0x195/0x560 [ 30.569247] ? skb_queue_purge+0x19/0x40 [ 30.573295] ? __kfree_skb+0x20/0x20 [ 30.577001] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 30.581573] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 30.586663] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 30.591758] ? trace_hardirqs_on+0xd/0x10 [ 30.595900] ? skb_dequeue+0x12f/0x180 [ 30.599768] skb_queue_purge+0x19/0x40 [ 30.603639] packet_sock_destruct+0x93/0x290 [ 30.608035] ? packet_mm_close+0xc0/0xc0 [ 30.612091] ? graph_lock+0x170/0x170 [ 30.615914] ? __free_object+0x16e/0x330 [ 30.619962] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 30.625251] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 30.629837] ? packet_mm_close+0xc0/0xc0 [ 30.633917] __sk_destruct+0xff/0xa40 [ 30.637712] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 30.642628] ? graph_lock+0x170/0x170 [ 30.646417] ? lock_downgrade+0x8e0/0x8e0 [ 30.650546] ? __lock_is_held+0xb5/0x140 [ 30.654682] ? kasan_check_read+0x11/0x20 [ 30.658837] ? do_raw_spin_unlock+0x9e/0x2e0 [ 30.663234] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 30.667807] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 30.672984] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.678510] ? refcount_sub_and_test+0x212/0x330 [ 30.683263] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 30.688002] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 30.692764] ? pcpu_free_area+0xa90/0xa90 [ 30.696907] sk_destruct+0x78/0x90 [ 30.700430] __sk_free+0x22e/0x340 [ 30.703952] sk_free+0x42/0x50 [ 30.707235] packet_release+0xa18/0xd50 [ 30.712068] ? lock_downgrade+0x8e0/0x8e0 [ 30.716208] ? packet_lookup_frame+0x270/0x270 [ 30.720773] ? cpumask_weight.constprop.5+0x44/0x44 [ 30.725790] ? do_raw_spin_lock+0xc1/0x200 [ 30.730016] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.735546] ? locks_remove_file+0x3f7/0x5a0 [ 30.739944] ? fcntl_setlk+0x1020/0x1020 [ 30.743985] ? fsnotify+0x415/0x1100 [ 30.747683] ? fsnotify_first_mark+0x330/0x330 [ 30.752256] sock_release+0x96/0x1b0 [ 30.755949] ? sock_alloc_file+0x4e0/0x4e0 [ 30.760178] sock_close+0x16/0x20 [ 30.763620] __fput+0x34d/0x890 [ 30.766890] ? fput+0x1a0/0x1a0 [ 30.770164] ? check_same_owner+0x320/0x320 [ 30.774481] ____fput+0x15/0x20 [ 30.777744] task_work_run+0x1e4/0x290 [ 30.781612] ? task_work_cancel+0x240/0x240 [ 30.785919] ? switch_task_namespaces+0xbd/0xd0 [ 30.790580] do_exit+0x1aee/0x2730 [ 30.794110] ? find_held_lock+0x36/0x1c0 [ 30.798157] ? mm_update_next_owner+0x980/0x980 [ 30.802814] ? kasan_check_read+0x11/0x20 [ 30.806944] ? rcu_is_watching+0x85/0x140 [ 30.811077] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 30.816252] ? tun_get+0x22b/0x360 [ 30.819776] ? tun_chr_close+0x60/0x60 [ 30.823645] ? tun_chr_write_iter+0x110/0x154 [ 30.828120] ? fsnotify+0x415/0x1100 [ 30.831826] ? kasan_check_read+0x11/0x20 [ 30.835958] ? rcu_is_watching+0x85/0x140 [ 30.840087] ? rcu_pm_notify+0xc0/0xc0 [ 30.843956] ? vfs_writev+0x255/0x330 [ 30.847739] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.852742] ? kfree+0x1e9/0x260 [ 30.856127] ? vfs_writev+0xfc/0x330 [ 30.859832] ? vfs_iter_write+0xb0/0xb0 [ 30.863794] ? lock_downgrade+0x8e0/0x8e0 [ 30.867926] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.873444] ? sockfd_lookup_light+0xc5/0x160 [ 