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BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x857/0x3e80 net/ipv4/ip_tunnel.c:679
 ip_tunnel_xmit+0x857/0x3e80 net/ipv4/ip_tunnel.c:679
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0xd1c/0xe20 net/ipv4/ip_gre.c:662
 __netdev_start_xmit include/linux/netdevice.h:4910 [inline]
 netdev_start_xmit include/linux/netdevice.h:4924 [inline]
 xmit_one net/core/dev.c:3537 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3553
 __dev_queue_xmit+0x34eb/0x50f0 net/core/dev.c:4203
 dev_queue_xmit include/linux/netdevice.h:3088 [inline]
 garp_queue_xmit net/802/garp.c:272 [inline]
 garp_join_timer+0x18e/0x2e0 net/802/garp.c:423
 call_timer_fn+0x45/0x4e0 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x850/0xf60 kernel/time/timer.c:2022
 run_timer_softirq+0x26/0x40 kernel/time/timer.c:2035
 __do_softirq+0x1b7/0x78f kernel/softirq.c:553
 invoke_softirq kernel/softirq.c:427 [inline]
 __irq_exit_rcu kernel/softirq.c:632 [inline]
 irq_exit_rcu+0x69/0x120 kernel/softirq.c:644
 sysvec_apic_timer_interrupt+0x7a/0x90 arch/x86/kernel/apic/apic.c:1109
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:645
 console_flush_all+0xd88/0x13c0 kernel/printk/printk.c:2939
 console_unlock+0x18c/0x410 kernel/printk/printk.c:3007
 vprintk_emit+0x1fa/0x8a0 kernel/printk/printk.c:2307
 vprintk_default+0x3e/0x50 kernel/printk/printk.c:2318
 vprintk+0xfe/0x120 kernel/printk/printk_safe.c:50
 _printk+0x157/0x190 kernel/printk/printk.c:2328
 __netdev_printk+0x50f/0x960 net/core/dev.c:11239
 netdev_info+0x18a/0x1a0 net/core/dev.c:11286
 __dev_set_allmulti+0x469/0x580 net/core/dev.c:8390
 __dev_change_flags+0x869/0x930 net/core/dev.c:8552
 rtnl_configure_link net/core/rtnetlink.c:3283 [inline]
 rtnl_newlink_create net/core/rtnetlink.c:3480 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3689 [inline]
 rtnl_newlink+0x3051/0x4070 net/core/rtnetlink.c:3702
 rtnetlink_rcv_msg+0x16a6/0x1840 net/core/rtnetlink.c:6428
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2549
 rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6446
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0xf28/0x1230 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x122f/0x13d0 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2494
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2548
 __sys_sendmsg+0x225/0x3c0 net/socket.c:2577
 __compat_sys_sendmsg net/compat.c:346 [inline]
 __do_compat_sys_sendmsg net/compat.c:353 [inline]
 __se_compat_sys_sendmsg net/compat.c:350 [inline]
 __ia32_compat_sys_sendmsg+0x9d/0xe0 net/compat.c:350
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3470 [inline]
 __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3509
 __do_kmalloc_node mm/slab_common.c:984 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:1005
 kmalloc_reserve+0x248/0x470 net/core/skbuff.c:575
 pskb_expand_head+0x226/0x1a10 net/core/skbuff.c:2042
 __skb_cow include/linux/skbuff.h:3571 [inline]
 skb_cow_head include/linux/skbuff.h:3605 [inline]
 ipgre_xmit+0x74a/0xe20 net/ipv4/ip_gre.c:638
 __netdev_start_xmit include/linux/netdevice.h:4910 [inline]
 netdev_start_xmit include/linux/netdevice.h:4924 [inline]
 xmit_one net/core/dev.c:3537 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3553
 __dev_queue_xmit+0x34eb/0x50f0 net/core/dev.c:4203
 dev_queue_xmit include/linux/netdevice.h:3088 [inline]
 garp_queue_xmit net/802/garp.c:272 [inline]
 garp_join_timer+0x18e/0x2e0 net/802/garp.c:423
 call_timer_fn+0x45/0x4e0 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x850/0xf60 kernel/time/timer.c:2022
 run_timer_softirq+0x26/0x40 kernel/time/timer.c:2035
 __do_softirq+0x1b7/0x78f kernel/softirq.c:553

CPU: 0 PID: 6852 Comm: syz-executor.3 Not tainted 6.5.0-rc6-syzkaller-00027-g91aa6c412d7f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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