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BUG: soft lockup in sys_bind

Status: moderation: reported on 2025/06/29 03:21
Subsystems: bpf can trace
[Documentation on labels]
Reported-by: syzbot+f7cb20491f1b4f3e31f3@syzkaller.appspotmail.com
First crash: 114d, last: 28d
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 BUG: soft lockup in sys_bind 1 1 1373d 1373d 0/1 auto-closed as invalid on 2022/05/12 15:23
android-5-10 BUG: soft lockup in sys_bind 1 1 45d 45d 0/2 premoderation: reported on 2025/09/02 00:10
upstream INFO: rcu detected stall in sys_bind (2) crypto 1 1 1402d 1402d 0/29 closed as invalid on 2022/02/08 10:10
upstream INFO: rcu detected stall in sys_bind (3) sctp 1 1 557d 557d 0/29 auto-obsoleted due to no activity on 2024/07/07 00:44
linux-5.15 INFO: rcu detected stall in sys_bind 1 1 443d 443d 0/3 auto-obsoleted due to no activity on 2024/11/07 23:03
upstream INFO: rcu detected stall in sys_bind (4) mm 1 4 306d 376d 0/29 auto-obsoleted due to no activity on 2025/03/15 08:54
upstream INFO: rcu detected stall in sys_bind x25 1 1 2443d 2443d 11/29 fixed on 2019/03/06 07:43

Sample crash report:
watchdog: BUG: soft lockup - CPU#1 stuck for 144s! [dhcpcd:6011]
Modules linked in:
irq event stamp: 23821931
hardirqs last  enabled at (23821930): [<ffffffff81a7f417>] note_gp_changes+0x237/0x300 kernel/rcu/tree.c:1326
hardirqs last disabled at (23821931): [<ffffffff8b663ede>] sysvec_apic_timer_interrupt+0xe/0xc0 arch/x86/kernel/apic/apic.c:1050
softirqs last  enabled at (23821922): [<ffffffff8185ae7a>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last  enabled at (23821922): [<ffffffff8185ae7a>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last  enabled at (23821922): [<ffffffff8185ae7a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
softirqs last disabled at (23821925): [<ffffffff8185ae7a>] __do_softirq kernel/softirq.c:613 [inline]
softirqs last disabled at (23821925): [<ffffffff8185ae7a>] invoke_softirq kernel/softirq.c:453 [inline]
softirqs last disabled at (23821925): [<ffffffff8185ae7a>] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
CPU: 1 UID: 0 PID: 6011 Comm: dhcpcd Not tainted 6.16.0-rc2-syzkaller-g190113989ae0 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:lock_is_held_type+0x9/0x190 kernel/locking/lockdep.c:5928
Code: eb b5 e8 1a fc ff ff 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 41 57 41 56 <41> 55 41 54 53 48 83 ec 10 65 48 8b 05 a6 a4 36 07 48 89 44 24 08
RSP: 0018:ffffc90000a086c0 EFLAGS: 00000202
RAX: 1ffffffff1c28801 RBX: 0000000000000001 RCX: 21fd5375895a8400
RDX: ffff8880256f5a00 RSI: 00000000ffffffff RDI: ffffffff8e13eda0
RBP: ffffc90000a087d8 R08: ffffc90000a0876f R09: 0000000000000000
R10: ffffc90000a08760 R11: fffff520001410ee R12: 0000000000000001
R13: ffffc90000a08760 R14: ffff8880769b1980 R15: ffffffff8e00de48
FS:  00007f383044b740(0000) GS:ffff888125d51000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555e1d1da4b0 CR3: 0000000027984000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 bpf_prog_run_array include/linux/bpf.h:2223 [inline]
 trace_call_bpf+0x1f4/0x850 kernel/trace/bpf_trace.c:146
 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:10866
 do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 perf_trace_lock_acquire+0x335/0x410 include/trace/events/lock.h:24
 __do_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x311/0x360 kernel/locking/lockdep.c:5834
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2257 [inline]
 bpf_trace_run1+0x1a2/0x4b0 kernel/trace/bpf_trace.c:2298
 __bpf_trace_rcu_utilization+0xa1/0xf0 include/trace/events/rcu.h:27
 __do_trace_rcu_utilization include/trace/events/rcu.h:27 [inline]
 trace_rcu_utilization+0x1ad/0x1d0 include/trace/events/rcu.h:27
