syzbot


INFO: task hung in ip_mc_drop_socket (2)

Status: auto-closed as invalid on 2022/01/18 13:17
Subsystems: net
[Documentation on labels]
First crash: 1083d, last: 1081d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-44 INFO: task hung in ip_mc_drop_socket 1 2384d 2384d 0/2 auto-closed as invalid on 2019/02/22 12:39
upstream INFO: task hung in ip_mc_drop_socket net 1 2368d 2367d 0/28 auto-closed as invalid on 2019/02/22 10:26
linux-4.19 INFO: task hung in ip_mc_drop_socket 1 962d 962d 0/1 auto-closed as invalid on 2022/06/16 11:31
linux-4.19 INFO: task hung in ip_mc_drop_socket (2) 1 716d 716d 0/1 auto-obsoleted due to no activity on 2023/02/17 23:08

Sample crash report:
INFO: task syz-executor.1:18027 blocked for more than 143 seconds.
      Not tainted 5.15.0-rc5-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1  state:D stack:28152 pid:18027 ppid:  6550 flags:0x00000004
Call Trace:
 context_switch kernel/sched/core.c:4940 [inline]
 __schedule+0xb44/0x5960 kernel/sched/core.c:6287
 schedule+0xd3/0x270 kernel/sched/core.c:6366
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425
 __mutex_lock_common kernel/locking/mutex.c:669 [inline]
 __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729
 ip_mc_drop_socket+0x89/0x260 net/ipv4/igmp.c:2685
 inet_release+0x97/0x280 net/ipv4/af_inet.c:414
 __sock_release+0xcd/0x280 net/socket.c:649
 sock_close+0x18/0x20 net/socket.c:1314
 __fput+0x288/0x9f0 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc81958567b
RSP: 002b:00007ffe28d65720 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007fc81958567b
RDX: 00007fc8196db000 RSI: 0000000000000081 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007fc8196db000
R13: 00007ffe28d65840 R14: 00007fc8196d5f60 R15: 0000000000050cae

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8b981ee0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446
4 locks held by kworker/u4:3/158:
 #0: ffff888143d8a938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888143d8a938 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888143d8a938 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888143d8a938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888143d8a938 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888143d8a938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
 #1: ffffc900012dfdb0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
 #2: ffffffff8d0d5990 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:555
 #3: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1244
1 lock held by in:imklog/6247:
 #0: ffff8880781919f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
3 locks held by kworker/0:16/13811:
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888010c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
 #1: ffffc90004b47db0 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
 #2: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
3 locks held by kworker/1:15/14778:
 #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888010c65d38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
 #1: ffffc90002ddfdb0 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
 #2: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x83/0xe10 net/wireless/reg.c:2423
3 locks held by kworker/1:18/14782:
 #0: ffff888147919138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888147919138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888147919138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888147919138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888147919138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888147919138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268
 #1: ffffc90004307db0 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272
 #2: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4590
2 locks held by syz-executor.1/18027:
 #0: ffff888032016810 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:786 [inline]
 #0: ffff888032016810 (&sb->s_type->i_mutex_key#13){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:648
 #1: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: ip_mc_drop_socket+0x89/0x260 net/ipv4/igmp.c:2685
1 lock held by syz-executor.1/18129:
 #0: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d0e90e8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:295
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 16817 Comm: kworker/u4:17 Not tainted 5.15.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:kasan_check_range+0xe/0x180 mm/kasan/generic.c:188
Code: f5 00 00 00 e9 23 82 3b 02 0f 1f 00 48 89 f2 be f8 00 00 00 e9 13 82 3b 02 0f 1f 00 48 85 f6 0f 84 70 01 00 00 49 89 f9 41 54 <44> 0f b6 c2 49 01 f1 55 53 0f 82 18 01 00 00 48 b8 ff ff ff ff ff
RSP: 0018:ffffc90004e47a50 EFLAGS: 00000002
RAX: 0000000000000000 RBX: 0000000000000028 RCX: ffffffff815be2b2
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8fd0c9e0
RBP: 0000000000000004 R08: 0000000000000000 R09: ffffffff8fd0c9e0
R10: fffffbfff1fa1956 R11: 0000000000000000 R12: ffff88801aba4370
R13: ffff88801aba3900 R14: 0000000000000000 R15: c26b05bd6c2f421f
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0ca792000 CR3: 000000007b7cb000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 instrument_atomic_read include/linux/instrumented.h:71 [inline]
 test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
 hlock_class kernel/locking/lockdep.c:199 [inline]
 __lock_acquire+0xbc2/0x54a0 kernel/locking/lockdep.c:5012
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 rcu_lock_acquire include/linux/rcupdate.h:267 [inline]
 rcu_read_lock include/linux/rcupdate.h:687 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:410 [inline]
 batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:721
 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
----------------
Code disassembly (best guess):
   0:	f5                   	cmc
   1:	00 00                	add    %al,(%rax)
   3:	00 e9                	add    %ch,%cl
   5:	23 82 3b 02 0f 1f    	and    0x1f0f023b(%rdx),%eax
   b:	00 48 89             	add    %cl,-0x77(%rax)
   e:	f2 be f8 00 00 00    	repnz mov $0xf8,%esi
  14:	e9 13 82 3b 02       	jmpq   0x23b822c
  19:	0f 1f 00             	nopl   (%rax)
  1c:	48 85 f6             	test   %rsi,%rsi
  1f:	0f 84 70 01 00 00    	je     0x195
  25:	49 89 f9             	mov    %rdi,%r9
  28:	41 54                	push   %r12
* 2a:	44 0f b6 c2          	movzbl %dl,%r8d <-- trapping instruction
  2e:	49 01 f1             	add    %rsi,%r9
  31:	55                   	push   %rbp
  32:	53                   	push   %rbx
  33:	0f 82 18 01 00 00    	jb     0x151
  39:	48                   	rex.W
  3a:	b8 ff ff ff ff       	mov    $0xffffffff,%eax
  3f:	ff                   	.byte 0xff

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/10/20 04:02 net-next-old cb3dc8901ba4 466b7db1 .config console log report info ci-upstream-net-kasan-gce INFO: task hung in ip_mc_drop_socket
2021/10/18 16:27 net-next-old d40dfa0cebd8 0c5d9412 .config console log report info ci-upstream-net-kasan-gce INFO: task hung in ip_mc_drop_socket
2021/10/18 14:20 net-next-old d40dfa0cebd8 0c5d9412 .config console log report info ci-upstream-net-kasan-gce INFO: task hung in ip_mc_drop_socket
2021/10/18 13:41 net-next-old d40dfa0cebd8 0c5d9412 .config console log report info ci-upstream-net-kasan-gce INFO: task hung in ip_mc_drop_socket
2021/10/20 13:09 linux-next 51dba6e335ff 418a00eb .config console log report info ci-upstream-linux-next-kasan-gce-root INFO: task hung in ip_mc_drop_socket
* Struck through repros no longer work on HEAD.