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BUG: soft lockup in sock_read_iter (2)

Status: premoderation: reported on 2025/09/08 00:15
Reported-by: syzbot+1b04d61f70936b1b11dc@syzkaller.appspotmail.com
First crash: 4d13h, last: 4d13h
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 BUG: soft lockup in sock_read_iter 1 10 392d 523d 0/2 auto-obsoleted due to no activity on 2024/11/14 07:45
android-6-1 BUG: soft lockup in sock_read_iter 1 2 138d 177d 0/2 auto-obsoleted due to no activity on 2025/07/26 10:57
android-5-10 BUG: soft lockup in sock_read_iter 1 2 62d 74d 0/2 premoderation: reported on 2025/06/29 15:05
linux-6.1 INFO: rcu detected stall in sock_read_iter 1 1 240d 240d 0/3 auto-obsoleted due to no activity on 2025/04/25 05:42
upstream INFO: rcu detected stall in sock_read_iter net 1 1 1072d 1072d 0/29 auto-obsoleted due to no activity on 2022/12/05 11:10
upstream INFO: rcu detected stall in sock_read_iter (2) net 1 1 330d 330d 0/29 auto-obsoleted due to no activity on 2025/01/14 23:11

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 246s! [syz-executor:275]
Modules linked in:
CPU: 0 PID: 275 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:434 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x591/0xc40 kernel/locking/qspinlock.c:511
Code: 0f 85 33 01 00 00 41 c6 45 00 00 41 0f b6 04 17 84 c0 0f 85 46 01 00 00 48 8b 44 24 10 c6 00 01 41 bd 00 80 ff ff eb 07 f3 90 <41> ff c5 74 5b 41 0f b6 04 16 84 c0 75 35 80 3b 00 75 eb 48 89 df
RSP: 0018:ffffc90000cd76c0 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffff888120c02898 RCX: ffffffff84f3cd32
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff888120c02898
RBP: ffffc90000cd77b0 R08: dffffc0000000000 R09: ffffed1024180514
R10: ffffed1024180514 R11: 1ffff11024180513 R12: 1ffff1103ee00001
R13: 00000000ffffa2b5 R14: 1ffff11024180513 R15: 1ffff11024180513
FS:  000055557fdc1500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2a922b CR3: 0000000121772000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 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+0xd8/0xe0 kernel/locking/spinlock.c:178
 spin_lock_bh include/linux/spinlock.h:356 [inline]
 lock_sock_nested+0x92/0x280 net/core/sock.c:3507
 lock_sock include/net/sock.h:1769 [inline]
 tcp_recvmsg+0x1f2/0x810 net/ipv4/tcp.c:2697
 inet_recvmsg+0x13b/0x470 net/ipv4/af_inet.c:875
 sock_recvmsg_nosec net/socket.c:1020 [inline]
 sock_recvmsg net/socket.c:1038 [inline]
 sock_read_iter+0x2d3/0x380 net/socket.c:1111
 call_read_iter include/linux/fs.h:2276 [inline]
 new_sync_read fs/read_write.c:389 [inline]
 vfs_read+0x41e/0x8c0 fs/read_write.c:470
 ksys_read+0x140/0x240 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x7b/0x90 fs/read_write.c:621
 x64_sys_call+0x2f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f71a7b8d5bd
Code: a8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb b5 e8 a8 48 00 00 0f 1f 84 00 00 00 00 00 80 3d a1 af 20 00 00 74 17 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 5b c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec
RSP: 002b:00007ffc6d28ea28 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007ffc6d28eb30 RCX: 00007f71a7b8d5bd
RDX: 0000000000000004 RSI: 00007ffc6d28ea3c RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000104 R09: 001a7b90868be88c
R10: 000000868e2b1fdd R11: 0000000000000246 R12: 00007ffc6d28ee50
R13: 0000000000000004 R14: 00007ffc6d28ea3c R15: 00007ffc6d28ead0
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12858 Comm: syz.1.5429 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:native_halt arch/x86/include/asm/irqflags.h:57 [inline]
RIP: 0010:halt arch/x86/include/asm/irqflags.h:98 [inline]
RIP: 0010:kvm_wait+0xcc/0x140 arch/x86/kernel/kvm.c:1058
Code: 20 f6 44 24 21 02 75 24 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 48 0f b6 07 40 38 f0 75 a6 66 90 0f 00 2d d5 ab 13 04 f4 <eb> 9a fa 48 89 f8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 3f 0f b6 07
RSP: 0018:ffffc900001af720 EFLAGS: 00000046
RAX: 0000000000000003 RBX: ffff8881f7127c40 RCX: ffffffff84f3cd32
RDX: dffffc0000000000 RSI: 0000000000000003 RDI: ffff8881f7127c40
RBP: ffffc900001af7b0 R08: dffffc0000000000 R09: ffffed103ee24f89
R10: ffffed103ee24f89 R11: 1ffff1103ee24f88 R12: 1ffff1103ee20001
