[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.6' (ECDSA) to the list of known hosts. 2020/06/18 06:14:46 fuzzer started 2020/06/18 06:14:46 connecting to host at 10.128.0.26:42969 2020/06/18 06:14:46 checking machine... 2020/06/18 06:14:46 checking revisions... 2020/06/18 06:14:46 testing simple program... syzkaller login: [ 61.710955][ T6820] IPVS: ftp: loaded support on port[0] = 21 2020/06/18 06:14:46 building call list... [ 62.016501][ T26] tipc: TX() has been purged, node left! [ 62.578391][ T26] ================================================================== [ 62.586713][ T26] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.594691][ T26] Write of size 1 at addr ffff88809f96d1e4 by task kworker/u4:2/26 [ 62.602746][ T26] [ 62.605076][ T26] CPU: 1 PID: 26 Comm: kworker/u4:2 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.614170][ T26] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.624312][ T26] Workqueue: netns cleanup_net [ 62.629069][ T26] Call Trace: [ 62.632362][ T26] dump_stack+0x18f/0x20d [ 62.636693][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.642231][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.647769][ T26] ? afs_put_call+0xa40/0xa40 [ 62.652444][ T26] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.659676][ T26] ? vprintk_func+0x97/0x1a6 [ 62.664367][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.669914][ T26] kasan_report.cold+0x1f/0x37 [ 62.674688][ T26] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.680318][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.685924][ T26] afs_wake_up_async_call+0x6aa/0x770 [ 62.691295][ T26] ? afs_close_socket+0x320/0x320 [ 62.696328][ T26] ? afs_put_call+0xa40/0xa40 [ 62.702071][ T26] rxrpc_notify_socket+0x1db/0x5d0 [ 62.707535][ T26] ? afs_put_call+0xa40/0xa40 [ 62.712224][ T26] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.718640][ T26] rxrpc_call_completed+0xca/0xf0 [ 62.723679][ T26] rxrpc_discard_prealloc+0x781/0xab0 [ 62.729058][ T26] ? lock_sock_nested+0x94/0x110 [ 62.734001][ T26] rxrpc_listen+0x147/0x360 [ 62.738519][ T26] afs_close_socket+0x95/0x320 [ 62.743279][ T26] ? afs_purge_servers+0x16d/0x300 [ 62.748388][ T26] ? afs_rx_discard_new_call+0x50/0x50 [ 62.753853][ T26] ? init_wait_var_entry+0x200/0x200 [ 62.759144][ T26] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.764778][ T26] ? check_preemption_disabled+0x38/0x220 [ 62.770503][ T26] afs_net_exit+0x1bc/0x310 [ 62.775006][ T26] ? afs_net_init+0xe30/0xe30 [ 62.779683][ T26] ops_exit_list.isra.0+0xa8/0x150 [ 62.784802][ T26] cleanup_net+0x511/0xa50 [ 62.789308][ T26] ? unregister_pernet_device+0x70/0x70 [ 62.794859][ T26] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.800851][ T26] process_one_work+0x965/0x1690 [ 62.805817][ T26] ? lock_release+0x800/0x800 [ 62.810500][ T26] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.815970][ T26] ? rwlock_bug.part.0+0x90/0x90 [ 62.822683][ T26] worker_thread+0x96/0xe10 [ 62.827204][ T26] ? process_one_work+0x1690/0x1690 [ 62.832406][ T26] kthread+0x3b5/0x4a0 [ 62.836501][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.842218][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.847942][ T26] ret_from_fork+0x1f/0x30 [ 62.852368][ T26] [ 62.855221][ T26] Allocated by task 6820: [ 62.859549][ T26] save_stack+0x1b/0x40 [ 62.863705][ T26] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.869335][ T26] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.874725][ T26] afs_alloc_call+0x55/0x630 [ 62.879318][ T26] afs_charge_preallocation+0xe9/0x2d0 [ 62.884775][ T26] afs_open_socket+0x292/0x360 [ 62.890327][ T26] afs_net_init+0xa6c/0xe30 [ 62.894828][ T26] ops_init+0xaf/0x420 [ 62.898911][ T26] setup_net+0x2de/0x860 [ 62.903154][ T26] copy_net_ns+0x293/0x590 [ 62.907570][ T26] create_new_namespaces+0x3fb/0xb30 [ 62.912850][ T26] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.918487][ T26] ksys_unshare+0x43d/0x8e0 [ 62.922992][ T26] __x64_sys_unshare+0x2d/0x40 [ 62.927752][ T26] do_syscall_64+0x60/0xe0 [ 62.932177][ T26] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.938054][ T26] [ 62.940376][ T26] Freed by task 26: [ 62.944183][ T26] save_stack+0x1b/0x40 [ 62.948338][ T26] __kasan_slab_free+0xf7/0x140 [ 62.953197][ T26] kfree+0x109/0x2b0 [ 62.957110][ T26] afs_put_call+0x585/0xa40 [ 62.961636][ T26] rxrpc_discard_prealloc+0x764/0xab0 [ 62.967009][ T26] rxrpc_listen+0x147/0x360 [ 62.971550][ T26] afs_close_socket+0x95/0x320 [ 62.976309][ T26] afs_net_exit+0x1bc/0x310 [ 62.980808][ T26] ops_exit_list.isra.0+0xa8/0x150 [ 62.985915][ T26] cleanup_net+0x511/0xa50 [ 62.990330][ T26] process_one_work+0x965/0x1690 [ 62.995266][ T26] worker_thread+0x96/0xe10 [ 62.999763][ T26] kthread+0x3b5/0x4a0 [ 63.003834][ T26] ret_from_fork+0x1f/0x30 [ 63.008236][ T26] [ 63.010563][ T26] The buggy address belongs to the object at ffff88809f96d000 [ 63.010563][ T26] which belongs to the cache kmalloc-1k of size 1024 [ 63.024615][ T26] The buggy address is located 484 bytes inside of [ 63.024615][ T26] 1024-byte region [ffff88809f96d000, ffff88809f96d400) [ 63.038090][ T26] The buggy address belongs to the page: [ 63.043734][ T26] page:ffffea00027e5b40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 63.052839][ T26] flags: 0xfffe0000000200(slab) [ 63.057697][ T26] raw: 00fffe0000000200 ffffea0002508888 ffffea00029801c8 ffff8880aa000c40 [ 63.067325][ T26] raw: 0000000000000000 ffff88809f96d000 0000000100000002 0000000000000000 [ 63.075897][ T26] page dumped because: kasan: bad access detected [ 63.082298][ T26] [ 63.084618][ T26] Memory state around the buggy address: [ 63.090253][ T26] ffff88809f96d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.098352][ T26] ffff88809f96d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.106765][ T26] >ffff88809f96d180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.114819][ T26] ^ [ 63.122010][ T26] ffff88809f96d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.130130][ T26] ffff88809f96d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.138182][ T26] ================================================================== [ 63.146234][ T26] Disabling lock debugging due to kernel taint [ 63.152467][ T26] Kernel panic - not syncing: panic_on_warn set ... [ 63.159081][ T26] CPU: 1 PID: 26 Comm: kworker/u4:2 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 63.168739][ T26] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.179583][ T26] Workqueue: netns cleanup_net [ 63.184349][ T26] Call Trace: [ 63.187647][ T26] dump_stack+0x18f/0x20d [ 63.191978][ T26] ? afs_wake_up_async_call+0x670/0x770 [ 63.197626][ T26] ? afs_put_call+0xa40/0xa40 [ 63.202312][ T26] panic+0x2e3/0x75c [ 63.206219][ T26] ? __warn_printk+0xf3/0xf3 [ 63.210966][ T26] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.217238][ T26] ? trace_hardirqs_on+0x55/0x220 [ 63.222250][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.227784][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.233310][ T26] ? afs_put_call+0xa40/0xa40 [ 63.237967][ T26] end_report+0x4d/0x53 [ 63.242113][ T26] kasan_report.cold+0xd/0x37 [ 63.246790][ T26] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.252412][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.257949][ T26] afs_wake_up_async_call+0x6aa/0x770 [ 63.263305][ T26] ? afs_close_socket+0x320/0x320 [ 63.268318][ T26] ? afs_put_call+0xa40/0xa40 [ 63.273142][ T26] rxrpc_notify_socket+0x1db/0x5d0 [ 63.278260][ T26] ? afs_put_call+0xa40/0xa40 [ 63.282932][ T26] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.289775][ T26] rxrpc_call_completed+0xca/0xf0 [ 63.294798][ T26] rxrpc_discard_prealloc+0x781/0xab0 [ 63.300361][ T26] ? lock_sock_nested+0x94/0x110 [ 63.305295][ T26] rxrpc_listen+0x147/0x360 [ 63.309796][ T26] afs_close_socket+0x95/0x320 [ 63.314606][ T26] ? afs_purge_servers+0x16d/0x300 [ 63.319844][ T26] ? afs_rx_discard_new_call+0x50/0x50 [ 63.325407][ T26] ? init_wait_var_entry+0x200/0x200 [ 63.330792][ T26] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.336419][ T26] ? check_preemption_disabled+0x38/0x220 [ 63.342156][ T26] afs_net_exit+0x1bc/0x310 [ 63.346656][ T26] ? afs_net_init+0xe30/0xe30 [ 63.352018][ T26] ops_exit_list.isra.0+0xa8/0x150 [ 63.357148][ T26] cleanup_net+0x511/0xa50 [ 63.361610][ T26] ? unregister_pernet_device+0x70/0x70 [ 63.367261][ T26] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.373248][ T26] process_one_work+0x965/0x1690 [ 63.378243][ T26] ? lock_release+0x800/0x800 [ 63.383433][ T26] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.388788][ T26] ? rwlock_bug.part.0+0x90/0x90 [ 63.393853][ T26] worker_thread+0x96/0xe10 [ 63.398578][ T26] ? process_one_work+0x1690/0x1690 [ 63.403764][ T26] kthread+0x3b5/0x4a0 [ 63.407829][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.413737][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.419454][ T26] ret_from_fork+0x1f/0x30 [ 63.425286][ T26] Kernel Offset: disabled [ 63.429715][ T26] Rebooting in 86400 seconds..