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

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    b126f6f5940f Merge tag 'x86_mm_for_7.3-rc1' of git://git.k..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15d26e79580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=5c9120c514e57ada
dashboard link: https://syzkaller.appspot.com/bug?extid=57f410c9a4f8d7a441d6
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=17ac7815580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-b126f6f5.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/93496da690a1/vmlinux-b126f6f5.xz
kernel image: https://storage.googleapis.com/syzbot-assets/239dcaeff1b9/bzImage-b126f6f5.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+57f410c9a4f8d7a441d6@xxxxxxxxxxxxxxxxxxxxxxxxx

IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.
IPv6: BUG: Address 2001::fb on device lo is missing its host route.


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