BUG: soft lockup in ip_list_rcv (3)

Status: upstream: reported C repro on 2026/10/04 02:09
Reported-by: syzbot+8b4cea3d423a19a01900@syzkaller.appspotmail.com
First crash: 13h49m, last: 13h49m
▶ ▼ Similar bugs (19)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 BUG: soft lockup in ip_list_rcv 1 20 740d 894d 0/2 auto-obsoleted due to no activity on 2024/12/22 22:06
upstream BUG: soft lockup in ip_list_rcv (2) kvm 1 8 1622d 1622d 0/29 auto-closed as invalid on 2022/06/25 08:42
upstream BUG: soft lockup in ip_list_rcv net 1 1 2123d 2123d 0/29 auto-closed as invalid on 2021/03/11 09:36
android-6-1 BUG: soft lockup in ip_list_rcv 1 2 792d 815d 0/2 auto-obsoleted due to no activity on 2024/10/31 19:10
upstream INFO: rcu detected stall in ip_list_rcv (6) prio:low net 1 syz, C done done 62 24d 1035d 0/29 upstream: reported C repro on 2023/12/04 09:45
android-5-15 BUG: soft lockup in ip_list_rcv (2) 1 1 557d 557d 0/2 auto-obsoleted due to no activity on 2025/06/24 13:43
android-5-10 BUG: soft lockup in ip_list_rcv 1 1 788d 788d 0/2 auto-obsoleted due to no activity on 2024/11/04 20:30
linux-6.6 INFO: rcu detected stall in ip_list_rcv 1 8 44d 304d 0/2 upstream: reported on 2025/12/04 02:09
linux-5.15 INFO: rcu detected stall in ip_list_rcv (3) 1 2 21h42m 13d 0/3 upstream: reported on 2026/09/21 15:44
linux-6.1 INFO: rcu detected stall in ip_list_rcv (2) 1 1 614d 614d 0/3 auto-obsoleted due to no activity on 2025/05/08 11:17
linux-5.15 INFO: rcu detected stall in ip_list_rcv 1 2 750d 806d 0/3 auto-obsoleted due to no activity on 2024/12/22 19:35
linux-6.1 INFO: rcu detected stall in ip_list_rcv 1 1 766d 766d 0/3 auto-obsoleted due to no activity on 2024/12/06 18:02
linux-5.15 INFO: rcu detected stall in ip_list_rcv (2) 1 2 266d 345d 0/3 auto-obsoleted due to no activity on 2026/04/21 10:23
upstream INFO: rcu detected stall in ip_list_rcv (5) lsm netfilter 1 3 1178d 1237d 0/29 auto-obsoleted due to no activity on 2023/10/11 22:12
upstream INFO: rcu detected stall in ip_list_rcv (4) netfilter 1 1 1553d 1553d 0/29 auto-closed as invalid on 2022/09/01 16:20
upstream INFO: rcu detected stall in ip_list_rcv (2) netfilter 1 3 2050d 2129d 0/29 auto-closed as invalid on 2021/05/23 12:59
linux-6.1 INFO: rcu detected stall in ip_list_rcv (3) 1 1 386d 386d 0/3 auto-obsoleted due to no activity on 2025/12/22 08:55
upstream INFO: rcu detected stall in ip_list_rcv (3) net 1 1 1742d 1742d 0/29 closed as invalid on 2022/02/08 10:10
linux-6.1 INFO: rcu detected stall in ip_list_rcv (4) 1 6 35d 97d 0/3 upstream: reported on 2026/06/29 13:08

