BUG: stored value of X_recv is zero at net/dccp/ccids/ccid3.c:691/ccid3_first_li() CPU: 1 PID: 21448 Comm: syz-executor.4 Not tainted 6.7.0-rc4-syzkaller-00039-g9ace34a8e446 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x125/0x1b0 lib/dump_stack.c:106 ccid3_first_li+0x2f8/0x500 net/dccp/ccids/ccid3.c:691 tfrc_lh_interval_add+0x610/0x8e0 net/dccp/ccids/lib/loss_interval.c:157 tfrc_rx_handle_loss+0xe04/0x20a0 net/dccp/ccids/lib/packet_history.c:328 ccid3_hc_rx_packet_recv+0x372/0xf50 net/dccp/ccids/ccid3.c:744 ccid_hc_rx_packet_recv net/dccp/ccid.h:182 [inline] dccp_deliver_input_to_ccids+0xe3/0x260 net/dccp/input.c:176 dccp_rcv_established net/dccp/input.c:374 [inline] dccp_rcv_established+0x106/0x160 net/dccp/input.c:364 dccp_v4_do_rcv+0x169/0x1b0 net/dccp/ipv4.c:675 sk_backlog_rcv include/net/sock.h:1121 [inline] __sk_receive_skb+0x2af/0x840 net/core/sock.c:571 dccp_v4_rcv+0x128a/0x1980 net/dccp/ipv4.c:898 ip_protocol_deliver_rcu+0x9f/0x480 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2e4/0x510 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ip_local_deliver+0x18e/0x1f0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish+0x1c4/0x2f0 net/ipv4/ip_input.c:449 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ip_rcv+0xaf/0xd0 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core+0x115/0x180 net/core/dev.c:5529 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5643 process_backlog+0x101/0x6b0 net/core/dev.c:5971 __napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6533 napi_poll net/core/dev.c:6602 [inline] net_rx_action+0x956/0xe90 net/core/dev.c:6735 __do_softirq+0x21a/0x8de kernel/softirq.c:553 do_softirq kernel/softirq.c:454 [inline] do_softirq+0xaa/0xe0 kernel/softirq.c:441 __local_bh_enable_ip+0xfc/0x120 kernel/softirq.c:381 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:817 [inline] __dev_queue_xmit+0x87c/0x3d60 net/core/dev.c:4373 dev_queue_xmit include/linux/netdevice.h:3134 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0x16a4/0x2550 net/ipv4/ip_output.c:235 __ip_finish_output net/ipv4/ip_output.c:313 [inline] __ip_finish_output+0x38b/0x650 net/ipv4/ip_output.c:295 ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip_output+0x13b/0x2a0 net/ipv4/ip_output.c:433 dst_output include/net/dst.h:451 [inline] ip_local_out net/ipv4/ip_output.c:129 [inline] __ip_queue_xmit+0x7cb/0x1a50 net/ipv4/ip_output.c:535 dccp_transmit_skb+0xd21/0x1610 net/dccp/output.c:138 dccp_send_sync+0x1c2/0x270 net/dccp/output.c:666 dccp_rcv_state_process+0x998/0x1510 net/dccp/input.c:703 dccp_v4_do_rcv+0x117/0x1b0 net/dccp/ipv4.c:704 sk_backlog_rcv include/net/sock.h:1121 [inline] __release_sock+0x132/0x3b0 net/core/sock.c:2968 release_sock+0x5a/0x1f0 net/core/sock.c:3534 dccp_sendmsg+0x40f/0xcc0 net/dccp/proto.c:803 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:847 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0xd5/0x180 net/socket.c:745 __sys_sendto+0x255/0x340 net/socket.c:2190 __do_sys_sendto net/socket.c:2202 [inline] __se_sys_sendto net/socket.c:2198 [inline] __x64_sys_sendto+0xe0/0x1b0 net/socket.c:2198 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f05baa7cba9 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:00007f05bb6fa0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f05bab9bf80 RCX: 00007f05baa7cba9 RDX: 000000000000ffc3 RSI: 0000000020000180 RDI: 0000000000000004 RBP: 00007f05baac847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f05bab9bf80 R15: 00007ffd1c7e1498