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BUG: KMSAN: uninit-value in ip_rcv_core+0xccd/0x1490 net/ipv4/ip_input.c:476
CPU: 0 PID: 8700 Comm: syz-executor250 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+0x21c/0x280 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
 ip_rcv_core+0xccd/0x1490 net/ipv4/ip_input.c:476
 ip_rcv+0xc7/0x810 net/ipv4/ip_input.c:535
 __netif_receive_skb_one_core net/core/dev.c:5281 [inline]
 __netif_receive_skb+0x265/0x670 net/core/dev.c:5395
 process_backlog+0x50d/0xba0 net/core/dev.c:6239
 napi_poll+0x43b/0xfd0 net/core/dev.c:6684
 net_rx_action+0x35c/0xd40 net/core/dev.c:6752
 __do_softirq+0x2ea/0x7f5 kernel/softirq.c:293
 asm_call_on_stack+0xf/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+0x41a8/0x4470 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+0x8542/0x9a80 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmsg+0x6d1/0x840 net/socket.c:2439
 __do_sys_sendmsg net/socket.c:2448 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2446
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2446
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4442b9
Code: Bad RIP value.
RSP: 002b:00007ffef9914568 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004442b9
RDX: 0000000000000000 RSI: 0000000020001780 RDI: 0000000000000003
RBP: 00007ffef9914580 R08: 00000000bb1414ac R09: 00000000bb1414ac
R10: 0000000000000004 R11: 0000000000000246 R12: 00007ffef99145b0
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
 iptunnel_xmit+0xbb8/0xf00 net/ipv4/ip_tunnel_core.c:75
 udp_tunnel_xmit_skb+0x52a/0x650 net/ipv4/udp_tunnel.c:190
 geneve_xmit_skb drivers/net/geneve.c:929 [inline]
 geneve_xmit+0x180e/0x3200 drivers/net/geneve.c:1005
 __netdev_start_xmit include/linux/netdevice.h:4611 [inline]
 netdev_start_xmit include/linux/netdevice.h:4625 [inline]
 xmit_one+0x3cf/0x750 net/core/dev.c:3556
 dev_hard_start_xmit net/core/dev.c:3572 [inline]
 __dev_queue_xmit+0x3aad/0x4470 net/core/dev.c:4131
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4164
 packet_snd net/packet/af_packet.c:2979 [inline]
 packet_sendmsg+0x8542/0x9a80 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmsg+0x6d1/0x840 net/socket.c:2439
 __do_sys_sendmsg net/socket.c:2448 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2446
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2446
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

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+0xeab/0x12e0 mm/slub.c:4478
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x35f/0xb30 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1083 [inline]
 alloc_skb_with_frags+0x1f2/0xc10 net/core/skbuff.c:5770
 sock_alloc_send_pskb+0xc83/0xe50 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+0x6abb/0x9a80 net/packet/af_packet.c:3004
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 ____sys_sendmsg+0xc82/0x1240 net/socket.c:2352
 ___sys_sendmsg net/socket.c:2406 [inline]
 __sys_sendmsg+0x6d1/0x840 net/socket.c:2439
 __do_sys_sendmsg net/socket.c:2448 [inline]
 __se_sys_sendmsg+0x97/0xb0 net/socket.c:2446
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2446
 do_syscall_64+0xad/0x160 arch/x86/entry/common.c:386
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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