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BUG: KMSAN: uninit-value in eth_type_vlan include/linux/if_vlan.h:283 [inline]
BUG: KMSAN: uninit-value in __skb_flow_dissect+0x26b0/0x6580 net/core/flow_dissector.c:758
CPU: 0 PID: 6578 Comm: syz-executor4 Not tainted 4.16.0+ #83
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+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:676
 eth_type_vlan include/linux/if_vlan.h:283 [inline]
 __skb_flow_dissect+0x26b0/0x6580 net/core/flow_dissector.c:758
 __skb_get_hash_symmetric+0x10b/0x230 net/core/flow_dissector.c:1217
 fanout_demux_hash net/packet/af_packet.c:1339 [inline]
 packet_rcv_fanout+0x38f/0x8d0 net/packet/af_packet.c:1454
 deliver_skb net/core/dev.c:1897 [inline]
 __netif_receive_skb_core+0xa8c/0x4a80 net/core/dev.c:4473
 __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
 </IRQ>
 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]
 __dev_queue_xmit+0x2a31/0x2b60 net/core/dev.c:3584
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3590
 packet_snd net/packet/af_packet.c:2944 [inline]
 packet_sendmsg+0x7c57/0x8a10 net/packet/af_packet.c:2969
 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: 0033:0x455319
RSP: 002b:00007f0e72036c68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f0e720376d4 RCX: 0000000000455319
RDX: 0000000000000004 RSI: 0000000020000080 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000020005fe4 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000004f8 R14: 00000000006fa7e0 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:521
 skb_vlan_untag+0x950/0xee0 include/linux/if_vlan.h:597
 __netif_receive_skb_core+0x70a/0x4a80 net/core/dev.c:4460
 __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
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 alloc_skb_with_frags+0x1d4/0xb20 net/core/skbuff.c:5234
 sock_alloc_send_pskb+0xb56/0x1190 net/core/sock.c:2085
 packet_alloc_skb net/packet/af_packet.c:2803 [inline]
 packet_snd net/packet/af_packet.c:2894 [inline]
 packet_sendmsg+0x6444/0x8a10 net/packet/af_packet.c:2969
 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
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