30.877920] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.883435] ? __fdget_pos+0xd6/0x1e0 [ 30.887214] ? __fdget_raw+0x20/0x20 [ 30.890917] do_group_exit+0x16f/0x430 [ 30.894784] ? SyS_exit+0x30/0x30 [ 30.898219] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 30.903047] ? do_syscall_64+0xb7/0x9d0 [ 30.907006] ? do_group_exit+0x430/0x430 [ 30.911054] SyS_exit_group+0x1d/0x20 [ 30.914836] do_syscall_64+0x29e/0x9d0 [ 30.918708] ? vmalloc_sync_all+0x30/0x30 [ 30.922841] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 30.927579] ? syscall_return_slowpath+0x5c0/0x5c0 [ 30.932579] ? syscall_return_slowpath+0x30f/0x5c0 [ 30.937504] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 30.942852] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.947683] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 30.952855] RIP: 0033:0x441819 [ 30.956027] RSP: 002b:00007ffda554b538 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 [ 30.963715] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441819 [ 30.970968] RDX: 0000000000441750 RSI: 0000000000000001 RDI: 0000000000000001 [ 30.978225] RBP: 00000000004a3429 R08: 0000000000000000 R09: 00000000006cd018 [ 30.985476] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffda554b628 [ 30.992745] R13: 00000000004025a0 R14: 0000000000000000 R15: 0000000000000000 [ 31.000005] [ 31.001618] Allocated by task 4530: [ 31.005232] save_stack+0x43/0xd0 [ 31.008692] kasan_kmalloc+0xc4/0xe0 [ 31.012422] __kmalloc_node_track_caller+0x47/0x70 [ 31.017372] __kmalloc_reserve.isra.38+0x3a/0xe0 [ 31.022111] __alloc_skb+0x14d/0x780 [ 31.025801] alloc_skb_with_frags+0x137/0x760 [ 31.030276] sock_alloc_send_pskb+0x87a/0xae0 [ 31.034839] packet_sendmsg+0x1bd1/0x6100 [ 31.038974] sock_sendmsg+0xd5/0x120 [ 31.042666] ___sys_sendmsg+0x805/0x940 [ 31.046628] __sys_sendmsg+0x115/0x270 [ 31.050490] SyS_sendmsg+0x29/0x30 [ 31.054014] do_syscall_64+0x29e/0x9d0 [ 31.057887] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.063045] [ 31.064647] Freed by task 4530: [ 31.067925] save_stack+0x43/0xd0 [ 31.071352] __kasan_slab_free+0x11a/0x170 [ 31.075559] kasan_slab_free+0xe/0x10 [ 31.079332] kfree+0xd9/0x260 [ 31.082414] skb_free_head+0x99/0xc0 [ 31.086102] skb_release_data+0x690/0x860 [ 31.090225] skb_release_all+0x4a/0x60 [ 31.094088] kfree_skb+0x195/0x560 [ 31.097604] ip6_tnl_start_xmit+0xa44/0x2290 [ 31.101994] dev_hard_start_xmit+0x264/0xc10 [ 31.106383] __dev_queue_xmit+0x2724/0x34c0 [ 31.110683] dev_queue_xmit+0x17/0x20 [ 31.114459] packet_sendmsg+0x411d/0x6100 [ 31.118583] sock_sendmsg+0xd5/0x120 [ 31.122271] ___sys_sendmsg+0x805/0x940 [ 31.126417] __sys_sendmsg+0x115/0x270 [ 31.130281] SyS_sendmsg+0x29/0x30 [ 31.133958] do_syscall_64+0x29e/0x9d0 [ 31.137837] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.143004] [ 31.144620] The buggy address belongs to the object at ffff8801afcf5840 [ 31.144620] which belongs to the cache kmalloc-512 of size 512 [ 31.157450] The buggy address is located 224 bytes inside of [ 31.157450] 512-byte region [ffff8801afcf5840, ffff8801afcf5a40) [ 31.169303] The buggy address belongs to the page: [ 31.174225] page:ffffea0006bf3d40 count:1 mapcount:0 mapping:ffff8801afcf50c0 index:0x0 [ 31.182353] flags: 0x2fffc0000000100(slab) [ 31.186574] raw: 02fffc0000000100 ffff8801afcf50c0 0000000000000000 0000000100000006 [ 31.194529] raw: ffffea0006c164e0 