[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.142' (ECDSA) to the list of known hosts. 2020/06/25 18:48:36 fuzzer started 2020/06/25 18:48:37 connecting to host at 10.128.0.26:38263 2020/06/25 18:48:37 checking machine... 2020/06/25 18:48:37 checking revisions... 2020/06/25 18:48:37 testing simple program... syzkaller login: [ 60.064512][ T6824] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 18:48:37 building call list... [ 60.415374][ T213] tipc: TX() has been purged, node left! [ 60.917661][ T213] ================================================================== [ 60.926025][ T213] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 60.933920][ T213] Write of size 1 at addr ffff888093a6d1e4 by task kworker/u4:4/213 [ 60.941899][ T213] [ 60.944240][ T213] CPU: 1 PID: 213 Comm: kworker/u4:4 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.953006][ T213] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.963068][ T213] Workqueue: netns cleanup_net [ 60.968053][ T213] Call Trace: [ 60.971362][ T213] dump_stack+0x18f/0x20d [ 60.975707][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.981430][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.986976][ T213] ? afs_put_call+0x440/0x440 [ 60.991653][ T213] print_address_description.constprop.0.cold+0xae/0x436 [ 60.998687][ T213] ? vprintk_func+0x97/0x1a6 [ 61.003282][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.008828][ T213] kasan_report.cold+0x1f/0x37 [ 61.014465][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.020023][ T213] afs_wake_up_async_call+0x430/0x4a0 [ 61.025397][ T213] ? afs_close_socket+0x320/0x320 [ 61.030604][ T213] rxrpc_notify_socket+0x1db/0x5d0 [ 61.035760][ T213] ? afs_put_call+0x440/0x440 [ 61.040619][ T213] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.047467][ T213] rxrpc_call_completed+0xd0/0xf0 [ 61.052494][ T213] rxrpc_discard_prealloc+0x777/0xab0 [ 61.057868][ T213] ? lock_sock_nested+0x94/0x110 [ 61.062820][ T213] rxrpc_listen+0x11c/0x330 [ 61.067410][ T213] afs_close_socket+0x95/0x320 [ 61.072170][ T213] ? afs_purge_servers+0x16d/0x300 [ 61.077278][ T213] ? afs_rx_discard_new_call+0x50/0x50 [ 61.082739][ T213] ? init_wait_var_entry+0x200/0x200 [ 61.089069][ T213] ? check_preemption_disabled+0x38/0x220 [ 61.094792][ T213] afs_net_exit+0x1bc/0x310 [ 61.099473][ T213] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.105099][ T213] ops_exit_list+0xb0/0x160 [ 61.109606][ T213] cleanup_net+0x4ea/0xa00 [ 61.114017][ T213] ? __schedule+0x887/0x1eb0 [ 61.118607][ T213] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.123980][ T213] ? check_preemption_disabled+0x38/0x220 [ 61.129717][ T213] process_one_work+0x94c/0x1670 [ 61.135706][ T213] ? lock_release+0x8d0/0x8d0 [ 61.140379][ T213] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.146045][ T213] ? rwlock_bug.part.0+0x90/0x90 [ 61.150996][ T213] worker_thread+0x64c/0x1120 [ 61.155878][ T213] ? process_one_work+0x1670/0x1670 [ 61.161077][ T213] kthread+0x3b5/0x4a0 [ 61.165404][ T213] ? __kthread_bind_mask+0xc0/0xc0 [ 61.171306][ T213] ? __kthread_bind_mask+0xc0/0xc0 [ 61.176445][ T213] ret_from_fork+0x1f/0x30 [ 61.183945][ T213] [ 61.186271][ T213] Allocated by task 6824: [ 61.190656][ T213] save_stack+0x1b/0x40 [ 61.194821][ T213] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 61.200674][ T213] kmem_cache_alloc_trace+0x14f/0x2d0 [ 61.206659][ T213] afs_alloc_call+0x4f/0x360 [ 61.211530][ T213] afs_charge_preallocation+0xe9/0x2d0 [ 61.217167][ T213] afs_open_socket+0x294/0x360 [ 61.221935][ T213] afs_net_init+0xa6c/0xe30 [ 61.226433][ T213] ops_init+0xaf/0x470 [ 61.230494][ T213] setup_net+0x2d8/0x850 [ 61.234844][ T213] copy_net_ns+0x2cf/0x5e0 [ 61.239345][ T213] create_new_namespaces+0x3f6/0xb10 [ 61.244727][ T213] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.250354][ T213] ksys_unshare+0x36c/0x9a0 [ 61.254851][ T213] __x64_sys_unshare+0x2d/0x40 [ 61.259704][ T213] do_syscall_64+0x60/0xe0 [ 61.264147][ T213] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.270118][ T213] [ 61.272536][ T213] Freed by task 213: [ 61.276437][ T213] save_stack+0x1b/0x40 [ 61.280589][ T213] __kasan_slab_free+0xf5/0x140 [ 61.285521][ T213] kfree+0x103/0x2c0 [ 61.289411][ T213] afs_put_call+0x345/0x440 [ 61.294110][ T213] rxrpc_discard_prealloc+0x75a/0xab0 [ 61.304368][ T213] rxrpc_listen+0x11c/0x330 [ 61.309317][ T213] afs_close_socket+0x95/0x320 [ 61.314093][ T213] afs_net_exit+0x1bc/0x310 [ 61.321607][ T213] ops_exit_list+0xb0/0x160 [ 61.326294][ T213] cleanup_net+0x4ea/0xa00 [ 61.330908][ T213] process_one_work+0x94c/0x1670 [ 61.336133][ T213] worker_thread+0x64c/0x1120 [ 61.340902][ T213] kthread+0x3b5/0x4a0 [ 61.344972][ T213] ret_from_fork+0x1f/0x30 [ 61.349816][ T213] [ 61.352149][ T213] The buggy address belongs to the object at ffff888093a6d000 [ 61.352149][ T213] which belongs to the cache kmalloc-1k of size 1024 [ 61.366481][ T213] The buggy address is located 484 bytes inside of [ 61.366481][ T213] 1024-byte region [ffff888093a6d000, ffff888093a6d400) [ 61.380325][ T213] The buggy address belongs to the page: [ 61.385992][ T213] page:ffffea00024e9b40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.395113][ T213] flags: 0xfffe0000000200(slab) [ 61.400057][ T213] raw: 00fffe0000000200 ffffea0002a4eec8 ffffea00028a4e48 ffff8880aa000c40 [ 61.409180][ T213] raw: 0000000000000000 ffff888093a6d000 0000000100000002 0000000000000000 [ 61.417862][ T213] page dumped because: kasan: bad access detected [ 61.424284][ T213] [ 61.426618][ T213] Memory state around the buggy address: [ 61.432737][ T213] ffff888093a6d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.441069][ T213] ffff888093a6d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.450363][ T213] >ffff888093a6d180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.458639][ T213] ^ [ 61.468252][ T213] ffff888093a6d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.476545][ T213] ffff888093a6d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.485339][ T213] ================================================================== [ 61.493653][ T213] Disabling lock debugging due to kernel taint [ 61.499850][ T213] Kernel panic - not syncing: panic_on_warn set ... [ 61.507919][ T213] CPU: 1 PID: 213 Comm: kworker/u4:4 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.517724][ T213] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.527995][ T213] Workqueue: netns cleanup_net [ 61.532762][ T213] Call Trace: [ 61.536061][ T213] dump_stack+0x18f/0x20d [ 61.540390][ T213] ? afs_wake_up_async_call+0x370/0x4a0 [ 61.545926][ T213] ? afs_put_call+0x440/0x440 [ 61.550598][ T213] panic+0x2e3/0x75c [ 61.554687][ T213] ? __warn_printk+0xf3/0xf3 [ 61.559374][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.565527][ T213] ? trace_hardirqs_on+0x55/0x220 [ 61.570639][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.576197][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.581919][ T213] ? afs_put_call+0x440/0x440 [ 61.586683][ T213] end_report+0x4d/0x53 [ 61.590950][ T213] kasan_report.cold+0xd/0x37 [ 61.595676][ T213] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.601311][ T213] afs_wake_up_async_call+0x430/0x4a0 [ 61.607042][ T213] ? afs_close_socket+0x320/0x320 [ 61.612346][ T213] rxrpc_notify_socket+0x1db/0x5d0 [ 61.617814][ T213] ? afs_put_call+0x440/0x440 [ 61.627000][ T213] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.633860][ T213] rxrpc_call_completed+0xd0/0xf0 [ 61.639169][ T213] rxrpc_discard_prealloc+0x777/0xab0 [ 61.644792][ T213] ? lock_sock_nested+0x94/0x110 [ 61.650271][ T213] rxrpc_listen+0x11c/0x330 [ 61.655386][ T213] afs_close_socket+0x95/0x320 [ 61.660432][ T213] ? afs_purge_servers+0x16d/0x300 [ 61.665642][ T213] ? afs_rx_discard_new_call+0x50/0x50 [ 61.672858][ T213] ? init_wait_var_entry+0x200/0x200 [ 61.678636][ T213] ? check_preemption_disabled+0x38/0x220 [ 61.684727][ T213] afs_net_exit+0x1bc/0x310 [ 61.689320][ T213] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.694954][ T213] ops_exit_list+0xb0/0x160 [ 61.710677][ T213] cleanup_net+0x4ea/0xa00 [ 61.715113][ T213] ? __schedule+0x887/0x1eb0 [ 61.720069][ T213] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.725456][ T213] ? check_preemption_disabled+0x38/0x220 [ 61.731184][ T213] process_one_work+0x94c/0x1670 [ 61.736398][ T213] ? lock_release+0x8d0/0x8d0 [ 61.741119][ T213] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.746521][ T213] ? rwlock_bug.part.0+0x90/0x90 [ 61.751728][ T213] worker_thread+0x64c/0x1120 [ 61.757038][ T213] ? process_one_work+0x1670/0x1670 [ 61.762345][ T213] kthread+0x3b5/0x4a0 [ 61.766467][ T213] ? __kthread_bind_mask+0xc0/0xc0 [ 61.774236][ T213] ? __kthread_bind_mask+0xc0/0xc0 [ 61.779353][ T213] ret_from_fork+0x1f/0x30 [ 61.787368][ T213] Kernel Offset: disabled [ 61.792064][ T213] Rebooting in 86400 seconds..