=====================================================
BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x8fa/0x4230 net/ipv4/ip_tunnel.c:661
 ip_tunnel_xmit+0x8fa/0x4230 net/ipv4/ip_tunnel.c:661
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0xd62/0xe70 net/ipv4/ip_gre.c:661
 __netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 netdev_start_xmit include/linux/netdevice.h:4833 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 __dev_queue_xmit+0x1dec/0x31f0 net/core/dev.c:4256
 dev_queue_xmit include/linux/netdevice.h:3008 [inline]
 garp_queue_xmit net/802/garp.c:272 [inline]
 garp_join_timer+0x18a/0x2e0 net/802/garp.c:423
 call_timer_fn+0x43/0x480 kernel/time/timer.c:1474
 expire_timers+0x272/0x610 kernel/time/timer.c:1519
 __run_timers+0x5bd/0x8c0 kernel/time/timer.c:1790
 run_timer_softirq+0x64/0xe0 kernel/time/timer.c:1803
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571
 do_softirq+0x13d/0x1e0 kernel/softirq.c:472
 __local_bh_enable_ip+0x93/0xa0 kernel/softirq.c:396
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
 _raw_spin_unlock_bh+0x29/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:394 [inline]
 __ip6_ins_rt net/ipv6/route.c:1303 [inline]
 ip6_route_add+0x15f/0x300 net/ipv6/route.c:3847
 addrconf_prefix_route net/ipv6/addrconf.c:2425 [inline]
 addrconf_add_linklocal+0x8bd/0xb40 net/ipv6/addrconf.c:3217
 addrconf_addr_gen+0xb39/0xd20 net/ipv6/addrconf.c:3346
 addrconf_dev_config+0x455/0x580 net/ipv6/addrconf.c:3391
 addrconf_notify+0xe62/0x1d30 net/ipv6/addrconf.c:3631
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xbc/0x240 kernel/notifier.c:455
 __dev_notify_flags+0x4d5/0xa20
 rtnl_newlink_create net/core/rtnetlink.c:3371 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3580 [inline]
 rtnl_newlink+0x35be/0x40e0 net/core/rtnetlink.c:3593
 rtnetlink_rcv_msg+0x16c9/0x1860 net/core/rtnetlink.c:6090
 netlink_rcv_skb+0x3a5/0x6c0 net/netlink/af_netlink.c:2501
 rtnetlink_rcv+0x30/0x40 net/core/rtnetlink.c:6108
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg+0x258/0x440 net/socket.c:2565
 __compat_sys_sendmsg net/compat.c:343 [inline]
 __do_compat_sys_sendmsg net/compat.c:350 [inline]
 __se_compat_sys_sendmsg net/compat.c:347 [inline]
 __ia32_compat_sys_sendmsg+0x99/0xe0 net/compat.c:347
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:358 [inline]
 __alloc_skb+0x346/0xcf0 net/core/skbuff.c:430
 alloc_skb include/linux/skbuff.h:1257 [inline]
 garp_pdu_init net/802/garp.c:225 [inline]
 garp_pdu_append_attr+0x299/0x11c0 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+0xc1/0x2e0 net/802/garp.c:419
 call_timer_fn+0x43/0x480 kernel/time/timer.c:1474
 expire_timers+0x272/0x610 kernel/time/timer.c:1519
 __run_timers+0x5bd/0x8c0 kernel/time/timer.c:1790
 run_timer_softirq+0x64/0xe0 kernel/time/timer.c:1803
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571

CPU: 1 PID: 10698 Comm: syz-executor.0 Not tainted 6.0.0-rc4-syzkaller-48205-g4367d178d9eb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
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