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 '10.128.10.33' (ECDSA) to the list of known hosts. net.ipv6.conf.syz_tun.accept_dad = 0 syzkaller login: [ 31.639310] IPVS: ftp: loaded support on port[0] = 21 net.ipv6.conf.syz_tun.router_solicitations = 0 [ 31.729897] ip (4441) used greatest stack depth: 16584 bytes left RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 31.895299] 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 [ 32.255873] IPv6: ADDRCONF(NETDEV_UP): bond0: link is not ready [ 32.261980] 8021q: adding VLAN 0 to HW filter on device bond0 [ 32.299205] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 32.338205] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 32.377748] IPv6: ADDRCONF(NETDEV_UP): team0: link is not ready [ 32.383843] 8021q: adding VLAN 0 to HW filter on device team0 [ 32.410537] bond0: Enslaving bond_slave as an active interface with an up link [ 32.419621] IPv6: ADDRCONF(NETDEV_CHANGE): bond0: link becomes ready executing program [ 32.432307] team0: Port device team_slave added [ 32.437527] IPv6: ADDRCONF(NETDEV_CHANGE): team0: link becomes ready [ 32.472102] ================================================================== [ 32.479521] BUG: KASAN: use-after-free in skb_release_data+0x19b/0x860 [ 32.486174] Write of size 4 at addr ffff8801b49bbb20 by task syzkaller487790/4425 [ 32.493773] [ 32.495381] CPU: 0 PID: 4425 Comm: syzkaller487790 Not tainted 4.16.0+ #17 [ 32.502366] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.511697] Call Trace: [ 32.514265] dump_stack+0x1b9/0x294 [ 32.517882] ? dump_stack_print_info.cold.2+0x52/0x52 [ 32.523051] ? printk+0x9e/0xba [ 32.526306] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 32.531044] ? kasan_check_write+0x14/0x20 [ 32.535257] print_address_description+0x6c/0x20b [ 32.540078] ? skb_release_data+0x19b/0x860 [ 32.544376] kasan_report.cold.7+0xac/0x2f5 [ 32.548677] check_memory_region+0x13e/0x1b0 [ 32.553068] kasan_check_write+0x14/0x20 [ 32.557106] skb_release_data+0x19b/0x860 [ 32.561233] ? skb_tx_error+0x2f0/0x2f0 [ 32.565181] ? kasan_check_read+0x11/0x20 [ 32.569318] ? rcu_is_watching+0x85/0x140 [ 32.573442] ? kasan_check_write+0x14/0x20 [ 32.577655] ? sock_rmem_free+0x6f/0x90 [ 32.581608] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.587124] skb_release_all+0x4a/0x60 [ 32.590987] kfree_skb+0x195/0x560 [ 32.594503] ? skb_queue_purge+0x19/0x40 [ 32.598540] ? __kfree_skb+0x20/0x20 [ 32.602232] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.606793] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.611874] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.616867] ? trace_hardirqs_on+0xd/0x10 [ 32.621001] ? skb_dequeue+0x12f/0x180 [ 32.624872] skb_queue_purge+0x19/0x40 [ 32.628738] packet_sock_destruct+0x93/0x290 [ 32.633123] ? packet_mm_close+0xc0/0xc0 [ 32.637159] ? graph_lock+0x170/0x170 [ 32.640935] ? __free_object+0x16e/0x330 [ 32.644972] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 32.650232] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.654796] ? packet_mm_close+0xc0/0xc0 [ 32.658834] __sk_destruct+0xff/0xa40 [ 32.662614] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 