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

Status: upstream: reported on 2026/08/07 12:56
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+ded267b328e950a7c0c4@syzkaller.appspotmail.com
First crash: 6d05h, last: 1h01m
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ID Workflow Result Correct Bug Created Started Finished Revision
2bf80966 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ✅ VMHostTrigger: ❌ ❓ BUG: Address fc00:: on device lo is missing its host route. 2026/08/09 09:44 2026/08/09 09:44 2026/08/09 10:57 5d63f80b
▶ ▼ Discussions (2)
Title Replies (including bot) Last reply
[PATCH] ipv6: addrconf: drop "BUG: " prefix from pr_warn() 4 (4) 2026/08/10 10:40
[syzbot] BUG: Address fc00:: on device lo is missing its host route. 0 (1) 2026/08/07 12:56
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 BUG: Address fc00:: on device lo is missing its host route. -1 1 5d08h 5d08h 0/2 premoderation: reported on 2026/08/05 17:27
android-6-12 BUG: Address fc00:: on device lo is missing its host route. -1 1 4d18h 4d18h 0/1 premoderation: reported on 2026/08/06 07:35
linux-6.1 BUG: Address fc00:: on device lo is missing its host route. -1 2 3d02h 3d02h 0/3 upstream: reported on 2026/08/07 23:09

Sample crash report:
IPv6: BUG: Address fc00:: on device lo is missing its host route.
nvme nvme0: NVME-FC{0}: create association : host wwpn 0x2222222222222222  rport wwpn 0x4444444444444444: NQN "nqn."
(NULL device *): queue 0 connect admin queue failed (-6).
nvme nvme0: NVME-FC{0}: reset: Reconnect attempt failed (-6)
nvme nvme0: NVME-FC{0}: Reconnect attempt in 2 seconds
nvme nvme0: NVME-FC{0}: create association : host wwpn 0x2222222222222222  rport wwpn 0x4444444444444444: NQN "nqn."
(NULL device *): queue 0 connect admin queue failed (-6).
nvme nvme0: NVME-FC{0}: reset: Reconnect attempt failed (-6)
nvme nvme0: NVME-FC{0}: Reconnect attempt in 2 seconds

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/10 15:19 upstream db2ddb871435 039457bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/10 15:09 upstream db2ddb871435 039457bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/10 10:46 upstream db2ddb871435 558388e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/07 11:41 upstream 364465ab19de e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/07 11:38 upstream 364465ab19de e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/06 01:44 upstream 0d8395707651 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/08 02:58 upstream 3f008280327b 5d63f80b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/08 02:58 upstream 3f008280327b 5d63f80b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/08 02:58 upstream 3f008280327b 5d63f80b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root BUG: Address fc00:: on device lo is missing its host route.
2026/08/11 00:34 upstream d58772d8520c 508909ea .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: Address fc00:: on device lo is missing its host route.
2026/08/07 08:50 upstream fcaeecb8b0cd c38879ea .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: Address fc00:: on device lo is missing its host route.
2026/08/07 08:49 upstream fcaeecb8b0cd c38879ea .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: Address fc00:: on device lo is missing its host route.
2026/08/08 13:32 linux-next cc2b5f627e8c 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce BUG: Address fc00:: on device lo is missing its host route.
2026/08/10 19:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ba5cc80fd326 039457bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address fc00:: on device lo is missing its host route.
2026/08/06 16:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address fc00:: on device lo is missing its host route.
2026/08/04 20:01 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address fc00:: on device lo is missing its host route.
* Struck through repros no longer work on HEAD.