=====================================================
BUG: KMSAN: uninit-value in decode_session6 net/xfrm/xfrm_policy.c:3477 [inline]
BUG: KMSAN: uninit-value in __xfrm_decode_session+0x880/0x2890 net/xfrm/xfrm_policy.c:3566
 decode_session6 net/xfrm/xfrm_policy.c:3477 [inline]
 __xfrm_decode_session+0x880/0x2890 net/xfrm/xfrm_policy.c:3566
 xfrm_decode_session_reverse include/net/xfrm.h:1223 [inline]
 icmpv6_route_lookup+0x68b/0xa70 net/ipv6/icmp.c:388
 icmp6_send+0x2164/0x29b0 net/ipv6/icmp.c:595
 __icmpv6_send include/linux/icmpv6.h:28 [inline]
 icmpv6_send include/linux/icmpv6.h:49 [inline]
 ip6_link_failure+0x40/0x320 net/ipv6/route.c:2785
 dst_link_failure include/net/dst.h:437 [inline]
 ip6_tnl_xmit+0x22dc/0x3760 net/ipv6/ip6_tunnel.c:1268
 ipxip6_tnl_xmit net/ipv6/ip6_tunnel.c:1384 [inline]
 ip6_tnl_start_xmit+0x1851/0x1a70 net/ipv6/ip6_tunnel.c:1432
 __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
 sch_direct_xmit+0x3c5/0xd40 net/sched/sch_generic.c:342
 qdisc_restart net/sched/sch_generic.c:407 [inline]
 __qdisc_run+0x14ab/0x35a0 net/sched/sch_generic.c:415
 __dev_xmit_skb net/core/dev.c:3827 [inline]
 __dev_queue_xmit+0x1b43/0x50f0 net/core/dev.c:4169
 dev_queue_xmit include/linux/netdevice.h:3088 [inline]
 neigh_connected_output+0x569/0x660 net/core/neighbour.c:1581
 neigh_output include/net/neighbour.h:544 [inline]
 ip6_finish_output2+0x2179/0x28e0 net/ipv6/ip6_output.c:135
 __ip6_finish_output net/ipv6/ip6_output.c:196 [inline]
 ip6_finish_output+0xa10/0x1240 net/ipv6/ip6_output.c:207
 NF_HOOK_COND include/linux/netfilter.h:292 [inline]
 ip6_output+0x323/0x610 net/ipv6/ip6_output.c:228
 dst_output include/net/dst.h:458 [inline]
 ip6_local_out+0xe9/0x140 net/ipv6/output_core.c:155
 ip6_send_skb+0xb8/0x3a0 net/ipv6/ip6_output.c:2008
 udp_v6_send_skb+0x1449/0x2220 net/ipv6/udp.c:1302
 udp_v6_push_pending_frames+0x1f0/0x290 net/ipv6/udp.c:1329
 udpv6_sendmsg+0x1652/0x4000 net/ipv6/udp.c:1624
 inet6_sendmsg+0x105/0x190 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2494
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2548
 __sys_sendmmsg+0x3c4/0x950 net/socket.c:2634
 __do_sys_sendmmsg net/socket.c:2663 [inline]
 __se_sys_sendmmsg net/socket.c:2660 [inline]
 __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2660
 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:
 __alloc_pages+0x9a4/0xe00 mm/page_alloc.c:4500
 alloc_pages+0xd01/0x1040
 alloc_slab_page mm/slub.c:1862 [inline]
 allocate_slab mm/slub.c:2009 [inline]
 new_slab+0x41e/0x1580 mm/slub.c:2062
 ___slab_alloc+0x13c3/0x33b0 mm/slub.c:3215
 __slab_alloc mm/slub.c:3314 [inline]
 __slab_alloc_node mm/slub.c:3367 [inline]
 slab_alloc_node mm/slub.c:3460 [inline]
 kmem_cache_alloc_node+0x61d/0xa80 mm/slub.c:3515
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:559
 __alloc_skb+0x318/0x740 net/core/skbuff.c:644
 alloc_skb include/linux/skbuff.h:1289 [inline]
 alloc_skb_with_frags+0xbd/0xbb0 net/core/skbuff.c:6233
 sock_alloc_send_pskb+0xa80/0xbf0 net/core/sock.c:2793
 sock_alloc_send_skb include/net/sock.h:1871 [inline]
 __ip_append_data+0x49f0/0x69a0 net/ipv4/ip_output.c:1120
 ip_make_skb+0x1ce/0x610 net/ipv4/ip_output.c:1552
 udp_sendmsg+0x2d32/0x31b0 net/ipv4/udp.c:1260
 udpv6_sendmsg+0x1379/0x4000 net/ipv6/udp.c:1407
 inet6_sendmsg+0x105/0x190 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2494
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2548
 __sys_sendmmsg+0x3c4/0x950 net/socket.c:2634
 __do_sys_sendmmsg net/socket.c:2663 [inline]
 __se_sys_sendmmsg net/socket.c:2660 [inline]
 __x64_sys_sendmmsg+0xbc/0x120 net/socket.c:2660
 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

CPU: 1 PID: 27132 Comm: syz-executor.4 Not tainted 6.5.0-rc5-syzkaller-00296-gf8de32cc060b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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