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BUG: KMSAN: uninit-value in decode_session6 net/xfrm/xfrm_policy.c:3407 [inline]
BUG: KMSAN: uninit-value in __xfrm_decode_session+0x10f8/0x3430 net/xfrm/xfrm_policy.c:3482
CPU: 0 PID: 3364 Comm: syz-executor.2 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf8/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 decode_session6 net/xfrm/xfrm_policy.c:3407 [inline]
 __xfrm_decode_session+0x10f8/0x3430 net/xfrm/xfrm_policy.c:3482
 xfrm_decode_session_reverse include/net/xfrm.h:1144 [inline]
 icmpv6_route_lookup net/ipv6/icmp.c:369 [inline]
 icmp6_send+0x32e3/0x3720 net/ipv6/icmp.c:569
 icmpv6_send+0xe4/0x110 net/ipv6/ip6_icmp.c:43
 ip6_link_failure+0x68/0x580 net/ipv6/route.c:2641
 dst_link_failure include/net/dst.h:419 [inline]
 ip6_tnl_xmit+0xdda/0x4270 net/ipv6/ip6_tunnel.c:1222
 ip6ip6_tnl_xmit net/ipv6/ip6_tunnel.c:1376 [inline]
 ip6_tnl_start_xmit+0x236e/0x2560 net/ipv6/ip6_tunnel.c:1402
 __netdev_start_xmit include/linux/netdevice.h:4447 [inline]
 netdev_start_xmit include/linux/netdevice.h:4461 [inline]
 xmit_one net/core/dev.c:3420 [inline]
 dev_hard_start_xmit+0x51a/0xab0 net/core/dev.c:3436
 sch_direct_xmit+0x515/0x18c0 net/sched/sch_generic.c:314
 qdisc_restart net/sched/sch_generic.c:377 [inline]
 __qdisc_run+0x15de/0x3350 net/sched/sch_generic.c:385
 __dev_xmit_skb net/core/dev.c:3677 [inline]
 __dev_queue_xmit+0x2335/0x4280 net/core/dev.c:3982
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4046
 neigh_direct_output+0x42/0x50 net/core/neighbour.c:1530
 neigh_output include/net/neighbour.h:511 [inline]
 ip6_finish_output2+0x2129/0x2670 net/ipv6/ip6_output.c:116
 ip6_fragment+0x249a/0x3890 net/ipv6/ip6_output.c:860
 __ip6_finish_output+0x753/0x8f0 net/ipv6/ip6_output.c:140
 ip6_finish_output+0x2db/0x420 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x60a/0x770 net/ipv6/ip6_output.c:175
 dst_output include/net/dst.h:436 [inline]
 ip6_local_out+0x164/0x1d0 net/ipv6/output_core.c:179
 ip6_send_skb net/ipv6/ip6_output.c:1795 [inline]
 ip6_push_pending_frames+0x215/0x4f0 net/ipv6/ip6_output.c:1815
 rawv6_push_pending_frames net/ipv6/raw.c:613 [inline]
 rawv6_sendmsg+0x4b5f/0x5b00 net/ipv6/raw.c:956
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg net/socket.c:659 [inline]
 __sys_sendto+0xae0/0xc70 net/socket.c:1985
 __do_sys_sendto net/socket.c:1997 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1993
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1993
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45a919
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fb8b2001c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045a919
RDX: 000000000000ff77 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000004d97
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb8b20026d4
R13: 00000000004c9abf R14: 00000000004e1a38 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8b/0xe0 mm/kmsan/kmsan_hooks.c:82
 slab_alloc_node mm/slub.c:2774 [inline]
 __kmalloc_node_track_caller+0xe47/0x11f0 mm/slub.c:4382
 __kmalloc_reserve net/core/skbuff.c:141 [inline]
 __alloc_skb+0x309/0xa50 net/core/skbuff.c:209
 alloc_skb include/linux/skbuff.h:1049 [inline]
 __ip6_append_data+0x48bc/0x6350 net/ipv6/ip6_output.c:1518
 ip6_append_data+0x3cd/0x660 net/ipv6/ip6_output.c:1687
 rawv6_sendmsg+0x327d/0x5b00 net/ipv6/raw.c:949
 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg net/socket.c:659 [inline]
 __sys_sendto+0xae0/0xc70 net/socket.c:1985
 __do_sys_sendto net/socket.c:1997 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1993
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1993
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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