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

Status: upstream: reported on 2026/08/29 09:52
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+2aeee973408e81988d90@syzkaller.appspotmail.com
First crash: 21d, last: 6d05h
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ID Workflow Result Correct Bug Created Started Finished Revision
9fbf8f72 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ BUG: Address NUM::NUM on device lo is missing its host route. 2026/08/21 00:00 2026/08/21 00:00 2026/08/21 00:59 1e72964b
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Title Replies (including bot) Last reply
[syzbot] BUG: Address NUM::NUM on device lo is missing its host route. 0 (1) 2026/08/29 09:52
▶ ▼ Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 BUG: Address NUM::NUM on device lo is missing its host route. -1 1 34d 34d 0/2 upstream: reported on 2026/08/05 22:54

Sample crash report:
IPv6: BUG: Address 2001::1 on device lo is missing its host route.
netdevsim netdevsim5 netdevsim3 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim5 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 netdevsim2 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim5 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 netdevsim1 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim5 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 netdevsim0 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim5 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
bridge_slave_1: left allmulticast mode
bridge_slave_1: left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_0: left allmulticast mode
bridge_slave_0: left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): (slave batadv0): Releasing backup interface
bond0 (unregistering): Released all slaves
bond1 (unregistering): Released all slaves
tipc: Disabling bearer <udp:syz2>
tipc: Left network mode
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
netdevsim netdevsim6 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim6 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim6 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim6 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim3 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim3 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim2 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim3 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim1 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim3 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim0 (unregistering): unset [0, 0] type 1 family 0 port 8472 - 0
netdevsim netdevsim3 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0
bridge_slave_1: left allmulticast mode
bridge_slave_1: left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_0: left allmulticast mode
bridge_slave_0: left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
bridge_slave_1: left allmulticast mode
bridge_slave_1: left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_0: left allmulticast mode
bridge_slave_0: left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
pimreg: left allmulticast mode
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond_slave_0: left allmulticast mode
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond_slave_1: left allmulticast mode
bond0 (unregistering): Released all slaves
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): Released all slaves
bond1 (unregistering): Released all slaves
bond2 (unregistering): Released all slaves
tipc: Disabling bearer <udp:syz2>
tipc: Left network mode
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed

Crashes (12):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/02 20:28 upstream 89a312991dc6 74e93e68 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: Address NUM::NUM on device lo is missing its host route.
2026/09/02 04:53 upstream 89a312991dc6 587f6b29 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: Address NUM::NUM on device lo is missing its host route.
2026/09/02 19:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 85995287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/31 17:54 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 316d9396 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/31 11:31 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/31 01:40 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/29 10:00 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/29 09:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/27 21:29 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/27 18:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci f1b8fa82cab7 e2fa417d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/19 01:08 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
2026/08/19 01:08 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 21d6ac051080 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: Address NUM::NUM on device lo is missing its host route.
* Struck through repros no longer work on HEAD.