32.667523] ? graph_lock+0x170/0x170 [ 32.671300] ? lock_downgrade+0x8e0/0x8e0 [ 32.675424] ? __lock_is_held+0xb5/0x140 [ 32.679464] ? kasan_check_read+0x11/0x20 [ 32.683588] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.687972] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.692533] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.697615] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.703130] ? refcount_sub_and_test+0x212/0x330 [ 32.707871] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.712602] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 32.717333] ? pcpu_free_area+0xa90/0xa90 [ 32.721458] sk_destruct+0x78/0x90 [ 32.724974] __sk_free+0x22e/0x340 [ 32.728491] sk_free+0x42/0x50 [ 32.731662] packet_release+0xa18/0xd50 [ 32.735615] ? lock_downgrade+0x8e0/0x8e0 [ 32.739741] ? packet_lookup_frame+0x270/0x270 [ 32.744303] ? cpumask_weight.constprop.5+0x44/0x44 [ 32.749295] ? do_raw_spin_lock+0xc1/0x200 [ 32.753509] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.759031] ? locks_remove_file+0x3f7/0x5a0 [ 32.763417] ? fcntl_setlk+0x1020/0x1020 [ 32.767455] ? fsnotify+0x415/0x1100 [ 32.771148] ? fsnotify_first_mark+0x330/0x330 [ 32.775711] sock_release+0x96/0x1b0 [ 32.779400] ? sock_alloc_file+0x4e0/0x4e0 [ 32.783609] sock_close+0x16/0x20 [ 32.787041] __fput+0x34d/0x890 [ 32.790298] ? fput+0x1a0/0x1a0 [ 32.793560] ? check_same_owner+0x320/0x320 [ 32.797862] ____fput+0x15/0x20 [ 32.801117] task_work_run+0x1e4/0x290 [ 32.804982] ? task_work_cancel+0x240/0x240 [ 32.809289] ? switch_task_namespaces+0xbd/0xd0 [ 32.814038] do_exit+0x1aee/0x2730 [ 32.817554] ? find_held_lock+0x36/0x1c0 [ 32.821593] ? mm_update_next_owner+0x980/0x980 [ 32.826244] ? kasan_check_read+0x11/0x20 [ 32.830369] ? rcu_is_watching+0x85/0x140 [ 32.834495] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 32.839670] ? tun_get+0x22b/0x360 [ 32.843184] ? tun_chr_close+0x60/0x60 [ 32.847067] ? tun_chr_write_iter+0x110/0x154 [ 32.851542] ? fsnotify+0x415/0x1100 [ 32.855235] ? kasan_check_read+0x11/0x20 [ 32.859359] ? rcu_is_watching+0x85/0x140 [ 32.863482] ? rcu_pm_notify+0xc0/0xc0 [ 32.867349] ? vfs_writev+0x255/0x330 [ 32.871125] ? rcu_read_lock_sched_held+0x108/0x120 [ 32.876125] ? kfree+0x1e9/0x260 [ 32.879468] ? vfs_writev+0xfc/0x330 [ 32.883160] ? vfs_iter_write+0xb0/0xb0 [ 32.887119] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.892634] ? sockfd_lookup_light+0xc5/0x160 [ 32.897107] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.902621] ? __fdget_pos+0xd6/0x1e0 [ 32.906400] ? __fdget_raw+0x20/0x20 [ 32.910093] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.915611] ? __sys_setsockopt+0x24f/0x390 [ 32.919919] do_group_exit+0x16f/0x430 [ 32.923787] ? SyS_exit+0x30/0x30 [ 32.927231] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 32.932053] ? do_syscall_64+0xb7/0x9d0 [ 32.936002] ? do_group_exit+0x430/0x430 [ 32.940050] SyS_exit_group+0x1d/0x20 [ 32.943835] do_syscall_64+0x29e/0x9d0 [ 32.947701] ? vmalloc_sync_all+0x30/0x30 [ 32.951826] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.956559] ? syscall_return_slowpath+0x5c0/0x5c0 [ 32.961464] ? syscall_return_slowpath+0x30f/0x5c0 [ 32.966381] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 32.971724] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.976545] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.981710] RIP: 0033:0x441989 [ 32.984874] RSP: 002b:00007ffcb380f1a8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 [ 32.992559] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441989 [ 32.999804] RDX: 00000000004418c0 RSI: 0000000000000001 RDI: 0000000000000001 [ 33.007050] RBP: 00000000004a35a9 R08: 0000000000000020 R09: 00000000006cd018 [ 33.014293] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffcb380f2a8 [ 33.021539] R13: 0000000000402710 R14: 0000000000000000 R15: 0000000000000000 [ 33.028798] [ 33.030402] Allocated by task 4425: [ 33.034009] save_stack+0x43/0xd0 [ 33.037445] kasan_kmalloc+0xc4/0xe0 [ 33.041132] __kmalloc_node_track_caller+0x47/0x70 [ 33.046041] __kmalloc_reserve.isra.38+0x3a/0xe0 [ 33.050772] __alloc_skb+0x14d/0x780 [ 33.054458] alloc_skb_with_frags+0x137/0x760 [ 33.058935] sock_alloc_send_pskb+0x87a/0xae0 [ 33.063406] packet_sendmsg+0x1bd1/0x6100 [ 33.067528] sock_sendmsg+0xd5/0x120 [ 33.071215] ___sys_sendmsg+0x805/0x940 [ 33.075173] __sys_sendmsg+0x115/0x270 [ 33.079036] SyS_sendmsg+0x29/0x30 [ 33.082554] do_syscall_64+0x29e/0x9d0 [ 33.086417] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.091574] [ 33.093176] Freed by task 4425: [ 33.096430] save_stack+0x43/0xd0 [ 33.099860] __kasan_slab_free+0x11a/0x170 [ 33.104069] kasan_slab_free+0xe/0x10 [ 33.107842] kfree+0xd9/0x260 [ 33.110925] skb_free_head+0x99/0xc0 [ 33.114611] skb_release_data+0x690/0x860 [ 33.118735] skb_release_all+0x4a/0x60 [ 33.122597] kfree_skb+0x195/0x560 [ 33.126114] ip6_tnl_start_xmit+0xa44/0x2290 [ 33.130496] dev_hard_start_xmit+0x264/0xc10 [ 33.134879] __dev_queue_xmit+0x2724/0x34c0 [ 33.139175] dev_queue_xmit+0x17/0x20 [ 33.142950] packet_sendmsg+0x411d/0x6100 [ 33.147075] sock_sendmsg+0xd5/0x120 [ 33.150766] ___sys_sendmsg+0x805/0x940 [ 33.154716] __sys_sendmsg+0x115/0x270 [ 33.158577] SyS_sendmsg+0x29/0x30 [ 33.162092] do_syscall_64+0x29e/0x9d0 [ 33.165953] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.171115] [ 33.172719] The buggy address belongs to the object at ffff8801b49bba40 [ 33.172719] which belongs to the cache kmalloc-512 of size 512 [ 33.185350] The buggy address is located 224 bytes inside of [ 33.185350] 512-byte region [ffff8801b49bba40, ffff8801b49bbc40) [ 33.197198] The buggy address belongs to the page: [ 33.202103] page:ffffea0006d26ec0 count:1 mapcount:0 mapping:ffff8801b49bb040 index:0x0 [ 33.210221] flags: 0x2fffc0000000100(slab) [ 33.214433] raw: 02fffc0000000100 ffff8801b49bb040 0000000000000000 0000000100000006 [ 33.222290] raw: ffffea0006d35160 ffffea0006d89fa0 ffff8801dac00940 0000000000000000 [ 33.230153] page dumped because: kasan: bad access detected [ 33.235835] [ 33.237433] Memory state around the buggy address: [ 33.242335] ffff8801b49bba00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 33.249668] ffff8801b49bba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.257001] >ffff8801b49bbb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.264339] ^ [ 33.268723] ffff8801b49bbb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.276058] ffff8801b49bbc00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 33.283385] ================================================================== [ 33.290716] Disabling lock debugging due to kernel taint [ 33.296403] Kernel panic - not syncing: panic_on_warn set ... [ 33.296403] [ 33.303767] CPU: 0 PID: 4425 Comm: syzkaller487790 Tainted: G B 4.16.0+ #17 [ 33.312077] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.321403] Call Trace: [ 33.323969] dump_stack+0x1b9/0x294 [ 33.327571] ? dump_stack_print_info.cold.2+0x52/0x52 [ 33.332750] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 33.337481] ? skb_release_data+0xd0/0x860 [ 33.341694] panic+0x22f/0x4de [ 33.344863] ? add_taint.cold.5+0x16/0x16 [ 33.348988] ? do_raw_spin_unlock+0x9e/0x2e0 [ 33.353373] ? do_raw_spin_unlock+0x9e/0x2e0 [ 33.357758] ? skb_release_data+0x19b/0x860 [ 33.362055] kasan_end_report+0x47/0x4f [ 33.366008] kasan_report.cold.7+0xc9/0x2f5 [ 33.370311] check_memory_region+0x13e/0x1b0 [ 33.374695] kasan_check_write+0x14/0x20 [ 33.378728] skb_release_data+0x19b/0x860 [ 33.382850] ? skb_tx_error+0x2f0/0x2f0 [ 33.386797] ? kasan_check_read+0x11/0x20 [ 33.390919] ? rcu_is_watching+0x85/0x140 [ 33.395042] ? kasan_check_write+0x14/0x20 [ 33.399260] ? sock_rmem_free+0x6f/0x90 [ 33.403209] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 33.408723] skb_release_all+0x4a/0x60 [ 33.412587] kfree_skb+0x195/0x560 [ 33.416104] ? skb_queue_purge+0x19/0x40 [ 33.420140] ? __kfree_skb+0x20/0x20 [ 33.423830] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 33.428387] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 33.433464] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.438453] ? trace_hardirqs_on+0xd/0x10 [ 33.442575] ? skb_dequeue+0x12f/0x180 [ 33.446436] skb_queue_purge+0x19/0x40 [ 33.450301] packet_sock_destruct+0x93/0x290 [ 33.454685] ? packet_mm_close+0xc0/0xc0 [ 33.458720] ? graph_lock+0x170/0x170 [ 33.462496] ? __free_object+0x16e/0x330 [ 33.466531] ? __list_del_entry_valid.cold.1+0x58/0x58 [ 33.471782] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 33.476337] ? packet_mm_close+0xc0/0xc0 [ 33.480370] __sk_destruct+0xff/0xa40 [ 33.484145] ? sock_warn_obsolete_bsdism+0xb0/0xb0 [ 33.489049] ? graph_lock+0x170/0x170 [ 33.492824] ? lock_downgrade+0x8e0/0x8e0 [ 33.496944] ? __lock_is_held+0xb5/0x140 [ 33.500980] ? kasan_check_read+0x11/0x20 [ 33.505104] ? do_raw_spin_unlock+0x9e/0x2e0 [ 33.509485] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 33.514043] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 33.519127] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 33.524641] ? refcount_sub_and_test+0x212/0x330 [ 33.529373] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 33.534112] ? refcount_inc_not_zero+0x2d0/0x2d0 [ 33.538843] ? pcpu_free_area+0xa90/0xa90 [ 33.542966] sk_destruct+0x78/0x90 [ 33.546481] __sk_free+0x22e/0x340 [ 33.549995] sk_free+0x42/0x50 [ 33.553168] packet_release+0xa18/0xd50 [ 33.557113] ? lock_downgrade+0x8e0/0x8e0 [ 33.561236] ? packet_lookup_frame+0x270/0x270 [ 