syzbot


INFO: task hung in cleanup_net

Status: auto-closed as invalid on 2020/09/08 00:00
Reported-by: syzbot+7edaa13e19c00a55aee5@syzkaller.appspotmail.com
First crash: 827d, last: 827d
similar bugs (10):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in cleanup_net (2) 2 1208d 1209d 0/23 closed as invalid on 2019/05/08 13:05
android-44 INFO: task hung in cleanup_net 10 1162d 1204d 0/2 auto-closed as invalid on 2019/10/25 08:38
upstream INFO: task hung in cleanup_net 1 1713d 1701d 3/23 fixed on 2018/01/03 02:35
linux-4.14 INFO: task hung in cleanup_net C inconclusive 23 215d 1221d 0/1 upstream: reported C repro on 2019/04/13 10:16
upstream INFO: task hung in cleanup_net (3) 1 1143d 1143d 0/23 auto-closed as invalid on 2019/10/25 14:21
android-49 INFO: task hung in cleanup_net 4 1212d 1220d 0/3 auto-closed as invalid on 2019/10/18 21:44
upstream INFO: task hung in cleanup_net (4) 2 727d 731d 0/23 auto-closed as invalid on 2020/11/17 15:39
android-414 INFO: task hung in cleanup_net C 45 1081d 1223d 0/1 public: reported C repro on 2019/04/11 00:00
android-49 INFO: task hung in cleanup_net (2) 1 996d 996d 0/3 auto-closed as invalid on 2020/03/23 02:35
upstream INFO: task hung in cleanup_net (5) 3 453d 499d 0/23 auto-closed as invalid on 2021/09/03 11:33

Sample crash report:
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.4'.
netlink: 4 bytes leftover after parsing attributes in process `syz-executor.4'.
IPVS: ftp: loaded support on port[0] = 21
INFO: task kworker/u4:1:19422 blocked for more than 140 seconds.
      Not tainted 4.19.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:1    D25872 19422      2 0x80000000
Workqueue: netns cleanup_net
Call Trace:
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x21b/0x3c0 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:83 [inline]
 down_read+0x45/0xb0 kernel/locking/rwsem.c:26
 cleanup_net+0xa8/0x850 net/core/net_namespace.c:520
 process_one_work+0x91f/0x1640 kernel/workqueue.c:2155
 worker_thread+0x96/0xe20 kernel/workqueue.c:2298
 kthread+0x34a/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
INFO: task syz-executor.0:958 blocked for more than 140 seconds.
      Not tainted 4.19.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28416   958   6436 0x00000004
Call Trace:
 schedule+0x8d/0x1b0 kernel/sched/core.c:3559
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x4f/0x90 kernel/locking/rwsem.c:72
 unregister_netdevice_notifier+0x75/0x320 net/core/dev.c:1712
 raw_release+0x53/0x6c0 net/can/raw.c:358
 __sock_release+0xcd/0x2a0 net/socket.c:579
 sock_close+0x15/0x20 net/socket.c:1140
 __fput+0x2cd/0x890 fs/file_table.c:278
 task_work_run+0x13f/0x1b0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x25a/0x2b0 arch/x86/entry/common.c:167
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x416421
Code: Bad RIP value.
RSP: 002b:00007ffe499eddd0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 0000000000416421
RDX: 0000000000000000 RSI: 0000000000000081 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000791558 R09: 0000000000000000
R10: 00007ffe499edeb0 R11: 0000000000000293 R12: 0000000000791560
R13: 0000000000000000 R14: ffffffffffffffff R15: 000000000078bf0c

Showing all locks held in the system:
1 lock held by khungtaskd/1079:
 #0: 0000000012542bb0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by systemd-journal/3678:
2 locks held by syz-fuzzer/6416:
2 locks held by kworker/u4:0/26425:
3 locks held by kworker/1:1/27902:
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 000000004e6be00a ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x81a/0x1640 kernel/workqueue.c:2126
 #1: 00000000cdc2fc4f ((addr_chk_work).work){+.+.}, at: process_one_work+0x84e/0x1640 kernel/workqueue.c:2130
 #2: 000000002808175e (rtnl_mutex){+.+.}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4475
3 locks held by kworker/u4:1/19422:
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: __write_once_size include/linux/compiler.h:220 [inline]
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:40 [inline]
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:59 [inline]
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: set_work_data kernel/workqueue.c:617 [inline]
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline]
 #0: 00000000c57d1346 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0x81a/0x1640 kernel/workqueue.c:2126
 #1: 00000000c9201e94 (net_cleanup_work){+.+.}, at: process_one_work+0x84e/0x1640 kernel/workqueue.c:2130
 #2: 0000000079866836 (pernet_ops_rwsem){++++}, at: cleanup_net+0xa8/0x850 net/core/net_namespace.c:520
1 lock held by syz-executor.5/20314:
1 lock held by syz-executor.5/30214:
2 locks held by syz-executor.0/958:
 #0: 0000000010554542 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline]
 #0: 0000000010554542 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:578
 #1: 0000000079866836 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x75/0x320 net/core/dev.c:1712
3 locks held by syz-executor.0/976:

