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BUG: KMSAN: uninit-value in ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1314 [inline]
BUG: KMSAN: uninit-value in ip6_tnl_start_xmit+0x64e/0x1e20 net/ipv6/ip6_tunnel.c:1397
CPU: 1 PID: 8175 Comm: syz-executor6 Not tainted 4.18.0-rc8+ #34
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
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+0x17c/0x1c0 lib/dump_stack.c:113
 kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:982
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1314 [inline]
 ip6_tnl_start_xmit+0x64e/0x1e20 net/ipv6/ip6_tunnel.c:1397
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 __netdev_start_xmit include/linux/netdevice.h:4148 [inline]
 netdev_start_xmit include/linux/netdevice.h:4157 [inline]
 xmit_one net/core/dev.c:3034 [inline]
 dev_hard_start_xmit+0x5df/0xc20 net/core/dev.c:3050
 __dev_queue_xmit+0x2eea/0x3a70 net/core/dev.c:3569
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3602
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 packet_snd net/packet/af_packet.c:2921 [inline]
 packet_sendmsg+0x7fb5/0x8ae0 net/packet/af_packet.c:2946
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 ___sys_sendmsg+0xe32/0x1250 net/socket.c:2126
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 __sys_sendmsg net/socket.c:2164 [inline]
 __do_sys_sendmsg net/socket.c:2173 [inline]
 __se_sys_sendmsg net/socket.c:2171 [inline]
 __x64_sys_sendmsg+0x32d/0x460 net/socket.c:2171
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
RIP: 0033:0x457089
Code: fd b4 fb 
hid-generic 0000:0000:0081.0001: unknown main item tag 0x0
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 b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 
RSP: 002b:00007f9cfc494c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9cfc4956d4 RCX: 0000000000457089
RDX: 0000000000000000 RSI: 00000000200004c0 RDI: 0000000000000003
RBP: 00000000009300a0 R08: 0000000000000000 R09: 0000000000000000
hid-generic 0000:0000:0081.0001: hidraw0: <UNKNOWN> HID v0.00 Device [syz1] on syz1
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d40c8 R14: 00000000004c8ad1 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:91
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2720 [inline]
 __kmalloc_node_track_caller+0xb4c/0x11d0 mm/slub.c:4353
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2ce/0x9b0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 alloc_skb_with_frags+0x1d0/0xac0 net/core/skbuff.c:5272
 sock_alloc_send_pskb+0xb47/0x1120 net/core/sock.c:2095
 packet_alloc_skb net/packet/af_packet.c:2776 [inline]
 packet_snd net/packet/af_packet.c:2867 [inline]
 packet_sendmsg+0x6480/0x8ae0 net/packet/af_packet.c:2946
 sock_sendmsg_nosec net/socket.c:642 [inline]
 sock_sendmsg net/socket.c:652 [inline]
 ___sys_sendmsg+0xe32/0x1250 net/socket.c:2126
 __sys_sendmsg net/socket.c:2164 [inline]
 __do_sys_sendmsg net/socket.c:2173 [inline]
 __se_sys_sendmsg net/socket.c:2171 [inline]
 __x64_sys_sendmsg+0x32d/0x460 net/socket.c:2171
 do_syscall_64+0x15b/0x220 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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