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: 16127 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 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 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5283 Code: c9 50 e8 19 ae 0b 00 48 83 c4 08 4c 89 f7 e8 1d 38 00 00 0f 1f 44 00 00 4c 89 f7 e8 f0 0d 19 0a e8 8b 39 36 00 fb 48 8b 5d c0 <48> 8d bb f0 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc900037af6c8 EFLAGS: 00000282 RAX: 1b6c9d876c560000 RBX: ffff88802a021e00 RCX: ffffffff944d9603 RDX: dffffc0000000000 RSI: ffffffff8baac1e0 RDI: ffffffff8bfed360 RBP: ffffc900037af710 R08: ffffffff8f872cef R09: 1ffffffff1f0e59d R10: dffffc0000000000 R11: fffffbfff1f0e59e R12: 1ffff11017287e17 R13: dffffc0000000000 R14: ffff8880b943e340 R15: ffff8880b943f0b8 context_switch kernel/sched/core.c:5412 [inline] __schedule+0x17db/0x4a20 kernel/sched/core.c:6736 preempt_schedule_common+0x84/0xd0 kernel/sched/core.c:6915 preempt_schedule+0xe1/0xf0 kernel/sched/core.c:6939 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:12 class_preempt_destructor include/linux/preempt.h:480 [inline] try_to_wake_up+0x9a8/0x1470 kernel/sched/core.c:4385 wake_up_process kernel/sched/core.c:4510 [inline] wake_up_q+0xc8/0x120 kernel/sched/core.c:1029 futex_wake+0x523/0x5c0 kernel/futex/waitwake.c:199 do_futex+0x392/0x560 kernel/futex/syscalls.c:107 __do_sys_futex kernel/futex/syscalls.c:179 [inline] __se_sys_futex+0x3f9/0x480 kernel/futex/syscalls.c:160 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f1eefa7de69 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f1eefccfb28 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f1eefa7de69 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f1eefbabf88 RBP: 0000000000000048 R08: 00007f1eefbabf8c R09: 00007f1eefbabf8c R10: 00007f1eef6005f8 R11: 0000000000000246 R12: 00007f1eefbabf80 R13: 0000000000000e1f R14: 0000000000000000 R15: 00007f1eefbabf80 ---------------- Code disassembly (best guess): 0: c9 leave 1: 50 push %rax 2: e8 19 ae 0b 00 call 0xbae20 7: 48 83 c4 08 add $0x8,%rsp b: 4c 89 f7 mov %r14,%rdi e: e8 1d 38 00 00 call 0x3830 13: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 18: 4c 89 f7 mov %r14,%rdi 1b: e8 f0 0d 19 0a call 0xa190e10 20: e8 8b 39 36 00 call 0x3639b0 25: fb sti 26: 48 8b 5d c0 mov -0x40(%rbp),%rbx * 2a: 48 8d bb f0 15 00 00 lea 0x15f0(%rbx),%rdi <-- trapping instruction 31: 48 89 f8 mov %rdi,%rax 34: 48 c1 e8 03 shr $0x3,%rax 38: 49 rex.WB 39: be 00 00 00 00 mov $0x0,%esi 3e: 00 fc add %bh,%ah