BUG: please report to dccp@vger.kernel.org => prev = 5, last = 5 at net/dccp/ccids/lib/packet_history.c:414/tfrc_rx_hist_sample_rtt() CPU: 0 PID: 15 Comm: ksoftirqd/0 Not tainted 5.18.0-rc4-syzkaller-00197-g2d0de93ca251 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 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+0x130/0x1a0 net/dccp/ipv4.c:667 sk_backlog_rcv include/net/sock.h:1051 [inline] __sk_receive_skb+0x299/0x820 net/core/sock.c:542 dccp_v4_rcv+0xfc0/0x1bb0 net/dccp/ipv4.c:890 ip_protocol_deliver_rcu+0xa3/0xb30 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2ee/0x4c0 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x1b3/0x200 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish+0x1cb/0x2f0 net/ipv4/ip_input.c:437 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0xaa/0xd0 net/ipv4/ip_input.c:556 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5405 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5519 process_backlog+0x3a0/0x7c0 net/core/dev.c:5847 __napi_poll+0xb3/0x6e0 net/core/dev.c:6413 napi_poll net/core/dev.c:6480 [inline] net_rx_action+0x8ec/0xc60 net/core/dev.c:6567 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 run_ksoftirqd kernel/softirq.c:921 [inline] run_ksoftirqd+0x2d/0x60 kernel/softirq.c:913 smpboot_thread_fn+0x645/0x9c0 kernel/smpboot.c:164 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298