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: [ 22.071679] sshd (4506) used greatest stack depth: 16216 bytes left Warning: Permanently added '10.128.0.2' (ECDSA) to the list of known hosts. net.ipv6.conf.syz_tun.accept_dad = 0 [ 30.877419] 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 [ 31.147305] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument [ 31.545042] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 31.551152] 8021q: adding VLAN 0 to HW filter on device bond0 [ 31.592754] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 31.635462] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 31.678104] IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready [ 31.684206] 8021q: adding VLAN 0 to HW filter on device team0 [ 31.713137] bond0: Enslaving bond_slave as an active interface with an up link executing program [ 31.722256] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready [ 31.736357] team0: Port device team_slave added [ 31.741712] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 31.780150] ================================================================== [ 31.787620] BUG: KASAN: use-after-free in skb_release_data+0x19b/0x860 [ 31.794277] Write of size 4 at addr ffff8801d46bd160 by task syzkaller175730/4525 [ 31.801872] [ 31.803483] CPU: 0 PID: 4525 Comm: syzkaller175730 Not tainted 4.16.0+ #1 [ 31.810383] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.819715] Call Trace: [ 31.822296] dump_stack+0x1b9/0x294 [ 31.825903] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.831073] ? printk+0x9e/0xba [ 31.834328] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 31.839062] ? kasan_check_write+0x14/0x20 [ 31.843277] print_address_description+0x6c/0x20b [ 31.848100] ? skb_release_data+0x19b/0x860 [ 31.852403] kasan_report.cold.7+0xac/0x2f5 [ 31.856716] check_memory_region+0x13e/0x1b0 [ 31.861104] kasan_check_write+0x14/0x20 [ 31.865142] skb_release_data+0x19b/0x860 [ 31.869276] ? skb_tx_error+0x2f0/0x2f0 [ 31.873242] ? kasan_check_read+0x11/0x20 [ 31.877366] ? rcu_is_watching+0x85/0x140 [ 31.881491] ? kasan_check_write+0x14/0x20 [ 31.885704] ? sock_rmem_free+0x6f/0x90 [ 31.889658] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.895174] skb_release_all+0x4a/0x60 [ 31.899044] kfree_skb+0x195/0x560 [ 31.902564] ? skb_queue_purge+0x19/0x40 [ 31.906600] ? __kfree_skb+0x20/0x20 [ 31.910292] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.914852] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 31.919935] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.924947] ? trace_hardirqs_on+0xd/0x10 [ 31.929101] ? skb_dequeue+0x12f/0x180 [ 31.932973] skb_queue_purge+0x19/0x40 [ 31.936853] packet_sock_destruct+0x93/0x290 [ 31.941247] ? packet_mm_close+0xc0/0xc0 [ 31.945291] ? graph_lock+0x170/0x170 [ 31.949071] ? __free_object+0x16e/0x330 [ 31.953109] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 31.958365] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.962924] ? packet_mm_close+0xc0/0xc0 [ 31.966962] __sk_destruct+0xff/0xa40 [ 31.970742] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 31.975657] ? graph_lock+0x170/0x170 [ 31.979437] ? lock_downgrade+0x8e0/0x8e0 [ 31.983728] ? __lock_is_held+0xb5/0x140 [ 31.987768] ? kasan_check_read+0x11/0x20 [ 31.991895] ? do_raw_spin_unlock+0x9e/0x2e0 [ 31.996282] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.000844] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.005928] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.011445] ? refcount_sub_and_test+0x212/0x330 [ 32.016713] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.021450] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.026184] ? pcpu_free_area+0xa90/0xa90 [ 32.030333] sk_destruct+0x78/0x90 [ 32.033849] __sk_free+0x22e/0x340 [ 32.037365] sk_free+0x42/0x50 [ 32.040540] packet_release+0xa18/0xd50 [ 32.044490] ? lock_downgrade+0x8e0/0x8e0 [ 