BUG: soft lockup in sock_close

Status: upstream: reported C repro on 2024/03/27 04:09
Bug presence: origin:downstream
[Documentation on labels]
Reported-by: syzbot+590c02cc06f6cd2951e1@syzkaller.appspotmail.com
First crash: 854d, last: 17h35m
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (3)
Date Name Commit Repro Result
2024/03/27 android14-6.1 (ToT) eef3b6e52937 C [report] BUG: soft lockup in sock_close
2024/03/27 lts (merge base) 883d1a956208 C Didn't crash
2024/04/10 upstream (ToT) 2c71fdf02a95 C Didn't crash
▶ ▼ Similar bugs (14)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-10 BUG: soft lockup in sock_close 1 syz, C 191 11d 856d 0/2 upstream: reported C repro on 2024/03/25 07:28
linux-5.15 INFO: rcu detected stall in sock_close (3) origin:upstream 1 syz, C error 17 50d 800d 0/3 upstream: reported C repro on 2024/05/20 00:06
android-5-15 BUG: soft lockup in sock_close origin:downstream 1 syz, C done 383 75d 855d 0/2 upstream: reported C repro on 2024/03/26 23:21
upstream INFO: rcu detected stall in sock_close (5) prio:normal bpf sctp tipc 1 syz, C error 91 2d16h 378d 0/29 upstream: reported C repro on 2025/07/16 17:01
linux-6.1 BUG: soft lockup in sock_close origin:lts-only 1 syz, C inconclusive 8 39d 583d 0/3 upstream: reported C repro on 2024/12/23 18:51
linux-5.15 INFO: rcu detected stall in sock_close (2) 1 1 917d 917d 0/3 auto-obsoleted due to no activity on 2024/05/03 14:38
upstream INFO: rcu detected stall in sock_close (4) net 1 2 1007d 1044d 0/29 auto-obsoleted due to no activity on 2024/01/24 15:51
linux-6.1 INFO: rcu detected stall in sock_close (3) 1 1 807d 807d 0/3 auto-obsoleted due to no activity on 2024/08/21 03:02
linux-6.1 INFO: rcu detected stall in sock_close origin:upstream 1 syz, C done 1 1115d 1115d 3/3 fixed on 2023/09/23 10:26
linux-6.1 INFO: rcu detected stall in sock_close (2) 1 1 909d 909d 0/3 auto-obsoleted due to no activity on 2024/05/11 05:25
upstream INFO: rcu detected stall in sock_close (3) tipc 1 syz, C done done 5 1717d 2212d 0/29 closed as invalid on 2022/02/08 10:42
linux-5.15 INFO: rcu detected stall in sock_close 1 syz, C error 2 1095d 1149d 0/3 auto-obsoleted due to no activity on 2023/11/07 13:02
linux-6.6 INFO: rcu detected stall in sock_close (2) origin:upstream 1 syz 1 5d11h 75d 0/2 upstream: reported syz repro on 2026/05/15 05:06
linux-6.6 INFO: rcu detected stall in sock_close 1 syz error 2 255d 338d 0/2 auto-obsoleted due to no activity on 2026/02/24 12:42
▶ ▼ Last patch testing requests (10)
Created Duration User Patch Repo Result
2026/07/08 12:07 16m retest repro android14-6.1 log
2026/07/08 12:07 14m retest repro android14-6.1 log
2026/07/08 12:07 16m retest repro android14-6.1 log
2026/07/08 12:07 14m retest repro android14-6.1 log
2026/07/08 12:07 25m retest repro android14-6.1 log
2026/06/04 04:46 14m retest repro android14-6.1 log
2026/06/04 04:46 16m retest repro android14-6.1 log
2026/06/04 04:46 16m retest repro android14-6.1 log
2026/06/04 04:46 15m retest repro android14-6.1 log
2026/06/04 04:46 13m retest repro android14-6.1 log

