Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 34.837092] random: sshd: uninitialized urandom read (32 bytes read) [ 35.233601] audit: type=1400 audit(1536609548.764:6): avc: denied { map } for pid=5497 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 35.271823] sshd (5495) used greatest stack depth: 16776 bytes left [ 35.294554] random: sshd: uninitialized urandom read (32 bytes read) [ 35.881731] random: sshd: uninitialized urandom read (32 bytes read) [ 170.224190] random: sshd: uninitialized urandom read (32 bytes read) [ 170.381696] sshd (5506) used greatest stack depth: 16152 bytes left Warning: Permanently added '10.128.0.33' (ECDSA) to the list of known hosts. [ 175.916175] random: sshd: uninitialized urandom read (32 bytes read) [ 176.057395] audit: type=1400 audit(1536609689.584:7): avc: denied { map } for pid=5511 comm="syz-execprog" path="/root/syz-execprog" dev="sda1" ino=16479 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 2018/09/10 20:01:30 parsed 1 programs [ 176.553233] audit: type=1400 audit(1536609690.074:8): avc: denied { map } for pid=5511 comm="syz-execprog" path="/sys/kernel/debug/kcov" dev="debugfs" ino=80 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:debugfs_t:s0 tclass=file permissive=1 [ 177.311091] random: cc1: uninitialized urandom read (8 bytes read) 2018/09/10 20:01:32 executed programs: 0 [ 178.723905] audit: type=1400 audit(1536609692.244:9): avc: denied { map } for pid=5511 comm="syz-execprog" path="/root/syzkaller-shm586083697" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1 [ 178.759016] IPVS: ftp: loaded support on port[0] = 21 [ 179.010542] bridge0: port 1(bridge_slave_0) entered blocking state [ 179.017439] bridge0: port 1(bridge_slave_0) entered disabled state [ 179.024994] device bridge_slave_0 entered promiscuous mode [ 179.044229] bridge0: port 2(bridge_slave_1) entered blocking state [ 179.050778] bridge0: port 2(bridge_slave_1) entered disabled state [ 179.058348] device bridge_slave_1 entered promiscuous mode [ 179.077129] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 179.096539] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 179.146726] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 179.167423] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 179.244233] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 179.251831] team0: Port device team_slave_0 added [ 179.269026] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 179.276189] team0: Port device team_slave_1 added [ 179.293819] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 179.315008] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 179.335228] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 179.356591] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 179.505782] bridge0: port 2(bridge_slave_1) entered blocking state [ 179.512387] bridge0: port 2(bridge_slave_1) entered forwarding state [ 179.519406] bridge0: port 1(bridge_slave_0) entered blocking state [ 179.525804] bridge0: port 1(bridge_slave_0) entered forwarding state [ 180.048218] 8021q: adding VLAN 0 to HW filter on device bond0 [ 180.102025] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 180.154477] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 180.160656] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 180.169940] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 180.215734] 8021q: adding VLAN 0 to HW filter on device team0 [ 180.543365] [ 180.545057] ====================================================== [ 180.551355] WARNING: possible circular locking dependency detected [ 180.557651] 4.19.0-rc3+ #10 Not tainted [ 180.561645] ------------------------------------------------------ [ 180.567944] syz-executor0/5781 is trying to acquire lock: [ 180.573460] 00000000c7ac8e6b ((wq_completion)bond_dev->name){+.