32.048619] ? packet_lookup_frame+0x270/0x270 [ 32.053181] ? cpumask_weight.constprop.5+0x44/0x44 [ 32.058178] ? do_raw_spin_lock+0xc1/0x200 [ 32.062392] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.067907] ? locks_remove_file+0x3f7/0x5a0 [ 32.072293] ? fcntl_setlk+0x1020/0x1020 [ 32.076339] ? fsnotify+0x415/0x1100 [ 32.080045] ? fsnotify_first_mark+0x330/0x330 [ 32.084612] sock_release+0x96/0x1b0 [ 32.088307] ? sock_alloc_file+0x4e0/0x4e0 [ 32.092517] sock_close+0x16/0x20 [ 32.095944] __fput+0x34d/0x890 [ 32.099204] ? fput+0x1a0/0x1a0 [ 32.102469] ? check_same_owner+0x320/0x320 [ 32.106768] ____fput+0x15/0x20 [ 32.110031] task_work_run+0x1e4/0x290 [ 32.113901] ? task_work_cancel+0x240/0x240 [ 32.118201] ? switch_task_namespaces+0xbd/0xd0 [ 32.122852] do_exit+0x1aee/0x2730 [ 32.126371] ? find_held_lock+0x36/0x1c0 [ 32.130412] ? mm_update_next_owner+0x980/0x980 [ 32.135064] ? kasan_check_read+0x11/0x20 [ 32.139190] ? rcu_is_watching+0x85/0x140 [ 32.143315] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 32.148488] ? tun_get+0x22b/0x360 [ 32.152015] ? tun_chr_close+0x60/0x60 [ 32.155894] ? tun_chr_write_iter+0x110/0x154 [ 32.160369] ? fsnotify+0x415/0x1100 [ 32.164071] ? kasan_check_read+0x11/0x20 [ 32.168199] ? rcu_is_watching+0x85/0x140 [ 32.172340] ? rcu_pm_notify+0xc0/0xc0 [ 32.176225] ? vfs_writev+0x255/0x330 [ 32.180051] ? rcu_read_lock_sched_held+0x108/0x120 [ 32.185058] ? kfree+0x1e9/0x260 [ 32.188414] ? vfs_writev+0xfc/0x330 [ 32.192637] ? vfs_iter_write+0xb0/0xb0 [ 32.196591] ? lock_downgrade+0x8e0/0x8e0 [ 32.200721] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.206241] ? sockfd_lookup_light+0xc5/0x160 [ 32.210878] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.216444] ? __fdget_pos+0xd6/0x1e0 [ 32.220235] ? __fdget_raw+0x20/0x20 [ 32.223943] do_group_exit+0x16f/0x430 [ 32.227808] ? SyS_exit+0x30/0x30 [ 32.231954] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 32.236776] ? do_syscall_64+0xb7/0x9d0 [ 32.240727] ? do_group_exit+0x430/0x430 [ 32.245187] SyS_exit_group+0x1d/0x20 [ 32.248970] do_syscall_64+0x29e/0x9d0 [ 32.253037] ? vmalloc_sync_all+0x30/0x30 [ 32.257166] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.261901] ? syscall_return_slowpath+0x5c0/0x5c0 [ 32.266808] ? syscall_return_slowpath+0x30f/0x5c0 [ 32.272118] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 32.278549] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.283594] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.288764] RIP: 0033:0x441749 [ 32.292180] RSP: 002b:00007fffdf81b088 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 [ 32.300050] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441749 [ 32.307300] RDX: 0000000000441680 RSI: 0000000000000001 RDI: 0000000000000001 [ 32.314643] RBP: 00000000004a3369 R08: 0000000000000000 R09: 00000000006cd018 [ 32.321889] R10: 0000000000000000 R11: 0000000000000206 R12: 00007fffdf81b178 [ 32.329134] R13: 00000000004024d0 R14: 0000000000000000 R15: 0000000000000000 [ 32.336388] [ 32.337994] Allocated by task 4525: [ 32.341605] save_stack+0x43/0xd0 [ 32.345046] kasan_kmalloc+0xc4/0xe0 [ 32.348742] __kmalloc_node_track_caller+0x47/0x70 [ 32.353652] __kmalloc_reserve.isra.38+0x3a/0xe0 [ 32.358390] __alloc_skb+0x14d/0x780 [ 32.362085] alloc_skb_with_frags+0x137/0x760 [ 32.366559] sock_alloc_send_pskb+0x87a/0xae0 [ 32.371041] packet_sendmsg+0x1bd1/0x6100 [ 32.375169] sock_sendmsg+0xd5/0x120 [ 32.378858] ___sys_sendmsg+0x805/0x940 [ 32.382807] __sys_sendmsg+0x115/0x270 [ 32.386672] SyS_sendmsg+0x29/0x30 [ 32.390190] do_syscall_64+0x29e/0x9d0 [ 32.394056] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.399222] [ 32.400825] Freed by task 4525: [ 32.404081] save_stack+0x43/0xd0 [ 32.407513] __kasan_slab_free+0x11a/0x170 [ 32.411727] kasan_slab_free+0xe/0x10 [ 32.415501] kfree+0xd9/0x260 [ 32.418586] skb_free_head+0x99/0xc0 [ 32.422273] skb_release_data+0x690/0x860 [ 