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BUG: KASAN: global-out-of-bounds in fib6_ifup+0x257/0x2a0 net/ipv6/route.c:4815
Read of size 8 at addr ffffffff9af9f5b0 by task kworker/u32:2/46

CPU: 0 UID: 0 PID: 46 Comm: kworker/u32:2 Not tainted 6.15.0-rc7-syzkaller-00175-g0f8c0258bf04 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: events_unbound linkwatch_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 fib6_ifup+0x257/0x2a0 net/ipv6/route.c:4815
 fib6_clean_node+0x2a4/0x5b0 net/ipv6/ip6_fib.c:2199
 fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2124
 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2172
 fib6_clean_tree+0xd4/0x110 net/ipv6/ip6_fib.c:2252
 __fib6_clean_all+0x107/0x2d0 net/ipv6/ip6_fib.c:2268
 rt6_sync_up+0xc9/0x170 net/ipv6/route.c:4837
 addrconf_notify+0x1709/0x19e0 net/ipv6/addrconf.c:3732
 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2176
 netif_state_change+0x165/0x3b0 net/core/dev.c:1530
 linkwatch_do_dev+0x12b/0x160 net/core/link_watch.c:186
 __linkwatch_run_queue+0x2aa/0x8a0 net/core/link_watch.c:244
 linkwatch_event+0x8f/0xc0 net/core/link_watch.c:304
 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

The buggy address belongs to the variable:
 __key.0+0x30/0x40

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1af9f
flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000002000 ffffea00006be7c8 ffffea00006be7c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffffffff9af9f480: 00 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9
 ffffffff9af9f500: 00 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9
>ffffffff9af9f580: 00 00 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 f9 f9 f9 f9
                                     ^
 ffffffff9af9f600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f9
 ffffffff9af9f680: f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 00 00 f9 f9
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