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 Warning: Permanently added '10.128.10.16' (ECDSA) to the list of known hosts. net.ipv6.conf.syz_tun.accept_dad = 0 net.ipv6.conf.syz_tun.router_solicitations = 0 syzkaller login: [ 30.676227] IPVS: ftp: loaded support on port[0] = 21 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 30.922863] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported [ 31.024896] ip (4602) used greatest stack depth: 16584 bytes left RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument [ 31.275801] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 31.281923] 8021q: adding VLAN 0 to HW filter on device bond0 [ 31.320606] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 31.360215] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 31.397895] IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready [ 31.404029] 8021q: adding VLAN 0 to HW filter on device team0 [ 31.431693] bond0: Enslaving bond_slave as an active interface with an up link [ 31.439981] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready executing program [ 31.455860] team0: Port device team_slave added [ 31.461186] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 31.498104] ================================================================== [ 31.505533] BUG: KASAN: use-after-free in skb_release_data+0x19b/0x860 [ 31.512177] Write of size 4 at addr ffff8801c5c9b620 by task syzkaller067583/4525 [ 31.519777] [ 31.521391] CPU: 0 PID: 4525 Comm: syzkaller067583 Not tainted 4.16.0+ #17 [ 31.528376] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.537712] Call Trace: [ 31.540289] dump_stack+0x1b9/0x294 [ 31.543903] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.549075] ? printk+0x9e/0xba [ 31.552334] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 31.557072] ? kasan_check_write+0x14/0x20 [ 31.561294] print_address_description+0x6c/0x20b [ 31.566118] ? skb_release_data+0x19b/0x860 [ 31.570418] kasan_report.cold.7+0xac/0x2f5 [ 31.574718] check_memory_region+0x13e/0x1b0 [ 31.579111] kasan_check_write+0x14/0x20 [ 31.583147] skb_release_data+0x19b/0x860 [ 31.587283] ? skb_tx_error+0x2f0/0x2f0 [ 31.591240] ? kasan_check_read+0x11/0x20 [ 31.595364] ? rcu_is_watching+0x85/0x140 [ 31.599488] ? kasan_check_write+0x14/0x20 [ 31.603702] ? sock_rmem_free+0x6f/0x90 [ 31.607654] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.613167] skb_release_all+0x4a/0x60 [ 31.617033] kfree_skb+0x195/0x560 [ 31.620550] ? skb_queue_purge+0x19/0x40 [ 31.624588] ? __kfree_skb+0x20/0x20 [ 31.628280] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.632842] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 31.637932] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.642925] ? trace_hardirqs_on+0xd/0x10 [ 31.647053] ? skb_dequeue+0x12f/0x180 [ 31.650917] skb_queue_purge+0x19/0x40 [ 31.654790] packet_sock_destruct+0x93/0x290 [ 31.659177] ? packet_mm_close+0xc0/0xc0 [ 31.663213] ? graph_lock+0x170/0x170 [ 31.666990] ? __free_object+0x16e/0x330 [ 31.671036] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 31.676294] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.680853] ? packet_mm_close+0xc0/0xc0 [ 31.684889] __sk_destruct+0xff/0xa40 [ 31.688676] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 31.693582] ? graph_lock+0x170/0x170 [ 31.697358] ? lock_downgrade+0x8e0/0x8e0 [ 31.701483] ? __lock_is_held+0xb5/0x140 [ 31.705529] ? kasan_check_read+0x11/0x20 [ 31.709652] ? do_raw_spin_unlock+0x9e/0x2e0 [ 31.714039] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 31.718606] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 31.723691] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.729208] ? refcount_sub_and_test+0x212/0x330 [ 31.734083] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 31.738816] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 