BUG: please report to dccp@vger.kernel.org => prev = 0, last = 0 at net/dccp/ccids/lib/packet_history.c:417/tfrc_rx_hist_sample_rtt() CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 6.8.0-syzkaller-05204-g237bb5f7f7f5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 tfrc_rx_hist_sample_rtt+0x397/0x4b0 net/dccp/ccids/lib/packet_history.c:414 ccid3_hc_rx_packet_recv+0x69d/0xe60 net/dccp/ccids/ccid3.c:760 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline] dccp_deliver_input_to_ccids net/dccp/input.c:176 [inline] dccp_rcv_established+0x1bb/0x320 net/dccp/input.c:374 dccp_v4_do_rcv+0xff/0x1f0 net/dccp/ipv4.c:675 sk_backlog_rcv include/net/sock.h:1106 [inline] __sk_receive_skb+0x823/0x8a0 net/core/sock.c:569 ip_protocol_deliver_rcu+0x2e0/0x430 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x33f/0x5f0 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5538 [inline] __netif_receive_skb+0x2bf/0x6a0 net/core/dev.c:5652 process_backlog+0x39d/0x7a0 net/core/dev.c:5981 __napi_poll+0xcb/0x490 net/core/dev.c:6632 napi_poll net/core/dev.c:6701 [inline] net_rx_action+0x7bb/0x1090 net/core/dev.c:6813 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 run_ksoftirqd+0xc5/0x130 kernel/softirq.c:924 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243