[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.21' (ECDSA) to the list of known hosts. 2020/06/19 08:27:14 fuzzer started 2020/06/19 08:27:15 connecting to host at 10.128.0.26:39867 2020/06/19 08:27:15 checking machine... 2020/06/19 08:27:15 checking revisions... 2020/06/19 08:27:15 testing simple program... syzkaller login: [ 60.106989][ T6808] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 08:27:15 building call list... [ 60.433424][ T85] tipc: TX() has been purged, node left! [ 60.915655][ T85] ================================================================== [ 60.924521][ T85] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 60.932535][ T85] Write of size 1 at addr ffff8880a025b1e4 by task kworker/u4:3/85 [ 60.940434][ T85] [ 60.942865][ T85] CPU: 0 PID: 85 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.951425][ T85] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.961583][ T85] Workqueue: netns cleanup_net [ 60.966805][ T85] Call Trace: [ 60.970114][ T85] dump_stack+0x18f/0x20d [ 60.975418][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.980981][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.986625][ T85] ? afs_put_call+0xa40/0xa40 [ 60.991409][ T85] print_address_description.constprop.0.cold+0xd3/0x413 [ 60.998476][ T85] ? vprintk_func+0x97/0x1a6 [ 61.003316][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.009054][ T85] kasan_report.cold+0x1f/0x37 [ 61.014029][ T85] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.019940][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.025629][ T85] afs_wake_up_async_call+0x6aa/0x770 [ 61.031232][ T85] ? afs_close_socket+0x320/0x320 [ 61.036381][ T85] ? afs_put_call+0xa40/0xa40 [ 61.041242][ T85] rxrpc_notify_socket+0x1db/0x5d0 [ 61.046477][ T85] ? afs_put_call+0xa40/0xa40 [ 61.051196][ T85] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.057630][ T85] rxrpc_call_completed+0xca/0xf0 [ 61.062713][ T85] rxrpc_discard_prealloc+0x781/0xab0 [ 61.068353][ T85] ? lock_sock_nested+0x94/0x110 [ 61.073316][ T85] rxrpc_listen+0x147/0x360 [ 61.077984][ T85] afs_close_socket+0x95/0x320 [ 61.083975][ T85] ? afs_purge_servers+0x16d/0x300 [ 61.089362][ T85] ? afs_rx_discard_new_call+0x50/0x50 [ 61.095011][ T85] ? init_wait_var_entry+0x200/0x200 [ 61.100507][ T85] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.106153][ T85] ? check_preemption_disabled+0x38/0x220 [ 61.112067][ T85] afs_net_exit+0x1bc/0x310 [ 61.116584][ T85] ? afs_net_init+0xe30/0xe30 [ 61.121572][ T85] ops_exit_list.isra.0+0xa8/0x150 [ 61.126892][ T85] cleanup_net+0x511/0xa50 [ 61.131676][ T85] ? unregister_pernet_device+0x70/0x70 [ 61.137761][ T85] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.144024][ T85] process_one_work+0x965/0x1690 [ 61.149380][ T85] ? lock_release+0x800/0x800 [ 61.154592][ T85] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.160009][ T85] ? rwlock_bug.part.0+0x90/0x90 [ 61.166111][ T85] worker_thread+0x96/0xe10 [ 61.171106][ T85] ? process_one_work+0x1690/0x1690 [ 61.176321][ T85] kthread+0x3b5/0x4a0 [ 61.180821][ T85] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.186825][ T85] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.192829][ T85] ret_from_fork+0x1f/0x30 [ 61.197268][ T85] [ 61.199705][ T85] Allocated by task 6808: [ 61.204131][ T85] save_stack+0x1b/0x40 [ 61.208297][ T85] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.213972][ T85] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.219878][ T85] afs_alloc_call+0x55/0x630 [ 61.224867][ T85] afs_charge_preallocation+0xe9/0x2d0 [ 61.230651][ T85] afs_open_socket+0x292/0x360 [ 61.235760][ T85] afs_net_init+0xa6c/0xe30 [ 61.240413][ T85] ops_init+0xaf/0x420 [ 61.244488][ T85] setup_net+0x2de/0x860 [ 61.249083][ T85] copy_net_ns+0x293/0x590 [ 61.253673][ T85] create_new_namespaces+0x3fb/0xb30 [ 61.259218][ T85] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.264950][ T85] ksys_unshare+0x43d/0x8e0 [ 61.269464][ T85] __x64_sys_unshare+0x2d/0x40 [ 61.274535][ T85] do_syscall_64+0x60/0xe0 [ 61.279119][ T85] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.285097][ T85] [ 61.287536][ T85] Freed by task 85: [ 61.291570][ T85] save_stack+0x1b/0x40 [ 61.295761][ T85] __kasan_slab_free+0xf7/0x140 [ 61.300996][ T85] kfree+0x109/0x2b0 [ 61.304900][ T85] afs_put_call+0x585/0xa40 [ 61.309922][ T85] rxrpc_discard_prealloc+0x764/0xab0 [ 61.315390][ T85] rxrpc_listen+0x147/0x360 [ 61.320164][ T85] afs_close_socket+0x95/0x320 [ 61.325367][ T85] afs_net_exit+0x1bc/0x310 [ 61.329961][ T85] ops_exit_list.isra.0+0xa8/0x150 [ 61.335181][ T85] cleanup_net+0x511/0xa50 [ 61.339796][ T85] process_one_work+0x965/0x1690 [ 61.345624][ T85] worker_thread+0x96/0xe10 [ 61.350608][ T85] kthread+0x3b5/0x4a0 [ 61.355078][ T85] ret_from_fork+0x1f/0x30 [ 61.359838][ T85] [ 61.362269][ T85] The buggy address belongs to the object at ffff8880a025b000 [ 61.362269][ T85] which belongs to the cache kmalloc-1k of size 1024 [ 61.377042][ T85] The buggy address is located 484 bytes inside of [ 61.377042][ T85] 1024-byte region [ffff8880a025b000, ffff8880a025b400) [ 61.391371][ T85] The buggy address belongs to the page: [ 61.397198][ T85] page:ffffea00028096c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.407788][ T85] flags: 0xfffe0000000200(slab) [ 61.412921][ T85] raw: 00fffe0000000200 ffffea0002645448 ffffea0002809ac8 ffff8880aa000c40 [ 61.421873][ T85] raw: 0000000000000000 ffff8880a025b000 0000000100000002 0000000000000000 [ 61.430768][ T85] page dumped because: kasan: bad access detected [ 61.437292][ T85] [ 61.439967][ T85] Memory state around the buggy address: [ 61.446139][ T85] ffff8880a025b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.454455][ T85] ffff8880a025b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.462525][ T85] >ffff8880a025b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.470788][ T85] ^ [ 61.478322][ T85] ffff8880a025b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.486989][ T85] ffff8880a025b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.495724][ T85] ================================================================== [ 61.503879][ T85] Disabling lock debugging due to kernel taint [ 61.510293][ T85] Kernel panic - not syncing: panic_on_warn set ... [ 61.517107][ T85] CPU: 0 PID: 85 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.528681][ T85] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.539704][ T85] Workqueue: netns cleanup_net [ 61.544725][ T85] Call Trace: [ 61.548118][ T85] dump_stack+0x18f/0x20d [ 61.552722][ T85] ? afs_wake_up_async_call+0x670/0x770 [ 61.558322][ T85] ? afs_put_call+0xa40/0xa40 [ 61.563267][ T85] panic+0x2e3/0x75c [ 61.567263][ T85] ? __warn_printk+0xf3/0xf3 [ 61.572318][ T85] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 61.579031][ T85] ? trace_hardirqs_on+0x55/0x220 [ 61.584240][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.591082][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.597236][ T85] ? afs_put_call+0xa40/0xa40 [ 61.602092][ T85] end_report+0x4d/0x53 [ 61.606355][ T85] kasan_report.cold+0xd/0x37 [ 61.611790][ T85] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.618358][ T85] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.626609][ T85] afs_wake_up_async_call+0x6aa/0x770 [ 61.632337][ T85] ? afs_close_socket+0x320/0x320 [ 61.637454][ T85] ? afs_put_call+0xa40/0xa40 [ 61.643119][ T85] rxrpc_notify_socket+0x1db/0x5d0 [ 61.650376][ T85] ? afs_put_call+0xa40/0xa40 [ 61.657551][ T85] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.665074][ T85] rxrpc_call_completed+0xca/0xf0 [ 61.671225][ T85] rxrpc_discard_prealloc+0x781/0xab0 [ 61.677410][ T85] ? lock_sock_nested+0x94/0x110 [ 61.683446][ T85] rxrpc_listen+0x147/0x360 [ 61.689344][ T85] afs_close_socket+0x95/0x320 [ 61.695269][ T85] ? afs_purge_servers+0x16d/0x300 [ 61.702479][ T85] ? afs_rx_discard_new_call+0x50/0x50 [ 61.708819][ T85] ? init_wait_var_entry+0x200/0x200 [ 61.714414][ T85] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.720151][ T85] ? check_preemption_disabled+0x38/0x220 [ 61.726568][ T85] afs_net_exit+0x1bc/0x310 [ 61.731903][ T85] ? afs_net_init+0xe30/0xe30 [ 61.737429][ T85] ops_exit_list.isra.0+0xa8/0x150 [ 61.743229][ T85] cleanup_net+0x511/0xa50 [ 61.748269][ T85] ? unregister_pernet_device+0x70/0x70 [ 61.755061][ T85] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.761677][ T85] process_one_work+0x965/0x1690 [ 61.767089][ T85] ? lock_release+0x800/0x800 [ 61.772054][ T85] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.778231][ T85] ? rwlock_bug.part.0+0x90/0x90 [ 61.784507][ T85] worker_thread+0x96/0xe10 [ 61.789880][ T85] ? process_one_work+0x1690/0x1690 [ 61.795437][ T85] kthread+0x3b5/0x4a0 [ 61.799842][ T85] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.805843][ T85] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.812028][ T85] ret_from_fork+0x1f/0x30 [ 61.818429][ T85] Kernel Offset: disabled [ 61.823182][ T85] Rebooting in 86400 seconds..