32.426394] skb_release_all+0x4a/0x60 [ 32.430256] kfree_skb+0x195/0x560 [ 32.433775] ip6_tnl_start_xmit+0xa44/0x2290 [ 32.438274] dev_hard_start_xmit+0x264/0xc10 [ 32.442669] __dev_queue_xmit+0x2724/0x34c0 [ 32.446968] dev_queue_xmit+0x17/0x20 [ 32.450747] packet_sendmsg+0x411d/0x6100 [ 32.454871] sock_sendmsg+0xd5/0x120 [ 32.458560] ___sys_sendmsg+0x805/0x940 [ 32.462510] __sys_sendmsg+0x115/0x270 [ 32.466372] SyS_sendmsg+0x29/0x30 [ 32.469891] do_syscall_64+0x29e/0x9d0 [ 32.473756] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.478917] [ 32.480522] The buggy address belongs to the object at ffff8801d46bd080 [ 32.480522] which belongs to the cache kmalloc-512 of size 512 [ 32.493158] The buggy address is located 224 bytes inside of [ 32.493158] 512-byte region [ffff8801d46bd080, ffff8801d46bd280) [ 32.505129] The buggy address belongs to the page: [ 32.510042] page:ffffea000751af40 count:1 mapcount:0 mapping:ffff8801d46bd080 index:0x0 [ 32.518163] flags: 0x2fffc0000000100(slab) [ 32.522723] raw: 02fffc0000000100 ffff8801d46bd080 0000000000000000 0000000100000006 [ 32.530581] raw: ffffea000751af20 ffffea000751afa0 ffff8801dac00940 0000000000000000 [ 32.538434] page dumped because: kasan: bad access detected [ 32.544116] [ 32.545717] Memory state around the buggy address: [ 32.550621] ffff8801d46bd000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 32.557965] ffff8801d46bd080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.565323] >ffff8801d46bd100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.572661] ^ [ 32.579140] ffff8801d46bd180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.586478] ffff8801d46bd200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.593811] ================================================================== [ 32.601145] Disabling lock debugging due to kernel taint [ 32.607285] Kernel panic - not syncing: panic_on_warn set ... [ 32.607285] [ 32.614791] CPU: 0 PID: 4525 Comm: syzkaller175730 Tainted: G B 4.16.0+ #1 [ 32.623097] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.632468] Call Trace: [ 32.635039] dump_stack+0x1b9/0x294 [ 32.638652] ? dump_stack_print_info.cold.2+0x52/0x52 [ 32.643832] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.648569] ? skb_release_data+0xd0/0x860 [ 32.652790] panic+0x22f/0x4de [ 32.655966] ? add_taint.cold.5+0x16/0x16 [ 32.660092] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.664476] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.668861] ? skb_release_data+0x19b/0x860 [ 32.673170] kasan_end_report+0x47/0x4f [ 32.677147] kasan_report.cold.7+0xc9/0x2f5 [ 32.681450] check_memory_region+0x13e/0x1b0 [ 32.685841] kasan_check_write+0x14/0x20 [ 32.689894] skb_release_data+0x19b/0x860 [ 32.694031] ? skb_tx_error+0x2f0/0x2f0 [ 32.697999] ? kasan_check_read+0x11/0x20 [ 32.702143] ? rcu_is_watching+0x85/0x140 [ 32.706269] ? kasan_check_write+0x14/0x20 [ 32.710480] ? sock_rmem_free+0x6f/0x90 [ 32.714437] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.719970] skb_release_all+0x4a/0x60 [ 32.723832] kfree_skb+0x195/0x560 [ 32.727347] ? skb_queue_purge+0x19/0x40 [ 32.731388] ? __kfree_skb+0x20/0x20 [ 32.735082] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.739647] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.744727] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.749731] ? trace_hardirqs_on+0xd/0x10 [ 32.753858] ? skb_dequeue+0x12f/0x180 [ 32.757733] skb_queue_purge+0x19/0x40 [ 32.761603] packet_sock_destruct+0x93/0x290 [ 32.765988] ? packet_mm_close+0xc0/0xc0 [ 32.770030] ? graph_lock+0x170/0x170 [ 32.773811] ? __free_object+0x16e/0x330 [ 32.777852] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 32.783106] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.787675] ? packet_mm_close+0xc0/0xc0 [ 32.791717] __sk_destruct+0xff/0xa40 [ 32.795495] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 32.800400] ? graph_lock+0x170/0x170 [ 