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BUG: KMSAN: uninit-value in _decode_session6+0x645/0x1650 net/ipv6/xfrm6_policy.c:149
CPU: 1 PID: 4683 Comm: syz-executor1 Not tainted 4.19.0-rc4+ #56
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:956
 __msan_warning+0x70/0xc0 mm/kmsan/kmsan_instr.c:645
 _decode_session6+0x645/0x1650 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+0x2d01/0x3840 net/ipv6/icmp.c:551
 icmpv6_send+0xe5/0x110 net/ipv6/ip6_icmp.c:43
 ip6_link_failure+0x5c/0x310 net/ipv6/route.c:2255
 dst_link_failure include/net/dst.h:427 [inline]
 ndisc_error_report+0x106/0x1a0 net/ipv6/ndisc.c:695
 neigh_invalidate+0x35b/0x900 net/core/neighbour.c:894
 neigh_timer_handler+0xb72/0x1290 net/core/neighbour.c:980
 call_timer_fn+0x310/0x6c0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xe25/0x1280 kernel/time/timer.c:1682
 run_timer_softirq+0x2e/0x50 kernel/time/timer.c:1695
 __do_softirq+0x614/0xa72 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x20a/0x240 kernel/softirq.c:414
 exiting_irq+0xe/0x10 arch/x86/include/asm/apic.h:536
 smp_apic_timer_interrupt+0x64/0x90 arch/x86/kernel/apic/apic.c:1059
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:869
 </IRQ>
RIP: 0010:kmsan_set_origin_inline+0x6/0x120 mm/kmsan/kmsan_instr.c:529
Code: 00 00 00 00 eb fe 0f 0b 66 90 66 2e 0f 1f 84 00 00 00 00 00 eb fe 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 57 <41> 56 41 55 41 54 53 41 89 f7 49 89 fe 44 89 f0 83 e0 03 41 01 c7
RSP: 0018:ffff8801603bf9c8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 00000000dfa00052 RBX: 00000000dfa00052 RCX: ffff8801603bfa20
RDX: 00000000dfa00052 RSI: 0000000000000001 RDI: ffff8801603bfbd0
RBP: ffff8801603bf9d0 R08: 0000000000480020 R09: 0000000000000002
R10: 0000000000000000 R11: ffffffff812492c0 R12: 0000000000000246
R13: ffff8801603bfbd1 R14: ffff8801ac5b5880 R15: 0000000000000001
 __msan_poison_alloca+0x173/0x1f0 mm/kmsan/kmsan_instr.c:610
 wait_consider_task+0x102/0x5090 kernel/exit.c:1332
 do_wait_thread kernel/exit.c:1447 [inline]
 do_wait+0x7f7/0xf00 kernel/exit.c:1518
 kernel_wait4+0x348/0x520 kernel/exit.c:1661
 __do_sys_wait4 kernel/exit.c:1673 [inline]
 __se_sys_wait4+0x111/0x280 kernel/exit.c:1669
 __x64_sys_wait4+0x56/0x70 kernel/exit.c:1669
 do_syscall_64+0xb8/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x41137a
Code: 0f 83 1a 17 00 00 c3 66 0f 1f 84 00 00 00 00 00 8b 05 3e 4c 63 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d4 ff ff ff f7
RSP: 002b:0000000000a3fdc8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: ffffffffffffffda RBX: 000000000003ea16 RCX: 000000000041137a
RDX: 0000000040000001 RSI: 0000000000a3fdd0 RDI: ffffffffffffffff
RBP: 00000000000001be R08: 0000000000000001 R09: 0000000000fd9940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000003ea16 R14: 0000000000000036 R15: badc0ffeebadface

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:256 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:181
 kmsan_kmalloc+0x98/0x100 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:2718 [inline]
 __kmalloc_node_track_caller+0xb55/0x1380 mm/slub.c:4351
 __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+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+0x2d01/0x3840 net/ipv6/icmp.c:551
 icmpv6_send+0xe5/0x110 net/ipv6/ip6_icmp.c:43
 ip6_link_failure+0x5c/0x310 net/ipv6/route.c:2255
 dst_link_failure include/net/dst.h:427 [inline]
 ndisc_error_report+0x106/0x1a0 net/ipv6/ndisc.c:695
 neigh_invalidate+0x35b/0x900 net/core/neighbour.c:894
 neigh_timer_handler+0xb72/0x1290 net/core/neighbour.c:980
 call_timer_fn+0x310/0x6c0 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0xe25/0x1280 kernel/time/timer.c:1682
 run_timer_softirq+0x2e/0x50 kernel/time/timer.c:1695
 __do_softirq+0x614/0xa72 kernel/softirq.c:292
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