33.565792] ? cpumask_weight.constprop.5+0x44/0x44 [ 33.570782] ? do_raw_spin_lock+0xc1/0x200 [ 33.574992] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 33.580506] ? locks_remove_file+0x3f7/0x5a0 [ 33.584887] ? fcntl_setlk+0x1020/0x1020 [ 33.588921] ? fsnotify+0x415/0x1100 [ 33.592618] ? fsnotify_first_mark+0x330/0x330 [ 33.597175] sock_release+0x96/0x1b0 [ 33.600861] ? sock_alloc_file+0x4e0/0x4e0 [ 33.605068] sock_close+0x16/0x20 [ 33.608495] __fput+0x34d/0x890 [ 33.611748] ? fput+0x1a0/0x1a0 [ 33.615011] ? check_same_owner+0x320/0x320 [ 33.619313] ____fput+0x15/0x20 [ 33.622566] task_work_run+0x1e4/0x290 [ 33.626427] ? task_work_cancel+0x240/0x240 [ 33.630734] ? switch_task_namespaces+0xbd/0xd0 [ 33.635388] do_exit+0x1aee/0x2730 [ 33.638900] ? find_held_lock+0x36/0x1c0 [ 33.642940] ? mm_update_next_owner+0x980/0x980 [ 33.647585] ? kasan_check_read+0x11/0x20 [ 33.651711] ? rcu_is_watching+0x85/0x140 [ 33.655832] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 33.661000] ? tun_get+0x22b/0x360 [ 33.664519] ? tun_chr_close+0x60/0x60 [ 33.668382] ? tun_chr_write_iter+0x110/0x154 [ 33.672854] ? fsnotify+0x415/0x1100 [ 33.676545] ? kasan_check_read+0x11/0x20 [ 33.680667] ? rcu_is_watching+0x85/0x140 [ 33.684788] ? rcu_pm_notify+0xc0/0xc0 [ 33.688651] ? vfs_writev+0x255/0x330 [ 33.692424] ? rcu_read_lock_sched_held+0x108/0x120 [ 33.697412] ? kfree+0x1e9/0x260 [ 33.700751] ? vfs_writev+0xfc/0x330 [ 33.704439] ? vfs_iter_write+0xb0/0xb0 [ 33.708392] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 33.713903] ? sockfd_lookup_light+0xc5/0x160 [ 33.718372] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 33.723883] ? __fdget_pos+0xd6/0x1e0 [ 33.727655] ? __fdget_raw+0x20/0x20 [ 33.731345] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 33.736858] ? __sys_setsockopt+0x24f/0x390 [ 33.741155] do_group_exit+0x16f/0x430 [ 33.745023] ? SyS_exit+0x30/0x30 [ 33.748457] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 33.753272] ? do_syscall_64+0xb7/0x9d0 [ 33.757230] ? do_group_exit+0x430/0x430 [ 33.761266] SyS_exit_group+0x1d/0x20 [ 33.765045] do_syscall_64+0x29e/0x9d0 [ 33.768907] ? vmalloc_sync_all+0x30/0x30 [ 33.773035] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 33.777765] ? syscall_return_slowpath+0x5c0/0x5c0 [ 33.782670] ? syscall_return_slowpath+0x30f/0x5c0 [ 33.787595] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 33.792934] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.797750] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 33.802923] RIP: 0033:0x441989 [ 33.806088] RSP: 002b:00007ffcb380f1a8 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7 [ 33.813777] RAX: ffffffffffffffda RBX: 000000000000001b RCX: 0000000000441989 [ 33.821027] RDX: 00000000004418c0 RSI: 0000000000000001 RDI: 0000000000000001 [ 33.828271] RBP: 00000000004a35a9 R08: 0000000000000020 R09: 00000000006cd018 [ 33.835938] R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffcb380f2a8 [ 33.843182] R13: 0000000000402710 R14: 0000000000000000 R15: 0000000000000000 [ 33.850836] Dumping ftrace buffer: [ 33.854347] (ftrace buffer empty) [ 33.858028] Kernel Offset: disabled [ 33.861631] Rebooting in 86400 seconds..