dccp_xmit_packet: Payload too large (65423) for featneg. ================================================================== BUG: KMSAN: uninit-value in ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:66 [inline] BUG: KMSAN: uninit-value in iptable_mangle_hook+0x5e5/0x720 net/ipv4/netfilter/iptable_mangle.c:84 CPU: 1 PID: 6750 Comm: syz-executor3 Not tainted 4.16.0+ #87 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:66 [inline] iptable_mangle_hook+0x5e5/0x720 net/ipv4/netfilter/iptable_mangle.c:84 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0x158/0x3d0 net/netfilter/core.c:483 nf_hook include/linux/netfilter.h:243 [inline] __ip_local_out+0x6d5/0x7e0 net/ipv4/ip_output.c:113 ip_local_out net/ipv4/ip_output.c:122 [inline] ip_queue_xmit+0x1958/0x1d10 net/ipv4/ip_output.c:504 dccp_transmit_skb+0x15eb/0x1900 net/dccp/output.c:142 dccp_send_ack+0x2de/0x560 net/dccp/output.c:595 ccid2_hc_rx_packet_recv+0x229/0x270 net/dccp/ccids/ccid2.c:766 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline] dccp_deliver_input_to_ccids net/dccp/input.c:180 [inline] dccp_rcv_established+0x3d9/0x620 net/dccp/input.c:378 dccp_v4_do_rcv+0x19a/0x340 net/dccp/ipv4.c:653 sk_backlog_rcv include/net/sock.h:908 [inline] __sk_receive_skb+0x60e/0xf20 net/core/sock.c:513 dccp_v4_rcv+0x25e5/0x2750 net/dccp/ipv4.c:874 ip_local_deliver_finish+0x874/0xec0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x118f/0x16d0 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562 __netif_receive_skb net/core/dev.c:4627 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771 __do_softirq+0x56d/0x93d kernel/softirq.c:285 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1040 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x114/0x140 kernel/softirq.c:182 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:726 [inline] ip_finish_output2+0x135a/0x1470 net/ipv4/ip_output.c:231 ip_finish_output+0xcb2/0xff0 net/ipv4/ip_output.c:317 NF_HOOK_COND include/linux/netfilter.h:277 [inline] ip_output+0x505/0x5d0 net/ipv4/ip_output.c:405 dst_output include/net/dst.h:443 [inline] ip_local_out net/ipv4/ip_output.c:124 [inline] ip_queue_xmit+0x1a1e/0x1d10 net/ipv4/ip_output.c:504 dccp_transmit_skb+0x15eb/0x1900 net/dccp/output.c:142 dccp_xmit_packet+0x817/0x9e0 net/dccp/output.c:281 dccp_write_xmit+0x20f/0x480 net/dccp/output.c:363 dccp_sendmsg+0x12ca/0x12d0 net/dccp/proto.c:818 inet_sendmsg+0x48d/0x740 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] SYSC_sendto+0x6c3/0x7e0 net/socket.c:1747 SyS_sendto+0x8a/0xb0 net/socket.c:1715 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x455979 RSP: 002b:00007f9a47d59c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f9a47d5a6d4 RCX: 0000000000455979 RDX: 000000000000ffc3 RSI: 0000000020494f01 RDI: 0000000000000014 RBP: 000000000072bea0 R08: 0000000020198ff0 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000545 R14: 00000000006fbf18 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:528 ip_queue_xmit+0x1b47/0x1d10 net/ipv4/ip_output.c:502 dccp_transmit_skb+0x15eb/0x1900 net/dccp/output.c:142 dccp_send_ack+0x2de/0x560 net/dccp/output.c:595 ccid2_hc_rx_packet_recv+0x229/0x270 net/dccp/ccids/ccid2.c:766 ccid_hc_rx_packet_recv net/dccp/ccid.h:185 [inline] dccp_deliver_input_to_ccids net/dccp/input.c:180 [inline] dccp_rcv_established+0x3d9/0x620 net/dccp/input.c:378 dccp_v4_do_rcv+0x19a/0x340 net/dccp/ipv4.c:653 sk_backlog_rcv include/net/sock.h:908 [inline] __sk_receive_skb+0x60e/0xf20 net/core/sock.c:513 dccp_v4_rcv+0x25e5/0x2750 net/dccp/ipv4.c:874 ip_local_deliver_finish+0x874/0xec0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x118f/0x16d0 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562 __netif_receive_skb net/core/dev.c:4627 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771 __do_softirq+0x56d/0x93d kernel/softirq.c:285 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_save_stack mm/kmsan/kmsan.c:293 [inline] kmsan_internal_chain_origin+0x12b/0x210 mm/kmsan/kmsan.c:684 __msan_chain_origin+0x69/0xc0 mm/kmsan/kmsan_instr.c:528 inet_csk_clone_lock+0x503/0x580 net/ipv4/inet_connection_sock.c:797 dccp_create_openreq_child+0x7f/0x890 net/dccp/minisocks.c:92 dccp_v4_request_recv_sock+0x22c/0xe90 net/dccp/ipv4.c:408 dccp_v6_request_recv_sock+0x2a3/0x2090 net/dccp/ipv6.c:414 dccp_check_req+0x7b9/0x8f0 net/dccp/minisocks.c:197 dccp_v4_rcv+0x12c1/0x2750 net/dccp/ipv4.c:840 ip_local_deliver_finish+0x874/0xec0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x118f/0x16d0 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562 __netif_receive_skb net/core/dev.c:4627 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771 __do_softirq+0x56d/0x93d kernel/softirq.c:285 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmem_cache_alloc+0xaab/0xb90 mm/slub.c:2756 reqsk_alloc include/net/request_sock.h:88 [inline] inet_reqsk_alloc+0xc4/0x7f0 net/ipv4/tcp_input.c:6145 dccp_v4_conn_request+0x5cc/0x1770 net/dccp/ipv4.c:600 dccp_v6_conn_request+0x299/0x18f0 net/dccp/ipv6.c:317 dccp_rcv_state_process+0x2ea/0x2410 net/dccp/input.c:612 dccp_v4_do_rcv+0x229/0x340 net/dccp/ipv4.c:682 dccp_v6_do_rcv+0x16d/0x1290 net/dccp/ipv6.c:578 sk_backlog_rcv include/net/sock.h:908 [inline] __sk_receive_skb+0x60e/0xf20 net/core/sock.c:513 dccp_v4_rcv+0x25e5/0x2750 net/dccp/ipv4.c:874 ip_local_deliver_finish+0x874/0xec0 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:288 [inline] ip_local_deliver+0x43c/0x4e0 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:449 [inline] ip_rcv_finish+0xa36/0x1d00 net/ipv4/ip_input.c:397 NF_HOOK include/linux/netfilter.h:288 [inline] ip_rcv+0x118f/0x16d0 net/ipv4/ip_input.c:493 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562 __netif_receive_skb net/core/dev.c:4627 [inline] process_backlog+0x62d/0xe20 net/core/dev.c:5307 napi_poll net/core/dev.c:5705 [inline] net_rx_action+0x7c1/0x1a70 net/core/dev.c:5771 __do_softirq+0x56d/0x93d kernel/softirq.c:285 ==================================================================