kernel/git/stable/linux.git/drivers/net/ovpn, branch linux-7.2.y

ovpn: defer key slot crypto freeing to workqueue

2026-08-09T20:47:57+00:00

Key slots are released through a kref and the existing release path frees the AEAD transforms from an RCU callback. That is not safe for all crypto implementations: crypto_free_aead can sleep, for example when an async or hardware implementation has teardown work to complete. Use queue_rcu_work for key-slot release. This keeps the RCU grace period needed by lockless key-slot readers, but runs the actual crypto teardown from workqueue context where sleeping is allowed. Once the rcu_work callback runs, pre-existing RCU readers are gone, and the final kref put already proves that no transform user remains, so the worker can release the AEAD transforms and free the slot directly. The previous patch drains ovpn_wq during module exit, so queued key-slot teardown work cannot outlive module text. Fixes: 8534731dbf2d ("ovpn: implement packet processing") Signed-off-by: Ralf Lici Signed-off-by: Antonio Quartulli

ovpn: run deferred work on a module-owned workqueue

2026-08-09T20:47:57+00:00

ovpn queues several work items whose callbacks execute module text. These works currently run on the global system workqueues, so module exit has no driver-owned drain point that guarantees the callbacks have fully returned before the module text can be freed. Object references protect the objects used by the callbacks, but they do not prove that a workqueue function has returned. In particular, a worker can drop the final reference that unblocks device teardown while it is still executing ovpn code. Add a module-owned workqueue and queue all ovpn work items on it. During module exit, unregister rtnl and netlink first, flush the workqueue so ordinary ovpn workers finish, run the final RCU barrier, and destroy the workqueue last. This keeps the workqueue available for cleanup work queued from RCU callbacks, while ensuring no ovpn work item can outlive the module text. The per-device delayed keepalive work remains explicitly disabled during netdev teardown (disable_delayed_work_sync in ndo_uninit), since flush_workqueue does not flush delayed work that is still only pending on its timer. Fixes: 3ecfd9349f40 ("ovpn: implement keepalive mechanism") Fixes: 11851cbd60ea ("ovpn: implement TCP transport") Signed-off-by: Ralf Lici Signed-off-by: Antonio Quartulli

ovpn: finish crypto callback cleanup before peer release

2026-08-07T00:12:13+00:00

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. Do not release that peer reference before the callback has finished its own cleanup. 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. Fixes: 8534731dbf2d ("ovpn: implement packet processing") Signed-off-by: Ralf Lici Signed-off-by: Antonio Quartulli

ovpn: fix NULL dereference when killing missing key

2026-08-07T00:12:13+00:00

ovpn_crypto_kill_key assumes both crypto slots are populated and dereferences each slot before checking it. That is not guaranteed: a peer can have only one installed key, and the kill path may be asked to remove a key that is not present. Read each slot once while holding the crypto state lock, check for NULL before looking at key_id, and only replace the slot that actually matches. Fixes: 89d3c0e4612a ("ovpn: kill key and notify userspace in case of IV exhaustion") Signed-off-by: Ralf Lici Signed-off-by: Antonio Quartulli

ovpn: fix incorrect use of rcu_access_pointer()

2026-07-30T09:28:30+00:00

rcu_access_pointer() should only be used to test the value of a pointer, not to dereference it. As it's in a spin_lock_bh() critical section, use rcu_dereference_bh() instead, avoiding an extra rcu_read_lock(). Fixes: f6226ae7a0cd ("ovpn: introduce the ovpn_socket object") Signed-off-by: Qingfang Deng Signed-off-by: Antonio Quartulli

ovpn: ensure TCP vars are initialized first

2026-07-30T09:28:30+00:00

Netlink calls may access TCP global vars (i.e. when attaching a TCP socket), therefore we need to make sure the latters are initialized beforehand. For this reason move the global TCP initialization at the top of the module init function. Fixes: 11851cbd60ea ("ovpn: implement TCP transport") Signed-off-by: Antonio Quartulli

