=====================================================
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
 valid_section include/linux/mmzone.h:1907 [inline]
 pfn_valid include/linux/mmzone.h:2003 [inline]
 kmsan_virt_addr_valid arch/x86/include/asm/kmsan.h:82 [inline]
 virt_to_page_or_null mm/kmsan/shadow.c:75 [inline]
 kmsan_get_metadata+0x1cc/0x2c0 mm/kmsan/shadow.c:143
 kmsan_get_shadow_origin_ptr+0x4d/0xa0 mm/kmsan/shadow.c:102
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:36 [inline]
 __msan_metadata_ptr_for_load_8+0x24/0x40 mm/kmsan/instrumentation.c:92
 unwind_get_return_address+0x76/0x140 arch/x86/kernel/unwind_frame.c:19
 arch_stack_walk+0x161/0x2c0 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0xa9/0xe0 kernel/stacktrace.c:122
 kmsan_save_stack_with_flags mm/kmsan/core.c:74 [inline]
 kmsan_internal_poison_memory+0x49/0xa0 mm/kmsan/core.c:58
 kmsan_slab_alloc+0xdd/0x150 mm/kmsan/hooks.c:68
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x577/0xa80 mm/slub.c:3523
 __alloc_skb+0x1e5/0x740 net/core/skbuff.c:634
 alloc_skb include/linux/skbuff.h:1286 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
 nsim_dev_trap_report_work+0x3f1/0x1220 drivers/net/netdevsim/dev.c:850
 process_one_work+0xbf6/0x17c0 kernel/workqueue.c:2600
 worker_thread+0x107e/0x1d60 kernel/workqueue.c:2751
 kthread+0x3e8/0x540 kernel/kthread.c:388
 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:145
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

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
 __alloc_skb+0x318/0x740 net/core/skbuff.c:644
 alloc_skb include/linux/skbuff.h:1286 [inline]
 garp_pdu_init net/802/garp.c:225 [inline]
 garp_pdu_append_attr+0x299/0x1170 net/802/garp.c:296
 garp_attr_event+0x146/0x280 net/802/garp.c:338
 garp_gid_event net/802/garp.c:402 [inline]
 garp_join_timer+0xc5/0x2e0 net/802/garp.c:419
 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: 7 Comm: kworker/0:0 Not tainted 6.5.0-syzkaller-08894-gb97d64c72259 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
Workqueue: events nsim_dev_trap_report_work
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