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: 1603 Comm: kworker/u4:5 Not tainted 6.1.65-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: bat_events batadv_nc_worker Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 tfrc_rx_hist_sample_rtt+0x34c/0x444 net/dccp/ccids/lib/packet_history.c:414 ccid3_hc_rx_packet_recv+0x554/0xc98 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+0x1ac/0x2d8 net/dccp/input.c:374 dccp_v4_do_rcv+0xe8/0x1d4 net/dccp/ipv4.c:674 sk_backlog_rcv include/net/sock.h:1117 [inline] __sk_receive_skb+0x3f8/0x900 net/core/sock.c:567 dccp_v4_rcv+0xf2c/0x1564 net/dccp/ipv4.c:897 ip_protocol_deliver_rcu+0x340/0x764 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x23c/0x46c net/ipv4/ip_input.c:233 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:302 ip_local_deliver+0x11c/0x190 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:454 [inline] ip_rcv_finish+0x224/0x250 net/ipv4/ip_input.c:449 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:302 ip_rcv+0x78/0x98 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5525 [inline] __netif_receive_skb+0x18c/0x400 net/core/dev.c:5639 process_backlog+0x410/0x784 net/core/dev.c:5967 __napi_poll+0xb4/0x3f0 net/core/dev.c:6534 napi_poll net/core/dev.c:6601 [inline] net_rx_action+0x5cc/0xd3c net/core/dev.c:6712 __do_softirq+0x314/0xe38 kernel/softirq.c:571 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:79 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:893 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:84 invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0x264/0x4d4 kernel/softirq.c:650 irq_exit_rcu+0x14/0x84 kernel/softirq.c:662 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline] el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:486 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline] lock_release+0x528/0xa50 kernel/locking/lockdep.c:5685 rcu_lock_release+0x2c/0x38 include/linux/rcupdate.h:311 rcu_read_unlock include/linux/rcupdate.h:780 [inline] batadv_nc_process_nc_paths+0x290/0x324 net/batman-adv/network-coding.c:699 batadv_nc_worker+0x3c4/0x580 net/batman-adv/network-coding.c:728 process_one_work+0x7ac/0x1404 kernel/workqueue.c:2292 worker_thread+0x8e4/0xfec kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864 ccid3_first_li: No RTT estimate available, using fallback RTT