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BUG: KMSAN: uninit-value in __netif_receive_skb_core+0x36b1/0x5890 net/core/dev.c:5197
CPU: 0 PID: 14276 Comm: syz-executor.1 Not tainted 5.8.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1df/0x240 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 __netif_receive_skb_core+0x36b1/0x5890 net/core/dev.c:5197
 __netif_receive_skb_one_core net/core/dev.c:5279 [inline]
 __netif_receive_skb net/core/dev.c:5395 [inline]
 process_backlog+0x605/0x14e0 net/core/dev.c:6239
 napi_poll net/core/dev.c:6684 [inline]
 net_rx_action+0x746/0x1aa0 net/core/dev.c:6752
 __do_softirq+0x311/0x83d kernel/softirq.c:293
 asm_call_on_stack+0x12/0x20 arch/x86/entry/entry_64.S:711
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:23 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:338 [inline]
 __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
 __dev_queue_xmit+0x338e/0x3b20 net/core/dev.c:4158
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x763f/0x87a0 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0xc56/0xc90 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f9a549
Code: Bad RIP value.
RSP: 002b:00000000f55940cc EFLAGS: 00000296 ORIG_RAX: 0000000000000171
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000200001c0
RDX: 000000000001000d RSI: 0000000000000000 RDI: 0000000020000240
RBP: 0000000000000014 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 vlan_set_encap_proto include/linux/if_vlan.h:656 [inline]
 skb_vlan_untag+0x9a2/0xdb0 net/core/skbuff.c:5431
 __netif_receive_skb_core+0x72d/0x5890 net/core/dev.c:5119
 __netif_receive_skb_one_core net/core/dev.c:5279 [inline]
 __netif_receive_skb net/core/dev.c:5395 [inline]
 process_backlog+0x605/0x14e0 net/core/dev.c:6239
 napi_poll net/core/dev.c:6684 [inline]
 net_rx_action+0x746/0x1aa0 net/core/dev.c:6752
 __do_softirq+0x311/0x83d kernel/softirq.c:293

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2839 [inline]
 __kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4478
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1083 [inline]
 alloc_skb_with_frags+0x18c/0xa70 net/core/skbuff.c:5770
 sock_alloc_send_pskb+0xada/0xc60 net/core/sock.c:2356
 packet_alloc_skb net/packet/af_packet.c:2827 [inline]
 packet_snd net/packet/af_packet.c:2922 [inline]
 packet_sendmsg+0x5f04/0x87a0 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 __sys_sendto+0xc56/0xc90 net/socket.c:1995
 __do_sys_sendto net/socket.c:2007 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:2003
 __ia32_sys_sendto+0x6e/0x90 net/socket.c:2003
 do_syscall_32_irqs_on arch/x86/entry/common.c:430 [inline]
 __do_fast_syscall_32+0x2aa/0x400 arch/x86/entry/common.c:477
 do_fast_syscall_32+0x6b/0xd0 arch/x86/entry/common.c:505
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:554
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
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