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

NMI backtrace for cpu 1
CPU: 1 PID: 1079 Comm: khungtaskd Not tainted 4.19.122-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+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x962/0xe40 kernel/hung_task.c:287
 kthread+0x34a/0x420 kernel/kthread.c:246
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 976 Comm: syz-executor.0 Not tainted 4.19.122-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:match_held_lock+0x20/0x4f0 kernel/locking/lockdep.c:3476
Code: e9 1b ff ff ff 0f 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 41 56 41 55 41 54 55 53 48 89 fb 48 83 c7 10 48 89 fa 48 83 ec 08 <48> c1 ea 03 80 3c 02 00 0f 85 e2 03 00 00 48 39 73 10 0f 84 f9 01
RSP: 0000:ffff8880ae607d80 EFLAGS: 00000082
RAX: dffffc0000000000 RBX: ffff88804bfbcfc0 RCX: ffffffff81595beb
RDX: ffff88804bfbcfd0 RSI: ffff8880ae625b98 RDI: ffff88804bfbcfd0
RBP: ffff8880ae625b98 R08: ffff88804bfbc6c0 R09: ffffffff8ad01008
R10: ffffffff8ad01010 R11: 0000000000000001 R12: ffffed10097f79e8
R13: ffff88804bfbcf48 R14: ffff88804bfbcfc0 R15: 0000000000000003
FS:  00007f8b9ed90700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002262d7c8 CR3: 00000001f91b7000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __lock_is_held+0xad/0x140 kernel/locking/lockdep.c:3727
 lock_is_held_type+0x10d/0x210 kernel/locking/lockdep.c:3945
 lock_is_held include/linux/lockdep.h:344 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1369 [inline]
 __hrtimer_run_queues+0x4d6/0xd50 kernel/time/hrtimer.c:1463
 hrtimer_interrupt+0x312/0x770 kernel/time/hrtimer.c:1521
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1067 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1092
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:893
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:qlink_free mm/kasan/quarantine.c:150 [inline]
RIP: 0010:qlist_free_all+0xfc/0x140 mm/kasan/quarantine.c:166
Code: 50 08 48 8d 4a ff 83 e2 01 48 0f 45 c1 4c 8b 70 18 e9 40 ff ff ff e8 63 1a cf ff 48 83 3d 63 94 34 07 00 74 36 4c 89 ff 57 9d <0f> 1f 44 00 00 4d 85 e4 75 9e 49 c7 45 08 00 00 00 00 49 c7 45 00
RSP: 0000:ffff888203f875d0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000007 RBX: ffff88800e2a48c0 RCX: 1ffff110097f79f2
RDX: 0000000000000000 RSI: ffff88804bfbcf98 RDI: 0000000000000282
RBP: 0000000000000000 R08: ffff88804bfbc6c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88800e2a47e0
R13: ffff888203f87608 R14: ffff88812c2f7240 R15: 0000000000000282
 quarantine_reduce+0x164/0x1a0 mm/kasan/quarantine.c:259
 kasan_kmalloc+0x95/0xe0 mm/kasan/kasan.c:538
 __do_kmalloc mm/slab.c:3727 [inline]
 __kmalloc_track_caller+0x153/0x770 mm/slab.c:3742
 kstrdup+0x36/0x70 mm/util.c:56
 kstrdup_const+0x53/0x80 mm/util.c:77
 __kernfs_new_node+0x9b/0x680 fs/kernfs/dir.c:629
 kernfs_new_node+0x92/0x120 fs/kernfs/dir.c:693
 kernfs_create_dir_ns+0x48/0x150 fs/kernfs/dir.c:1019
 sysfs_create_dir_ns+0x127/0x280 fs/sysfs/dir.c:58
 create_dir lib/kobject.c:88 [inline]
 kobject_add_internal+0x29d/0x8c0 lib/kobject.c:247
 kobject_add_varg lib/kobject.c:382 [inline]
 kobject_init_and_add+0x101/0x160 lib/kobject.c:453
 netdev_queue_add_kobject net/core/net-sysfs.c:1481 [inline]
 netdev_queue_update_kobjects+0x11e/0x3c0 net/core/net-sysfs.c:1509
 register_queue_kobjects net/core/net-sysfs.c:1551 [inline]
 netdev_register_kobject+0x29b/0x3b0 net/core/net-sysfs.c:1769
 register_netdevice+0x7f7/0xf50 net/core/dev.c:8710
 register_netdev+0x2d/0x50 net/core/dev.c:8832
 loopback_net_init+0x73/0x160 drivers/net/loopback.c:218
 ops_init+0xaf/0x410 net/core/net_namespace.c:129
 setup_net+0x2c2/0x6f0 net/core/net_namespace.c:315
 copy_net_ns+0x1d9/0x331 net/core/net_namespace.c:438
 create_new_namespaces+0x3fb/0x7c0 kernel/nsproxy.c:107
 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206
 ksys_unshare+0x439/0x8d0 kernel/fork.c:2530
 __do_sys_unshare kernel/fork.c:2598 [inline]
 __se_sys_unshare kernel/fork.c:2596 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2596
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c829
Code: 0d b7 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f8b9ed8fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 0000000000509f60 RCX: 000000000045c829
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000040000000
RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000c4e R14: 00000000004ce7bd R15: 00007f8b9ed906d4

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-19 2020/05/10 23:59 linux-4.19.y 033c4ea49a4b 8742a2b9 .config log report