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BUG: KMSAN: uninit-value in gue6_err+0x475/0xc40 net/ipv6/fou6.c:101
CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.0.0-rc1+ #10
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:600
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 gue6_err+0x475/0xc40 net/ipv6/fou6.c:101
 __udp6_lib_err_encap_no_sk net/ipv6/udp.c:434 [inline]
 __udp6_lib_err_encap net/ipv6/udp.c:491 [inline]
 __udp6_lib_err+0x18d0/0x2590 net/ipv6/udp.c:522
 udpv6_err+0x118/0x130 net/ipv6/udp.c:607
 icmpv6_notify+0x462/0x9f0 net/ipv6/icmp.c:784
 icmpv6_rcv+0x18ac/0x3fa0 net/ipv6/icmp.c:872
 ip6_protocol_deliver_rcu+0xb5a/0x23a0 net/ipv6/ip6_input.c:394
 ip6_input_finish net/ipv6/ip6_input.c:434 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_input+0x2b6/0x350 net/ipv6/ip6_input.c:443
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x4e7/0x6d0 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ipv6_rcv+0x34b/0x3f0 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core net/core/dev.c:4973 [inline]
 __netif_receive_skb net/core/dev.c:5083 [inline]
 process_backlog+0x756/0x10e0 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x78b/0x1a60 net/core/dev.c:6412
 __do_softirq+0x53f/0x93a kernel/softirq.c:293
 run_ksoftirqd+0x26/0x50 kernel/softirq.c:658
 smpboot_thread_fn+0x4d0/0x9f0 kernel/smpboot.c:164
 kthread+0x4a1/0x4e0 kernel/kthread.c:247
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:355

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:205 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:159
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2754 [inline]
 __kmalloc_node_track_caller+0xe9e/0xff0 mm/slub.c:4377
 __kmalloc_reserve net/core/skbuff.c:140 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:208
 alloc_skb include/linux/skbuff.h:1012 [inline]
 alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5288
 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2091
 sock_alloc_send_skb+0xca/0xe0 net/core/sock.c:2108
 __ip6_append_data+0x42ed/0x5dc0 net/ipv6/ip6_output.c:1443
 ip6_append_data+0x3c2/0x650 net/ipv6/ip6_output.c:1619
 icmp6_send+0x2f5c/0x3c40 net/ipv6/icmp.c:574
 icmpv6_send+0xe5/0x110 net/ipv6/ip6_icmp.c:43
 ip6_link_failure+0x5c/0x2c0 net/ipv6/route.c:2231
 dst_link_failure include/net/dst.h:427 [inline]
 ndisc_error_report+0x106/0x1a0 net/ipv6/ndisc.c:695
 neigh_invalidate+0x359/0x8e0 net/core/neighbour.c:987
 neigh_timer_handler+0xdf2/0x1280 net/core/neighbour.c:1073
 call_timer_fn+0x285/0x600 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers+0xdb4/0x11d0 kernel/time/timer.c:1681
 run_timer_softirq+0x2e/0x50 kernel/time/timer.c:1694
 __do_softirq+0x53f/0x93a kernel/softirq.c:293
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