INFO: task syz-executor.0:27717 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D23064 27717 10146 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 netdev_run_todo+0x4d4/0x7d0 net/core/dev.c:9638 rtnl_unlock net/core/rtnetlink.c:112 [inline] rtnetlink_rcv_msg+0x46a/0xaf0 net/core/rtnetlink.c:5437 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2478 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5454 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: Bad RIP value. RSP: 002b:00007f5ad9991c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f5ad99926d4 RCX: 000000000045c449 RDX: 0000000000000000 RSI: 0000000020000080 RDI: 0000000000000008 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009f9 R14: 00000000004cc6fa R15: 000000000076bf2c INFO: task syz-executor.5:28566 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28360 28566 10164 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 sock_do_ioctl+0x24e/0x2f0 net/socket.c:1066 sock_ioctl+0x3ed/0x790 net/socket.c:1204 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: Bad RIP value. RSP: 002b:00007f8dd3f69c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f8dd3f6a6d4 RCX: 000000000045c449 RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000005 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000040e R14: 00000000004c66d9 R15: 000000000076bf2c Showing all locks held in the system: 3 locks held by kworker/0:0/5: #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff888215503528 ((wq_completion)ipv6_addrconf){+.+.}, at: process_one_work+0x8dd/0x17a0 kernel/workqueue.c:2235 #1: ffffc90000cbfdc0 ((addr_chk_work).work){+.+.}, at: process_one_work+0x917/0x17a0 kernel/workqueue.c:2239 #2: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 4 locks held by kworker/u4:1/21: #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880a9a85928 ((wq_completion)netns){+.+.}, at: process_one_work+0x8dd/0x17a0 kernel/workqueue.c:2235 #1: ffffc90000dd7dc0 (net_cleanup_work){+.+.}, at: process_one_work+0x917/0x17a0 kernel/workqueue.c:2239 #2: ffffffff8a7420c8 (pernet_ops_rwsem){++++}, at: cleanup_net+0xa1/0xb10 net/core/net_namespace.c:551 #3: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 2 locks held by kworker/u4:8/680: 1 lock held by khungtaskd/1089: #0: ffffffff89bac280 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5333 1 lock held by rsyslogd/10013: #0: ffff8880a6c67660 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:821 2 locks held by getty/10103: #0: ffff8880a72f1090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000642b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10104: #0: ffff8880a8ea8090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900063db2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10105: #0: ffff88809a1db090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000647b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10106: #0: ffff8880a2d84090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000643b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10107: #0: ffff88809a1dc090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000645b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10108: #0: ffff88809a65b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000646b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10109: #0: ffff888094aba090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900063ab2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.0/12616: #0: ffff8880925e2740 (&sb->s_type->i_mutex_key#12){+.+.}, at: inode_lock include/linux/fs.h:791 [inline] #0: ffff8880925e2740 (&sb->s_type->i_mutex_key#12){+.+.}, at: __sock_release+0x89/0x280 net/socket.c:604 #1: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 2 locks held by syz-executor.5/10189: #0: ffff8880924c1240 (&sb->s_type->i_mutex_key#12){+.+.}, at: inode_lock include/linux/fs.h:791 [inline] #0: ffff8880924c1240 (&sb->s_type->i_mutex_key#12){+.+.}, at: __sock_release+0x89/0x280 net/socket.c:604 #1: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.0/27717: #0: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 2 locks held by syz-executor.4/28250: 1 lock held by syz-executor.5/28566: #0: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/0:2/28562: #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa426d28 ((wq_completion)events){+.+.}, at: process_one_work+0x8dd/0x17a0 kernel/workqueue.c:2235 #1: ffffc90007747dc0 ((linkwatch_work).work){+.+.}, at: process_one_work+0x917/0x17a0 kernel/workqueue.c:2239 #2: ffffffff8a74dd80 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1089 Comm: khungtaskd Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xb11/0x10c0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 28250 Comm: syz-executor.4 Not tainted 5.6.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:apic_timer_interrupt+0x0/0x20 arch/x86/entry/entry_64.S:829 Code: 31 ff fc e8 37 53 00 f9 48 89 e7 e8 aa 96 00 f9 e8 0e 53 00 f9 e9 c5 f2 ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <68> 13 ff ff ff e8 76 f1 ff ff e8 61 2e 00 00 e9 6b f2 ff ff 66 90 RSP: 0018:ffffc90000da8c88 EFLAGS: 00000087 RAX: 00000000d66fc000 RBX: ffff8880ae934bc0 RCX: 1ffffffff12f962d RDX: 00000000387eb37e RSI: ffffffff83a000d3 RDI: ffff8880ae934bcc RBP: ffffc90000da8cd8 R08: ffff88809fed8080 R09: fffffbfff16a3586 R10: fffffbfff16a3585 R11: ffffffff8b51ac2f R12: 000000003a4088b9 R13: 00000000e1282a53 R14: 0000000000000000 R15: dffffc0000000000 FS: 00007f031a50e700(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000045c41f CR3: 0000000045d4e000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: prandom_u32+0x57/0xb0 lib/random32.c:84 garp_join_timer_arm+0x26/0x80 net/802/garp.c:397 garp_join_timer+0x73/0x80 net/802/garp.c:411 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers kernel/time/timer.c:1773 [inline] __run_timers kernel/time/timer.c:1740 [inline] run_timer_softirq+0x6c3/0x1790 kernel/time/timer.c:1786 __do_softirq+0x262/0x98c kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2148 [inline] nf_ct_iterate_cleanup+0x212/0x4e0 net/netfilter/nf_conntrack_core.c:2171 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2256 [inline] nf_ct_iterate_cleanup_net+0x133/0x190 net/netfilter/nf_conntrack_core.c:2241 masq_device_event+0xb5/0xe0 net/netfilter/nf_nat_masquerade.c:88 notifier_call_chain+0xc2/0x230 kernel/notifier.c:83 __raw_notifier_call_chain kernel/notifier.c:361 [inline] raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:368 call_netdevice_notifiers_info net/core/dev.c:1948 [inline] call_netdevice_notifiers_info+0xba/0x130 net/core/dev.c:1933 call_netdevice_notifiers_extack net/core/dev.c:1960 [inline] call_netdevice_notifiers net/core/dev.c:1974 [inline] __dev_notify_flags+0x1e9/0x2c0 net/core/dev.c:8181 dev_change_flags+0x10d/0x170 net/core/dev.c:8217 do_setlink+0xa47/0x3720 net/core/rtnetlink.c:2596 rtnl_group_changelink net/core/rtnetlink.c:3103 [inline] __rtnl_newlink+0xdd1/0x1790 net/core/rtnetlink.c:3257 rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3377 rtnetlink_rcv_msg+0x45e/0xaf0 net/core/rtnetlink.c:5436 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2478 rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5454 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 ____sys_sendmsg+0x753/0x880 net/socket.c:2343 ___sys_sendmsg+0x100/0x170 net/socket.c:2397 __sys_sendmsg+0x105/0x1d0 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2437 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f031a50dc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f031a50e6d4 RCX: 000000000045c449 RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009f9 R14: 00000000004cc6fa R15: 000000000076bf2c INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 0.000 msecs