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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:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3545 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3561
 __dev_queue_xmit+0x33b8/0x5130 net/core/dev.c:4346
 dev_queue_xmit include/linux/netdevice.h:3134 [inline]
 garp_queue_xmit net/802/garp.c:273 [inline]
 garp_join_timer+0x18e/0x2e0 net/802/garp.c:424
 call_timer_fn+0x45/0x570 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+0x1b7/0x7c3 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:1076
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:645
 in_irqentry_text kernel/stacktrace.c:379 [inline]
 filter_irq_stacks+0x6b/0x1a0 kernel/stacktrace.c:397
 __stack_depot_save+0x22/0x490 lib/stackdepot.c:377
 kmsan_save_stack_with_flags mm/kmsan/core.c:79 [inline]
 kmsan_internal_poison_memory+0x62/0xa0 mm/kmsan/core.c:58
 kmsan_slab_free+0xd1/0x130 mm/kmsan/hooks.c:89
 slab_free_hook mm/slub.c:1770 [inline]
 slab_free_freelist_hook mm/slub.c:1826 [inline]
 slab_free mm/slub.c:3809 [inline]
 kmem_cache_free+0x66f/0x1250 mm/slub.c:3831
 __kfree_skb+0x1f8/0x250 net/core/skbuff.c:1073
 kfree_skb_reason+0x125/0x4f0 net/core/skbuff.c:1108
 netlink_broadcast_filtered+0x1053/0x2390 net/netlink/af_netlink.c:1552
 netlink_broadcast net/netlink/af_netlink.c:1576 [inline]
 netlink_sendmsg+0x11cc/0x13d0 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2584
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2638
 __sys_sendmsg net/socket.c:2667 [inline]
 __do_sys_sendmsg net/socket.c:2676 [inline]
 __se_sys_sendmsg net/socket.c:2674 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2674
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
 slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 __kmem_cache_alloc_node+0x5c9/0x970 mm/slub.c:3517
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc_node_track_caller+0x118/0x3c0 mm/slab_common.c:1027
 kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:582
 pskb_expand_head+0x226/0x1a00 net/core/skbuff.c:2098
 __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:4940 [inline]
 netdev_start_xmit include/linux/netdevice.h:4954 [inline]
 xmit_one net/core/dev.c:3545 [inline]
 dev_hard_start_xmit+0x247/0xa10 net/core/dev.c:3561
 __dev_queue_xmit+0x33b8/0x5130 net/core/dev.c:4346
 dev_queue_xmit include/linux/netdevice.h:3134 [inline]
 garp_queue_xmit net/802/garp.c:273 [inline]
 garp_join_timer+0x18e/0x2e0 net/802/garp.c:424
 call_timer_fn+0x45/0x570 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+0x1b7/0x7c3 kernel/softirq.c:553

CPU: 1 PID: 5459 Comm: udevd Not tainted 6.7.0-rc2-syzkaller-00195-g0f5cc96c367f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
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