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BUG: KMSAN: uninit-value in _decode_session6+0x635/0x1630 net/ipv6/xfrm6_policy.c:149
CPU: 0 PID: 9259 Comm: syz-executor2 Not tainted 4.19.0-rc8+ #70
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x306/0x460 lib/dump_stack.c:113
 kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917
 __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500
 _decode_session6+0x635/0x1630 net/ipv6/xfrm6_policy.c:149
 __xfrm_decode_session+0x156/0x200 net/xfrm/xfrm_policy.c:2299
 xfrm_decode_session_reverse include/net/xfrm.h:1239 [inline]
 icmpv6_route_lookup net/ipv6/icmp.c:372 [inline]
 icmp6_send+0x3037/0x3c50 net/ipv6/icmp.c:551
 icmpv6_send+0xe5/0x110 net/ipv6/ip6_icmp.c:43
 ip6_input_finish+0x224e/0x2360 net/ipv6/ip6_input.c:404
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_input+0x29d/0x340 net/ipv6/ip6_input.c:426
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x4d2/0x710 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ipv6_rcv+0x34b/0x3f0 net/ipv6/ip6_input.c:271
 __netif_receive_skb_one_core net/core/dev.c:4913 [inline]
 __netif_receive_skb net/core/dev.c:5023 [inline]
 process_backlog+0x82b/0x11d0 net/core/dev.c:5829
 napi_poll net/core/dev.c:6249 [inline]
 net_rx_action+0x975/0x1cf0 net/core/dev.c:6315
 __do_softirq+0x601/0xa6d kernel/softirq.c:292
 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1055
 </IRQ>
 do_softirq kernel/softirq.c:336 [inline]
 __local_bh_enable_ip+0x139/0x170 kernel/softirq.c:189
 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32
 rcu_read_unlock_bh include/linux/rcupdate.h:723 [inline]
 ip6_finish_output2+0x20a6/0x21f0 net/ipv6/ip6_output.c:121
 ip6_fragment+0x378e/0x50c0 net/ipv6/ip6_output.c:843
 ip6_finish_output+0xad0/0xc80 net/ipv6/ip6_output.c:152
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x5a0/0x6e0 net/ipv6/ip6_output.c:171
 dst_output include/net/dst.h:444 [inline]
 ip6_local_out+0x164/0x1d0 net/ipv6/output_core.c:176
 ip6_send_skb net/ipv6/ip6_output.c:1695 [inline]
 ip6_push_pending_frames+0x218/0x4d0 net/ipv6/ip6_output.c:1715
 rawv6_push_pending_frames net/ipv6/raw.c:616 [inline]
 rawv6_sendmsg+0x4293/0x54d0 net/ipv6/raw.c:944
 inet_sendmsg+0x4d8/0x7f0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457569
Code: fd b3 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 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f3c5640bc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3c5640c6d4
R13: 00000000004c3522 R14: 00000000004d5328 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline]
 kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:180
 kmsan_kmalloc_large+0x90/0x100 mm/kmsan/kmsan_hooks.c:141
 kmalloc_large_node_hook mm/slub.c:1359 [inline]
 kmalloc_large_node mm/slub.c:3806 [inline]
 __kmalloc_node_track_caller+0x10a7/0x1400 mm/slub.c:4346
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 pskb_expand_head+0x319/0x1d00 net/core/skbuff.c:1461
 __pskb_pull_tail+0x1db/0x21c0 net/core/skbuff.c:1895
 pskb_may_pull include/linux/skbuff.h:2127 [inline]
 _decode_session6+0x7b0/0x1630 net/ipv6/xfrm6_policy.c:150
 __xfrm_decode_session+0x156/0x200 net/xfrm/xfrm_policy.c:2299
 xfrm_decode_session_reverse include/net/xfrm.h:1239 [inline]
 icmpv6_route_lookup net/ipv6/icmp.c:372 [inline]
 icmp6_send+0x3037/0x3c50 net/ipv6/icmp.c:551
 icmpv6_send+0xe5/0x110 net/ipv6/ip6_icmp.c:43
 ip6_input_finish+0x224e/0x2360 net/ipv6/ip6_input.c:404
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_input+0x29d/0x340 net/ipv6/ip6_input.c:426
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x4d2/0x710 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ipv6_rcv+0x34b/0x3f0 net/ipv6/ip6_input.c:271
 __netif_receive_skb_one_core net/core/dev.c:4913 [inline]
 __netif_receive_skb net/core/dev.c:5023 [inline]
 process_backlog+0x82b/0x11d0 net/core/dev.c:5829
 napi_poll net/core/dev.c:6249 [inline]
 net_rx_action+0x975/0x1cf0 net/core/dev.c:6315
 __do_softirq+0x601/0xa6d kernel/softirq.c:292
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