31.743568] ? pcpu_free_area+0xa90/0xa90 [ 31.747696] sk_destruct+0x78/0x90 [ 31.751215] __sk_free+0x22e/0x340 [ 31.754739] sk_free+0x42/0x50 [ 31.757910] packet_release+0xa18/0xd50 [ 31.761870] ? lock_downgrade+0x8e0/0x8e0 [ 31.765998] ? packet_lookup_frame+0x270/0x270 [ 31.770557] ? cpumask_weight.constprop.5+0x44/0x44 [ 31.775550] ? do_raw_spin_lock+0xc1/0x200 [ 31.779767] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.785295] ? locks_remove_file+0x3f7/0x5a0 [ 31.789690] ? fcntl_setlk+0x1020/0x1020 [ 31.793728] ? fsnotify+0x415/0x1100 [ 31.797424] ? fsnotify_first_mark+0x330/0x330 [ 31.801988] sock_release+0x96/0x1b0 [ 31.805689] ? sock_alloc_file+0x4e0/0x4e0 [ 31.809908] sock_close+0x16/0x20 [ 31.813344] __fput+0x34d/0x890 [ 31.816604] ? fput+0x1a0/0x1a0 [ 31.819867] ? check_same_owner+0x320/0x320 [ 31.824173] ____fput+0x15/0x20 [ 31.827433] task_work_run+0x1e4/0x290 [ 31.831299] ? task_work_cancel+0x240/0x240 [ 31.835607] ? switch_task_namespaces+0xbd/0xd0 [ 31.840272] do_exit+0x1aee/0x2730 [ 31.843791] ? find_held_lock+0x36/0x1c0 [ 31.847831] ? mm_update_next_owner+0x980/0x980 [ 31.852483] ? kasan_check_read+0x11/0x20 [ 31.856608] ? rcu_is_watching+0x85/0x140 [ 31.860738] ? tun_get+0x22b/0x360 [ 31.864258] ? tun_chr_close+0x60/0x60 [ 31.868128] ? tun_chr_write_iter+0x110/0x154 [ 31.872601] ? fsnotify+0x415/0x1100 [ 31.876300] ? kasan_check_read+0x11/0x20 [ 31.880443] ? rcu_is_watching+0x85/0x140 [ 31.884574] ? rcu_pm_notify+0xc0/0xc0 [ 31.888445] ? vfs_writev+0x255/0x330 [ 31.892221] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.897211] ? kfree+0x1e9/0x260 [ 31.900554] ? vfs_writev+0xfc/0x330 [ 31.904257] ? vfs_iter_write+0xb0/0xb0 [ 31.908215] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.913731] ? sockfd_lookup_light+0xc5/0x160 [ 31.918212] ? __fdget_pos+0xd6/0x1e0 [ 31.921997] ? __fdget_raw+0x20/0x20 [ 31.925695] do_group_exit+0x16f/0x430 [ 31.929567] ? SyS_exit+0x30/0x30 [ 31.932999] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 31.937818] ? do_syscall_64+0xb7/0x9d0 [ 31.941777] ? do_group_exit+0x430/0x430 [ 31.945823] SyS_exit_group+0x1d/0x20 [ 31.949600] do_syscall_64+0x29e/0x9d0 [ 31.953467] ? vmalloc_sync_all+0x30/0x30 [ 31.957595] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.962330] ? syscall_return_slowpath+0x5c0/0x5c0 [ 31.967237] ? syscall_return_slowpath+0x30f/0x5c0 [ 31.972147] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 31.977488] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.982311] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.987478] RIP: 0033:0x441749 [ 31.990648] RSP: 002b:00007ffc8817be18 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 [ 31.998342] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441749 [ 32.005590] RDX: 0000000000441680 RSI: 0000000000000003 RDI: 0000000000000001 [ 32.012844] RBP: 00000000004a3369 R08: 0000000000000311 R09: 00000000006cd018 [ 32.020097] R10: 0000000000000003 R11: 0000000000000202 R12: 00007ffc8817bf08 [ 32.027343] R13: 00000000004024d0 R14: 0000000000000000 R15: 0000000000000000 [ 32.034594] [ 32.036196] Allocated by task 4525: [ 32.039802] save_stack+0x43/0xd0 [ 32.043232] kasan_kmalloc+0xc4/0xe0 [ 32.046928] __kmalloc_node_track_caller+0x47/0x70 [ 32.051833] __kmalloc_reserve.isra.38+0x3a/0xe0 [ 32.056571] __alloc_skb+0x14d/0x780 [ 32.060261] alloc_skb_with_frags+0x137/0x760 [ 32.064730] sock_alloc_send_pskb+0x87a/0xae0 [ 32.069200] packet_sendmsg+0x1bd1/0x6100 [ 32.073326] sock_sendmsg+0xd5/0x120 [ 32.077014] ___sys_sendmsg+0x805/0x940 [ 32.080962] __sys_sendmsg+0x115/0x270 [ 32.084826] SyS_sendmsg+0x29/0x30 [ 32.088343] do_syscall_64+0x29e/0x9d0 [ 32.092206] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.097368] [ 32.098970] Freed by task 4525: [ 32.102224] save_stack+0x43/0xd0 [ 32.105653] __kasan_slab_free+0x11a/0x170 [ 32.109865] kasan_slab_free+0xe/0x10 [ 32.113642] kfree+0xd9/0x260 [ 32.116732] skb_free_head+0x99/0xc0 [ 32.120422] skb_release_data+0x690/0x860 [ 32.124549] skb_release_all+0x4a/0x60 [ 32.128412] kfree_skb+0x195/0x560 [ 32.131931] ip6_tnl_start_xmit+0xa44/0x2290 [ 32.136315] dev_hard_start_xmit+0x264/0xc10 [ 32.140699] __dev_queue_xmit+0x2724/0x34c0 [ 32.144996] dev_queue_xmit+0x17/0x20 [ 32.148771] packet_sendmsg+0x411d/0x6100 [ 32.152896] sock_sendmsg+0xd5/0x120 [ 32.156587] ___sys_sendmsg+0x805/0x940 [ 32.160537] __sys_sendmsg+0x115/0x270 [ 32.164398] SyS_sendmsg+0x29/0x30 [ 32.167923] do_syscall_64+0x29e/0x9d0 [ 32.171792] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.176954] [ 32.178559] The buggy address belongs to the object at ffff8801c5c9b540 [ 32.178559] which belongs to the cache kmalloc-512 of size 512 [ 32.191193] The buggy address is located 224 bytes inside of [ 32.191193] 512-byte region [ffff8801c5c9b540, ffff8801c5c9b740) [ 32.203040] The buggy address belongs to the page: [ 32.207947] page:ffffea00071726c0 count:1 mapcount:0 mapping:ffff8801c5c9b040 index:0x0 [ 32.216069] flags: 0x2fffc0000000100(slab) [ 32.220291] raw: 02fffc0000000100 ffff8801c5c9b040 0000000000000000 0000000100000006 [ 32.228152] raw: ffffea0007172660 ffffea0007172760 ffff8801dac00940 0000000000000000 [ 32.236005] page dumped because: kasan: bad access detected [ 32.241687] [ 32.243290] Memory state around the buggy address: [ 32.248202] ffff8801c5c9b500: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 32.255536] ffff8801c5c9b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.262871] >ffff8801c5c9b600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.270206] ^ [ 32.274591] ffff8801c5c9b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.281925] ffff8801c5c9b700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 32.289258] ================================================================== [ 32.296597] Disabling lock debugging due to kernel taint [ 32.302363] Kernel panic - not syncing: panic_on_warn set ... [ 32.302363] [ 32.309718] CPU: 0 PID: 4525 Comm: syzkaller067583 Tainted: G B 4.16.0+ #17 [ 32.318010] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.327344] Call Trace: [ 32.329917] dump_stack+0x1b9/0x294 [ 32.333524] ? dump_stack_print_info.cold.2+0x52/0x52 [ 32.338691] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.343434] ? skb_release_data+0xd0/0x860 [ 32.347646] panic+0x22f/0x4de [ 32.350814] ? add_taint.cold.5+0x16/0x16 [ 32.354941] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.359326] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.363709] ? skb_release_data+0x19b/0x860 [ 32.368009] kasan_end_report+0x47/0x4f [ 32.371958] kasan_report.cold.7+0xc9/0x2f5 [ 32.376260] check_memory_region+0x13e/0x1b0 [ 32.380642] kasan_check_write+0x14/0x20 [ 32.384676] skb_release_data+0x19b/0x860 [ 32.388802] ? skb_tx_error+0x2f0/0x2f0 [ 32.392751] ? kasan_check_read+0x11/0x20 [ 32.396877] ? rcu_is_watching+0x85/0x140 [ 32.401002] ? kasan_check_write+0x14/0x20 [ 32.405214] ? sock_rmem_free+0x6f/0x90 [ 32.409166] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.414689] skb_release_all+0x4a/0x60 [ 32.418556] kfree_skb+0x195/0x560 [ 32.422080] ? skb_queue_purge+0x19/0x40 [ 32.426122] ? __kfree_skb+0x20/0x20 [ 32.429813] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.434374] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.439451] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.444451] ? trace_hardirqs_on+0xd/0x10 [ 32.448582] ? skb_dequeue+0x12f/0x180 [ 32.452443] skb_queue_purge+0x19/0x40 [ 32.456308] packet_sock_destruct+0x93/0x290 [ 32.460696] ? packet_mm_close+0xc0/0xc0 [ 32.464742] ? graph_lock+0x170/0x170 [ 32.468517] ? __free_object+0x16e/0x330 [ 32.472551] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 32.477811] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.482368] ? packet_mm_close+0xc0/0xc0 [ 