CVE-2026-64123

HIGH
7.8CVSS v3
CVSS v2
0.13% EPSS (exploit probability)
CWE

Description

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

net: hsr: defer node table free until after RCU readers

HSR node-list and node-status generic-netlink operations run under
rcu_read_lock(). They walk hsr->node_db through hsr_get_next_node() and
hsr_get_node_data(), but RTM_DELLINK teardown removes the same node table
with plain list_del() and frees each node immediately.

That lets a generic-netlink reader hold a struct hsr_node pointer across
hsr_dellink(). In a KASAN build, widening the reader window after
hsr_get_next_node() obtains the node reproduces a slab-use-after-free
when the reader copies node->macaddress_A; the freeing stack is
hsr_del_nodes() from hsr_dellink().

Use list_del_rcu() and defer the free through the existing
hsr_free_node_rcu() callback. This matches the lifetime rule used by the
HSR prune paths, which already delete nodes with list_del_rcu() and
call_rcu().

CVSS v3 vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected routers (0)

No routers currently mapped to this CVE in our database.

External references