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BUG: KMSAN: uninit-value in __neigh_create+0x279e/0x2c10 net/core/neighbour.c:563
CPU: 1 PID: 14170 Comm: syz-executor0 Not tainted 4.20.0-rc3+ #104
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x32d/0x480 lib/dump_stack.c:113
 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:683
 __msan_warning+0x76/0xc0 mm/kmsan/kmsan_instr.c:316
 __neigh_create+0x279e/0x2c10 net/core/neighbour.c:563
 ip_finish_output2+0xa1c/0x1560 net/ipv4/ip_output.c:224
 ip_finish_output+0xd93/0x10f0 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip_output+0x55c/0x630 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 ip_local_out+0x164/0x1d0 net/ipv4/ip_output.c:124
 iptunnel_xmit+0x812/0xd30 net/ipv4/ip_tunnel_core.c:91
 ip_tunnel_xmit+0x3943/0x3d90 net/ipv4/ip_tunnel.c:787
 __gre_xmit net/ipv4/ip_gre.c:451 [inline]
 ipgre_xmit+0xef7/0x1000 net/ipv4/ip_gre.c:705
 __netdev_start_xmit include/linux/netdevice.h:4356 [inline]
 netdev_start_xmit include/linux/netdevice.h:4365 [inline]
 xmit_one net/core/dev.c:3252 [inline]
 dev_hard_start_xmit+0x6dc/0xde0 net/core/dev.c:3268
 __dev_queue_xmit+0x2d9e/0x3e00 net/core/dev.c:3838
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3871
 packet_snd net/packet/af_packet.c:2928 [inline]
 packet_sendmsg+0x797f/0x9180 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xdbc/0x11d0 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x305/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457569
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb90333cc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000020001540 RDI: 0000000000000004
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb90333d6d4
R13: 00000000004c3f7d R14: 00000000004d65d8 R15: 00000000ffffffff

Uninit was created at:
No stack
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