BUG: please report to dccp@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:414/tfrc_rx_hist_sample_rtt()
CPU: 0 PID: 16280 Comm: syz-executor.4 Not tainted 5.11.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 tfrc_rx_hist_sample_rtt+0x4a5/0x4b0 net/dccp/ccids/lib/packet_history.c:414
 ccid3_hc_rx_packet_recv+0x5b8/0xe90 net/dccp/ccids/ccid3.c:760
 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline]
 dccp_deliver_input_to_ccids+0xe1/0x260 net/dccp/input.c:176
 dccp_rcv_established net/dccp/input.c:374 [inline]
 dccp_rcv_established+0x107/0x160 net/dccp/input.c:364
 dccp_v4_do_rcv+0x130/0x190 net/dccp/ipv4.c:657
 sk_backlog_rcv include/net/sock.h:1016 [inline]
 __sk_receive_skb+0x29d/0x830 net/core/sock.c:509
 dccp_v4_rcv+0xe8b/0x1850 net/dccp/ipv4.c:880
 ip_protocol_deliver_rcu+0x5c/0x8a0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish+0x20a/0x370 net/ipv4/ip_input.c:231
 NF_HOOK include/linux/netfilter.h:301 [inline]
 NF_HOOK include/linux/netfilter.h:295 [inline]
 ip_local_deliver+0x1b3/0x200 net/ipv4/ip_input.c:252
 dst_input include/net/dst.h:447 [inline]
 ip_rcv_finish+0x1da/0x2f0 net/ipv4/ip_input.c:428
 NF_HOOK include/linux/netfilter.h:301 [inline]
 NF_HOOK include/linux/netfilter.h:295 [inline]
 ip_rcv+0xaa/0xd0 net/ipv4/ip_input.c:539
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5332
 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5446
 process_backlog+0x232/0x6c0 net/core/dev.c:6325
 napi_poll net/core/dev.c:6803 [inline]
 net_rx_action+0x461/0xe10 net/core/dev.c:6886
 __do_softirq+0x2bc/0xa29 kernel/softirq.c:343
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:246 [inline]
 do_softirq+0xb5/0xe0 kernel/softirq.c:233
 __local_bh_enable_ip+0xf4/0x110 kernel/softirq.c:196
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:737 [inline]
 ip_finish_output2+0x88b/0x21b0 net/ipv4/ip_output.c:231
 __ip_finish_output net/ipv4/ip_output.c:308 [inline]
 __ip_finish_output+0x396/0x640 net/ipv4/ip_output.c:290
 ip_finish_output+0x35/0x200 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:290 [inline]
 ip_output+0x196/0x310 net/ipv4/ip_output.c:432
 dst_output include/net/dst.h:441 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0x8e9/0x1a00 net/ipv4/ip_output.c:532
 dccp_transmit_skb+0x973/0x12c0 net/dccp/output.c:138
 dccp_xmit_packet+0x270/0x750 net/dccp/output.c:281
 dccp_write_xmit+0x16d/0x1d0 net/dccp/output.c:366
 dccp_sendmsg+0x920/0xc90 net/dccp/proto.c:794
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:817
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:672
 ____sys_sendmsg+0x331/0x810 net/socket.c:2345
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2399
 __sys_sendmmsg+0x195/0x470 net/socket.c:2489
 __do_sys_sendmmsg net/socket.c:2518 [inline]
 __se_sys_sendmmsg net/socket.c:2515 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2515
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e219
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f7648872c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045e219
RDX: 0000000004000017 RSI: 0000000020001e80 RDI: 0000000000000004
RBP: 000000000119bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007ffdfe8aaa1f R14: 00007f76488739c0 R15: 000000000119bf8c