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BUG: KMSAN: uninit-value in ipv6_ext_hdr net/ipv6/exthdrs_core.c:17 [inline]
BUG: KMSAN: uninit-value in ipv6_skip_exthdr+0x156/0x910 net/ipv6/exthdrs_core.c:78
CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.18.0-rc4+ #23
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+0x185/0x1e0 lib/dump_stack.c:113
 kmsan_report+0x195/0x2c0 mm/kmsan/kmsan.c:990
 __msan_warning_32+0x7d/0xe0 mm/kmsan/kmsan_instr.c:640
 ipv6_ext_hdr net/ipv6/exthdrs_core.c:17 [inline]
 ipv6_skip_exthdr+0x156/0x910 net/ipv6/exthdrs_core.c:78
 ipv6_get_l4proto+0x1be/0x2f0 net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c:83
 nf_conntrack_in+0x54a/0x2070 net/netfilter/nf_conntrack_core.c:1388
 ipv6_conntrack_in+0xc3/0xf0 net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c:172
 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline]
 nf_hook_slow+0x15d/0x3e0 net/netfilter/core.c:511
 nf_hook include/linux/netfilter.h:242 [inline]
 NF_HOOK include/linux/netfilter.h:285 [inline]
 ipv6_rcv+0x1df5/0x2250 net/ipv6/ip6_input.c:208
 __netif_receive_skb_core+0x4a7a/0x4fc0 net/core/dev.c:4628
 __netif_receive_skb net/core/dev.c:4693 [inline]
 process_backlog+0x664/0xe60 net/core/dev.c:5373
 napi_poll net/core/dev.c:5771 [inline]
 net_rx_action+0x799/0x1ae0 net/core/dev.c:5837
 __do_softirq+0x55f/0x934 kernel/softirq.c:288
 run_ksoftirqd+0x24/0x40 kernel/softirq.c:652
 smpboot_thread_fn+0x4c1/0x9d0 kernel/smpboot.c:164
 kthread+0x473/0x4b0 kernel/kthread.c:247
 ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:415

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:271 [inline]
 kmsan_internal_chain_origin+0x13c/0x240 mm/kmsan/kmsan.c:581
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:425
 __msan_memcpy+0xe7/0x150 mm/kmsan/kmsan_instr.c:432
 skb_copy_from_linear_data_offset include/linux/skbuff.h:3385 [inline]
 skb_copy_bits+0x1f9/0xd80 net/core/skbuff.c:2038
 ipv6_get_l4proto+0x105/0x2f0 net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c:78
 nf_conntrack_in+0x54a/0x2070 net/netfilter/nf_conntrack_core.c:1388
 ipv6_conntrack_in+0xc3/0xf0 net/ipv6/netfilter/nf_conntrack_l3proto_ipv6.c:172
 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline]
 nf_hook_slow+0x15d/0x3e0 net/netfilter/core.c:511
 nf_hook include/linux/netfilter.h:242 [inline]
 NF_HOOK include/linux/netfilter.h:285 [inline]
 ipv6_rcv+0x1df5/0x2250 net/ipv6/ip6_input.c:208
 __netif_receive_skb_core+0x4a7a/0x4fc0 net/core/dev.c:4628
 __netif_receive_skb net/core/dev.c:4693 [inline]
 process_backlog+0x664/0xe60 net/core/dev.c:5373
 napi_poll net/core/dev.c:5771 [inline]
 net_rx_action+0x799/0x1ae0 net/core/dev.c:5837
 __do_softirq+0x55f/0x934 kernel/softirq.c:288

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_save_stack mm/kmsan/kmsan.c:271 [inline]
 kmsan_internal_chain_origin+0x13c/0x240 mm/kmsan/kmsan.c:581
 kmsan_memcpy_origins+0x11d/0x170 mm/kmsan/kmsan.c:425
 kmsan_memmove_origins+0x9/0x10 mm/kmsan/kmsan.c:480
 __msan_memmove+0xe7/0x150 mm/kmsan/kmsan_instr.c:381
 nf_ct_frag6_reasm net/ipv6/netfilter/nf_conntrack_reasm.c:432 [inline]
 nf_ct_frag6_gather+0x436a/0x5870 net/ipv6/netfilter/nf_conntrack_reasm.c:586
 ipv6_defrag+0x501/0x5c0 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:71
 nf_hook_entry_hookfn include/linux/netfilter.h:119 [inline]
 nf_hook_slow+0x15d/0x3e0 net/netfilter/core.c:511
 nf_hook include/linux/netfilter.h:242 [inline]
 NF_HOOK include/linux/netfilter.h:285 [inline]
 ipv6_rcv+0x1df5/0x2250 net/ipv6/ip6_input.c:208
 __netif_receive_skb_core+0x4a7a/0x4fc0 net/core/dev.c:4628
 __netif_receive_skb net/core/dev.c:4693 [inline]
 process_backlog+0x664/0xe60 net/core/dev.c:5373
 napi_poll net/core/dev.c:5771 [inline]
 net_rx_action+0x799/0x1ae0 net/core/dev.c:5837
 __do_softirq+0x55f/0x934 kernel/softirq.c:288

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0xa1/0x120 mm/kmsan/kmsan_hooks.c:91
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:100
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2720 [inline]
 __kmalloc_node_track_caller+0xb48/0x11d0 mm/slub.c:4353
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cb/0x9e0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:988 [inline]
 __ip6_append_data+0x3c45/0x5320 net/ipv6/ip6_output.c:1427
 ip6_append_data+0x40e/0x6b0 net/ipv6/ip6_output.c:1590
 rawv6_sendmsg+0x2909/0x5410 net/ipv6/raw.c:928
 inet_sendmsg+0x3fc/0x760 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:641 [inline]
 sock_sendmsg net/socket.c:651 [inline]
 ___sys_sendmsg+0xed9/0x1350 net/socket.c:2125
 __sys_sendmsg net/socket.c:2163 [inline]
 __do_sys_sendmsg net/socket.c:2172 [inline]
 __se_sys_sendmsg net/socket.c:2170 [inline]
 __x64_sys_sendmsg+0x3b0/0x520 net/socket.c:2170
 do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
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