32.486409] __sk_destruct+0xff/0xa40 [ 32.490185] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 32.495108] ? graph_lock+0x170/0x170 [ 32.498909] ? lock_downgrade+0x8e0/0x8e0 [ 32.503035] ? __lock_is_held+0xb5/0x140 [ 32.507072] ? kasan_check_read+0x11/0x20 [ 32.511208] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.515592] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.520162] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.525245] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.530758] ? refcount_sub_and_test+0x212/0x330 [ 32.535493] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.540236] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.544968] ? pcpu_free_area+0xa90/0xa90 [ 32.549096] sk_destruct+0x78/0x90 [ 32.552614] __sk_free+0x22e/0x340 [ 32.556129] sk_free+0x42/0x50 [ 32.559299] packet_release+0xa18/0xd50 [ 32.563248] ? lock_downgrade+0x8e0/0x8e0 [ 32.567904] ? packet_lookup_frame+0x270/0x270 [ 32.572467] ? cpumask_weight.constprop.5+0x44/0x44 [ 32.577461] ? do_raw_spin_lock+0xc1/0x200 [ 32.581676] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.587190] ? locks_remove_file+0x3f7/0x5a0 [ 32.591571] ? fcntl_setlk+0x1020/0x1020 [ 32.595607] ? fsnotify+0x415/0x1100 [ 32.599299] ? fsnotify_first_mark+0x330/0x330 [ 32.603861] sock_release+0x96/0x1b0 [ 32.607552] ? sock_alloc_file+0x4e0/0x4e0 [ 32.611857] sock_close+0x16/0x20 [ 32.615287] __fput+0x34d/0x890 [ 32.618542] ? fput+0x1a0/0x1a0 [ 32.621801] ? check_same_owner+0x320/0x320 [ 32.626108] ____fput+0x15/0x20 [ 32.629363] task_work_run+0x1e4/0x290 [ 32.633227] ? task_work_cancel+0x240/0x240 [ 32.637529] ? switch_task_namespaces+0xbd/0xd0 [ 32.642176] do_exit+0x1aee/0x2730 [ 32.645690] ? find_held_lock+0x36/0x1c0 [ 32.649728] ? mm_update_next_owner+0x980/0x980 [ 32.654374] ? kasan_check_read+0x11/0x20 [ 32.658498] ? rcu_is_watching+0x85/0x140 [ 32.662635] ? tun_get+0x22b/0x360 [ 32.666152] ? tun_chr_close+0x60/0x60 [ 32.670017] ? tun_chr_write_iter+0x110/0x154 [ 32.674490] ? fsnotify+0x415/0x1100 [ 32.678184] ? kasan_check_read+0x11/0x20 [ 32.682308] ? rcu_is_watching+0x85/0x140 [ 32.686444] ? rcu_pm_notify+0xc0/0xc0 [ 32.690315] ? vfs_writev+0x255/0x330 [ 32.694100] ? rcu_read_lock_sched_held+0x108/0x120 [ 32.699090] ? kfree+0x1e9/0x260 [ 32.702444] ? vfs_writev+0xfc/0x330 [ 32.706144] ? vfs_iter_write+0xb0/0xb0 [ 32.710109] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.715624] ? sockfd_lookup_light+0xc5/0x160 [ 32.720099] ? __fdget_pos+0xd6/0x1e0 [ 32.723882] ? __fdget_raw+0x20/0x20 [ 32.727580] do_group_exit+0x16f/0x430 [ 32.731448] ? SyS_exit+0x30/0x30 [ 32.734898] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 32.739734] ? do_syscall_64+0xb7/0x9d0 [ 32.743703] ? do_group_exit+0x430/0x430 [ 32.747741] SyS_exit_group+0x1d/0x20 [ 32.751530] do_syscall_64+0x29e/0x9d0 [ 32.755416] ? vmalloc_sync_all+0x30/0x30 [ 32.759541] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.764275] ? syscall_return_slowpath+0x5c0/0x5c0 [ 32.769192] ? syscall_return_slowpath+0x30f/0x5c0 [ 32.774108] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 32.779449] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.784276] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.789442] RIP: 0033:0x441749 [ 32.792605] RSP: 002b:00007ffc8817be18 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 [ 32.800297] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441749 [ 32.807544] RDX: 0000000000441680 RSI: 0000000000000003 RDI: 0000000000000001 [ 32.814792] RBP: 00000000004a3369 R08: 0000000000000311 R09: 00000000006cd018 [ 32.822055] R10: 0000000000000003 R11: 0000000000000202 R12: 00007ffc8817bf08 [ 32.829303] R13: 00000000004024d0 R14: 0000000000000000 R15: 0000000000000000 [ 32.837133] Dumping ftrace buffer: [ 32.840654] (ftrace buffer empty) [ 32.844350] Kernel Offset: disabled [ 32.847955] Rebooting in 86400 seconds..