CVE-2026-80838

In the Linux kernel, the following vulnerability has been resolved: vxlan: keep the last remote linked during FDB flush A non-nexthop FDB entry is expected to have at least one remote while it remains reachable through the FDB hash table. A filtered bulk flush violates this invariant when every remote matches: It unlinks the last remote in vxlan_fdb_dst_destroy() and only afterwards tells vxlan_flush() to destroy the parent FDB entry. An RCU reader can find the parent during this interval. first_remote_rcu() then applies list_entry_rcu() to the empty list head, producing an invalid remote pointer that the receive learning path can read from and write to. When a matching remote is the sole remaining remote, leave it linked and ask the caller to destroy the entire FDB entry. vxlan_fdb_destroy() keeps the remote attached while sending the deletion notification and removing the parent from the lookup structures.

CVSS

No CVSS.

References

Link	Resource
https://git.kernel.org/stable/c/2a7c2f00843225d5f037676bca649321f3d024c7
https://git.kernel.org/stable/c/4bbc76ee1b21d3bd045d6d819b2bacd30a6372ab
https://git.kernel.org/stable/c/8ba68fd6cdd1e3c92b92f25c7e48bf7bd51a183c
https://git.kernel.org/stable/c/a8820c8a7718327e96849782033e7c85a0f6bcfe
https://git.kernel.org/stable/c/d5d4a7b538b52db63927773a8905fcd9f78a42e2

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 16:18

Updated : 2026-09-04 16:18

NVD link : CVE-2026-80838

Mitre link : CVE-2026-80838

CVE.ORG link : CVE-2026-80838

JSON object : View

Products Affected

No product.

CWE

No CWE.

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