BUG: soft lockup in tun_chr_close

Status: auto-obsoleted due to no activity on 2024/08/19 06:38
Reported-by: syzbot+854fd86eabed836c46e7@syzkaller.appspotmail.com
First crash: 843d, last: 812d
▶ ▼ Similar bugs (8)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: rcu detected stall in tun_chr_close (7) mm net 1 2 370d 450d 0/29 auto-obsoleted due to no activity on 2025/11/04 06:54
linux-6.1 INFO: rcu detected stall in tun_chr_close 1 1 1d01h 1d01h 0/3 upstream: reported on 2026/08/11 00:09
upstream INFO: rcu detected stall in tun_chr_close (4) bpf net 1 3 1667d 1737d 0/29 closed as invalid on 2022/02/08 10:00
linux-5.15 INFO: rcu detected stall in tun_chr_close (3) 1 1 124d 124d 0/3 auto-obsoleted due to no activity on 2026/07/18 10:54
linux-5.15 INFO: rcu detected stall in tun_chr_close (2) 1 1 704d 704d 0/3 auto-obsoleted due to no activity on 2024/12/15 18:42
linux-5.15 INFO: rcu detected stall in tun_chr_close 1 1 941d 941d 0/3 auto-obsoleted due to no activity on 2024/04/23 00:30
upstream INFO: rcu detected stall in tun_chr_close (5) net 1 1 1165d 1165d 0/29 auto-obsoleted due to no activity on 2023/09/01 17:23
upstream INFO: rcu detected stall in tun_chr_close (6) net mm 1 19 547d 786d 0/29 auto-obsoleted due to no activity on 2025/05/11 04:14

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 225s! [syz-executor.3:456]
Modules linked in:
CPU: 0 PID: 456 Comm: syz-executor.3 Tainted: G        W         5.15.149-syzkaller-00490-g5d96939590c0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc900053d7620 EFLAGS: 00000246
RAX: 0000000000000003 RBX: 1ffff92000a7aec8 RCX: ffffffff8154fa7f
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff8881065bfe18
RBP: ffffc900053d76d0 R08: dffffc0000000000 R09: ffffed1020cb7fc4
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881065bfe18 R14: 0000000000000003 R15: 1ffff92000a7aecc
FS:  00007fa596bc76c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2eb22000 CR3: 000000010f433000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 </IRQ>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:470 [inline]
 __pv_queued_spin_lock_slowpath+0x6bc/0xc40 kernel/locking/qspinlock.c:508
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x6cc
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 sk_psock_free_link include/linux/skmsg.h:420 [inline]
 sock_map_del_link net/core/sock_map.c:160 [inline]
 sock_map_unref+0x352/0x4d0 net/core/sock_map.c:182
 sock_hash_delete_elem+0x274/0x2f0 net/core/sock_map.c:941
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x6cc
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 kvfree+0x35/0x40 mm/util.c:664
 ptr_ring_cleanup include/linux/ptr_ring.h:671 [inline]
 __tun_detach+0x11b9/0x14c0 drivers/net/tun.c:689
 tun_detach drivers/net/tun.c:701 [inline]
 tun_chr_close+0xb8/0x140 drivers/net/tun.c:3434
 __fput+0x3fe/0x910 fs/file_table.c:280
 ____fput+0x15/0x20 fs/file_table.c:308
 task_work_run+0x129/0x190 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xc4/0xe0 kernel/entry/common.c:175
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x160 kernel/entry/common.c:301
 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fa597e52ee9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa596bc70c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007fa597f81f80 RCX: 00007fa597e52ee9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fa597e9f49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fa597f81f80 R15: 00007fff5103a1a8
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 432 Comm: syz-executor.2 Tainted: G        W         5.15.149-syzkaller-00490-g5d96939590c0 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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+0x147/0x180 arch/x86/kernel/kvm.c:918
Code: 4c 89 e8 48 c1 e8 03 42 0f b6 04 20 84 c0 44 8b 74 24 1c 75 34 41 0f b6 45 00 44 38 f0 75 10 66 90 0f 00 2d 5b 03 f3 03 fb f4 <e9> 24 ff ff ff fb e9 1e ff ff ff 44 89 e9 80 e1 07 38 c1 7c a3 4c
RSP: 0018:ffffc90005356cc0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: 1ffff92000a6ad9c RCX: 1ffffffff0d1aa9c
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8881f7137ed4
RBP: ffffc90005356d70 R08: dffffc0000000000 R09: ffffed103ee26fdb
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffff8881f7137ed4 R14: 0000000000000001 R15: 1ffff92000a6ada0
FS:  00007f04459986c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3d354a6fe0 CR3: 0000000128bea000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 pv_wait arch/x86/include/asm/paravirt.h:597 [inline]
 pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline]
 __pv_queued_spin_lock_slowpath+0x41b/0xc40 kernel/locking/qspinlock.c:473
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock include/linux/spinlock.h:187 [inline]
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
 _raw_spin_lock_bh+0x139/0x1b0 kernel/locking/spinlock.c:178
 sock_hash_delete_elem+0xb1/0x2f0 net/core/sock_map.c:937
 bpf_prog_2c29ac5cdc6b1842+0x3a/0x6cc
 bpf_dispatcher_nop_func include/linux/bpf.h:785 [inline]
 __bpf_prog_run include/linux/filter.h:625 [inline]
 bpf_prog_run include/linux/filter.h:632 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1883 [inline]
 bpf_trace_run2+0xec/0x210 kernel/trace/bpf_trace.c:1920
 __bpf_trace_kfree+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kfree include/trace/events/kmem.h:118 [inline]
 kfree+0x1f3/0x220 mm/slub.c:4569
 krealloc+0xb9/0xf0
 push_jmp_history kernel/bpf/verifier.c:2119 [inline]
 is_state_visited kernel/bpf/verifier.c:10993 [inline]
 do_check+0x2633/0xf2c0 kernel/bpf/verifier.c:11133
 do_check_common+0x909/0x1290 kernel/bpf/verifier.c:13408
 do_check_main kernel/bpf/verifier.c:13471 [inline]
 bpf_check+0x3835/0x12bf0 kernel/bpf/verifier.c:14042
 bpf_prog_load+0x12ac/0x1b50 kernel/bpf/syscall.c:2333
 __sys_bpf+0x4bc/0x760 kernel/bpf/syscall.c:4633
 __do_sys_bpf kernel/bpf/syscall.c:4737 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4735 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:4735
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f0446c23ee9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 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 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f04459980c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f0446d52f80 RCX: 00007f0446c23ee9
RDX: 0000000000000022 RSI: 0000000020000900 RDI: 0000000000000005
RBP: 00007f0446c7049e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f0446d52f80 R15: 00007ffd8cb57618
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/21 06:28 android13-5.15-lts 5d96939590c0 c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in tun_chr_close
2024/04/27 22:46 android13-5.15-lts 5d96939590c0 07b455f9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in tun_chr_close
2024/04/20 23:17 android13-5.15-lts ad06eaf051cd af24b050 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 BUG: soft lockup in tun_chr_close
* Struck through repros no longer work on HEAD.