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 UID: 0 PID: 6869 Comm: syz-executor.0 Not tainted 6.13.0-rc7-syzkaller-00071-g1950a0af2d55 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 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+0xe8/0x1d8 net/dccp/ipv4.c:680 sk_backlog_rcv include/net/sock.h:1121 [inline] __sk_receive_skb+0x3e8/0x8c0 net/core/sock.c:568 dccp_v4_rcv+0xf68/0x146c net/dccp/ipv4.c:903 ip_protocol_deliver_rcu+0x1f8/0x484 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x284/0x4f0 net/ipv4/ip_input.c:233 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 ip_local_deliver+0x120/0x194 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_rcv_finish+0x220/0x24c net/ipv4/ip_input.c:447 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 ip_rcv+0x7c/0x9c net/ipv4/ip_input.c:567 __netif_receive_skb_one_core net/core/dev.c:5704 [inline] __netif_receive_skb+0x18c/0x3c8 net/core/dev.c:5817 process_backlog+0x640/0x123c net/core/dev.c:6149 __napi_poll+0xb4/0x3fc net/core/dev.c:6902 napi_poll net/core/dev.c:6971 [inline] net_rx_action+0x6a8/0xf4c net/core/dev.c:7093 handle_softirqs+0x320/0xd34 kernel/softirq.c:561 __do_softirq+0x14/0x20 kernel/softirq.c:595 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:891 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86 invoke_softirq kernel/softirq.c:442 [inline] __irq_exit_rcu+0x1d8/0x544 kernel/softirq.c:662 irq_exit_rcu+0x14/0x84 kernel/softirq.c:678 __el1_irq arch/arm64/kernel/entry-common.c:561 [inline] el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:575 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:580 el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:596 __daif_local_irq_enable arch/arm64/include/asm/irqflags.h:26 [inline] (P) arch_local_irq_enable arch/arm64/include/asm/irqflags.h:48 [inline] (P) __local_bh_enable_ip+0x228/0x44c kernel/softirq.c:394 (P) __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] lock_sock_nested+0xcc/0x11c net/core/sock.c:3632 lock_sock include/net/sock.h:1623 [inline] dccp_sendmsg+0x370/0xaf8 net/dccp/proto.c:765 inet_sendmsg+0x15c/0x290 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] ____sys_sendmsg+0x56c/0x840 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmmsg+0x2fc/0x76c net/socket.c:2726 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2750 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Negotiation of local Allow Short Seqnos failed in state CHANGING at net/dccp/feat.c:1541/dccp_feat_activate_values() BUG: stored value of X_recv is zero at net/dccp/ccids/ccid3.c:691/ccid3_first_li() CPU: 0 UID: 0 PID: 7096 Comm: syz-executor.0 Not tainted 6.13.0-rc7-syzkaller-00071-g1950a0af2d55 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 ccid3_first_li+0x354/0x3c0 net/dccp/ccids/ccid3.c:691 tfrc_lh_interval_add+0x4a4/0x694 net/dccp/ccids/lib/loss_interval.c:157 tfrc_rx_handle_loss+0x564/0x14e0 net/dccp/ccids/lib/packet_history.c:328 ccid3_hc_rx_packet_recv+0x2bc/0xc98 net/dccp/ccids/ccid3.c:744 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+0xe8/0x1d8 net/dccp/ipv4.c:680 sk_backlog_rcv include/net/sock.h:1121 [inline] __sk_receive_skb+0x3e8/0x8c0 net/core/sock.c:568 dccp_v4_rcv+0xf68/0x146c net/dccp/ipv4.c:903 ip_protocol_deliver_rcu+0x1f8/0x484 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x284/0x4f0 net/ipv4/ip_input.c:233 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 ip_local_deliver+0x120/0x194 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_rcv_finish+0x220/0x24c net/ipv4/ip_input.c:447 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 ip_rcv+0x7c/0x9c net/ipv4/ip_input.c:567 __netif_receive_skb_one_core net/core/dev.c:5704 [inline] __netif_receive_skb+0x18c/0x3c8 net/core/dev.c:5817 process_backlog+0x640/0x123c net/core/dev.c:6149 __napi_poll+0xb4/0x3fc net/core/dev.c:6902 napi_poll net/core/dev.c:6971 [inline] net_rx_action+0x6a8/0xf4c net/core/dev.c:7093 handle_softirqs+0x320/0xd34 kernel/softirq.c:561 __do_softirq+0x14/0x20 kernel/softirq.c:595 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:891 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86 do_softirq+0x90/0xf8 kernel/softirq.c:462 __local_bh_enable_ip+0x288/0x44c kernel/softirq.c:389 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x3c/0x4c kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] release_sock+0x154/0x1b8 net/core/sock.c:3649 dccp_sendmsg+0x460/0xaf8 net/dccp/proto.c:803 inet_sendmsg+0x15c/0x290 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg net/socket.c:726 [inline] ____sys_sendmsg+0x56c/0x840 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmmsg+0x2fc/0x76c net/socket.c:2726 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2750 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Negotiation of local Allow Short Seqnos failed in state CHANGING at net/dccp/feat.c:1541/dccp_feat_activate_values()