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: 1 PID: 6442 Comm: syz-executor.0 Not tainted 6.7.0-rc8-syzkaller-00101-g0802e17d9aca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 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:675 sk_backlog_rcv include/net/sock.h:1121 [inline] __sk_receive_skb+0x3e4/0x8ec net/core/sock.c:571 dccp_v4_rcv+0xf5c/0x14e8 net/dccp/ipv4.c:898 ip_protocol_deliver_rcu+0x1f8/0x47c 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:314 ip_local_deliver+0x120/0x194 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish+0x224/0x250 net/ipv4/ip_input.c:449 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 ip_rcv+0x7c/0x9c net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5532 [inline] __netif_receive_skb+0x18c/0x400 net/core/dev.c:5646 process_backlog+0x3c0/0x70c net/core/dev.c:5974 __napi_poll+0xb4/0x650 net/core/dev.c:6536 napi_poll net/core/dev.c:6605 [inline] net_rx_action+0x5e4/0xdc4 net/core/dev.c:6738 __do_softirq+0x2d8/0xce4 kernel/softirq.c:553 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:886 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86 invoke_softirq kernel/softirq.c:434 [inline] __irq_exit_rcu+0x1d8/0x434 kernel/softirq.c:632 irq_exit_rcu+0x14/0x84 kernel/softirq.c:644 __el1_irq arch/arm64/kernel/entry-common.c:503 [inline] el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:517 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:522 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:591 __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:176 [inline] arch_local_irq_restore arch/arm64/include/asm/irqflags.h:196 [inline] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] _raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] add_wait_queue+0x15c/0x188 kernel/sched/wait.c:24 do_wait+0x178/0x550 kernel/exit.c:1622 kernel_wait4+0x24c/0x3d8 kernel/exit.c:1785 __do_sys_wait4 kernel/exit.c:1813 [inline] __se_sys_wait4 kernel/exit.c:1809 [inline] __arm64_sys_wait4+0x11c/0x2a0 kernel/exit.c:1809 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 Negotiation of local Allow Short Seqnos failed in state CHANGING at net/dccp/feat.c:1537/dccp_feat_activate_values() Negotiation of local Allow Short Seqnos failed in state CHANGING at net/dccp/feat.c:1537/dccp_feat_activate_values() BUG: stored value of X_recv is zero at net/dccp/ccids/ccid3.c:691/ccid3_first_li() CPU: 1 PID: 7065 Comm: syz-executor.0 Not tainted 6.7.0-rc8-syzkaller-00101-g0802e17d9aca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 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+0xe8/0x1d4 net/dccp/ipv4.c:675 sk_backlog_rcv include/net/sock.h:1121 [inline] __sk_receive_skb+0x3e4/0x8ec net/core/sock.c:571 dccp_v4_rcv+0xf5c/0x14e8 net/dccp/ipv4.c:898 ip_protocol_deliver_rcu+0x1f8/0x47c 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:314 ip_local_deliver+0x120/0x194 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish+0x224/0x250 net/ipv4/ip_input.c:449 NF_HOOK+0x328/0x3d4 include/linux/netfilter.h:314 ip_rcv+0x7c/0x9c net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5532 [inline] __netif_receive_skb+0x18c/0x400 net/core/dev.c:5646 process_backlog+0x3c0/0x70c net/core/dev.c:5974 __napi_poll+0xb4/0x650 net/core/dev.c:6536 napi_poll net/core/dev.c:6605 [inline] net_rx_action+0x5e4/0xdc4 net/core/dev.c:6738 __do_softirq+0x2d8/0xce4 kernel/softirq.c:553 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:886 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86 do_softirq+0x90/0xf8 kernel/softirq.c:454 __local_bh_enable_ip+0x288/0x44c kernel/softirq.c:381 __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:3543 dccp_sendmsg+0x330/0xae8 net/dccp/proto.c:763 inet_sendmsg+0x15c/0x290 net/ipv4/af_inet.c:847 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x56c/0x840 net/socket.c:2584 ___sys_sendmsg net/socket.c:2638 [inline] __sys_sendmmsg+0x318/0x7d8 net/socket.c:2724 __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:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 Negotiation of local Allow Short Seqnos failed in state CHANGING at net/dccp/feat.c:1537/dccp_feat_activate_values()