------------[ cut here ]------------
WARNING: CPU: 1 PID: 19566 at net/ipv4/tcp_input.c:2605 tcp_cwnd_reduction net/ipv4/tcp_input.c:2605 [inline]
WARNING: CPU: 1 PID: 19566 at net/ipv4/tcp_input.c:2605 tcp_cong_control net/ipv4/tcp_input.c:3478 [inline]
WARNING: CPU: 1 PID: 19566 at net/ipv4/tcp_input.c:2605 tcp_ack+0x2cf2/0x42f0 net/ipv4/tcp_input.c:3882
Modules linked in:
CPU: 1 PID: 19566 Comm: syz-executor.1 Not tainted 5.15.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tcp_cwnd_reduction net/ipv4/tcp_input.c:2605 [inline]
RIP: 0010:tcp_cong_control net/ipv4/tcp_input.c:3478 [inline]
RIP: 0010:tcp_ack+0x2cf2/0x42f0 net/ipv4/tcp_input.c:3882
Code: 04 01 84 c0 0f 85 d5 15 00 00 48 8b 84 24 a0 00 00 00 80 60 01 7f 49 bc 00 00 00 00 00 fc ff df e9 f1 dc ff ff e8 1e 07 eb f8 <0f> 0b 49 bc 00 00 00 00 00 fc ff df e9 ea f9 ff ff e8 08 07 eb f8
RSP: 0018:ffffc90004867520 EFLAGS: 00010283
RAX: ffffffff88976ec2 RBX: ffff88802d8f095c RCX: 0000000000040000
RDX: ffffc90006121000 RSI: 0000000000007bd9 RDI: 0000000000007bda
RBP: ffffc900048677d0 R08: ffffffff88976310 R09: fffffbfff1fa31d8
R10: fffffbfff1fa31d8 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000005706
FS:  00007f44ff2ff700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555563b5708 CR3: 0000000084702000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcp_rcv_established+0x7d7/0x22b0 net/ipv4/tcp_input.c:5919
 tcp_v4_do_rcv+0x3a1/0x880 net/ipv4/tcp_ipv4.c:1694
 sk_backlog_rcv include/net/sock.h:1024 [inline]
 __release_sock+0x1d8/0x4c0 net/core/sock.c:2668
 __sk_flush_backlog+0x22/0x30 net/core/sock.c:2688
 sk_flush_backlog include/net/sock.h:1111 [inline]
 tcp_sendmsg_locked+0x2c03/0x4120 net/ipv4/tcp.c:1305
 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1461
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 __sys_sendto+0x560/0x720 net/socket.c:2036
 __do_sys_sendto net/socket.c:2048 [inline]
 __se_sys_sendto net/socket.c:2044 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2044
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f4501da9709
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:00007f44ff2ff188 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f4501eae020 RCX: 00007f4501da9709
RDX: 00000000fffffd46 RSI: 0000000020000240 RDI: 0000000000000003
RBP: 00007f4501e03cb4 R08: 0000000000000000 R09: 00000000000001f4
R10: 00000000000081f4 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd06d8996f R14: 00007f44ff2ff300 R15: 0000000000022000