=====================================================
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:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3544 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3560
 __dev_queue_xmit+0x34d0/0x52a0 net/core/dev.c:4340
 dev_queue_xmit include/linux/netdevice.h:3082 [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:1074
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:645
 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline]
 arch_local_irq_enable arch/x86/include/asm/irqflags.h:77 [inline]
 raw_spin_rq_unlock_irq kernel/sched/sched.h:1384 [inline]
 finish_lock_switch kernel/sched/core.c:5134 [inline]
 finish_task_switch+0x197/0x8a0 kernel/sched/core.c:5252
 context_switch kernel/sched/core.c:5385 [inline]
 __schedule+0x2687/0x7040 kernel/sched/core.c:6695
 schedule+0x148/0x220 kernel/sched/core.c:6771
 exit_to_user_mode_loop+0x68/0x320 kernel/entry/common.c:159
 exit_to_user_mode_prepare+0x163/0x220 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline]
 syscall_exit_to_user_mode+0x2a/0x140 kernel/entry/common.c:296
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3478 [inline]
 __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1022 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:1043
 kmalloc_reserve+0x248/0x470 net/core/skbuff.c:575
 pskb_expand_head+0x226/0x1a00 net/core/skbuff.c:2087
 __skb_cow include/linux/skbuff.h:3586 [inline]
 skb_cow_head include/linux/skbuff.h:3620 [inline]
 ipgre_xmit+0x74a/0xe20 net/ipv4/ip_gre.c:638
 __netdev_start_xmit include/linux/netdevice.h:4889 [inline]
 netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 xmit_one net/core/dev.c:3544 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3560
 __dev_queue_xmit+0x34d0/0x52a0 net/core/dev.c:4340
 dev_queue_xmit include/linux/netdevice.h:3082 [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: 1 PID: 5039 Comm: syz-executor.4 Not tainted 6.5.0-syzkaller-12145-g4a0fc73da97e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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