+.}, at: flush_workqueue+0x2db/0x1e10 [ 180.582736] [ 180.582736] but task is already holding lock: [ 180.588729] 000000007ba31468 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40e/0xc20 [ 180.596447] [ 180.596447] which lock already depends on the new lock. [ 180.596447] [ 180.604743] [ 180.604743] the existing dependency chain (in reverse order) is: [ 180.612348] [ 180.612348] -> #2 (rtnl_mutex){+.+.}: [ 180.617621] __mutex_lock+0x166/0x1710 [ 180.622008] mutex_lock_nested+0x16/0x20 [ 180.626676] rtnl_lock+0x17/0x20 [ 180.630594] bond_netdev_notify_work+0x44/0xd0 [ 180.635682] process_one_work+0xc90/0x1b90 [ 180.640415] worker_thread+0x17f/0x1390 [ 180.644889] kthread+0x35a/0x420 [ 180.648755] ret_from_fork+0x3a/0x50 [ 180.652969] [ 180.652969] -> #1 ((work_completion)(&(&nnw->work)->work)){+.+.}: [ 180.660677] process_one_work+0xc0a/0x1b90 [ 180.665415] worker_thread+0x17f/0x1390 [ 180.669897] kthread+0x35a/0x420 [ 180.673776] ret_from_fork+0x3a/0x50 [ 180.677989] [ 180.677989] -> #0 ((wq_completion)bond_dev->name){+.+.}: [ 180.684913] lock_acquire+0x1ed/0x520 [ 180.689223] flush_workqueue+0x30a/0x1e10 [ 180.693926] drain_workqueue+0x2a9/0x640 [ 180.698558] destroy_workqueue+0xc6/0x9c0 [ 180.703211] __alloc_workqueue_key+0xed8/0x1170 [ 180.708386] bond_init+0x274/0x970 [ 180.712471] register_netdevice+0x332/0x10f0 [ 180.717387] bond_newlink+0x49/0xa0 [ 180.721516] rtnl_newlink+0xec6/0x1d40 [ 180.725902] rtnetlink_rcv_msg+0x46a/0xc20 [ 180.730640] netlink_rcv_skb+0x172/0x440 [ 180.735256] rtnetlink_rcv+0x1c/0x20 [ 180.739477] netlink_unicast+0x5a5/0x760 [ 180.744041] netlink_sendmsg+0xa18/0xfc0 [ 180.748609] sock_sendmsg+0xd5/0x120 [ 180.752831] ___sys_sendmsg+0x7fd/0x930 [ 180.757481] __sys_sendmsg+0x11d/0x280 [ 180.761874] __x64_sys_sendmsg+0x78/0xb0 [ 180.766445] do_syscall_64+0x1b9/0x820 [ 180.770848] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 180.776533] [ 180.776533] other info that might help us debug this: [ 180.776533] [ 180.784652] Chain exists of: [ 180.784652] (wq_completion)bond_dev->name --> (work_completion)(&(&nnw->work)->work) --> rtnl_mutex [ 180.784652] [ 180.798403] Possible unsafe locking scenario: [ 180.798403] [ 180.804444] CPU0 CPU1 [ 180.809086] ---- ---- [ 180.813728] lock(rtnl_mutex); [ 180.816993] lock((work_completion)(&(&nnw->work)->work)); [ 180.825260] lock(rtnl_mutex); [ 180.831156] lock((wq_completion)bond_dev->name); [ 180.836066] [ 180.836066] *** DEADLOCK *** [ 180.836066] [ 180.842111] 1 lock held by syz-executor0/5781: [ 180.846671] #0: 000000007ba31468 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x40e/0xc20 [ 180.854812] [ 180.854812] stack backtrace: [ 180.859417] CPU: 1 PID: 5781 Comm: syz-executor0 Not tainted 4.19.0-rc3+ #10 [ 180.866592] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 180.875926] Call Trace: [ 180.878498] dump_stack+0x1c4/0x2b4 [ 180.882107] ? dump_stack_print_info.cold.2+0x52/0x52 [ 180.887285] ? vprintk_func+0x85/0x181 [ 180.891160] print_circular_bug.isra.33.cold.54+0x1bd/0x27d [ 180.896849] ? save_trace+0xe0/0x290 [ 180.900547] __lock_acquire+0x33e4/0x4ec0 [ 180.904677] ? mark_held_locks+0x130/0x130 [ 180.908913] ? select_idle_sibling+0x986/0xe80 [ 180.913823] ? __lock_is_held+0xb5/0x140 [ 180.917875] ? select_task_rq_fair+0x754/0x34f0 [ 180.922527] lock_acquire+0x1ed/0x520 [ 180.926313] ? flush_workqueue+0x2db/0x1e10 [ 180.930618] ? lock_release+0x970/0x970 [ 180.934571] ? lockdep_init_map+0x9/0x10 [ 180.938672] ? __init_waitqueue_head+0x9e/0x150 [ 180.943328] ? init_wait_entry+0x1c0/0x1c0 [ 180.947548] ? __lock_is_held+0xb5/0x140 [ 180.951597] flush_workqueue+0x30a/0x1e10 [ 180.955728] ? flush_workqueue+0x2db/0x1e10 [ 180.960029] ? lock_acquire+0x1ed/0x520 [ 180.963986] ? drain_workqueue+0xa9/0x640 [ 180.968133] ? lock_release+0x970/0x970 [ 180.972092] ? task_change_group_fair+0xa30/0xa30 [ 180.977005] ? flush_rcu_work+0x90/0x90 [ 180.980972] ? graph_lock+0x170/0x170 [ 180.984757] ? __mutex_lock+0x872/0x1710 [ 180.988808] ? drain_workqueue+0xa9/0x640 [ 180.992998] ? graph_lock+0x170/0x170 [ 180.996793] ? find_held_lock+0x36/0x1c0 [ 181.000843] ? drain_workqueue+0x13f/0x640 [ 181.005058] ? lock_downgrade+0x900/0x900 [ 181.009187] ? graph_lock+0x170/0x170 [ 181.012973] ? find_held_lock+0x36/0x1c0 [ 181.017069] ? kasan_check_write+0x14/0x20 [ 181.021304] ? __mutex_unlock_slowpath+0x197/0x8c0 [ 181.026225] ? wait_for_completion+0x8a0/0x8a0 [ 181.030963] ? do_raw_spin_unlock+0xa7/0x2f0 [ 181.035359] drain_workqueue+0x2a9/0x640 [ 181.039401] ? drain_workqueue+0x2a9/0x640 [ 181.043661] ? flush_workqueue+0x1e10/0x1e10 [ 181.048097] ? save_stack+0xa9/0xd0 [ 181.051714] ? save_stack+0x43/0xd0 [ 181.055324] ? __kasan_slab_free+0x102/0x150 [ 181.059778] ? kasan_slab_free+0xe/0x10 [ 181.063743] ? kfree+0xcf/0x230 [ 181.067012] ? print_usage_bug+0xc0/0xc0 [ 181.071069] ? register_netdevice+0x332/0x10f0 [ 181.075647] ? bond_newlink+0x49/0xa0 [ 181.079441] ? rtnl_newlink+0xec6/0x1d40 [ 181.083489] ? rtnetlink_rcv_msg+0x46a/0xc20 [ 181.087885] ? netlink_rcv_skb+0x172/0x440 [ 181.092107] ? rtnetlink_rcv+0x1c/0x20 [ 181.095983] ? netlink_unicast+0x5a5/0x760 [ 181.100205] ? netlink_sendmsg+0xa18/0xfc0 [ 181.104429] ? sock_sendmsg+0xd5/0x120 [ 181.108308] destroy_workqueue+0xc6/0x9c0 [ 181.112449] ? kasan_check_write+0x14/0x20 [ 181.116683] ? wq_watchdog_timer_fn+0x810/0x810 [ 181.121342] ? mark_held_locks+0xc7/0x130 [ 181.125476] ? kfree+0x107/0x230 [ 181.128832] ? kfree+0x107/0x230 [ 181.132272] ? lockdep_hardirqs_on+0x421/0x5c0 [ 181.136845] ? trace_hardirqs_on+0xbd/0x310 [ 181.141155] ? init_rescuer.part.25+0x155/0x190 [ 181.145819] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 181.151260] ? __kasan_slab_free+0x119/0x150 [ 181.155663] ? init_rescuer.part.25+0x155/0x190 [ 181.160331] __alloc_workqueue_key+0xed8/0x1170 [ 181.165004] ? workqueue_sysfs_register+0x3f0/0x3f0 [ 181.170011] ? put_dec+0xf0/0xf0 [ 181.173363] ? format_decode+0x1b2/0xaf0 [ 181.177434] ? set_precision+0xe0/0xe0 [ 181.181315] ? simple_strtoll+0xa0/0xa0 [ 181.185309] ? graph_lock+0x170/0x170 [ 181.189125] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 181.194657] ? find_held_lock+0x36/0x1c0 [ 181.198711] ? lock_downgrade+0x900/0x900 [ 181.202871] ? check_preemption_disabled+0x48/0x200 [ 181.207881] ? rcu_read_unlock_special.part.39+0x11f0/0x11f0 [ 181.213674] ? kasan_check_read+0x11/0x20 [ 181.217811] ? rcu_dynticks_curr_cpu_in_eqs+0x9f/0x160 [ 181.223078] ? rcu_bh_qs+0xc0/0xc0 [ 181.226611] bond_init+0x274/0x970 [ 181.230142] ? __dev_get_by_name+0x170/0x170 [ 181.234540] ? bond_set_rx_mode+0x560/0x560 [ 181.238854] ? rtnl_is_locked+0xb5/0xf0 [ 181.242819] ? bond_set_rx_mode+0x560/0x560 [ 181.247129] register_netdevice+0x332/0x10f0 [ 181.251527] ? netdev_change_features+0x110/0x110 [ 181.256362] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 181.261892] ? ns_capable_common+0x13f/0x170 [ 181.266315] bond_newlink+0x49/0xa0 [ 181.269938] ? bond_changelink+0x2370/0x2370 [ 181.274333] rtnl_newlink+0xec6/0x1d40 [ 181.278213] ? rtnl_link_unregister+0x390/0x390 [ 181.282872] ? print_usage_bug+0xc0/0xc0 [ 181.286925] ? __lock_acquire+0x7ec/0x4ec0 [ 181.291169] ? graph_lock+0x170/0x170 [ 181.294964] ? print_usage_bug+0xc0/0xc0 [ 181.299011] ? __lock_acquire+0x7ec/0x4ec0 [ 181.303234] ? print_usage_bug+0xc0/0xc0 [ 181.307280] ? mark_held_locks+0x130/0x130 [ 181.311500] ? find_held_lock+0x36/0x1c0 [ 181.315548] ? lock_acquire+0x1ed/0x520 [ 181.319511] ? rtnetlink_rcv_msg+0x40e/0xc20 [ 181.323916] ? lock_release+0x970/0x970 [ 181.327878] ? arch_local_save_flags+0x40/0x40 [ 181.332453] ? mutex_trylock+0x2b0/0x2b0 [ 181.336507] ? __lock_acquire+0x7ec/0x4ec0 [ 181.340732] ? is_bpf_text_address+0xd3/0x170 [ 181.345223] ? graph_lock+0x170/0x170 [ 181.349028] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 181.354556] ? rtnl_get_link+0x170/0x370 [ 181.358612] ? rtnl_dump_all+0x600/0x600 [ 181.362679] ? kasan_check_read+0x11/0x20 [ 181.366822] ? rcu_dynticks_curr_cpu_in_eqs+0x9f/0x160 [ 181.372092] ? ns_capable_common+0x13f/0x170 [ 181.376497] ? rtnl_link_unregister+0x390/0x390 [ 181.381161] rtnetlink_rcv_msg+0x46a/0xc20 [ 181.385393] ? rtnetlink_put_metrics+0x690/0x690 [ 181.390156] netlink_rcv_skb+0x172/0x440 [ 181.394226] ? rtnetlink_put_metrics+0x690/0x690 [ 181.398981] ? netlink_ack+0xb80/0xb80 [ 181.402880] rtnetlink_rcv+0x1c/0x20 [ 181.406588] netlink_unicast+0x5a5/0x760 [ 181.410647] ? netlink_attachskb+0x9a0/0x9a0 [ 181.415055] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 181.420606] netlink_sendmsg+0xa18/0xfc0 [ 181.424668] ? netlink_unicast+0x760/0x760 [ 181.428909] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 181.434442] ? security_socket_sendmsg+0x94/0xc0 [ 181.439194] ? netlink_unicast+0x760/0x760 [ 181.443423] sock_sendmsg+0xd5/0x120 [ 181.447134] ___sys_sendmsg+0x7fd/0x930 [ 181.451124] ? copy_msghdr_from_user+0x580/0x580 [ 181.455975] ? check_preemption_disabled+0x48/0x200 [ 181.460989] ? __fget_light+0x2e9/0x430 [ 181.464954] ? fget_raw+0x20/0x20 [ 181.468397] ? __fget_light+0x2e9/0x430 [ 181.472361] ? fget_raw+0x20/0x20 [ 181.475806] ? __fd_install+0x2f9/0x8f0 [ 181.479783] ? get_unused_fd_flags+0x1a0/0x1a0 [ 181.484366] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 181.489941] ? sockfd_lookup_light+0xc5/0x160 [ 181.494462] __sys_sendmsg+0x11d/0x280 [ 181.498347] ? __ia32_sys_shutdown+0x80/0x80 [ 181.502750] ? __fdget_raw+0x20/0x20 [ 181.506482] ? __x64_sys_futex+0x47f/0x6a0 [ 181.510719] ? do_syscall_64+0x9a/0x820 [ 181.514698] ? do_syscall_64+0x9a/0x820 [ 181.518681] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 181.524132] ? trace_hardirqs_off+0xb8/0x310 [ 181.528564] __x64_sys_sendmsg+0x78/0xb0 [ 181.532636] do_syscall_64+0x1b9/0x820 [ 181.536519] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 181.541883] ? syscall_return_slowpath+0x5e0/0x5e0 [ 181.546826] ? trace_hardirqs_on_caller+0x310/0x310 [ 181.551863] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 181.556886] ? recalc_sigpending_tsk+0x180/0x180 [ 181.561634] ? kasan_check_write+0x14/0x20 [ 181.565887] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 181.570732] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 181.575942] RIP: 0033:0x4572a9 [ 181.579127] Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00