ovpn: disable IPv4 redirects on MP interfaces

2026-07-30T09:28:30+00:00

ovpn_mp_alloc() tried to disable SEND_REDIRECTS on a multipeer interface, but it runs from ovpn_net_init() (->ndo_init), which register_netdevice() invokes before the NETDEV_REGISTER notifier chain. The IPv4 in_device is only created when that notifier reaches inetdev_event() -> inetdev_init(), so __in_dev_get_rtnl() always returned NULL at ndo_init time and the whole redirect-disabling block (both the per-device and the per-netns IPV4_DEVCONF_ALL write) was dead. MP interfaces therefore kept emitting ICMP redirects. Disabling redirects only once is not enough either: the IPv4 in_device is destroyed and recreated when the interface is moved to a different network namespace (NETDEV_UNREGISTER/NETDEV_REGISTER), and the newly created in_device inherits the destination namespace defaults, silently re-enabling SEND_REDIRECTS. Disable redirects from ovpn_net_open() (->ndo_open) instead: it runs every time the interface is brought up, including after the in_device has been recreated, so the setting is always re-applied. This mirrors what wireguard does in wg_open(). RTNL is held on the ndo_open() path, so __in_dev_get_rtnl() is safe. Fixes: 05003b408c20 ("ovpn: implement multi-peer support") Signed-off-by: Antonio Quartulli

ovpn: hash floated peer by transport identity only

2026-07-30T09:28:30+00:00

The by_transp_addr table is keyed on the peer's remote transport address, but the float rehash hashed bind->remote directly, while the two other sites that touch the table build a clean key first: ovpn_peer_add_mp() and the lookup in ovpn_peer_get_by_transp_addr() both hash a sockaddr holding only family/address/port. For a link-local IPv6 peer, bind->remote carries sin6_scope_id (set from ipv6_iface_scope_id() when the endpoint is learned), and that field is folded into the jhash() over sizeof(struct sockaddr_in6). The lookup never sets sin6_scope_id, so after such a peer floats it is rehashed into a scope_id-dependent bucket that lookups (scope_id 0) never visit, making the peer unreachable through the by_transp_addr fallback. ovpn_peer_transp_match() only compares address and port, so the hash was keying on a field the match ignores. sin6_scope_id must stay in bind->remote because the TX path uses it as flowi6_oif, so it cannot just be cleared there. Instead build the hash key from family/address/port only, exactly like ovpn_peer_add_mp() and the lookup, so all three sites agree on the bucket. Fixes: f0281c1d3732 ("ovpn: add support for updating local or remote UDP endpoint") Signed-off-by: Antonio Quartulli

ovpn: zero-initialize sockaddr before learning a floated endpoint

2026-07-30T09:28:30+00:00

ovpn_peer_endpoints_update() builds the new remote endpoint in an on-stack struct sockaddr_storage that is left uninitialized. For IPv4 only sin_family/sin_addr/sin_port are written, leaving the 8-byte sin_zero padding as stack garbage (for IPv6, sin6_flowinfo is left uninitialized likewise). ovpn_peer_reset_sockaddr() -> ovpn_bind_from_sockaddr() then memcpy()s sizeof(struct sockaddr_in)/sizeof(struct sockaddr_in6) bytes - padding included - into bind->remote. That buffer is later hashed with jhash() over the same length to place the peer in the by_transp_addr table, so the garbage padding lands the floated peer in an essentially random bucket. Lockless lookups in ovpn_peer_get_by_transp_addr() build their key from a zero-initialized sockaddr_storage, compute a different bucket and fail to find the peer. This is also a plain use of uninitialized stack memory in jhash(). Build the floated endpoint with a designated initializer so the padding (sin_zero for IPv4, sin6_flowinfo for IPv6) is zeroed as part of the assignment. This keeps the padding out of the by_transp_addr hash key without memset-ing the whole sockaddr_storage on every received packet. Fixes: f0281c1d3732 ("ovpn: add support for updating local or remote UDP endpoint") Signed-off-by: Antonio Quartulli

ovpn: ensure socket is owned by ovpn before deref sk_user_data

2026-07-30T09:28:30+00:00

Some subsystems, like BPF SOCKMAP, set sk_user_data without actually setting the encap_type. For this reason, we must make sure that the type is the one ovpn expects before dereferencing sk_user_data. Failing to do so may lead to out-of-bounds reads. Fixes: f6226ae7a0cd ("ovpn: introduce the ovpn_socket object") Signed-off-by: Antonio Quartulli