ovpn: tcp - don't deref NULL sk_socket member after tcp_close()
Summary
| CVE | CVE-2026-45918 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-27 14:17:06 UTC |
| Updated | 2026-05-27 14:48:03 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
ovpn: tcp - don't deref NULL sk_socket member after tcp_close()
When deleting a peer in case of keepalive expiration, the peer is
removed from the OpenVPN hashtable and is temporary inserted in a
"release list" for further processing.
This happens in:
ovpn_peer_keepalive_work()
unlock_ovpn(release_list)
This processing includes detaching from the socket being used to
talk to this peer, by restoring its original proto and socket
ops/callbacks.
In case of TCP it may happen that, while the peer is sitting in
the release list, userspace decides to close the socket.
This will result in a concurrent execution of:
tcp_close(sk)
__tcp_close(sk)
sock_orphan(sk)
sk_set_socket(sk, NULL)
The last function call will set sk->sk_socket to NULL.
When the releasing routine is resumed, ovpn_tcp_socket_detach()
will attempt to dereference sk->sk_socket to restore its original
ops member. This operation will crash due to sk->sk_socket being NULL.
Fix this race condition by testing-and-accessing
sk->sk_socket atomically under sk->sk_callback_lock. |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 11851cbd60ea1e5abbd97619d69845ead99303d6 f998b2c4bec487063a586695159f9a1856e81c56 git |
Not specified |
| CNA |
Linux |
Linux |
affected 11851cbd60ea1e5abbd97619d69845ead99303d6 b9142cf4e066c825ec68752a7dcaceda700bbe26 git |
Not specified |
| CNA |
Linux |
Linux |
affected 11851cbd60ea1e5abbd97619d69845ead99303d6 94560267d6c41b1ff3fafbab726e3f8a55a6af34 git |
Not specified |
| CNA |
Linux |
Linux |
affected 6.16 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.16 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.14 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.19.4 6.19.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.0 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/94560267d6c41b1ff3fafbab726e3f8a55a6af34 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/f998b2c4bec487063a586695159f9a1856e81c56 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/b9142cf4e066c825ec68752a7dcaceda700bbe26 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.