32.804178] ? lock_downgrade+0x8e0/0x8e0 [ 32.808300] ? __lock_is_held+0xb5/0x140 [ 32.812336] ? kasan_check_read+0x11/0x20 [ 32.816470] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.820856] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.825416] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.830494] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.836013] ? refcount_sub_and_test+0x212/0x330 [ 32.840753] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.845484] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.850216] ? pcpu_free_area+0xa90/0xa90 [ 32.854341] sk_destruct+0x78/0x90 [ 32.857860] __sk_free+0x22e/0x340 [ 32.861375] sk_free+0x42/0x50 [ 32.864544] packet_release+0xa18/0xd50 [ 32.868497] ? lock_downgrade+0x8e0/0x8e0 [ 32.872622] ? packet_lookup_frame+0x270/0x270 [ 32.877197] ? cpumask_weight.constprop.5+0x44/0x44 [ 32.882190] ? do_raw_spin_lock+0xc1/0x200 [ 32.886402] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.891913] ? locks_remove_file+0x3f7/0x5a0 [ 32.896298] ? fcntl_setlk+0x1020/0x1020 [ 32.900333] ? fsnotify+0x415/0x1100 [ 32.904030] ? fsnotify_first_mark+0x330/0x330 [ 32.908591] sock_release+0x96/0x1b0 [ 32.912282] ? sock_alloc_file+0x4e0/0x4e0 [ 32.916576] sock_close+0x16/0x20 [ 32.920008] __fput+0x34d/0x890 [ 32.923270] ? fput+0x1a0/0x1a0 [ 32.926526] ? check_same_owner+0x320/0x320 [ 32.930824] ____fput+0x15/0x20 [ 32.934079] task_work_run+0x1e4/0x290 [ 32.937945] ? task_work_cancel+0x240/0x240 [ 32.942244] ? switch_task_namespaces+0xbd/0xd0 [ 32.946889] do_exit+0x1aee/0x2730 [ 32.950403] ? find_held_lock+0x36/0x1c0 [ 32.954440] ? mm_update_next_owner+0x980/0x980 [ 32.959087] ? kasan_check_read+0x11/0x20 [ 32.963211] ? rcu_is_watching+0x85/0x140 [ 32.967337] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 32.972505] ? tun_get+0x22b/0x360 [ 32.976029] ? tun_chr_close+0x60/0x60 [ 32.979897] ? tun_chr_write_iter+0x110/0x154 [ 32.984367] ? fsnotify+0x415/0x1100 [ 32.988060] ? kasan_check_read+0x11/0x20 [ 32.992186] ? rcu_is_watching+0x85/0x140 [ 32.996321] ? rcu_pm_notify+0xc0/0xc0 [ 33.000193] ? vfs_writev+0x255/0x330 [ 33.003976] ? rcu_read_lock_sched_held+0x108/0x120 [ 33.008984] ? kfree+0x1e9/0x260 [ 33.012330] ? vfs_writev+0xfc/0x330 [ 33.016252] ? vfs_iter_write+0xb0/0xb0 [ 33.020203] ? lock_downgrade+0x8e0/0x8e0 [ 33.024329] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 33.029848] ? sockfd_lookup_light+0xc5/0x160 [ 33.034323] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 33.039838] ? __fdget_pos+0xd6/0x1e0 [ 33.043614] ? __fdget_raw+0x20/0x20 [ 33.047312] do_group_exit+0x16f/0x430 [ 33.051176] ? SyS_exit+0x30/0x30 [ 33.054609] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 33.059431] ? do_syscall_64+0xb7/0x9d0 [ 33.063384] ? do_group_exit+0x430/0x430 [ 33.067432] SyS_exit_group+0x1d/0x20 [ 33.071214] do_syscall_64+0x29e/0x9d0 [ 33.075080] ? vmalloc_sync_all+0x30/0x30 [ 33.079207] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 33.083941] ? syscall_return_slowpath+0x5c0/0x5c0 [ 33.088847] ? syscall_return_slowpath+0x30f/0x5c0 [ 33.093781] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 33.099131] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.103968] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.109144] RIP: 0033:0x441749 [ 33.112317] RSP: 002b:00007fffdf81b088 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7 [ 33.120024] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441749 [ 33.127272] RDX: 0000000000441680 RSI: 0000000000000001 RDI: 0000000000000001 [ 33.134519] RBP: 00000000004a3369 R08: 0000000000000000 R09: 00000000006cd018 [ 33.141774] R10: 0000000000000000 R11: 0000000000000206 R12: 00007fffdf81b178 [ 33.149026] R13: 00000000004024d0 R14: 0000000000000000 R15: 0000000000000000 [ 33.156950] Dumping ftrace buffer: [ 33.160476] (ftrace buffer empty) [ 33.164166] Kernel Offset: disabled [ 33.167769] Rebooting in 86400 seconds..