=====================================================
BUG: KMSAN: uninit-value in decode_session6 net/xfrm/xfrm_policy.c:3386 [inline]
BUG: KMSAN: uninit-value in __xfrm_decode_session+0x118e/0x2e50 net/xfrm/xfrm_policy.c:3456
 decode_session6 net/xfrm/xfrm_policy.c:3386 [inline]
 __xfrm_decode_session+0x118e/0x2e50 net/xfrm/xfrm_policy.c:3456
 vti6_tnl_xmit+0x7ef/0x3820
 __netdev_start_xmit include/linux/netdevice.h:4987 [inline]
 netdev_start_xmit include/linux/netdevice.h:5001 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3590
 dev_hard_start_xmit+0x18f/0x440 net/core/dev.c:3606
 sch_direct_xmit+0x5f5/0x1410 net/sched/sch_generic.c:342
 qdisc_restart net/sched/sch_generic.c:407 [inline]
 __qdisc_run+0x358/0x550 net/sched/sch_generic.c:415
 __dev_xmit_skb+0x998/0x28d0 net/core/dev.c:3875
 __dev_queue_xmit+0x1590/0x32a0 net/core/dev.c:4194
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4259
 neigh_connected_output+0x73c/0x7b0 net/core/neighbour.c:1552
 neigh_output include/net/neighbour.h:527 [inline]
 ip6_finish_output2+0x24d0/0x2c50 net/ipv6/ip6_output.c:126
 __ip6_finish_output+0xf46/0x10a0 net/ipv6/ip6_output.c:191
 ip6_finish_output+0x15c/0x4d0 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x4ac/0x7f0 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:450 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ndisc_send_skb+0xe3e/0x1740 net/ipv6/ndisc.c:508
 ndisc_send_rs+0xd15/0xd90 net/ipv6/ndisc.c:702
 addrconf_rs_timer+0x72d/0x990 net/ipv6/addrconf.c:3898
 call_timer_fn+0x81/0x550 kernel/time/timer.c:1421
 expire_timers+0x304/0x6e0 kernel/time/timer.c:1466
 __run_timers+0x694/0xa10 kernel/time/timer.c:1734
 run_timer_softirq+0x71/0xe0 kernel/time/timer.c:1747
 __do_softirq+0x1fe/0x7eb kernel/softirq.c:558
 invoke_softirq+0xa4/0x130 kernel/softirq.c:432
 __irq_exit_rcu kernel/softirq.c:636 [inline]
 irq_exit_rcu+0x76/0x130 kernel/softirq.c:648
 sysvec_apic_timer_interrupt+0xa2/0xc0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 smap_save arch/x86/include/asm/smap.h:62 [inline]
 __msan_poison_alloca+0x84/0x180 mm/kmsan/instrumentation.c:181
 ia32_setup_rt_frame+0x860/0x2550
 setup_rt_frame arch/x86/kernel/signal.c:775 [inline]
 handle_signal arch/x86/kernel/signal.c:825 [inline]
 arch_do_signal_or_restart+0xa27/0xe00 arch/x86/kernel/signal.c:870
 handle_signal_work kernel/entry/common.c:149 [inline]
 exit_to_user_mode_loop+0x1f6/0x490 kernel/entry/common.c:173
 exit_to_user_mode_prepare+0xda/0xf0 kernel/entry/common.c:208
 irqentry_exit_to_user_mode+0x15/0x30 kernel/entry/common.c:316
 irqentry_exit+0x12/0x40 kernel/entry/common.c:407
 exc_page_fault+0x76/0x150 arch/x86/mm/fault.c:1565
 asm_exc_page_fault+0x1e/0x30

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 slab_alloc_node mm/slub.c:3251 [inline]
 __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 __alloc_skb+0x545/0xf90 net/core/skbuff.c:426
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_uevent_skb+0x14b/0x420 lib/kobject_uevent.c:290
 uevent_net_broadcast_untagged lib/kobject_uevent.c:326 [inline]
 kobject_uevent_net_broadcast+0x7ec/0xe90 lib/kobject_uevent.c:409
 kobject_uevent_env+0xfb9/0x14a0 lib/kobject_uevent.c:593
 kobject_synth_uevent+0xcc5/0x1c00 lib/kobject_uevent.c:208
 uevent_store+0xa4/0x160 drivers/base/core.c:2410
 dev_attr_store+0x105/0x160 drivers/base/core.c:2111
 sysfs_kf_write+0x246/0x2c0 fs/sysfs/file.c:136
 kernfs_fop_write_iter+0x66a/0x9f0 fs/kernfs/file.c:296
 call_write_iter include/linux/fs.h:2162 [inline]
 new_sync_write fs/read_write.c:503 [inline]
 vfs_write+0x1318/0x2030 fs/read_write.c:590
 ksys_write+0x28c/0x520 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0xdb/0x120 fs/read_write.c:652
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x54/0xd0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x44/0xae

CPU: 0 PID: 21298 Comm: syz-executor.0 Not tainted 5.16.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
=====================================================