CVE-2026-100071

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

net: hsr: free learned nodes on device setup failure

hsr_dev_finalize() can fail after a lower-device RX handler has

already been registered (slave A is added before the failable slave B

and interlink adds). RX handlers run in softirq regardless of the

master's state, so frames received in that window can learn dynamic

nodes into node_db, and the error unwind never releases them.

Free both owned dynamic databases in the unwind, mirroring

hsr_dellink(). proxy_node_db is provably empty on every current error

exit (only interlink RX feeds it, and the interlink add is the last

failable step) and is freed for symmetry. The order is safe:

hsr_del_port() unregisters each RX handler with synchronize_net()

before hsr_del_nodes() runs, which removes remaining entries with

list_del_rcu() and defers their release with call_rcu() for readers

already under RCU.

/// Remediation

Check the references section for vendor advisories and patches from linux. Update linux_kernel to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// Affected products

/// References