syzbot

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BUG: KMSAN: uninit-value in eth_type_trans+0x621/0x800 net/ethernet/eth.c:169
 eth_type_trans+0x621/0x800 net/ethernet/eth.c:169
 ip_tunnel_rcv+0x29ca/0x3020 net/ipv4/ip_tunnel.c:411
 erspan_rcv net/ipv4/ip_gre.c:341 [inline]
 gre_rcv+0x15ef/0x19d0 net/ipv4/ip_gre.c:442
 gre_rcv+0x2a4/0x390 net/ipv4/gre_demux.c:163
 ip_protocol_deliver_rcu+0x264/0x1320 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x2b8/0x440 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip_local_deliver+0x241/0x4b0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:454 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:449 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip_rcv+0x4b0/0x7c0 net/ipv4/ip_input.c:569
 __netif_receive_skb_one_core net/core/dev.c:5480 [inline]
 __netif_receive_skb+0x1b8/0x5e0 net/core/dev.c:5594
 process_backlog+0x480/0x8b0 net/core/dev.c:5922
 __napi_poll+0xe4/0x950 net/core/dev.c:6483
 napi_poll net/core/dev.c:6550 [inline]
 net_rx_action+0x8d3/0x19d0 net/core/dev.c:6660
 __do_softirq+0x1c9/0x7c5 kernel/softirq.c:571
 do_softirq+0x141/0x1f0 kernel/softirq.c:472
 __local_bh_enable_ip+0x97/0xa0 kernel/softirq.c:396
 local_bh_enable+0x28/0x30 include/linux/bottom_half.h:33
 rcu_read_unlock_bh include/linux/rcupdate.h:843 [inline]
 ip_finish_output2+0x184a/0x1a60 net/ipv4/ip_output.c:229
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x4b/0x420 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip_output+0x215/0x500 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x110/0x2a0 net/ipv4/ip_output.c:1586
 udp_send_skb+0xff9/0x1b00 net/ipv4/udp.c:978
 udp_sendmsg+0x3145/0x3510 net/ipv4/udp.c:1265
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 sock_write_iter+0x4b0/0x660 net/socket.c:1138
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x834/0x1580 fs/read_write.c:584
 ksys_write+0x21f/0x4f0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was stored to memory at:
 pskb_expand_head+0x312/0x1a30 net/core/skbuff.c:2001
 __skb_cow include/linux/skbuff.h:3563 [inline]
 skb_cow_head include/linux/skbuff.h:3597 [inline]
 ip_tunnel_xmit+0x3a1f/0x4230 net/ipv4/ip_tunnel.c:806
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 erspan_xmit+0x13d1/0x1f00 net/ipv4/ip_gre.c:715
 __netdev_start_xmit include/linux/netdevice.h:4884 [inline]
 netdev_start_xmit include/linux/netdevice.h:4898 [inline]
 xmit_one net/core/dev.c:3581 [inline]
 dev_hard_start_xmit+0x253/0xa20 net/core/dev.c:3597
 sch_direct_xmit+0x3f7/0xdc0 net/sched/sch_generic.c:342
 __dev_xmit_skb net/core/dev.c:3808 [inline]
 __dev_queue_xmit+0x3601/0x5ac0 net/core/dev.c:4213
 dev_queue_xmit include/linux/netdevice.h:3054 [inline]
 neigh_resolve_output+0x99a/0xab0 net/core/neighbour.c:1583
 neigh_output include/net/neighbour.h:546 [inline]
 ip_finish_output2+0x1834/0x1a60 net/ipv4/ip_output.c:228
 __ip_finish_output+0x266/0x720
 ip_finish_output+0x4b/0x420 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip_output+0x215/0x500 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 ip_send_skb+0x110/0x2a0 net/ipv4/ip_output.c:1586
 udp_send_skb+0xff9/0x1b00 net/ipv4/udp.c:978
 udp_sendmsg+0x3145/0x3510 net/ipv4/udp.c:1265
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 sock_write_iter+0x4b0/0x660 net/socket.c:1138
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x834/0x1580 fs/read_write.c:584
 ksys_write+0x21f/0x4f0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12d/0xb60 mm/slab.h:774
 slab_alloc_node mm/slub.c:3452 [inline]
 kmem_cache_alloc_node+0x543/0xab0 mm/slub.c:3497
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:520
 __alloc_skb+0x3a7/0x850 net/core/skbuff.c:606
 alloc_skb include/linux/skbuff.h:1278 [inline]
 alloc_skb_with_frags+0xbd/0xbb0 net/core/skbuff.c:6318
 sock_alloc_send_pskb+0xaad/0xc30 net/core/sock.c:2734
 sock_alloc_send_skb include/net/sock.h:1860 [inline]
 __ip_append_data+0x448d/0x6430 net/ipv4/ip_output.c:1120
 ip_make_skb+0x1ee/0x640 net/ipv4/ip_output.c:1652
 udp_sendmsg+0x2ffe/0x3510 net/ipv4/udp.c:1260
 inet_sendmsg+0x105/0x190 net/ipv4/af_inet.c:825
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 sock_write_iter+0x4b0/0x660 net/socket.c:1138
 call_write_iter include/linux/fs.h:1851 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x834/0x1580 fs/read_write.c:584
 ksys_write+0x21f/0x4f0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 0 PID: 4976 Comm: syz-executor163 Not tainted 6.3.0-syzkaller-g81af97bdef5e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023
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