------------[ cut here ]------------
WARNING: CPU: 1 PID: 24772 at net/ipv4/tcp_input.c:2573 tcp_cwnd_reduction+0x321/0x380 net/ipv4/tcp_input.c:2573
Modules linked in:
CPU: 1 PID: 24772 Comm: syz-executor.4 Tainted: G        W         5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tcp_cwnd_reduction+0x321/0x380 net/ipv4/tcp_input.c:2573
Code: 38 09 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f e9 b2 52 de f9 e8 ad 52 de f9 41 39 ec 41 0f 4e ec eb 89 e8 9f 52 de f9 <0f> 0b eb d6 e8 36 10 24 fa e9 38 fd ff ff e8 2c 10 24 fa e9 20 fe
RSP: 0018:ffffc90000dc0680 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88802e383d40 RCX: 0000000000000100
RDX: ffff88801ceb0000 RSI: ffffffff87973791 RDI: 0000000000000003
RBP: 000000000000000a R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff879734e8 R11: 0000000000000000 R12: 000000000000000a
R13: 0000000000000000 R14: 0000000000000008 R15: ffff88802e383d40
FS:  0000000002c44400(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021000000 CR3: 000000009f354000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 tcp_cong_control net/ipv4/tcp_input.c:3446 [inline]
 tcp_ack+0x4117/0x59a0 net/ipv4/tcp_input.c:3850
 tcp_rcv_established+0x5d7/0x2130 net/ipv4/tcp_input.c:5879
 tcp_v6_do_rcv+0x41d/0x12b0 net/ipv6/tcp_ipv6.c:1502
 tcp_v6_rcv+0x31db/0x36d0 net/ipv6/tcp_ipv6.c:1744
 ip6_protocol_deliver_rcu+0x2e9/0x17f0 net/ipv6/ip6_input.c:422
 ip6_input_finish+0x7f/0x160 net/ipv6/ip6_input.c:463
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:472
 dst_input include/net/dst.h:458 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 ipv6_rcv+0x28c/0x3c0 net/ipv6/ip6_input.c:297
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5486
 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5600
 process_backlog+0x232/0x6c0 net/core/dev.c:6464
 __napi_poll+0xaf/0x440 net/core/dev.c:7019
 napi_poll net/core/dev.c:7086 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:7173
 __do_softirq+0x29b/0x9bd kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:finish_task_switch.isra.0+0x23c/0xa50 kernel/sched/core.c:4557
Code: 8b 3a 4c 89 e7 48 c7 02 00 00 00 00 ff d1 4d 85 ff 75 bf 4c 89 e7 e8 13 49 d4 07 e8 4e cc 2b 00 fb 65 48 8b 1c 25 00 f0 01 00 <48> 8d bb 10 15 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1
RSP: 0018:ffffc900177278b0 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff88801ceb0000 RCX: 1ffffffff1bd70a9
RDX: 0000000000000000 RSI: ffffffff817b9fd1 RDI: ffffffff814fd332
RBP: ffffc900177278f0 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff817b9fb8 R11: 0000000000000001 R12: ffff8880b9d35a40
R13: ffff88801bed3880 R14: 0000000000000000 R15: ffff8880b9d35a58
 context_switch kernel/sched/core.c:4686 [inline]
 __schedule+0x93c/0x2710 kernel/sched/core.c:5940
 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6100
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35
 try_to_wake_up+0xa50/0x1540 kernel/sched/core.c:3846
 wake_up_process kernel/sched/core.c:3909 [inline]
 wake_up_q+0x7e/0xf0 kernel/sched/core.c:935
 futex_wake+0x3e9/0x490 kernel/futex.c:1633
 do_futex+0x2a0/0x1770 kernel/futex.c:3735
 __do_sys_futex+0xdc/0x3b0 kernel/futex.c:3807
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665d9
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:0000000000a9fb98 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000004665d9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000056c040
RBP: 000000000056c038 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000005713e0
R13: 0000000000a9fca0 R14: 000000000056bf80 R15: 000000000016483a