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BUG: KASAN: slab-out-of-bounds in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: slab-out-of-bounds in atomic_fetch_add_unless include/linux/atomic.h:575 [inline]
BUG: KASAN: slab-out-of-bounds in atomic_add_unless include/linux/atomic.h:597 [inline]
BUG: KASAN: slab-out-of-bounds in dst_hold_safe include/net/dst.h:308 [inline]
BUG: KASAN: slab-out-of-bounds in ip6_hold_safe+0xa7/0x3a0 net/ipv6/route.c:1023
Read of size 4 at addr ffff8880992d8174 by task ksoftirqd/1/16

CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.0.0+ #5
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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 kasan_check_read+0x11/0x20 mm/kasan/common.c:100
 atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
 atomic_fetch_add_unless include/linux/atomic.h:575 [inline]
 atomic_add_unless include/linux/atomic.h:597 [inline]
 dst_hold_safe include/net/dst.h:308 [inline]
 ip6_hold_safe+0xa7/0x3a0 net/ipv6/route.c:1023
 rt6_get_pcpu_route net/ipv6/route.c:1243 [inline]
 ip6_pol_route+0x33d/0xf00 net/ipv6/route.c:1904
 ip6_pol_route_input+0x65/0x80 net/ipv6/route.c:1923
 fib6_rule_lookup+0x128/0x560 net/ipv6/fib6_rules.c:118
 ip6_route_input_lookup+0xb7/0xd0 net/ipv6/route.c:1935
 ip6_route_input+0x5e6/0x9e0 net/ipv6/route.c:2070
 ip6_rcv_finish_core.isra.0+0x174/0x590 net/ipv6/ip6_input.c:63
 ip6_rcv_finish+0x17d/0x320 net/ipv6/ip6_input.c:74
 NF_HOOK include/linux/netfilter.h:289 [inline]
 NF_HOOK include/linux/netfilter.h:283 [inline]
 ipv6_rcv+0x10e/0x420 net/ipv6/ip6_input.c:272
 __netif_receive_skb_one_core+0x115/0x1a0 net/core/dev.c:4973
 __netif_receive_skb+0x2c/0x1c0 net/core/dev.c:5083
 process_backlog+0x206/0x750 net/core/dev.c:5923
 napi_poll net/core/dev.c:6346 [inline]
 net_rx_action+0x4fa/0x1070 net/core/dev.c:6412
 __do_softirq+0x266/0x95a kernel/softirq.c:292
 run_ksoftirqd kernel/softirq.c:654 [inline]
 run_ksoftirqd+0x8e/0x110 kernel/softirq.c:646
 smpboot_thread_fn+0x6ab/0xa10 kernel/smpboot.c:164
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Allocated by task 8372:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:468
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:503
 slab_post_alloc_hook mm/slab.h:440 [inline]
 slab_alloc mm/slab.c:3388 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3548
 dst_alloc+0x10e/0x1d0 net/core/dst.c:105
 ip6_dst_alloc+0x34/0xa0 net/ipv6/route.c:355
 icmp6_dst_alloc+0x1a9/0x660 net/ipv6/route.c:2664
 ndisc_send_skb+0xfc6/0x14a0 net/ipv6/ndisc.c:471
 ndisc_send_ns+0x3a9/0x860 net/ipv6/ndisc.c:633
 addrconf_dad_work+0xb88/0x1150 net/ipv6/addrconf.c:4082
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Freed by task 9:
 save_stack+0x45/0xd0 mm/kasan/common.c:73
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:457
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:465
 __cache_free mm/slab.c:3494 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3754
 dst_destroy+0x2a0/0x3c0 net/core/dst.c:141
 dst_destroy_rcu+0x16/0x19 net/core/dst.c:154
 __rcu_reclaim kernel/rcu/rcu.h:240 [inline]
 rcu_do_batch kernel/rcu/tree.c:2452 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2773 [inline]
 rcu_process_callbacks+0x928/0x1390 kernel/rcu/tree.c:2754
 __do_softirq+0x266/0x95a kernel/softirq.c:292

The buggy address belongs to the object at ffff8880992d8040
 which belongs to the cache ip6_dst_cache of size 224
The buggy address is located 84 bytes to the right of
 224-byte region [ffff8880992d8040, ffff8880992d8120)
The buggy address belongs to the page:
page:ffffea000264b600 count:1 mapcount:0 mapping:ffff88809b5bc040 index:0xffff8880992d8e00
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea00028e5688 ffffea00029f7808 ffff88809b5bc040
raw: ffff8880992d8e00 ffff8880992d8040 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880992d8000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8880992d8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880992d8100: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
                                                             ^
 ffff8880992d8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880992d8200: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
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