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BUG: KMSAN: uninit-value in _decode_session6+0x645/0x1650 net/ipv6/xfrm6_policy.c:149
CPU: 0 PID: 22575 Comm: syz-executor4 Not tainted 4.19.0-rc4+ #61
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+0x2f6/0x430 lib/dump_stack.c:113
 kmsan_report+0x183/0x2b0 mm/kmsan/kmsan.c:917
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:500
 _decode_session6+0x645/0x1650 net/ipv6/xfrm6_policy.c:149
 __xfrm_decode_session net/xfrm/xfrm_policy.c:2299 [inline]
 __xfrm_policy_check+0x407/0x3bc0 net/xfrm/xfrm_policy.c:2348
 __xfrm_policy_check2 include/net/xfrm.h:1196 [inline]
 xfrm_policy_check include/net/xfrm.h:1201 [inline]
 xfrm6_policy_check include/net/xfrm.h:1211 [inline]
 rawv6_rcv+0x307/0x1440 net/ipv6/raw.c:424
 ipv6_raw_deliver net/ipv6/raw.c:224 [inline]
 raw6_local_deliver+0x2042/0x23f0 net/ipv6/raw.c:240
 ip6_input_finish+0x558/0x2360 net/ipv6/ip6_input.c:345
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip6_input+0x290/0x320 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
IPVS: ftp: loaded support on port[0] = 21
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ipv6_rcv+0x32c/0x3c0 net/ipv6/ip6_input.c:271
 __netif_receive_skb_one_core net/core/dev.c:4891 [inline]
 __netif_receive_skb net/core/dev.c:5001 [inline]
 process_backlog+0xd89/0x11a0 net/core/dev.c:5807
 napi_poll net/core/dev.c:6227 [inline]
 net_rx_action+0x935/0x1c00 net/core/dev.c:6293
 __do_softirq+0x614/0xa72 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+0x119/0x150 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+0x1f41/0x2130 net/ipv6/ip6_output.c:121
 ip6_finish_output+0xbad/0xc70 net/ipv6/ip6_output.c:154
 NF_HOOK_COND include/linux/netfilter.h:276 [inline]
 ip6_output+0x572/0x6a0 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:1697 [inline]
 ip6_push_pending_frames+0x218/0x4d0 net/ipv6/ip6_output.c:1717
 rawv6_push_pending_frames net/ipv6/raw.c:616 [inline]
 rawv6_sendmsg+0x45f7/0x5680 net/ipv6/raw.c:933
 inet_sendmsg+0x4c5/0x7d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe70/0x1290 net/socket.c:2114
 __sys_sendmsg net/socket.c:2152 [inline]
 __do_sys_sendmsg net/socket.c:2161 [inline]
 __se_sys_sendmsg+0x2a3/0x3d0 net/socket.c:2159
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2159
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457579
Code: 1d b4 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 eb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f223ea03c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000000 RSI: 0000000020000a40 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f223ea046d4
R13: 00000000004c3536 R14: 00000000004d5328 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:180
 kmsan_kmalloc+0x98/0x100 mm/kmsan/kmsan_hooks.c:93
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:102
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2727 [inline]
 __kmalloc_node_track_caller+0xba6/0x13f0 mm/slub.c:4360
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 pskb_expand_head+0x326/0x1e10 net/core/skbuff.c:1461
 __pskb_pull_tail+0x1e3/0x21b0 net/core/skbuff.c:1895
 pskb_may_pull include/linux/skbuff.h:2127 [inline]
 _decode_session6+0x7c0/0x1650 net/ipv6/xfrm6_policy.c:150
 __xfrm_decode_session net/xfrm/xfrm_policy.c:2299 [inline]
 __xfrm_policy_check+0x407/0x3bc0 net/xfrm/xfrm_policy.c:2348
 __xfrm_policy_check2 include/net/xfrm.h:1196 [inline]
 xfrm_policy_check include/net/xfrm.h:1201 [inline]
 xfrm6_policy_check include/net/xfrm.h:1211 [inline]
 rawv6_rcv+0x307/0x1440 net/ipv6/raw.c:424
 ipv6_raw_deliver net/ipv6/raw.c:224 [inline]
 raw6_local_deliver+0x2042/0x23f0 net/ipv6/raw.c:240
 ip6_input_finish+0x558/0x2360 net/ipv6/ip6_input.c:345
 NF_HOOK include/linux/netfilter.h:287 [inline]
 ip6_input+0x290/0x320 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:287 [inline]
 ipv6_rcv+0x32c/0x3c0 net/ipv6/ip6_input.c:271
 __netif_receive_skb_one_core net/core/dev.c:4891 [inline]
 __netif_receive_skb net/core/dev.c:5001 [inline]
 process_backlog+0xd89/0x11a0 net/core/dev.c:5807
 napi_poll net/core/dev.c:6227 [inline]
 net_rx_action+0x935/0x1c00 net/core/dev.c:6293
 __do_softirq+0x614/0xa72 kernel/softirq.c:292
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