Sample crash report:
RBP: 0000200000000300 R08: 0000000000000000 R09: 00007ffc168db9d0
R10: ffffffffffffffff R11: 0000000000000246 R12: 00000000000f4240
R13: 0000000000000002 R14: 00007ffc168db9bc R15: 00007ffc168db9c0
 </TASK>
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz-executor302:313]
Modules linked in:
CPU: 0 PID: 313 Comm: syz-executor302 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:qdisc_run_end include/net/sch_generic.h:205 [inline]
RIP: 0010:__dev_xmit_skb net/core/dev.c:3909 [inline]
RIP: 0010:__dev_queue_xmit+0x19e0/0x2d60 net/core/dev.c:4274
Code: f4 ff ff e8 12 68 a8 fd 49 8d 5d 10 48 b9 00 00 00 00 00 fc ff df 41 0f b6 04 0f 49 89 cf 84 c0 0f 85 39 09 00 00 8b 1b 89 de <81> e6 00 01 00 00 31 ff e8 93 6b a8 fd 81 e3 00 01 00 00 75 2c e8
RSP: 0018:ffffc900000065c0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000174 RCX: dffffc0000000000
RDX: 0000000000000100 RSI: 0000000000000174 RDI: 0000000000000000
RBP: ffffc90000006798 R08: ffff88810b3540d7 R09: 1ffff1102166a81a
R10: dffffc0000000000 R11: ffffed102166a81b R12: ffff88811b81bc78
R13: ffff88811b750000 R14: 0000000000000002 R15: dffffc0000000000
FS:  000055557250e480(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000008000000002 CR3: 0000000124f18000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 dev_queue_xmit+0x17/0x20 net/core/dev.c:4355
 neigh_hh_output include/net/neighbour.h:501 [inline]
 neigh_output include/net/neighbour.h:515 [inline]
 ip_finish_output2+0xb1f/0xec0 net/ipv4/ip_output.c:228
 __ip_finish_output+0x163/0x360 net/ipv4/ip_output.c:-1
 ip_finish_output+0x31/0x220 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:294 [inline]
 ip_output+0x1ea/0x390 net/ipv4/ip_output.c:434
 dst_output include/net/dst.h:453 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0x10cd/0x1c30 net/ipv4/ip_output.c:538
 ip_queue_xmit+0x4d/0x70 net/ipv4/ip_output.c:552
 __tcp_transmit_skb+0x1e23/0x35f0 net/ipv4/tcp_output.c:1404
 tcp_transmit_skb net/ipv4/tcp_output.c:1422 [inline]
 tcp_write_xmit+0x16f1/0x5f40 net/ipv4/tcp_output.c:2718
 __tcp_push_pending_frames+0x99/0x2f0 net/ipv4/tcp_output.c:2903
 tcp_push_pending_frames include/net/tcp.h:1916 [inline]
 tcp_data_snd_check net/ipv4/tcp_input.c:5574 [inline]
 tcp_rcv_established+0xdb6/0x1ad0 net/ipv4/tcp_input.c:5985
 tcp_v4_do_rcv+0x591/0x9f0 net/ipv4/tcp_ipv4.c:1726
 tcp_v4_rcv+0x221a/0x2880 net/ipv4/tcp_ipv4.c:2138
 ip_protocol_deliver_rcu+0x360/0x760 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip_local_deliver+0x2dd/0x520 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:463 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:577 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:628 [inline]
 ip_sublist_rcv+0x75f/0x8b0 net/ipv4/ip_input.c:636
 ip_list_rcv+0x3e4/0x430 net/ipv4/ip_input.c:671
 __netif_receive_skb_list_ptype net/core/dev.c:5602 [inline]
 __netif_receive_skb_list_core+0x57e/0x770 net/core/dev.c:5650
 __netif_receive_skb_list net/core/dev.c:5702 [inline]
 netif_receive_skb_list_internal+0x7f8/0xaa0 net/core/dev.c:5793
 gro_normal_list net/core/dev.c:5947 [inline]
 gro_normal_one net/core/dev.c:5960 [inline]
 napi_skb_finish net/core/dev.c:6297 [inline]
 napi_gro_receive+0x45b/0x8b0 net/core/dev.c:6327
 receive_buf+0x2ff7/0x4c20 drivers/net/virtio_net.c:1240
 virtnet_receive drivers/net/virtio_net.c:1504 [inline]
 virtnet_poll+0x5cd/0xfb0 drivers/net/virtio_net.c:1620
 __napi_poll+0xbb/0x580 net/core/dev.c:7109
 napi_poll net/core/dev.c:7176 [inline]
 net_rx_action+0x37f/0x910 net/core/dev.c:7266
 handle_softirqs+0x250/0x560 kernel/softirq.c:583
 __do_softirq kernel/softirq.c:621 [inline]
 invoke_softirq kernel/softirq.c:443 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:670
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:682
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:fd_install+0x7b/0x2a0 fs/file.c:588
Code: fb 85 8f ff 4d 8d 7c 24 04 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 fd 01 00 00 41 80 3f 01 <0f> 84 f7 00 00 00 49 89 dd 49 83 c4 20 4c 89 e0 48 c1 e8 03 48 b9
RSP: 0018:ffffc90000a97d00 EFLAGS: 00000297
RAX: 0000000000000000 RBX: ffff88811b812000 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffff88811b812000 RDI: ffffffff81b847c5
RBP: ffffc90000a97d30 R08: ffffc90000a97cc7 R09: 1ffff92000152f98
R10: dffffc0000000000 R11: fffff52000152f99 R12: ffff88812547b0c0
R13: ffff88810b6f46a8 R14: 0000000000000006 R15: ffff88812547b0c4
 __do_sys_perf_event_open kernel/events/core.c:12678 [inline]
 __se_sys_perf_event_open+0x1a16/0x1bb0 kernel/events/core.c:12249
 __x64_sys_perf_event_open+0xbf/0xd0 kernel/events/core.c:12249
 x64_sys_call+0x50d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:299
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7ffbd4e82d79
Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc168db988 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 00007ffbd4e82d79
RDX: 0000000000000000 RSI: ffffffffffffffff RDI: 0000200000000300
RBP: 0000200000000300 R08: 0000000000000000 R09: 00007ffc168db9d0
R10: ffffffffffffffff R11: 0000000000000246 R12: 00000000000f4240
R13: 0000000000000002 R14: 00007ffc168db9bc R15: 00007ffc168db9c0
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at default_idle+0xf/0x20 arch/x86/kernel/process.c:729

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/04 02:07 android13-5.15-lts f5eaed2bbe33 57bbd979 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-android-5-15-perf BUG: soft lockup in ip_list_rcv
* Struck through repros no longer work on HEAD.