 rcu_core+0x1336/0x1710 kernel/rcu/tree.c:2840
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline]
 sysvec_irq_work+0xa3/0xc0 arch/x86/kernel/irq_work.c:17
 </IRQ>
 <TASK>
 asm_sysvec_irq_work+0x1a/0x20 arch/x86/include/asm/idtentry.h:738
RIP: 0010:rcu_read_unlock_special+0x87/0x4c0 kernel/rcu/tree_plugin.h:694
Code: f1 f1 f1 00 f2 f2 f2 4a 89 04 2b 66 42 c7 44 2b 09 f3 f3 42 c6 44 2b 0b f3 65 44 8b 35 b2 15 f5 10 41 f7 c6 00 00 f0 00 74 49 <48> c7 44 24 40 0e 36 e0 45 4a c7 04 2b 00 00 00 00 66 42 c7 44 2b
RSP: 0018:ffffc9000aee7be0 EFLAGS: 00000206
RAX: 21fd5375895a8400 RBX: 1ffff920015dcf84 RCX: 21fd5375895a8400
RDX: 0000000000000006 RSI: ffffffff8d9820ce RDI: ffffffff8be28b80
RBP: ffffc9000aee7cc8 R08: ffffffff8fa10df7 R09: 1ffffffff1f421be
R10: dffffc0000000000 R11: fffffbfff1f421bf R12: ffffffff8e144100
R13: dffffc0000000000 R14: 0000000000000246 R15: 0000000000000002
 __rcu_read_unlock+0x84/0xe0 kernel/rcu/tree_plugin.h:438
 rcu_read_unlock include/linux/rcupdate.h:873 [inline]
 packet_do_bind+0x2be/0xcd0 net/packet/af_packet.c:3327
 __sys_bind_socket net/socket.c:1810 [inline]
 __sys_bind+0x2c3/0x3e0 net/socket.c:1841
 __do_sys_bind net/socket.c:1846 [inline]
 __se_sys_bind net/socket.c:1844 [inline]
 __x64_sys_bind+0x7a/0x90 net/socket.c:1844
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f38305502d7
Code: 44 00 00 48 83 ec 10 48 63 c9 48 63 ff 45 31 c9 68 20 01 00 00 45 31 c0 e8 56 51 f8 ff 48 83 c4 18 c3 90 b8 31 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d f1 ea 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffd082cd2a8 EFLAGS: 00000213 ORIG_RAX: 0000000000000031
RAX: ffffffffffffffda RBX: 0000555e2711c920 RCX: 00007f38305502d7
RDX: 0000000000000014 RSI: 00007ffd082cd2c0 RDI: 0000000000000003
RBP: 0000555e1d1da4b0 R08: 00007f383061fac0 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000213 R12: 0000000000000000
R13: 0000555e2711cab0 R14: 0000000000000000 R15: 0000555e1d1efac0
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5984 Comm: syz.0.9 Not tainted 6.16.0-rc2-syzkaller-g190113989ae0 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:error_entry+0xcc/0x140 arch/x86/entry/entry_64.S:1050
Code: 48 39 8c 24 88 00 00 00 74 3c 89 c8 48 39 84 24 88 00 00 00 74 28 48 81 bc 24 88 00 00 00 43 18 00 81 75 03 0f 01 f8 0f ae e8 <2e> 0f 1f 84 00 00 00 00 00 48 8d 44 24 08 90 e9 90 fe 68 0a 48 89
RSP: 0018:ffffc90000006e60 EFLAGS: 00000002
RAX: 000000008100176a RBX: 0000000000000000 RCX: ffffffff8100176a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000002c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f12dfcb06c0(0000) GS:ffff888125c51000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc66eb6e38 CR3: 000000007697c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2f/0x70 kernel/kcov.c:217
Code: 8b 04 24 65 48 8b 0c 25 08 f0 9c 92 65 8b 15 d8 93 dc 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 <74> 2c 8b 91 18 16 00 00 83 fa 02 75 21 48 8b 91 20 16 00 00 48 8b
RSP: 0018:ffffc90000006f18 EFLAGS: 00000246
RAX: ffffffff81c9c62c RBX: 000000000000002c RCX: ffff88802f345a00
RDX: 0000000000000100 RSI: ffffc90000006fc0 RDI: 000000000000002c
RBP: ffffc90000007058 R08: 0000000000000000 R09: ffffffff81cb8cc7
R10: dffffc0000000000 R11: fffff91ffff8ea05 R12: 1ffff92000000df4
R13: 000000000000000d R14: ffffc90000006fc0 R15: ffffc90000006fe0
 perf_trace_buf_alloc+0x1c/0x2a0 kernel/trace/trace_event_perf.c:399
 do_perf_trace_lock include/trace/events/lock.h:50 [inline]
 perf_trace_lock+0x18d/0x3b0 include/trace/events/lock.h:50