ffffea000766fd60 ffff8801dac00940 0000000000000000 [ 31.202382] page dumped because: kasan: bad access detected [ 31.208151] [ 31.209754] Memory state around the buggy address: [ 31.214856] ffff8801afcf5800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 31.222193] ffff8801afcf5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.229788] >ffff8801afcf5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.237212] ^ [ 31.241616] ffff8801afcf5980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.248958] ffff8801afcf5a00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 31.256303] ================================================================== [ 31.263638] Disabling lock debugging due to kernel taint [ 31.269225] Kernel panic - not syncing: panic_on_warn set ... [ 31.269225] [ 31.276709] CPU: 0 PID: 4530 Comm: syzkaller699218 Tainted: G B 4.16.0+ #17 [ 31.285025] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.294389] Call Trace: [ 31.296985] dump_stack+0x1b9/0x294 [ 31.300598] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.305780] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.310546] ? skb_release_data+0xd0/0x860 [ 31.314781] panic+0x22f/0x4de [ 31.317962] ? add_taint.cold.5+0x16/0x16 [ 31.322143] ? do_raw_spin_unlock+0x9e/0x2e0 [ 31.326538] ? do_raw_spin_unlock+0x9e/0x2e0 [ 31.330933] ? skb_release_data+0x19b/0x860 [ 31.335248] kasan_end_report+0x47/0x4f [ 31.339206] kasan_report.cold.7+0xc9/0x2f5 [ 31.343686] check_memory_region+0x13e/0x1b0 [ 31.348104] kasan_check_write+0x14/0x20 [ 31.352145] skb_release_data+0x19b/0x860 [ 31.356285] ? skb_tx_error+0x2f0/0x2f0 [ 31.360248] ? kasan_check_read+0x11/0x20 [ 31.364393] ? rcu_is_watching+0x85/0x140 [ 31.368545] ? kasan_check_write+0x14/0x20 [ 31.372771] ? sock_rmem_free+0x6f/0x90 [ 31.376737] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.382258] skb_release_all+0x4a/0x60 [ 31.386128] kfree_skb+0x195/0x560 [ 31.389651] ? skb_queue_purge+0x19/0x40 [ 31.393700] ? __kfree_skb+0x20/0x20 [ 31.397395] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.401962] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 31.407056] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.412055] ? trace_hardirqs_on+0xd/0x10 [ 31.416185] ? skb_dequeue+0x12f/0x180 [ 31.420053] skb_queue_purge+0x19/0x40 [ 31.423934] packet_sock_destruct+0x93/0x290 [ 31.428333] ? packet_mm_close+0xc0/0xc0 [ 31.432384] ? graph_lock+0x170/0x170 [ 31.436177] ? __free_object+0x16e/0x330 [ 31.440220] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 31.445490] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.450053] ? packet_mm_close+0xc0/0xc0 [ 31.454097] __sk_destruct+0xff/0xa40 [ 31.457882] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 31.462796] ? graph_lock+0x170/0x170 [ 31.466588] ? lock_downgrade+0x8e0/0x8e0 [ 31.470718] ? __lock_is_held+0xb5/0x140 [ 31.474762] ? kasan_check_read+0x11/0x20 [ 31.478896] ? do_raw_spin_unlock+0x9e/0x2e0 [ 31.483288] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.487856] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 31.492943] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.498465] ? refcount_sub_and_test+0x212/0x330 [ 31.503203] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 31.507952] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 31.512698] ? pcpu_free_area+0xa90/0xa90 [ 31.516833] sk_destruct+0x78/0x90 [ 31.520365] __sk_free+0x22e/0x340 [ 31.523887] sk_free+0x42/0x50 [ 31.527060] packet_release+0xa18/0xd50 [ 31.531021] ? lock_downgrade+0x8e0/0x8e0 [ 31.535159] ? packet_lookup_frame+0x270/0x270 [ 31.539725] ? cpumask_weight.constprop.5+0x44/0x44 [ 31.544743] ? do_raw_spin_lock+0xc1/0x200 [ 31.548973] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.554492] ? locks_remove_file+0x3f7/0x5a0 [ 31.558903] ? fcntl_setlk+0x1020/0x1020 [ 31.562953] ? fsnotify+0x415/0x1100 [ 31.566657] ? fsnotify_first_mark+0x330/0x330 [ 31.571237] sock_release+0x96/0x1b0 [ 31.574947] ? sock_alloc_file+0x4e0/0x4e0 [ 31.579174] sock_close+0x16/0x20 [ 31.582614] __fput+0x34d/0x890 [ 31.585888] ? fput+0x1a0/0x1a0 [ 31.589162] ? check_same_owner+0x320/0x320 [ 31.593476] ____fput+0x15/0x20 [ 31.596755] task_work_run+0x1e4/0x290 [ 31.600637] ? task_work_cancel+0x240/0x240 [ 31.604968] ? switch_task_namespaces+0xbd/0xd0 [ 31.609621] do_exit+0x1aee/0x2730 [ 31.613145] ? find_held_lock+0x36/0x1c0 [ 31.617190] ? mm_update_next_owner+0x980/0x980 [ 31.621845] ? kasan_check_read+0x11/0x20 [ 31.625976] ? rcu_is_watching+0x85/0x140 [ 31.630116] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 31.635294] ? tun_get+0x22b/0x360 [ 31.638837] ? tun_chr_close+0x60/0x60 [ 31.642711] ? tun_chr_write_iter+0x110/0x154 [ 31.647211] ? fsnotify+0x415/0x1100 [ 31.650915] ? kasan_check_read+0x11/0x20 [ 31.655051] ? rcu_is_watching+0x85/0x140 [ 31.659182] ? rcu_pm_notify+0xc0/0xc0 [ 31.663578] ? vfs_writev+0x255/0x330 [ 31.667367] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.672382] ? kfree+0x1e9/0x260 [ 31.675744] ? vfs_writev+0xfc/0x330 [ 31.679449] ? vfs_iter_write+0xb0/0xb0 [ 31.683407] ? lock_downgrade+0x8e0/0x8e0 [ 31.687552] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.693115] ? sockfd_lookup_light+0xc5/0x160 [ 31.697629] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.703168] ? __fdget_pos+0xd6/0x1e0 [ 31.706976] ? __fdget_raw+0x20/0x20 [ 31.710703] do_group_exit+0x16f/0x430 [ 31.714577] ? SyS_exit+0x30/0x30 [ 31.718023] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 31.722856] ? do_syscall_64+0xb7/0x9d0 [ 31.726952] ? do_group_exit+0x430/0x430 [ 31.731023] SyS_exit_group+0x1d/0x20 [ 31.734825] do_syscall_64+0x29e/0x9d0 [ 31.738709] ? vmalloc_sync_all+0x30/0x30 [ 31.742930] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.748039] ? syscall_return_slowpath+0x5c0/0x5c0 [ 31.752976] ? syscall_return_slowpath+0x30f/0x5c0 [ 31.757920] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 31.763289] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.768128] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.773303] RIP: 0033:0x441819 [ 31.776487] RSP: 002b:00007ffda554b538 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 [ 31.784200] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441819 [ 31.791474] RDX: 0000000000441750 RSI: 0000000000000001 RDI: 0000000000000001 [ 31.798726] RBP: 00000000004a3429 R08: 0000000000000000 R09: 00000000006cd018 [ 31.805984] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffda554b628 [ 31.813247] R13: 00000000004025a0 R14: 0000000000000000 R15: 0000000000000000 [ 31.821089] Dumping ftrace buffer: [ 31.824621] (ftrace buffer empty) [ 31.828312] Kernel Offset: disabled [ 31.831921] Rebooting in 86400 seconds..