Medium [CVE-2026-80519] finish crypto callback cleanup before peer release

In the Linux kernel, the following vulnerability has been resolved: ovpn: finish crypto callback cleanup before peer release Crypto completion callbacks hold both key-slot and peer references. The peer reference pins the netdev, and dropping the last peer reference can let netdev unregistration and module removal make progress.

If ovpn_crypto_key_slot_put runs after ovpn_peer_put, it can schedule an RCU callback backed by module text after ovpn_cleanup rcu_barrier has already run. The TX error path also freed the remaining skb after ovpn_peer_put, leaving callback cleanup outside the peer/netdev lifetime window.

Release the key slot and free any remaining skb first, then drop the peer reference as the last callback action. Specifically, within the OpenVPN (OVPN) module's crypto completion callback mechanism, a timing issue exists.

This vulnerability arises when peer references are released prematurely, before the associated cleanup operations are complete. An attacker could potentially exploit this to trigger a use-after-free condition, leading to system instability or a denial of service (DoS).

Red Hat severity: Moderate — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-825.

Red Hat lists Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9 as not affected.