 __do_trace_lock_release include/trace/events/lock.h:69 [inline]
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0x3b2/0x3e0 kernel/locking/lockdep.c:5882
 rcu_lock_release include/linux/rcupdate.h:341 [inline]
 rcu_read_unlock+0x93/0xa0 include/linux/rcupdate.h:871
 trace_call_bpf+0x7dd/0x850 kernel/trace/bpf_trace.c:125
 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:10866
 do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 perf_trace_lock_acquire+0x335/0x410 include/trace/events/lock.h:24
 __do_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x311/0x360 kernel/locking/lockdep.c:5834
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4643 [inline]
 kmem_cache_free+0x18f/0x400 mm/slub.c:4745
 kfree_skb_reason include/linux/skbuff.h:1275 [inline]
 kfree_skb include/linux/skbuff.h:1284 [inline]
 hsr_forward_skb+0x1ac6/0x2860 net/hsr/hsr_forward.c:-1
 send_hsr_supervision_frame+0x612/0xb30 net/hsr/hsr_device.c:358
 hsr_announce+0x1d2/0x360 net/hsr/hsr_device.c:415
 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1798 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline]
RIP: 0010:perf_trace_lock_acquire+0xe8/0x410 include/trace/events/lock.h:24
Code: 0f 45 f8 48 89 7c 24 28 e8 85 b3 c4 09 49 89 c5 49 8d 5e 60 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 78 5a 86 00 <48> 8b 03 48 89 44 24 08 e8 7b e0 c8 09 89 c3 83 f8 08 0f 83 7e 02
RSP: 0018:ffffc90004d270a0 EFLAGS: 00000246
RAX: 1ffffffff1c01bc8 RBX: ffffffff8e00de40 RCX: 000000008b8bd505
RDX: 0000000000000000 RSI: ffffffff8e13eda0 RDI: ffffffff8b8bd580
RBP: ffffc90004d271a0 R08: 0000000000000002 R09: 0000000000000000
R10: dffffc0000000000 R11: fffff91ffff8e605 R12: 1ffff920009a4e1c
R13: 000000000000000d R14: ffffffff8e00dde0 R15: dffffc0000000000
 __do_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x311/0x360 kernel/locking/lockdep.c:5834
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 trace_call_bpf+0xd4/0x850 kernel/trace/bpf_trace.c:-1
 perf_trace_run_bpf_submit+0x78/0x170 kernel/events/core.c:10866
 do_perf_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 perf_trace_lock_acquire+0x335/0x410 include/trace/events/lock.h:24
 __do_trace_lock_acquire include/trace/events/lock.h:24 [inline]
 trace_lock_acquire include/trace/events/lock.h:24 [inline]
 lock_acquire+0x311/0x360 kernel/locking/lockdep.c:5834
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 save_stack+0xf5/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1248 [inline]
 __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706
 __slab_free+0x326/0x400 mm/slub.c:4554
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:385
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 bpf_prog_alloc_no_stats+0xdb/0x4e0 kernel/bpf/core.c:108
 bpf_prog_alloc+0x3c/0x1a0 kernel/bpf/core.c:146
 bpf_prog_load+0x735/0x1930 kernel/bpf/syscall.c:2882
 __sys_bpf+0x5f1/0x860 kernel/bpf/syscall.c:5836
 __do_sys_bpf kernel/bpf/syscall.c:5943 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5941
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f12ded8e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f12dfcb0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f12defb5fa0 RCX: 00007f12ded8e929
RDX: 0000000000000090 RSI: 0000200000000a40 RDI: 0000000000000005
RBP: 00007f12dee10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f12defb5fa0 R15: 00007ffcce573c48
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/25 03:13 bpf 190113989ae0 26d77996 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce BUG: soft lockup in sys_bind
2025/09/18 21:44 linux-next 8f7f8b1b3f4c e2beed91 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: rcu detected stall in sys_bind
* Struck through repros no longer work on HEAD.