Sample crash report:
RBP: 00007f20b7c33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f20b7e26038 R14: 00007f20b7e25fa0 R15: 00007ffe95670ed8
 </TASK>
watchdog: BUG: soft lockup - CPU#0 stuck for 225s! [syz.2.17:377]
Modules linked in:
CPU: 0 PID: 377 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
RIP: 0010:__raw_callee_save___pv_queued_spin_unlock+0x10/0x17
Code: 41 51 41 52 41 53 e8 db 09 00 00 41 5b 41 5a 41 59 41 58 5f 5e 5a 59 5d c3 90 55 48 89 e5 52 b8 01 00 00 00 31 d2 f0 0f b0 17 <3c> 01 75 03 5a 5d c3 56 0f b6 f0 e8 bc ff ff ff 5e 5a 5d c3 0f 1f
RSP: 0018:ffffc900016f69d0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: dffffc0000000000 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000099082e3a RDI: ffffc900016f6e34
RBP: ffffc900016f69d8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff520002ded30 R12: ffffc900016f6e20
R13: ffff888123509e80 R14: 0000000099082e3a R15: 0000000099082e3a
FS:  00007f20b89866c0(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20b79ffd58 CR3: 0000000112092000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pv_queued_spin_unlock arch/x86/include/asm/paravirt.h:596 [inline]
 queued_spin_unlock arch/x86/include/asm/qspinlock.h:57 [inline]
 do_raw_spin_unlock include/linux/spinlock.h:204 [inline]
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:166 [inline]
 _raw_spin_unlock_bh+0x41/0x60 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 tipc_skb_peek_port net/tipc/msg.h:1235 [inline]
 tipc_sk_rcv+0x3da/0x2c20 net/tipc/socket.c:2493
 tipc_node_xmit+0x36f/0xd80 net/tipc/node.c:1703
 tipc_node_xmit_skb+0xf7/0x150 net/tipc/node.c:1768
 tipc_sk_rcv+0x1d57/0x2c20 net/tipc/socket.c:2524
 tipc_node_xmit+0x36f/0xd80 net/tipc/node.c:1703
 tipc_sk_push_backlog net/tipc/socket.c:1316 [inline]
 tipc_sk_filter_connect net/tipc/socket.c:2257 [inline]
 tipc_sk_filter_rcv+0x19d7/0x3010 net/tipc/socket.c:2366
 tipc_sk_enqueue net/tipc/socket.c:2447 [inline]
 tipc_sk_rcv+0x7e7/0x2c20 net/tipc/socket.c:2499
 tipc_node_xmit+0x36f/0xd80 net/tipc/node.c:1703
 tipc_node_xmit_skb net/tipc/node.c:1768 [inline]
 tipc_node_distr_xmit+0x277/0x390 net/tipc/node.c:1783
 tipc_sk_backlog_rcv+0x174/0x220 net/tipc/socket.c:2414
 sk_backlog_rcv include/net/sock.h:1150 [inline]
 __release_sock+0x154/0x380 net/core/sock.c:2951
 release_sock+0x60/0x1c0 net/core/sock.c:3527
 tipc_release+0xd1a/0x1640 net/tipc/socket.c:652
 __sock_release net/socket.c:652 [inline]
 sock_close+0xc9/0x220 net/socket.c:1389
 __fput+0x1fd/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f20b7b9de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f20b8986028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: 00000000000203a0 RBX: 00007f20b7e25fa0 RCX: 00007f20b7b9de99
RDX: 0000000000000000 RSI: 00002000000003c0 RDI: 0000000000000003
RBP: 00007f20b7c33eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f20b7e26038 R14: 00007f20b7e25fa0 R15: 00007ffe95670ed8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 376 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
RIP: 0010:native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
RIP: 0010:kvm_wait+0x105/0x150 arch/x86/kernel/kvm.c:1064
Code: 1b 33 04 f4 eb 87 fa 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 3f 0f b6 07 40 38 f0 75 10 66 90 0f 00 2d cd 1b 33 04 fb f4 <e9> 5e ff ff ff fb e9 58 ff ff ff e8 eb 20 c5 03 89 f9 80 e1 07 38
RSP: 0018:ffffc900017078c0 EFLAGS: 00000246
RAX: 0000000000000003 RBX: ffff888123509e98 RCX: ffffffff85012019
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff888123509e98
RBP: ffffc90001707950 R08: ffff888123509e98 R09: 1ffff110246a13d3
R10: dffffc0000000000 R11: ffffed10246a13d4 R12: 1ffff110246a13d3
R13: ffff8881f6f38cd4 R14: dffffc0000000000 R15: 1ffff920002e0f18
FS:  000055555e438500(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f20b7beb580 CR3: 0000000112092000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:603 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x687/0xc40 kernel/locking/qspinlock.c:511
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath+0x47/0x50 arch/x86/include/asm/qspinlock.h:51
 queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:127 [inline]
 _raw_spin_lock_bh+0xe4/0xf0 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 lock_sock_nested+0x90/0x290 net/core/sock.c:3515
 lock_sock include/net/sock.h:1818 [inline]
 tipc_release+0xb3/0x1640 net/tipc/socket.c:639
 __sock_release net/socket.c:652 [inline]
 sock_close+0xc9/0x220 net/socket.c:1389
 __fput+0x1fd/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0x9b/0xb0 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f20b7b9de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe95671038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f20b7e27da0 RCX: 00007f20b7b9de99
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f20b7e27da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007f20b7e27cb0 R11: 0000000000000246 R12: 000000000001d613
R13: 00007f20b7e2609c R14: 000000000001d338 R15: 00007f20b7e26090
 </TASK>

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/18 01:40 android14-6.1 c7e15f0bdc49 8aaff637 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2026/05/02 14:30 android14-6.1 1e4e23ff0f90 a0d91488 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2026/03/03 09:58 android14-6.1 6bfa51973214 28b83e23 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2026/01/22 11:05 android14-6.1 c298d33764cb a16aed1d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2025/12/10 16:26 android14-6.1 0ac176d7ef4d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2025/12/10 06:15 android14-6.1 0ac176d7ef4d d6526ea3 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2025/10/29 11:35 android14-6.1 7ca912bfce3d fd2207e7 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2025/07/08 11:15 android14-6.1 fa7e0538663e 4f67c4ae .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2025/07/07 21:09 android14-6.1 fa7e0538663e 4f67c4ae .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2025/01/26 01:10 android14-6.1 ef4fb40b87a9 9fbd772e .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2024/05/26 17:02 android14-6.1 68c821783c76 a10a183e .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2024/03/27 04:05 android14-6.1 eef3b6e52937 454571b6 .config strace log report syz C [disk image] [vmlinux] [kernel image] ci2-android-6-1-perf BUG: soft lockup in sock_close
2024/12/06 00:30 android14-6.1 182b090f35f3 29f61fce .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2024/03/27 02:54 android14-6.1 eef3b6e52937 454571b6 .config console log report syz [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2026/07/29 06:04 android14-6.1 92668decd5e0 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_close
2026/06/19 22:31 android14-6.1 9f35ca3ff66c 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1-perf BUG: soft lockup in sock_close
* Struck through repros no longer work on HEAD.