=====================================================
BUG: KMSAN: uninit-value in eth_skb_pkt_type include/linux/etherdevice.h:629 [inline]
BUG: KMSAN: uninit-value in eth_type_trans+0x7d5/0x9b0 net/ethernet/eth.c:165
 eth_skb_pkt_type include/linux/etherdevice.h:629 [inline]
 eth_type_trans+0x7d5/0x9b0 net/ethernet/eth.c:165
 ip_tunnel_rcv+0x215f/0x29c0 net/ipv4/ip_tunnel.c:439
 erspan_rcv net/ipv4/ip_gre.c:356 [inline]
 gre_rcv+0x1ca4/0x20f0 net/ipv4/ip_gre.c:460
 gre_rcv+0x285/0x380 net/ipv4/gre_demux.c:163
 ip_protocol_deliver_rcu+0xb3d/0x13d0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x409/0x720 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_local_deliver+0x228/0x4a0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:480 [inline]
 ip_rcv_finish+0x4d7/0x560 net/ipv4/ip_input.c:453
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_rcv+0xcb/0x370 net/ipv4/ip_input.c:573
 __netif_receive_skb_one_core net/core/dev.c:6181 [inline]
 __netif_receive_skb net/core/dev.c:6294 [inline]
 process_backlog+0x8d7/0x1500 net/core/dev.c:6645
 __napi_poll+0xdc/0x950 net/core/dev.c:7709
 napi_poll net/core/dev.c:7772 [inline]
 net_rx_action+0xa5b/0x1c70 net/core/dev.c:7929
 handle_softirqs+0x171/0x7e0 kernel/softirq.c:622
 __do_softirq+0x14/0x1b kernel/softirq.c:656
 do_softirq+0x58/0x90 kernel/softirq.c:523
 __local_bh_enable_ip+0xa1/0xb0 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
 __dev_queue_xmit+0x384a/0x5980 net/core/dev.c:4890
 dev_queue_xmit include/linux/netdevice.h:3385 [inline]
 neigh_resolve_output+0x9c3/0xaf0 net/core/neighbour.c:1620
 neigh_output include/net/neighbour.h:556 [inline]
 ip_finish_output2+0x1afd/0x1e00 net/ipv4/ip_output.c:237
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x288/0x860 net/ipv4/ip_output.c:325
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0x14f/0x3e0 net/ipv4/ip_output.c:438
 dst_output include/net/dst.h:470 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 ip_send_skb+0x32a/0x3d0 net/ipv4/ip_output.c:1508
 udp_send_skb+0x1373/0x1c80 net/ipv4/udp.c:1195
 udp_sendmsg+0x3049/0x33c0 net/ipv4/udp.c:1485
 udpv6_sendmsg+0x1693/0x3ff0 net/ipv6/udp.c:1545
 inet6_sendmsg+0x1ef/0x290 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x992/0xfd0 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2762 [inline]
 __se_sys_sendmmsg net/socket.c:2759 [inline]
 __x64_sys_sendmmsg+0xc6/0x150 net/socket.c:2759
 x64_sys_call+0x2f8c/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4545 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_node_noprof+0x3cd/0x12d0 mm/slub.c:4918
 kmalloc_reserve net/core/skbuff.c:613 [inline]
 __alloc_skb+0x855/0x1190 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6763
 sock_alloc_send_pskb+0xacb/0xc60 net/core/sock.c:2995
 sock_alloc_send_skb include/net/sock.h:1894 [inline]
 __ip_append_data+0x4d7d/0x7030 net/ipv4/ip_output.c:1127
 ip_make_skb+0x1de/0x5f0 net/ipv4/ip_output.c:1574
 udp_sendmsg+0x2834/0x33c0 net/ipv4/udp.c:1480
 udpv6_sendmsg+0x1693/0x3ff0 net/ipv6/udp.c:1545
 inet6_sendmsg+0x1ef/0x290 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x992/0xfd0 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2735
 __do_sys_sendmmsg net/socket.c:2762 [inline]
 __se_sys_sendmmsg net/socket.c:2759 [inline]
 __x64_sys_sendmmsg+0xc6/0x150 net/socket.c:2759
 x64_sys_call+0x2f8c/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 0 UID: 0 PID: 17941 Comm: syz.1.3919 Tainted: G        W    L      syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN, [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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