syzbot

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WARNING: CPU: 1 PID: 8907 at net/ipv4/tcp_input.c:2615 tcp_cwnd_reduction+0x329/0x390 net/ipv4/tcp_input.c:2615
Modules linked in:
CPU: 0 PID: 8907 Comm: syz-executor.5 Not tainted 5.18.0-rc4-syzkaller-00006-gd615b5416f8a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:tcp_cwnd_reduction+0x329/0x390 net/ipv4/tcp_input.c:2615
Code: 88 09 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f e9 9a b1 a8 f9 e8 95 b1 a8 f9 44 39 e5 41 0f 4f ec eb 81 e8 87 b1 a8 f9 <0f> 0b eb d6 e8 ce 42 f4 f9 e9 33 fd ff ff e8 c4 42 f4 f9 e9 1c fe
RSP: 0018:ffffc90014f3f6e8 EFLAGS: 00010212
RAX: 0000000000010ddb RBX: ffff88801d0b9800 RCX: ffffc900039d5000
RDX: 0000000000040000 RSI: ffffffff87d07ec9 RDI: 0000000000000003
RBP: ffffc90014f3f8e8 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87d07c1b R11: 0000000000000000 R12: 0000000000000007
R13: 0000000000000000 R14: 0000000000000008 R15: ffff88801d0b9800
FS:  00007f16565fe700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f164d37f718 CR3: 000000001e9ec000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 tcp_cong_control net/ipv4/tcp_input.c:3487 [inline]
 tcp_ack+0x40f4/0x5900 net/ipv4/tcp_input.c:3891
 tcp_rcv_established+0x5e8/0x2020 net/ipv4/tcp_input.c:5959
 tcp_v4_do_rcv+0x66c/0x980 net/ipv4/tcp_ipv4.c:1660
 sk_backlog_rcv include/net/sock.h:1051 [inline]
 __release_sock+0x134/0x3b0 net/core/sock.c:2794
 __sk_flush_backlog+0x22/0x30 net/core/sock.c:2814
 sk_flush_backlog include/net/sock.h:1141 [inline]
 tcp_sendmsg_locked+0x295b/0x2fb0 net/ipv4/tcp.c:1294
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1449
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 __sys_sendto+0x216/0x310 net/socket.c:2040
 __do_sys_sendto net/socket.c:2052 [inline]
 __se_sys_sendto net/socket.c:2048 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2048
 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: 0033:0x7f16576890e9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f16565fe168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f165779bf60 RCX: 00007f16576890e9
RDX: ffffffffffffff94 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 00007f16576e308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1657ccfb1f R14: 00007f16565fe300 R15: 0000000000022000
 </TASK>