TCP: request_sock_subflow_v4: Possible SYN flooding on port [::]:20002. Sending cookies. ===================================================== BUG: KMSAN: uninit-value in mptcp_incoming_options+0xc93/0x3a80 net/mptcp/options.c:1197 mptcp_incoming_options+0xc93/0x3a80 net/mptcp/options.c:1197 tcp_data_queue+0xb4/0x7f20 net/ipv4/tcp_input.c:5141 tcp_rcv_established+0x1132/0x2600 net/ipv4/tcp_input.c:6155 tcp_v4_do_rcv+0x8a8/0xff0 net/ipv4/tcp_ipv4.c:1906 tcp_v4_rcv+0x4ce0/0x51a0 net/ipv4/tcp_ipv4.c:2329 ip_protocol_deliver_rcu+0x264/0x1300 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2b8/0x440 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish net/ipv4/ip_input.c:449 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ip_rcv+0x476/0x770 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5529 [inline] __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5643 process_backlog+0x480/0x8b0 net/core/dev.c:5971 __napi_poll+0xe3/0x970 net/core/dev.c:6533 napi_poll net/core/dev.c:6602 [inline] net_rx_action+0x884/0x16d0 net/core/dev.c:6735 __do_softirq+0x1b7/0x7c3 kernel/softirq.c:553 do_softirq+0x9a/0xf0 kernel/softirq.c:454 __local_bh_enable_ip+0x99/0xa0 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+0x24ff/0x5130 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+0x14be/0x1b40 net/ipv4/ip_output.c:235 __ip_finish_output+0x266/0x720 ip_finish_output+0x4b/0x550 net/ipv4/ip_output.c:323 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip_output+0x15f/0x3e0 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+0x1c02/0x1e00 net/ipv4/ip_output.c:535 ip_queue_xmit+0x60/0x80 net/ipv4/ip_output.c:549 __tcp_transmit_skb+0x3b26/0x4c40 net/ipv4/tcp_output.c:1462 tcp_transmit_skb net/ipv4/tcp_output.c:1480 [inline] tcp_write_xmit+0x3e0f/0x8940 net/ipv4/tcp_output.c:2792 __tcp_push_pending_frames+0xc4/0x380 net/ipv4/tcp_output.c:2977 tcp_push+0x755/0x7a0 net/ipv4/tcp.c:736 mptcp_push_release net/mptcp/protocol.c:1489 [inline] __mptcp_push_pending+0x8bc/0xde0 net/mptcp/protocol.c:1624 mptcp_sendmsg+0x1e90/0x2300 net/mptcp/protocol.c:1890 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:847 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x781/0xa30 net/socket.c:2190 __do_sys_sendto net/socket.c:2202 [inline] __se_sys_sendto net/socket.c:2198 [inline] __x64_sys_sendto+0x125/0x1c0 net/socket.c:2198 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b Uninit was stored to memory at: mptcp_parse_option net/mptcp/options.c:110 [inline] mptcp_get_options+0x2d86/0x2e60 net/mptcp/options.c:396 mptcp_incoming_options+0x124/0x3a80 net/mptcp/options.c:1139 tcp_data_queue+0xb4/0x7f20 net/ipv4/tcp_input.c:5141 tcp_rcv_established+0x1132/0x2600 net/ipv4/tcp_input.c:6155 tcp_v4_do_rcv+0x8a8/0xff0 net/ipv4/tcp_ipv4.c:1906 tcp_v4_rcv+0x4ce0/0x51a0 net/ipv4/tcp_ipv4.c:2329 ip_protocol_deliver_rcu+0x264/0x1300 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2b8/0x440 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x21f/0x490 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:461 [inline] ip_rcv_finish net/ipv4/ip_input.c:449 [inline] NF_HOOK include/linux/netfilter.h:314 [inline] ip_rcv+0x476/0x770 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core net/core/dev.c:5529 [inline] __netif_receive_skb+0x1a6/0x5a0 net/core/dev.c:5643 process_backlog+0x480/0x8b0 net/core/dev.c:5971 __napi_poll+0xe3/0x970 net/core/dev.c:6533 napi_poll net/core/dev.c:6602 [inline] net_rx_action+0x884/0x16d0 net/core/dev.c:6735 __do_softirq+0x1b7/0x7c3 kernel/softirq.c:553 Local variable mp_opt created at: mptcp_incoming_options+0x9b/0x3a80 net/mptcp/options.c:1116 tcp_data_queue+0xb4/0x7f20 net/ipv4/tcp_input.c:5141 CPU: 0 PID: 31680 Comm: syz-executor.1 Not tainted 6.7.0-rc3-syzkaller-00024-g18d46e76d7c2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 =====================================================