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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
 __nr_to_section include/linux/mmzone.h:1844 [inline]
 __pfn_to_section include/linux/mmzone.h:1952 [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+0x191/0x2c0 mm/kmsan/shadow.c:143
 kmsan_get_shadow_origin_ptr+0x38/0xa0 mm/kmsan/shadow.c:97
 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_ptr+0x9b/0xd0 arch/x86/kernel/unwind_frame.c:28
 update_stack_state+0x177/0x1e0 arch/x86/kernel/unwind_frame.c:251
 unwind_next_frame+0x11d/0x360 arch/x86/kernel/unwind_frame.c:315
 arch_stack_walk+0x19e/0x250 arch/x86/kernel/stacktrace.c:25
 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:3470 [inline]
 slab_alloc mm/slub.c:3478 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3485 [inline]
 kmem_cache_alloc+0x4fa/0x9f0 mm/slub.c:3494
 mt_alloc_one lib/maple_tree.c:159 [inline]
 mas_alloc_nodes+0x569/0xec0 lib/maple_tree.c:1282
 mas_node_count_gfp lib/maple_tree.c:1362 [inline]
 mas_preallocate+0x220/0x600 lib/maple_tree.c:5547
 vma_iter_prealloc mm/internal.h:1032 [inline]
 mmap_region+0x28a2/0x4290 mm/mmap.c:2810
 do_mmap+0xe6a/0x1890 mm/mmap.c:1363
 vm_mmap_pgoff+0x223/0x4e0 mm/util.c:543
 ksys_mmap_pgoff+0x631/0x770 mm/mmap.c:1409
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:93 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline]
 __x64_sys_mmap+0x16d/0x200 arch/x86/kernel/sys_x86_64.c:86
 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+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: 1 PID: 5791 Comm: dhcpcd-run-hook Not tainted 6.5.0-rc7-syzkaller-00104-g4f9e7fabf864 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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