dccp_v4_rcv: dropped packet with invalid checksum
dccp_v4_rcv: dropped packet with invalid checksum
TCP: request_sock_TCP: Possible SYN flooding on port 20014. Sending cookies.  Check SNMP counters.
==================================================================
BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:344 [inline]
BUG: KASAN: slab-out-of-bounds in tcp_v6_syn_recv_sock+0x1612/0x23a0 net/ipv6/tcp_ipv6.c:1076
Write of size 160 at addr ffff8801d822e9e0 by task syz-executor3/19849

CPU: 0 PID: 19849 Comm: syz-executor3 Not tainted 4.15.0-rc8+ #268
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x25b/0x340 mm/kasan/report.c:409
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
 memcpy+0x37/0x50 mm/kasan/kasan.c:303
 memcpy include/linux/string.h:344 [inline]
 tcp_v6_syn_recv_sock+0x1612/0x23a0 net/ipv6/tcp_ipv6.c:1076
 tcp_get_cookie_sock+0x102/0x540 net/ipv4/syncookies.c:213
 cookie_v4_check+0x1a87/0x2920 net/ipv4/syncookies.c:396
 tcp_v4_cookie_check net/ipv4/tcp_ipv4.c:1439 [inline]
 tcp_v4_do_rcv+0x6e9/0x7d0 net/ipv4/tcp_ipv4.c:1476
 tcp_v4_rcv+0x275f/0x2eb0 net/ipv4/tcp_ipv4.c:1735
 ip_local_deliver_finish+0x2f1/0xc50 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:466 [inline]
 ip_rcv_finish+0x959/0x1e30 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_rcv+0xc5a/0x1840 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a41/0x3460 net/core/dev.c:4473
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4538
 process_backlog+0x203/0x740 net/core/dev.c:5217
 napi_poll net/core/dev.c:5615 [inline]
 net_rx_action+0x792/0x1910 net/core/dev.c:5681
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1150
 </IRQ>
 do_softirq.part.19+0x14d/0x190 kernel/softirq.c:329
 do_softirq kernel/softirq.c:177 [inline]
 __local_bh_enable_ip+0x1ee/0x230 kernel/softirq.c:182
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:727 [inline]
 ip_finish_output2+0x96e/0x1560 net/ipv4/ip_output.c:231
 ip_finish_output+0x864/0xd10 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:239 [inline]
 ip_output+0x1d2/0x860 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:460 [inline]
 ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x8c6/0x18e0 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x1b1b/0x38c0 net/ipv4/tcp_output.c:1176
 tcp_send_ack.part.41+0x389/0x610 net/ipv4/tcp_output.c:3617
 tcp_send_ack+0x49/0x60 net/ipv4/tcp_output.c:3587
 tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:5707 [inline]
 tcp_rcv_state_process+0x3d0f/0x4830 net/ipv4/tcp_input.c:5842
 tcp_v4_do_rcv+0x55c/0x7d0 net/ipv4/tcp_ipv4.c:1490
 sk_backlog_rcv include/net/sock.h:907 [inline]
 __release_sock+0x124/0x360 net/core/sock.c:2264
 release_sock+0xa4/0x2a0 net/core/sock.c:2779
 tcp_sendmsg+0x3a/0x50 net/ipv4/tcp.c:1462
 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:763
 sock_sendmsg_nosec net/socket.c:638 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:648
 SYSC_sendto+0x361/0x5c0 net/socket.c:1729
 SyS_sendto+0x40/0x50 net/socket.c:1697
 entry_SYSCALL_64_fastpath+0x29/0xa0
RIP: 0033:0x452e99
RSP: 002b:00007f3e9773fc58 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452e99
RDX: 0000000000000000 RSI: 0000000020d44000 RDI: 0000000000000016
RBP: 00000000000003a4 R08: 00000000200b0000 R09: 0000000000000010
R10: 0000000020008045 R11: 0000000000000212 R12: 00000000006f3800
R13: 00000000ffffffff R14: 00007f3e977406d4 R15: 0000000000000000

Allocated by task 19849:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3544
 sk_prot_alloc+0x65/0x2a0 net/core/sock.c:1463
 sk_clone_lock+0x152/0x1570 net/core/sock.c:1649
 inet_csk_clone_lock+0x92/0x4f0 net/ipv4/inet_connection_sock.c:781
 tcp_create_openreq_child+0x9b/0x1b70 net/ipv4/tcp_minisocks.c:449
 tcp_v4_syn_recv_sock+0x119/0x1270 net/ipv4/tcp_ipv4.c:1350
 tcp_v6_syn_recv_sock+0x1574/0x23a0 net/ipv6/tcp_ipv6.c:1063
 tcp_get_cookie_sock+0x102/0x540 net/ipv4/syncookies.c:213
 cookie_v4_check+0x1a87/0x2920 net/ipv4/syncookies.c:396
 tcp_v4_cookie_check net/ipv4/tcp_ipv4.c:1439 [inline]
 tcp_v4_do_rcv+0x6e9/0x7d0 net/ipv4/tcp_ipv4.c:1476
 tcp_v4_rcv+0x275f/0x2eb0 net/ipv4/tcp_ipv4.c:1735
 ip_local_deliver_finish+0x2f1/0xc50 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_local_deliver+0x1ce/0x6e0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:466 [inline]
 ip_rcv_finish+0x959/0x1e30 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:250 [inline]
 ip_rcv+0xc5a/0x1840 net/ipv4/ip_input.c:493
 __netif_receive_skb_core+0x1a41/0x3460 net/core/dev.c:4473
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4538
 process_backlog+0x203/0x740 net/core/dev.c:5217
 napi_poll net/core/dev.c:5615 [inline]
 net_rx_action+0x792/0x1910 net/core/dev.c:5681
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8801d822e000
 which belongs to the cache TCP of size 2528
The buggy address is located 0 bytes to the right of
 2528-byte region [ffff8801d822e000, ffff8801d822e9e0)
The buggy address belongs to the page:
page:ffffea0007608b80 count:1 mapcount:0 mapping:ffff8801d822e000 index:0xffff8801d822fffd compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801d822e000 ffff8801d822fffd 0000000100000003
raw: ffffea0006f4f0a0 ffffea00072392a0 ffff8801d83281c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d822e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801d822e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8801d822e980: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc
                                                       ^
 ffff8801d822ea00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801d822ea80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================