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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: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+0x34bb/0x52b0 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
 do_softirq+0x9a/0xf0 kernel/softirq.c:454
 __local_bh_enable_ip+0x99/0xa0 kernel/softirq.c:381
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
 _raw_spin_unlock_bh+0x2d/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 __fib6_clean_all net/ipv6/ip6_fib.c:2268 [inline]
 fib6_clean_all+0x207/0x300 net/ipv6/ip6_fib.c:2277
 rt6_sync_up+0x142/0x160 net/ipv6/route.c:4778
 addrconf_notify+0x16bc/0x1c40 net/ipv6/addrconf.c:3686
 notifier_call_chain kernel/notifier.c:93 [inline]
 raw_notifier_call_chain+0xe4/0x430 kernel/notifier.c:461
 __dev_notify_flags+0x4eb/0x9f0
 rtnl_newlink_create net/core/rtnetlink.c:3493 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3705 [inline]
 rtnl_newlink+0x3530/0x4110 net/core/rtnetlink.c:3718
 rtnetlink_rcv_msg+0x16a6/0x1840 net/core/rtnetlink.c:6444
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6462
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0xf47/0x1250 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2558
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2612
 __sys_sendmsg net/socket.c:2641 [inline]
 __do_sys_sendmsg net/socket.c:2650 [inline]
 __se_sys_sendmsg net/socket.c:2648 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2648
 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: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+0x249/0x4a0 net/core/skbuff.c:581
 __alloc_skb+0x318/0x740 net/core/skbuff.c:650
 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: 1 PID: 11546 Comm: syz-executor.0 Not tainted 6.6.0-rc4-syzkaller-00158-gf291209eca5e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
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