[ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.249' (ECDSA) to the list of known hosts. 2020/06/17 22:10:36 fuzzer started 2020/06/17 22:10:37 connecting to host at 10.128.0.26:34303 2020/06/17 22:10:37 checking machine... 2020/06/17 22:10:37 checking revisions... 2020/06/17 22:10:37 testing simple program... 2020/06/17 22:10:37 building call list... syzkaller login: [ 61.675729][ T6807] IPVS: ftp: loaded support on port[0] = 21 [ 61.978972][ T21] tipc: TX() has been purged, node left! [ 62.500972][ T21] ================================================================== [ 62.509200][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.517085][ T21] Write of size 1 at addr ffff88809f6041e4 by task kworker/u4:1/21 [ 62.524958][ T21] [ 62.527288][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.535513][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.545570][ T21] Workqueue: netns cleanup_net [ 62.550323][ T21] Call Trace: [ 62.553612][ T21] dump_stack+0x18f/0x20d [ 62.557940][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.563478][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.569018][ T21] ? afs_put_call+0xa40/0xa40 [ 62.573692][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.580718][ T21] ? vprintk_func+0x97/0x1a6 [ 62.585309][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.590850][ T21] kasan_report.cold+0x1f/0x37 [ 62.595619][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.601245][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.606800][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.612167][ T21] ? afs_close_socket+0x320/0x320 [ 62.617187][ T21] ? afs_put_call+0xa40/0xa40 [ 62.621867][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.627003][ T21] ? afs_put_call+0xa40/0xa40 [ 62.631676][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.638094][ T21] rxrpc_call_completed+0xca/0xf0 [ 62.643123][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 62.648498][ T21] ? lock_sock_nested+0x94/0x110 [ 62.653437][ T21] rxrpc_listen+0x147/0x360 [ 62.657959][ T21] afs_close_socket+0x95/0x320 [ 62.662722][ T21] ? afs_purge_servers+0x16d/0x300 [ 62.667831][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.673298][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.678587][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.684218][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.689938][ T21] afs_net_exit+0x1bc/0x310 [ 62.694435][ T21] ? afs_net_init+0xe30/0xe30 [ 62.699108][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.704222][ T21] cleanup_net+0x511/0xa50 [ 62.708711][ T21] ? unregister_pernet_device+0x70/0x70 [ 62.714271][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.720258][ T21] process_one_work+0x965/0x1690 [ 62.725206][ T21] ? lock_release+0x800/0x800 [ 62.729888][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.735291][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.740236][ T21] worker_thread+0x96/0xe10 [ 62.744751][ T21] ? process_one_work+0x1690/0x1690 [ 62.749948][ T21] kthread+0x3b5/0x4a0 [ 62.754016][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.759729][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.765462][ T21] ret_from_fork+0x1f/0x30 [ 62.769889][ T21] [ 62.772215][ T21] Allocated by task 6807: [ 62.776541][ T21] save_stack+0x1b/0x40 [ 62.780693][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.786318][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.791682][ T21] afs_alloc_call+0x55/0x630 [ 62.796268][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 62.801719][ T21] afs_open_socket+0x292/0x360 [ 62.806473][ T21] afs_net_init+0xa6c/0xe30 [ 62.810969][ T21] ops_init+0xaf/0x420 [ 62.815029][ T21] setup_net+0x2de/0x860 [ 62.819272][ T21] copy_net_ns+0x293/0x590 [ 62.823686][ T21] create_new_namespaces+0x3fb/0xb30 [ 62.828980][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.834616][ T21] ksys_unshare+0x43d/0x8e0 [ 62.839115][ T21] __x64_sys_unshare+0x2d/0x40 [ 62.843879][ T21] do_syscall_64+0x60/0xe0 [ 62.848293][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.854168][ T21] [ 62.856485][ T21] Freed by task 21: [ 62.860289][ T21] save_stack+0x1b/0x40 [ 62.864438][ T21] __kasan_slab_free+0xf7/0x140 [ 62.869282][ T21] kfree+0x109/0x2b0 [ 62.873173][ T21] afs_put_call+0x585/0xa40 [ 62.877675][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 62.883038][ T21] rxrpc_listen+0x147/0x360 [ 62.887541][ T21] afs_close_socket+0x95/0x320 [ 62.892295][ T21] afs_net_exit+0x1bc/0x310 [ 62.896800][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.901907][ T21] cleanup_net+0x511/0xa50 [ 62.906320][ T21] process_one_work+0x965/0x1690 [ 62.911253][ T21] worker_thread+0x96/0xe10 [ 62.915760][ T21] kthread+0x3b5/0x4a0 [ 62.919833][ T21] ret_from_fork+0x1f/0x30 [ 62.924240][ T21] [ 62.926565][ T21] The buggy address belongs to the object at ffff88809f604000 [ 62.926565][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 62.940629][ T21] The buggy address is located 484 bytes inside of [ 62.940629][ T21] 1024-byte region [ffff88809f604000, ffff88809f604400) [ 62.953991][ T21] The buggy address belongs to the page: [ 62.959626][ T21] page:ffffea00027d8100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.968739][ T21] flags: 0xfffe0000000200(slab) [ 62.973594][ T21] raw: 00fffe0000000200 ffffea00025564c8 ffffea00029f7308 ffff8880aa000c40 [ 62.982191][ T21] raw: 0000000000000000 ffff88809f604000 0000000100000002 0000000000000000 [ 62.990771][ T21] page dumped because: kasan: bad access detected [ 62.997177][ T21] [ 62.999508][ T21] Memory state around the buggy address: [ 63.005135][ T21] ffff88809f604080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.013194][ T21] ffff88809f604100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.021254][ T21] >ffff88809f604180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.029335][ T21] ^ [ 63.036527][ T21] ffff88809f604200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.044594][ T21] ffff88809f604280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.052668][ T21] ================================================================== [ 63.060723][ T21] Disabling lock debugging due to kernel taint [ 63.066919][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 63.073501][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 63.083112][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.093163][ T21] Workqueue: netns cleanup_net [ 63.097915][ T21] Call Trace: [ 63.101203][ T21] dump_stack+0x18f/0x20d [ 63.105530][ T21] ? afs_wake_up_async_call+0x680/0x770 [ 63.111067][ T21] ? afs_put_call+0xa40/0xa40 [ 63.115737][ T21] panic+0x2e3/0x75c [ 63.119637][ T21] ? __warn_printk+0xf3/0xf3 [ 63.124224][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.130379][ T21] ? trace_hardirqs_on+0x55/0x220 [ 63.135398][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.140939][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.146482][ T21] ? afs_put_call+0xa40/0xa40 [ 63.151156][ T21] end_report+0x4d/0x53 [ 63.155308][ T21] kasan_report.cold+0xd/0x37 [ 63.159984][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.165606][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.171143][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 63.176523][ T21] ? afs_close_socket+0x320/0x320 [ 63.181563][ T21] ? afs_put_call+0xa40/0xa40 [ 63.186257][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 63.191379][ T21] ? afs_put_call+0xa40/0xa40 [ 63.196155][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.202568][ T21] rxrpc_call_completed+0xca/0xf0 [ 63.207591][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 63.212963][ T21] ? lock_sock_nested+0x94/0x110 [ 63.217897][ T21] rxrpc_listen+0x147/0x360 [ 63.222394][ T21] afs_close_socket+0x95/0x320 [ 63.227151][ T21] ? afs_purge_servers+0x16d/0x300 [ 63.232256][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 63.237710][ T21] ? init_wait_var_entry+0x200/0x200 [ 63.243002][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.248630][ T21] ? check_preemption_disabled+0x38/0x220 [ 63.254342][ T21] afs_net_exit+0x1bc/0x310 [ 63.258836][ T21] ? afs_net_init+0xe30/0xe30 [ 63.263503][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 63.268615][ T21] cleanup_net+0x511/0xa50 [ 63.273024][ T21] ? unregister_pernet_device+0x70/0x70 [ 63.278566][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.284540][ T21] process_one_work+0x965/0x1690 [ 63.289475][ T21] ? lock_release+0x800/0x800 [ 63.294174][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.299543][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 63.304476][ T21] worker_thread+0x96/0xe10 [ 63.308977][ T21] ? process_one_work+0x1690/0x1690 [ 63.314167][ T21] kthread+0x3b5/0x4a0 [ 63.318226][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.323937][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.329655][ T21] ret_from_fork+0x1f/0x30 [ 63.335068][ T21] Kernel Offset: disabled [ 63.339417][ T21] Rebooting in 86400 seconds..