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BUG: KASAN: global-out-of-bounds in fib6_add_rt2node net/ipv6/ip6_fib.c:1096 [inline]
BUG: KASAN: global-out-of-bounds in fib6_add+0xcde/0x4360 net/ipv6/ip6_fib.c:1488
Read of size 8 at addr ffffffff99ce9648 by task syz-executor/8336

CPU: 1 UID: 0 PID: 8336 Comm: syz-executor Not tainted 6.15.0-rc7-syzkaller-00099-g94305e83eccb #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xb4/0x290 mm/kasan/report.c:521
 kasan_report+0x118/0x150 mm/kasan/report.c:634
 fib6_add_rt2node net/ipv6/ip6_fib.c:1096 [inline]
 fib6_add+0xcde/0x4360 net/ipv6/ip6_fib.c:1488
 __ip6_ins_rt net/ipv6/route.c:1351 [inline]
 ip6_route_add+0x8a/0x160 net/ipv6/route.c:3900
 addrconf_prefix_route net/ipv6/addrconf.c:2487 [inline]
 fixup_permanent_addr net/ipv6/addrconf.c:3602 [inline]
 addrconf_permanent_addr+0x67f/0x9d0 net/ipv6/addrconf.c:3626
 addrconf_notify+0x887/0x1010 net/ipv6/addrconf.c:3698
 notifier_call_chain+0x1b3/0x3e0 kernel/notifier.c:85
 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
 call_netdevice_notifiers net/core/dev.c:2228 [inline]
 __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1
 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9422
 do_setlink+0xcb9/0x40d0 net/core/rtnetlink.c:3152
 rtnl_changelink net/core/rtnetlink.c:3769 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3928 [inline]
 rtnl_newlink+0x160b/0x1c70 net/core/rtnetlink.c:4065
 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6955
 netlink_rcv_skb+0x21c/0x490 net/netlink/af_netlink.c:2534
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0x758/0x8d0 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:727
 __sys_sendto+0x3bd/0x520 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2183
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdc1f5907fc
Code: 2a 5f 02 00 44 8b 4c 24 2c 4c 8b 44 24 20 89 c5 44 8b 54 24 28 48 8b 54 24 18 b8 2c 00 00 00 48 8b 74 24 10 8b 7c 24 08 0f 05 <48> 3d 00 f0 ff ff 77 34 89 ef 48 89 44 24 08 e8 70 5f 02 00 48 8b
RSP: 002b:00007ffd7fd9a940 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fdc202e4620 RCX: 00007fdc1f5907fc
RDX: 0000000000000020 RSI: 00007fdc202e4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffd7fd9a994 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fdc202e4670 R15: 0000000000000000
 </TASK>

The buggy address belongs to the variable:
 binder_devices+0x8/0x20

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x19ce9
flags: 0xfff00000002000(reserved|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000002000 ffffea0000673a48 ffffea0000673a48 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:
 ffffffff99ce9500: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffffffff99ce9580: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
>ffffffff99ce9600: f9 f9 f9 f9 f9 f9 f9 f9 00 f9 f9 f9 00 00 f9 f9
                                              ^
 ffffffff99ce9680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffff99ce9700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 04 f9
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