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INFO: task hung in cleanup_net

Status: fixed on 2018/01/03 02:35
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+b17f10c8a8c693b40723d40d6553fbc54d197679@syzkaller.appspotmail.com
Fix commit: 21b594435005 net: Fix double free and memory corruption in get_net_ns_by_id()
First crash: 2325d, last: 2325d
▶ ▼ Similar bugs (11)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cleanup_net (2) net 2 1821d 1821d 0/26 closed as invalid on 2019/05/08 13:05
android-44 INFO: task hung in cleanup_net 10 1775d 1817d 0/2 auto-closed as invalid on 2019/10/25 08:38
linux-4.19 INFO: task hung in cleanup_net 1 1440d 1440d 0/1 auto-closed as invalid on 2020/09/08 00:00
linux-4.14 INFO: task hung in cleanup_net C inconclusive 23 828d 1833d 0/1 upstream: reported C repro on 2019/04/13 10:16
upstream INFO: task hung in cleanup_net (3) net 1 1755d 1755d 0/26 auto-closed as invalid on 2019/10/25 14:21
android-49 INFO: task hung in cleanup_net 4 1825d 1832d 0/3 auto-closed as invalid on 2019/10/18 21:44
upstream INFO: task hung in cleanup_net (4) net 2 1339d 1344d 0/26 auto-closed as invalid on 2020/11/17 15:39
android-414 INFO: task hung in cleanup_net C 45 1693d 1836d 0/1 public: reported C repro on 2019/04/11 00:00
android-49 INFO: task hung in cleanup_net (2) 1 1609d 1609d 0/3 auto-closed as invalid on 2020/03/23 02:35
upstream INFO: task hung in cleanup_net (6) net 1 293d 293d 0/26 auto-obsoleted due to no activity on 2023/09/30 00:07
upstream INFO: task hung in cleanup_net (5) net 3 1066d 1111d 0/26 auto-closed as invalid on 2021/09/03 11:33

Sample crash report:
sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512
sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512
sctp: sctp_transport_update_pmtu: Reported pmtu 508 too low, using default minimum of 512
INFO: task kworker/u4:11:3785 blocked for more than 120 seconds.
      Not tainted 4.15.0-rc2-next-20171207+ #61
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:11   D16448  3785      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 context_switch kernel/sched/core.c:2800 [inline]
 __schedule+0x8eb/0x2060 kernel/sched/core.c:3376
 schedule+0xf5/0x430 kernel/sched/core.c:3435
 schedule_preempt_disabled+0x10/0x20 kernel/sched/core.c:3493
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0xaad/0x1a80 kernel/locking/mutex.c:893
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
 cleanup_net+0x24c/0xb60 net/core/net_namespace.c:453
 process_one_work+0xbfd/0x1bc0 kernel/workqueue.c:2113
 worker_thread+0x223/0x1990 kernel/workqueue.c:2247
 kthread+0x37a/0x440 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524