R13: ffff8881f7138cd4 R14: dffffc0000000000 R15: 1ffff92000035ee4
FS:  00007f4e19c0f6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000012a5bb000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 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+0x690/0xc40 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_irqsave include/linux/spinlock_api_smp.h:111 [inline]
 _raw_spin_lock_irqsave+0x108/0x110 kernel/locking/spinlock.c:162
 lock_timer_base+0x127/0x270 kernel/time/timer.c:1005
 __mod_timer+0x10a/0xb30 kernel/time/timer.c:1078
 add_timer+0x68/0x80 kernel/time/timer.c:1218
 __queue_delayed_work+0x173/0x200 kernel/workqueue.c:1686
 queue_delayed_work_on+0xdb/0x150 kernel/workqueue.c:1711
 queue_delayed_work include/linux/workqueue.h:525 [inline]
 schedule_delayed_monitor_work kernel/rcu/tree.c:3216 [inline]
 kvfree_call_rcu+0x436/0x7a0 kernel/rcu/tree.c:3472
 trie_delete_elem+0x572/0x720 kernel/bpf/lpm_trie.c:545
 bpf_prog_18a85c48b7f32964+0x3d/0x41
 bpf_dispatcher_nop_func include/linux/bpf.h:987 [inline]
 __bpf_prog_run include/linux/filter.h:603 [inline]
 bpf_prog_run include/linux/filter.h:610 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2283 [inline]
 bpf_trace_run3+0x113/0x270 kernel/trace/bpf_trace.c:2323
 __bpf_trace_timer_start+0x2b/0x40 include/trace/events/timer.h:53
 trace_timer_start include/trace/events/timer.h:53 [inline]
 enqueue_timer+0x337/0x480 kernel/time/timer.c:615
 __mod_timer+0x79f/0xb30 kernel/time/timer.c:-1
 mod_timer+0x1f/0x30 kernel/time/timer.c:1172
 sk_reset_timer+0x22/0xb0 net/core/sock.c:3390
 tcp_send_delayed_ack+0x30a/0x400 net/ipv4/tcp_output.c:3968
 __tcp_ack_snd_check+0x437/0x910 net/ipv4/tcp_input.c:5635
 tcp_ack_snd_check net/ipv4/tcp_input.c:5676 [inline]
 tcp_rcv_established+0xa41/0x1a20 net/ipv4/tcp_input.c:6120
 tcp_v4_do_rcv+0x446/0xa10 net/ipv4/tcp_ipv4.c:1683
 tcp_v4_rcv+0x233c/0x2a80 net/ipv4/tcp_ipv4.c:2114
 ip_protocol_deliver_rcu+0x325/0x6e0 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x24e/0x410 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ip_local_deliver+0x1d8/0x320 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:463 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline]
 ip_sublist_rcv+0x773/0x880 net/ipv4/ip_input.c:639
 ip_list_rcv+0x3da/0x420 net/ipv4/ip_input.c:674
 __netif_receive_skb_list_ptype net/core/dev.c:5628 [inline]
 __netif_receive_skb_list_core+0x59e/0x770 net/core/dev.c:5676
 __netif_receive_skb_list net/core/dev.c:5728 [inline]
 netif_receive_skb_list_internal+0x7d2/0xa60 net/core/dev.c:5819
 gro_normal_list include/net/gro.h:433 [inline]
 napi_complete_done+0x36f/0x790 net/core/dev.c:6160
 virtqueue_napi_complete drivers/net/virtio_net.c:403 [inline]
 virtnet_poll+0x991/0x1150 drivers/net/virtio_net.c:1717
 __napi_poll+0xd0/0x5e0 net/core/dev.c:6594
 napi_poll net/core/dev.c:6661 [inline]
 net_rx_action+0x49b/0xaa0 net/core/dev.c:6775
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq+0xb/0xd kernel/softirq.c:680
 do_softirq+0xc6/0x120 kernel/softirq.c:524
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x75/0x80 kernel/softirq.c:448
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 xdp_test_run_batch net/bpf/test_run.c:340 [inline]
 bpf_test_run_xdp_live+0x175d/0x19e0 net/bpf/test_run.c:362
 bpf_prog_test_run_xdp+0x6f1/0xe50 net/bpf/test_run.c:1390
 bpf_prog_test_run+0x3e3/0x630 kernel/bpf/syscall.c:3665
 __sys_bpf+0x56d/0x780 kernel/bpf/syscall.c:5020
 __do_sys_bpf kernel/bpf/syscall.c:5106 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5104 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5104
 x64_sys_call+0x488/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f4e18d8ebe9
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:00007f4e19c0f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007f4e18fc5fa0 RCX: 00007f4e18d8ebe9
RDX: 0000000000000048 RSI: 0000200000000600 RDI: 000000000000000a
RBP: 00007f4e18e11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4e18fc6038 R14: 00007f4e18fc5fa0 R15: 00007ffcd5584a18
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/08 00:14 android14-6.1 499d2a0ffd4f d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 BUG: soft lockup in sock_read_iter
* Struck through repros no longer work on HEAD.