vxlan: keep the last remote linked during FDB flush
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.12.108, 6.18.49, 7.1.13, 7.2.3
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
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.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f · fixed in 2a7c2f00843225d5f037676bca649321f3d024c7; From c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f · fixed in a8820c8a7718327e96849782033e7c85a0f6bcfe; From c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f · fixed in 8ba68fd6cdd1e3c92b92f25c7e48bf7bd51a183c; From c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f · fixed in 4bbc76ee1b21d3bd045d6d819b2bacd30a6372ab; From c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f · fixed in d5d4a7b538b52db63927773a8905fcd9f78a42e2
- Linux Linux
6.7
- KernelLinux
From 6.7.0 · fixed in 6.12.108; From 6.13.0 · fixed in 6.18.49; From 6.19.0 · fixed in 7.1.13; From 7.2.0 · fixed in 7.2.3