INFO: task syz-executor.2:2074 blocked for more than 143 seconds. Not tainted 5.8.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29104 2074 7040 0x00004004 Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4312 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 __pipe_lock fs/pipe.c:87 [inline] pipe_write+0x5bd/0x16c0 fs/pipe.c:580 call_write_iter include/linux/fs.h:1908 [inline] new_sync_write+0x422/0x650 fs/read_write.c:503 vfs_write+0x59d/0x6b0 fs/read_write.c:578 ksys_write+0x1ee/0x250 fs/read_write.c:631 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cba9 Code: Bad RIP value. RSP: 002b:00007f620a929c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000050f7e0 RCX: 000000000045cba9 RDX: 000000004240a2a0 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000d65 R14: 00000000004cfb49 R15: 00007f620a92a6d4 INFO: task syz-executor.2:2079 blocked for more than 143 seconds. Not tainted 5.8.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28200 2079 7040 0x00000004 Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4312 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10d0 kernel/locking/mutex.c:1103 __netlink_dump_start+0x16a/0x900 net/netlink/af_netlink.c:2317 netlink_dump_start include/linux/netlink.h:246 [inline] rtnetlink_rcv_msg+0x70f/0xad0 net/core/rtnetlink.c:5423 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2469 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 sock_no_sendpage+0xee/0x130 net/core/sock.c:2853 kernel_sendpage net/socket.c:3642 [inline] sock_sendpage+0xe5/0x140 net/socket.c:945 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:448 splice_from_pipe_feed fs/splice.c:502 [inline] __splice_from_pipe+0x3dc/0x830 fs/splice.c:626 splice_from_pipe fs/splice.c:661 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:834 do_splice_from fs/splice.c:846 [inline] do_splice+0xbcd/0x1820 fs/splice.c:1144 __do_sys_splice fs/splice.c:1419 [inline] __se_sys_splice fs/splice.c:1401 [inline] __x64_sys_splice+0x198/0x250 fs/splice.c:1401 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cba9 Code: Bad RIP value. RSP: 002b:00007f620a908c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 000000000050a820 RCX: 000000000045cba9 RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 000000000078bfa0 R08: 000000000004ffe0 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000c26 R14: 00000000004cf1be R15: 00007f620a9096d4 Showing all locks held in the system: 1 lock held by khungtaskd/1152: #0: ffffffff89bc11c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6505: #0: ffff8880a0cd1db0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 3 locks held by kworker/1:7/14915: #0: ffff88809a134138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88809a134138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88809a134138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88809a134138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88809a134138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88809a134138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90006277da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8a7b7fe8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4543 3 locks held by syz-executor.5/2077: 1 lock held by syz-executor.2/2074: #0: ffff888042aca468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:87 [inline] #0: ffff888042aca468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x5bd/0x16c0 fs/pipe.c:580 2 locks held by syz-executor.2/2079: #0: ffff888042aca468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:66 [inline] #0: ffff888042aca468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x5a/0x70 fs/pipe.c:74 #1: ffffffff8a7b7fe8 (rtnl_mutex){+.+.}-{3:3}, at: __netlink_dump_start+0x16a/0x900 net/netlink/af_netlink.c:2317 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1152 Comm: khungtaskd Not tainted 5.8.0-rc4-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2077 Comm: syz-executor.5 Not tainted 5.8.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:fib6_age+0x5d/0x160 net/ipv6/ip6_fib.c:2287 Code: 54 4c 8b 2d 05 fb bc 02 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 <84> d2 0f 85 c3 00 00 00 8b 5d 54 31 ff 81 e3 00 00 40 00 89 de e8 RSP: 0018:ffffc90001de6a88 EFLAGS: 00000202 RAX: 0000000000000007 RBX: ffffffff86e3e640 RCX: ffffc900140a6000 RDX: 0000000000000000 RSI: ffffffff86e3e651 RDI: ffff88804c65c654 RBP: ffff88804c65c600 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90001de6db0 R13: 0000000100048b79 R14: fffff520003bcd96 R15: fffff520003bcd94 FS: 00007f35bb9ae700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4338021ec8 CR3: 0000000032ad5000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: fib6_clean_node+0x2a1/0x570 net/ipv6/ip6_fib.c:2176 fib6_walk_continue+0x4aa/0x8e0 net/ipv6/ip6_fib.c:2101 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2149 fib6_clean_tree+0xdb/0x120 net/ipv6/ip6_fib.c:2229 __fib6_clean_all+0x120/0x290 net/ipv6/ip6_fib.c:2245 fib6_clean_all net/ipv6/ip6_fib.c:2256 [inline] fib6_run_gc+0x113/0x2d0 net/ipv6/ip6_fib.c:2319 ndisc_netdev_event+0xb2/0x350 net/ipv6/ndisc.c:1785 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2027 call_netdevice_notifiers_extack net/core/dev.c:2039 [inline] call_netdevice_notifiers+0x79/0xa0 net/core/dev.c:2053 do_setlink+0x753/0x35c0 net/core/rtnetlink.c:2600 rtnl_group_changelink net/core/rtnetlink.c:3123 [inline] __rtnl_newlink+0xdea/0x1730 net/core/rtnetlink.c:3277 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3397 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5460 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2469 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:672 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2352 ___sys_sendmsg+0xf3/0x170 net/socket.c:2406 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2439 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cba9 Code: Bad RIP value. RSP: 002b:00007f35bb9adc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000503d20 RCX: 000000000045cba9 RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003 RBP: 000000000078c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000a7a R14: 00000000004cd567 R15: 00007f35bb9ae6d4