Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f before 2a7c2f00843225d5f037676bca649321f3d024c7; affected c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f before a8820c8a7718327e96849782033e7c85a0f6bcfe; affected c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f before 8ba68fd6cdd1e3c92b92f25c7e48bf7bd51a183c; affected c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f before 4bbc76ee1b21d3bd045d6d819b2bacd30a6372ab; affected c499fccb71cb85902b5c5b9ce9c9ae6683e54a8f before d5d4a7b538b52db63927773a8905fcd9f78a42e2 |
| Linux / Linux | affected 6.7; unaffected 0 before 6.7; unaffected 6.12.108 through 6.12.*; unaffected 6.18.49 through 6.18.*; unaffected 7.1.13 through 7.1.*; unaffected 7.2.3 through 7.2.*; unaffected 7.3 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/2a7c2f00843225d5f037676bca649321f3d024c7
- https://git.kernel.org/stable/c/a8820c8a7718327e96849782033e7c85a0f6bcfe
- https://git.kernel.org/stable/c/8ba68fd6cdd1e3c92b92f25c7e48bf7bd51a183c
- https://git.kernel.org/stable/c/4bbc76ee1b21d3bd045d6d819b2bacd30a6372ab
- https://git.kernel.org/stable/c/d5d4a7b538b52db63927773a8905fcd9f78a42e2