Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.167' (ECDSA) to the list of known hosts. 2020/06/19 05:16:55 fuzzer started 2020/06/19 05:16:55 connecting to host at 10.128.0.26:33271 2020/06/19 05:16:55 checking machine... 2020/06/19 05:16:55 checking revisions... 2020/06/19 05:16:55 testing simple program... syzkaller login: [ 59.237221][ T6829] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 05:16:56 building call list... [ 59.526255][ T765] tipc: TX() has been purged, node left! [ 60.108254][ T765] ================================================================== [ 60.116488][ T765] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 60.124372][ T765] Write of size 1 at addr ffff8880a48749e4 by task kworker/u4:5/765 [ 60.132337][ T765] [ 60.134676][ T765] CPU: 1 PID: 765 Comm: kworker/u4:5 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.142986][ T765] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.153167][ T765] Workqueue: netns cleanup_net [ 60.157939][ T765] Call Trace: [ 60.161235][ T765] dump_stack+0x18f/0x20d [ 60.165564][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.171103][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.176717][ T765] ? afs_put_call+0xa40/0xa40 [ 60.181410][ T765] print_address_description.constprop.0.cold+0xd3/0x413 [ 60.188443][ T765] ? vprintk_func+0x97/0x1a6 [ 60.193035][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.198583][ T765] kasan_report.cold+0x1f/0x37 [ 60.203349][ T765] ? rcu_read_lock_held_common+0x51/0xa0 [ 60.208975][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.214520][ T765] afs_wake_up_async_call+0x6aa/0x770 [ 60.219890][ T765] ? afs_close_socket+0x320/0x320 [ 60.224914][ T765] ? afs_put_call+0xa40/0xa40 [ 60.229589][ T765] rxrpc_notify_socket+0x1db/0x5d0 [ 60.234704][ T765] ? afs_put_call+0xa40/0xa40 [ 60.239379][ T765] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.245802][ T765] rxrpc_call_completed+0xca/0xf0 [ 60.250830][ T765] rxrpc_discard_prealloc+0x781/0xab0 [ 60.256205][ T765] ? lock_sock_nested+0x94/0x110 [ 60.261147][ T765] rxrpc_listen+0x147/0x360 [ 60.265653][ T765] afs_close_socket+0x95/0x320 [ 60.270933][ T765] ? afs_purge_servers+0x16d/0x300 [ 60.276044][ T765] ? afs_rx_discard_new_call+0x50/0x50 [ 60.281507][ T765] ? init_wait_var_entry+0x200/0x200 [ 60.286805][ T765] ? rcu_read_lock_held_common+0xa0/0xa0 [ 60.292437][ T765] ? check_preemption_disabled+0x38/0x220 [ 60.298723][ T765] afs_net_exit+0x1bc/0x310 [ 60.303225][ T765] ? afs_net_init+0xe30/0xe30 [ 60.307898][ T765] ops_exit_list.isra.0+0xa8/0x150 [ 60.313016][ T765] cleanup_net+0x511/0xa50 [ 60.317434][ T765] ? unregister_pernet_device+0x70/0x70 [ 60.323069][ T765] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 60.329229][ T765] process_one_work+0x965/0x1690 [ 60.334178][ T765] ? lock_release+0x800/0x800 [ 60.338855][ T765] ? pwq_dec_nr_in_flight+0x310/0x310 [ 60.344229][ T765] ? rwlock_bug.part.0+0x90/0x90 [ 60.349178][ T765] worker_thread+0x96/0xe10 [ 60.353694][ T765] ? process_one_work+0x1690/0x1690 [ 60.358890][ T765] kthread+0x3b5/0x4a0 [ 60.362972][ T765] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.368684][ T765] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.374491][ T765] ret_from_fork+0x1f/0x30 [ 60.378909][ T765] [ 60.381229][ T765] Allocated by task 6829: [ 60.385706][ T765] save_stack+0x1b/0x40 [ 60.389872][ T765] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 60.395520][ T765] kmem_cache_alloc_trace+0x153/0x7d0 [ 60.400884][ T765] afs_alloc_call+0x55/0x630 [ 60.405467][ T765] afs_charge_preallocation+0xe9/0x2d0 [ 60.410921][ T765] afs_open_socket+0x292/0x360 [ 60.415766][ T765] afs_net_init+0xa6c/0xe30 [ 60.420286][ T765] ops_init+0xaf/0x420 [ 60.424360][ T765] setup_net+0x2de/0x860 [ 60.428605][ T765] copy_net_ns+0x293/0x590 [ 60.433024][ T765] create_new_namespaces+0x3fb/0xb30 [ 60.438306][ T765] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 60.443931][ T765] ksys_unshare+0x43d/0x8e0 [ 60.448429][ T765] __x64_sys_unshare+0x2d/0x40 [ 60.453188][ T765] do_syscall_64+0x60/0xe0 [ 60.457601][ T765] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 60.463477][ T765] [ 60.465795][ T765] Freed by task 765: [ 60.469693][ T765] save_stack+0x1b/0x40 [ 60.473856][ T765] __kasan_slab_free+0xf7/0x140 [ 60.478704][ T765] kfree+0x109/0x2b0 [ 60.482597][ T765] afs_put_call+0x585/0xa40 [ 60.487099][ T765] rxrpc_discard_prealloc+0x764/0xab0 [ 60.492469][ T765] rxrpc_listen+0x147/0x360 [ 60.496965][ T765] afs_close_socket+0x95/0x320 [ 60.501722][ T765] afs_net_exit+0x1bc/0x310 [ 60.506218][ T765] ops_exit_list.isra.0+0xa8/0x150 [ 60.511321][ T765] cleanup_net+0x511/0xa50 [ 60.515731][ T765] process_one_work+0x965/0x1690 [ 60.520659][ T765] worker_thread+0x96/0xe10 [ 60.525158][ T765] kthread+0x3b5/0x4a0 [ 60.529231][ T765] ret_from_fork+0x1f/0x30 [ 60.533635][ T765] [ 60.535962][ T765] The buggy address belongs to the object at ffff8880a4874800 [ 60.535962][ T765] which belongs to the cache kmalloc-1k of size 1024 [ 60.550013][ T765] The buggy address is located 484 bytes inside of [ 60.550013][ T765] 1024-byte region [ffff8880a4874800, ffff8880a4874c00) [ 60.563359][ T765] The buggy address belongs to the page: [ 60.568993][ T765] page:ffffea0002921d00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 60.578096][ T765] flags: 0xfffe0000000200(slab) [ 60.582963][ T765] raw: 00fffe0000000200 ffffea0002494608 ffffea00025e3ec8 ffff8880aa000c40 [ 60.591584][ T765] raw: 0000000000000000 ffff8880a4874000 0000000100000002 0000000000000000 [ 60.600173][ T765] page dumped because: kasan: bad access detected [ 60.606636][ T765] [ 60.608971][ T765] Memory state around the buggy address: [ 60.614615][ T765] ffff8880a4874880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.622675][ T765] ffff8880a4874900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.630748][ T765] >ffff8880a4874980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.638802][ T765] ^ [ 60.646007][ T765] ffff8880a4874a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.654154][ T765] ffff8880a4874a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.662233][ T765] ================================================================== [ 60.670284][ T765] Disabling lock debugging due to kernel taint [ 60.676485][ T765] Kernel panic - not syncing: panic_on_warn set ... [ 60.683067][ T765] CPU: 1 PID: 765 Comm: kworker/u4:5 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 60.692768][ T765] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.702815][ T765] Workqueue: netns cleanup_net [ 60.707569][ T765] Call Trace: [ 60.710854][ T765] dump_stack+0x18f/0x20d [ 60.715177][ T765] ? afs_wake_up_async_call+0x680/0x770 [ 60.720710][ T765] ? afs_put_call+0xa40/0xa40 [ 60.725382][ T765] panic+0x2e3/0x75c [ 60.729270][ T765] ? __warn_printk+0xf3/0xf3 [ 60.734375][ T765] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 60.740530][ T765] ? trace_hardirqs_on+0x55/0x220 [ 60.745549][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.751084][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.756632][ T765] ? afs_put_call+0xa40/0xa40 [ 60.761298][ T765] end_report+0x4d/0x53 [ 60.765442][ T765] kasan_report.cold+0xd/0x37 [ 60.770196][ T765] ? rcu_read_lock_held_common+0x51/0xa0 [ 60.775819][ T765] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.781357][ T765] afs_wake_up_async_call+0x6aa/0x770 [ 60.786720][ T765] ? afs_close_socket+0x320/0x320 [ 60.791744][ T765] ? afs_put_call+0xa40/0xa40 [ 60.796417][ T765] rxrpc_notify_socket+0x1db/0x5d0 [ 60.801629][ T765] ? afs_put_call+0xa40/0xa40 [ 60.806300][ T765] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.812709][ T765] rxrpc_call_completed+0xca/0xf0 [ 60.817726][ T765] rxrpc_discard_prealloc+0x781/0xab0 [ 60.823090][ T765] ? lock_sock_nested+0x94/0x110 [ 60.828018][ T765] rxrpc_listen+0x147/0x360 [ 60.832513][ T765] afs_close_socket+0x95/0x320 [ 60.837266][ T765] ? afs_purge_servers+0x16d/0x300 [ 60.842368][ T765] ? afs_rx_discard_new_call+0x50/0x50 [ 60.847921][ T765] ? init_wait_var_entry+0x200/0x200 [ 60.853219][ T765] ? rcu_read_lock_held_common+0xa0/0xa0 [ 60.858854][ T765] ? check_preemption_disabled+0x38/0x220 [ 60.864589][ T765] afs_net_exit+0x1bc/0x310 [ 60.869081][ T765] ? afs_net_init+0xe30/0xe30 [ 60.873750][ T765] ops_exit_list.isra.0+0xa8/0x150 [ 60.878858][ T765] cleanup_net+0x511/0xa50 [ 60.883268][ T765] ? unregister_pernet_device+0x70/0x70 [ 60.888806][ T765] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 60.894778][ T765] process_one_work+0x965/0x1690 [ 60.899731][ T765] ? lock_release+0x800/0x800 [ 60.904920][ T765] ? pwq_dec_nr_in_flight+0x310/0x310 [ 60.910290][ T765] ? rwlock_bug.part.0+0x90/0x90 [ 60.915426][ T765] worker_thread+0x96/0xe10 [ 60.919929][ T765] ? process_one_work+0x1690/0x1690 [ 60.925119][ T765] kthread+0x3b5/0x4a0 [ 60.929285][ T765] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.934992][ T765] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.940704][ T765] ret_from_fork+0x1f/0x30 [ 60.945731][ T765] Kernel Offset: disabled [ 60.950205][ T765] Rebooting in 86400 seconds..