Showing all locks held in the system:
2 locks held by khungtaskd/672:
 #0:  (rcu_read_lock){....}, at: [<00000000b9bef8ab>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
 #0:  (rcu_read_lock){....}, at: [<00000000b9bef8ab>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249
 #1:  (tasklist_lock){.+.+}, at: [<000000006d6acf8b>] debug_show_all_locks+0xd3/0x400 kernel/locking/lockdep.c:4554
1 lock held by rsyslogd/2970:
 #0:  (&f->f_pos_lock){+.+.}, at: [<000000001cede688>] __fdget_pos+0x131/0x1a0 fs/file.c:765
2 locks held by getty/3052:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
2 locks held by getty/3053:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
2 locks held by getty/3054:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
2 locks held by getty/3055:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
2 locks held by getty/3056:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
2 locks held by getty/3057:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
2 locks held by getty/3058:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000004e0245ba>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000ff863b18>] n_tty_read+0x2f2/0x1a10 drivers/tty/n_tty.c:2131
1 lock held by syz-executor2/3320:
 #0:  (rtnl_mutex){+.+.}, at: [<0000000063c47ced>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
4 locks held by kworker/u4:11/3785:
 #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<0000000087d81703>] __write_once_size include/linux/compiler.h:212 [inline]
 #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<0000000087d81703>] atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<0000000087d81703>] atomic_long_set include/asm-generic/atomic-long.h:57 [inline]
 #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<0000000087d81703>] set_work_data kernel/workqueue.c:619 [inline]
 #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<0000000087d81703>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<0000000087d81703>] process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084
 #1:  (net_cleanup_work){+.+.}, at: [<000000008a817b5c>] process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088
 #2:  (net_mutex){+.+.}, at: [<0000000079150fd8>] cleanup_net+0x247/0xb60 net/core/net_namespace.c:450
 #3:  (rtnl_mutex){+.+.}, at: [<0000000063c47ced>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
3 locks held by kworker/0:6/14978:
 #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<0000000087d81703>] __write_once_size include/linux/compiler.h:212 [inline]
 #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<0000000087d81703>] atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<0000000087d81703>] atomic_long_set include/asm-generic/atomic-long.h:57 [inline]
 #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<0000000087d81703>] set_work_data kernel/workqueue.c:619 [inline]
 #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<0000000087d81703>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline]
 #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: [<0000000087d81703>] process_one_work+0xad4/0x1bc0 kernel/workqueue.c:2084
 #1:  ((addr_chk_work).work){+.+.}, at: [<000000008a817b5c>] process_one_work+0xb2f/0x1bc0 kernel/workqueue.c:2088
 #2:  (rtnl_mutex){+.+.}, at: [<0000000063c47ced>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
1 lock held by syz-executor2/15852:
 #0:  (rtnl_mutex){+.+.}, at: [<0000000063c47ced>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
1 lock held by syz-executor7/15958:
 #0:  (rtnl_mutex){+.+.}, at: [<0000000063c47ced>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
1 lock held by syz-executor7/15961:
 #0:  (rtnl_mutex){+.+.}, at: [<0000000063c47ced>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 672 Comm: khungtaskd Not tainted 4.15.0-rc2-next-20171207+ #61
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103
 nmi_trigger_cpumask_backtrace+0x122/0x180 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:138 [inline]
 check_hung_task kernel/hung_task.c:132 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline]
 watchdog+0x90c/0xd60 kernel/hung_task.c:249
 kthread+0x37a/0x440 kernel/kthread.c:238
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:524
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 15938 Comm: syz-executor7 Not tainted 4.15.0-rc2-next-20171207+ #61
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:inb arch/x86/include/asm/io.h:348 [inline]
RIP: 0010:io_serial_in+0x6b/0x90 drivers/tty/serial/8250/8250_port.c:434
RSP: 0018:ffff8801c1c173e8 EFLAGS: 00000002
RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: ffffc90001c88000 RDI: ffffffff880fa9c0
RBP: ffff8801c1c173f8 R08: 0000000000000002 R09: 000000000000000c
R10: 0000000000000000 R11: ffffffff87896d20 R12: ffffffff880fa980
R13: 0000000000000020 R14: fffffbfff101f577 R15: fffffbfff101f53a
FS:  00007f1ef8fad700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbea91b6000 CR3: 00000001d0aaa000 CR4: 00000000001406f0
DR0: 0000000020001000 DR1: 0000000020001000 DR2: 0000000020001020
DR3: 0000000020000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 serial_in drivers/tty/serial/8250/8250.h:111 [inline]
 wait_for_xmitr+0x93/0x1e0 drivers/tty/serial/8250/8250_port.c:2033
 serial8250_console_putchar+0x1f/0x60 drivers/tty/serial/8250/8250_port.c:3170
 uart_console_write+0xac/0xe0 drivers/tty/serial/serial_core.c:1858
 serial8250_console_write+0x647/0xa20 drivers/tty/serial/8250/8250_port.c:3236
 univ8250_console_write+0x5f/0x70 drivers/tty/serial/8250/8250_core.c:590
 call_console_drivers kernel/printk/printk.c:1574 [inline]
 console_unlock+0x788/0xd70 kernel/printk/printk.c:2233
 vprintk_emit+0x4ad/0x590 kernel/printk/printk.c:1757
 vprintk_default+0x28/0x30 kernel/printk/printk.c:1796
 vprintk_func+0x57/0xc0 kernel/printk/printk_safe.c:379
 printk+0xaa/0xca kernel/printk/printk.c:1829
 __dev_set_promiscuity+0x2a4/0x630 net/core/dev.c:6609
 __dev_change_flags+0x559/0x990 net/core/dev.c:6826
 dev_change_flags+0x88/0x140 net/core/dev.c:6886
 dev_ifsioc+0x60d/0x9b0 net/core/dev_ioctl.c:257
 dev_ioctl+0x2c2/0xf90 net/core/dev_ioctl.c:566
 sock_do_ioctl+0x94/0xb0 net/socket.c:971
 sock_ioctl+0x2c2/0x440 net/socket.c:1061
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1530 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 entry_SYSCALL_64_fastpath+0x1f/0x96
RIP: 0033:0x452a39
RSP: 002b:00007f1ef8facc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1ef8fad700 RCX: 0000000000452a39
RDX: 00000000208a3fe0 RSI: 0000000000008914 RDI: 0000000000000019
RBP: 0000000000a6f880 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000
R13: 0000000000a6f7ff R14: 00007f1ef8fad9c0 R15: 0000000000000002
Code: 24 d9 00 00 00 49 8d 7c 24 40 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 d3 e3 80 3c 02 00 75 17 41 03 5c 24 40 89 da ec <5b> 0f b6 c0 41 5c 5d c3 e8 88 ad 18 ff eb c2 e8 e1 ad 18 ff eb

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2017/12/07 08:15 linux-next e40fd8d6b4d9 5d643f8e .config console log report ci-upstream-next-kasan-gce
* Struck through repros no longer work on HEAD.