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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
 memset_orig+0x15/0xac arch/x86/lib/memset_64.S:51
 __msan_poison_alloca+0x15b/0x1a0 mm/kmsan/instrumentation.c:288
 __rseq_handle_notify_resume+0x524/0x22b0 kernel/rseq.c:333
 rseq_handle_notify_resume include/linux/sched.h:2338 [inline]
 resume_user_mode_work include/linux/resume_user_mode.h:61 [inline]
 exit_to_user_mode_loop+0x1d3/0x320 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x163/0x220 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x2a/0x140 kernel/entry/common.c:297
 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: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
 __alloc_skb+0x318/0x740 net/core/skbuff.c:644
 alloc_skb include/linux/skbuff.h:1289 [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: 4429 Comm: udevd Not tainted 6.5.0-rc7-syzkaller-00168-g7d2f353b2682 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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