[syzbot] BUG: Address fc00:: on device lo is missing its host route.

Hello,

syzbot found the following issue on:

HEAD commit:    364465ab19de Merge tag 'v7.2-rc6-smb3-server-fixes' of git..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=108402c6580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=acc0a882b963ae23
dashboard link: https://syzkaller.appspot.com/bug?extid=ded267b328e950a7c0c4
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a16108cc17bc/disk-364465ab.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/06f139add938/vmlinux-364465ab.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7d4060230883/bzImage-364465ab.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

IPv6: BUG: Address fc00:: on device lo is missing its host route.
bond9: (slave ip6gretap1): link status up, enabling it in 0 ms
bond9: (slave ip6gretap1): failed to get link speed/duplex
bond9: (slave ip6gretap1): link status up, enabling it in 0 ms
bond9: (slave ip6gretap1): failed to get link speed/duplex
bond9: (slave ip6gretap1): link status up, enabling it in 0 ms
bond9: (slave ip6gretap1): failed to get link speed/duplex
net_ratelimit: 80 callbacks suppressed
bond9: (slave ip6gretap1): link status up, enabling it in 0 ms
bond9: (slave ip6gretap1): failed to get link speed/duplex
bond9: (slave ip6gretap1): link status up, enabling it in 0 ms
bond9: (slave ip6gretap1): failed to get link speed/duplex


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