From 4c88cfcc6738466a33778c346061f7507403276a Mon Sep 17 00:00:00 2001 From: Ralf Lici Date: Wed, 4 Jun 2025 15:11:58 +0200 Subject: [PATCH 1/3] ovpn: propagate socket mark to skb in UDP OpenVPN allows users to configure a FW mark on sockets used to communicate with other peers. The mark is set by means of the `SO_MARK` Linux socket option. However, in the ovpn UDP code path, the socket's `sk_mark` value is currently ignored and it is not propagated to outgoing `skbs`. This commit ensures proper inheritance of the field by setting `skb->mark` to `sk->sk_mark` before handing the `skb` to the network stack for transmission. Fixes: 08857b5ec5d9 ("ovpn: implement basic TX path (UDP)") Reviewed-by: Sabrina Dubroca Signed-off-by: Ralf Lici Link: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg31877.html Signed-off-by: Antonio Quartulli --- drivers/net/ovpn/udp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/ovpn/udp.c b/drivers/net/ovpn/udp.c index bff00946eae2..60435a21f29c 100644 --- a/drivers/net/ovpn/udp.c +++ b/drivers/net/ovpn/udp.c @@ -344,6 +344,7 @@ void ovpn_udp_send_skb(struct ovpn_peer *peer, struct sock *sk, int ret; skb->dev = peer->ovpn->dev; + skb->mark = READ_ONCE(sk->sk_mark); /* no checksum performed at this layer */ skb->ip_summed = CHECKSUM_NONE; From af52020fc5995dd3bcbc91b897daded755564be7 Mon Sep 17 00:00:00 2001 From: Antonio Quartulli Date: Wed, 25 Jun 2025 16:08:11 +0200 Subject: [PATCH 2/3] ovpn: reject unexpected netlink attributes Netlink ops do not expect all attributes to be always set, however this condition is not explicitly coded any where, leading the user to believe that all sent attributes are somewhat processed. Fix this behaviour by introducing explicit checks. For CMD_OVPN_PEER_GET and CMD_OVPN_KEY_GET directly open-code the needed condition in the related ops handlers. While for all other ops use attribute subsets in the ovpn.yaml spec file. Fixes: b7a63391aa98 ("ovpn: add basic netlink support") Reported-by: Ralf Lici Closes: https://github.com/OpenVPN/ovpn-net-next/issues/19 Signed-off-by: Antonio Quartulli --- Documentation/netlink/specs/ovpn.yaml | 153 +++++++++++++++++++++++++- drivers/net/ovpn/netlink-gen.c | 61 +++++++++- drivers/net/ovpn/netlink-gen.h | 6 + drivers/net/ovpn/netlink.c | 51 +++++++-- 4 files changed, 251 insertions(+), 20 deletions(-) diff --git a/Documentation/netlink/specs/ovpn.yaml b/Documentation/netlink/specs/ovpn.yaml index 096c51f0c69a..ba76426a542d 100644 --- a/Documentation/netlink/specs/ovpn.yaml +++ b/Documentation/netlink/specs/ovpn.yaml @@ -160,6 +160,66 @@ attribute-sets: name: link-tx-packets type: uint doc: Number of packets transmitted at the transport level + - + name: peer-new-input + subset-of: peer + attributes: + - + name: id + - + name: remote-ipv4 + - + name: remote-ipv6 + - + name: remote-ipv6-scope-id + - + name: remote-port + - + name: socket + - + name: vpn-ipv4 + - + name: vpn-ipv6 + - + name: local-ipv4 + - + name: local-ipv6 + - + name: keepalive-interval + - + name: keepalive-timeout + - + name: peer-set-input + subset-of: peer + attributes: + - + name: id + - + name: remote-ipv4 + - + name: remote-ipv6 + - + name: remote-ipv6-scope-id + - + name: remote-port + - + name: vpn-ipv4 + - + name: vpn-ipv6 + - + name: local-ipv4 + - + name: local-ipv6 + - + name: keepalive-interval + - + name: keepalive-timeout + - + name: peer-del-input + subset-of: peer + attributes: + - + name: id - name: keyconf attributes: @@ -216,6 +276,33 @@ attribute-sets: obtain the actual cipher IV checks: exact-len: nonce-tail-size + + - + name: keyconf-get + subset-of: keyconf + attributes: + - + name: peer-id + - + name: slot + - + name: key-id + - + name: cipher-alg + - + name: keyconf-swap-input + subset-of: keyconf + attributes: + - + name: peer-id + - + name: keyconf-del-input + subset-of: keyconf + attributes: + - + name: peer-id + - + name: slot - name: ovpn attributes: @@ -235,12 +322,66 @@ attribute-sets: type: nest doc: Peer specific cipher configuration nested-attributes: keyconf + - + name: ovpn-peer-new-input + subset-of: ovpn + attributes: + - + name: ifindex + - + name: peer + nested-attributes: peer-new-input + - + name: ovpn-peer-set-input + subset-of: ovpn + attributes: + - + name: ifindex + - + name: peer + nested-attributes: peer-set-input + - + name: ovpn-peer-del-input + subset-of: ovpn + attributes: + - + name: ifindex + - + name: peer + nested-attributes: peer-del-input + - + name: ovpn-keyconf-get + subset-of: ovpn + attributes: + - + name: ifindex + - + name: keyconf + nested-attributes: keyconf-get + - + name: ovpn-keyconf-swap-input + subset-of: ovpn + attributes: + - + name: ifindex + - + name: keyconf + nested-attributes: keyconf-swap-input + - + name: ovpn-keyconf-del-input + subset-of: ovpn + attributes: + - + name: ifindex + - + name: keyconf + nested-attributes: keyconf-del-input operations: list: - name: peer-new - attribute-set: ovpn + attribute-set: ovpn-peer-new-input flags: [ admin-perm ] doc: Add a remote peer do: @@ -252,7 +393,7 @@ operations: - peer - name: peer-set - attribute-set: ovpn + attribute-set: ovpn-peer-set-input flags: [ admin-perm ] doc: modify a remote peer do: @@ -286,7 +427,7 @@ operations: - peer - name: peer-del - attribute-set: ovpn + attribute-set: ovpn-peer-del-input flags: [ admin-perm ] doc: Delete existing remote peer do: @@ -316,7 +457,7 @@ operations: - keyconf - name: key-get - attribute-set: ovpn + attribute-set: ovpn-keyconf-get flags: [ admin-perm ] doc: Retrieve non-sensitive data about peer key and cipher do: @@ -331,7 +472,7 @@ operations: - keyconf - name: key-swap - attribute-set: ovpn + attribute-set: ovpn-keyconf-swap-input flags: [ admin-perm ] doc: Swap primary and secondary session keys for a specific peer do: @@ -350,7 +491,7 @@ operations: mcgrp: peers - name: key-del - attribute-set: ovpn + attribute-set: ovpn-keyconf-del-input flags: [ admin-perm ] doc: Delete cipher key for a specific peer do: diff --git a/drivers/net/ovpn/netlink-gen.c b/drivers/net/ovpn/netlink-gen.c index 58e1a4342378..14298188c5f1 100644 --- a/drivers/net/ovpn/netlink-gen.c +++ b/drivers/net/ovpn/netlink-gen.c @@ -29,6 +29,22 @@ const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1] = [OVPN_A_KEYCONF_DECRYPT_DIR] = NLA_POLICY_NESTED(ovpn_keydir_nl_policy), }; +const struct nla_policy ovpn_keyconf_del_input_nl_policy[OVPN_A_KEYCONF_SLOT + 1] = { + [OVPN_A_KEYCONF_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_keyconf_peer_id_range), + [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1), +}; + +const struct nla_policy ovpn_keyconf_get_nl_policy[OVPN_A_KEYCONF_CIPHER_ALG + 1] = { + [OVPN_A_KEYCONF_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_keyconf_peer_id_range), + [OVPN_A_KEYCONF_SLOT] = NLA_POLICY_MAX(NLA_U32, 1), + [OVPN_A_KEYCONF_KEY_ID] = NLA_POLICY_MAX(NLA_U32, 7), + [OVPN_A_KEYCONF_CIPHER_ALG] = NLA_POLICY_MAX(NLA_U32, 2), +}; + +const struct nla_policy ovpn_keyconf_swap_input_nl_policy[OVPN_A_KEYCONF_PEER_ID + 1] = { + [OVPN_A_KEYCONF_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_keyconf_peer_id_range), +}; + const struct nla_policy ovpn_keydir_nl_policy[OVPN_A_KEYDIR_NONCE_TAIL + 1] = { [OVPN_A_KEYDIR_CIPHER_KEY] = NLA_POLICY_MAX_LEN(256), [OVPN_A_KEYDIR_NONCE_TAIL] = NLA_POLICY_EXACT_LEN(OVPN_NONCE_TAIL_SIZE), @@ -60,16 +76,49 @@ const struct nla_policy ovpn_peer_nl_policy[OVPN_A_PEER_LINK_TX_PACKETS + 1] = { [OVPN_A_PEER_LINK_TX_PACKETS] = { .type = NLA_UINT, }, }; +const struct nla_policy ovpn_peer_del_input_nl_policy[OVPN_A_PEER_ID + 1] = { + [OVPN_A_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_peer_id_range), +}; + +const struct nla_policy ovpn_peer_new_input_nl_policy[OVPN_A_PEER_KEEPALIVE_TIMEOUT + 1] = { + [OVPN_A_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_peer_id_range), + [OVPN_A_PEER_REMOTE_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_REMOTE_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID] = { .type = NLA_U32, }, + [OVPN_A_PEER_REMOTE_PORT] = NLA_POLICY_MIN(NLA_BE16, 1), + [OVPN_A_PEER_SOCKET] = { .type = NLA_U32, }, + [OVPN_A_PEER_VPN_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_VPN_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_LOCAL_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_LOCAL_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_KEEPALIVE_INTERVAL] = { .type = NLA_U32, }, + [OVPN_A_PEER_KEEPALIVE_TIMEOUT] = { .type = NLA_U32, }, +}; + +const struct nla_policy ovpn_peer_set_input_nl_policy[OVPN_A_PEER_KEEPALIVE_TIMEOUT + 1] = { + [OVPN_A_PEER_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &ovpn_a_peer_id_range), + [OVPN_A_PEER_REMOTE_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_REMOTE_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_REMOTE_IPV6_SCOPE_ID] = { .type = NLA_U32, }, + [OVPN_A_PEER_REMOTE_PORT] = NLA_POLICY_MIN(NLA_BE16, 1), + [OVPN_A_PEER_VPN_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_VPN_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_LOCAL_IPV4] = { .type = NLA_BE32, }, + [OVPN_A_PEER_LOCAL_IPV6] = NLA_POLICY_EXACT_LEN(16), + [OVPN_A_PEER_KEEPALIVE_INTERVAL] = { .type = NLA_U32, }, + [OVPN_A_PEER_KEEPALIVE_TIMEOUT] = { .type = NLA_U32, }, +}; + /* OVPN_CMD_PEER_NEW - do */ static const struct nla_policy ovpn_peer_new_nl_policy[OVPN_A_PEER + 1] = { [OVPN_A_IFINDEX] = { .type = NLA_U32, }, - [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_new_input_nl_policy), }; /* OVPN_CMD_PEER_SET - do */ static const struct nla_policy ovpn_peer_set_nl_policy[OVPN_A_PEER + 1] = { [OVPN_A_IFINDEX] = { .type = NLA_U32, }, - [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_set_input_nl_policy), }; /* OVPN_CMD_PEER_GET - do */ @@ -86,7 +135,7 @@ static const struct nla_policy ovpn_peer_get_dump_nl_policy[OVPN_A_IFINDEX + 1] /* OVPN_CMD_PEER_DEL - do */ static const struct nla_policy ovpn_peer_del_nl_policy[OVPN_A_PEER + 1] = { [OVPN_A_IFINDEX] = { .type = NLA_U32, }, - [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_nl_policy), + [OVPN_A_PEER] = NLA_POLICY_NESTED(ovpn_peer_del_input_nl_policy), }; /* OVPN_CMD_KEY_NEW - do */ @@ -98,19 +147,19 @@ static const struct nla_policy ovpn_key_new_nl_policy[OVPN_A_KEYCONF + 1] = { /* OVPN_CMD_KEY_GET - do */ static const struct nla_policy ovpn_key_get_nl_policy[OVPN_A_KEYCONF + 1] = { [OVPN_A_IFINDEX] = { .type = NLA_U32, }, - [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_get_nl_policy), }; /* OVPN_CMD_KEY_SWAP - do */ static const struct nla_policy ovpn_key_swap_nl_policy[OVPN_A_KEYCONF + 1] = { [OVPN_A_IFINDEX] = { .type = NLA_U32, }, - [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_swap_input_nl_policy), }; /* OVPN_CMD_KEY_DEL - do */ static const struct nla_policy ovpn_key_del_nl_policy[OVPN_A_KEYCONF + 1] = { [OVPN_A_IFINDEX] = { .type = NLA_U32, }, - [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_nl_policy), + [OVPN_A_KEYCONF] = NLA_POLICY_NESTED(ovpn_keyconf_del_input_nl_policy), }; /* Ops table for ovpn */ diff --git a/drivers/net/ovpn/netlink-gen.h b/drivers/net/ovpn/netlink-gen.h index 66a4e4a0a055..220b5b2fdd4f 100644 --- a/drivers/net/ovpn/netlink-gen.h +++ b/drivers/net/ovpn/netlink-gen.h @@ -13,8 +13,14 @@ /* Common nested types */ extern const struct nla_policy ovpn_keyconf_nl_policy[OVPN_A_KEYCONF_DECRYPT_DIR + 1]; +extern const struct nla_policy ovpn_keyconf_del_input_nl_policy[OVPN_A_KEYCONF_SLOT + 1]; +extern const struct nla_policy ovpn_keyconf_get_nl_policy[OVPN_A_KEYCONF_CIPHER_ALG + 1]; +extern const struct nla_policy ovpn_keyconf_swap_input_nl_policy[OVPN_A_KEYCONF_PEER_ID + 1]; extern const struct nla_policy ovpn_keydir_nl_policy[OVPN_A_KEYDIR_NONCE_TAIL + 1]; extern const struct nla_policy ovpn_peer_nl_policy[OVPN_A_PEER_LINK_TX_PACKETS + 1]; +extern const struct nla_policy ovpn_peer_del_input_nl_policy[OVPN_A_PEER_ID + 1]; +extern const struct nla_policy ovpn_peer_new_input_nl_policy[OVPN_A_PEER_KEEPALIVE_TIMEOUT + 1]; +extern const struct nla_policy ovpn_peer_set_input_nl_policy[OVPN_A_PEER_KEEPALIVE_TIMEOUT + 1]; int ovpn_nl_pre_doit(const struct genl_split_ops *ops, struct sk_buff *skb, struct genl_info *info); diff --git a/drivers/net/ovpn/netlink.c b/drivers/net/ovpn/netlink.c index a4ec53def46e..c7f382437630 100644 --- a/drivers/net/ovpn/netlink.c +++ b/drivers/net/ovpn/netlink.c @@ -352,7 +352,7 @@ int ovpn_nl_peer_new_doit(struct sk_buff *skb, struct genl_info *info) return -EINVAL; ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER], - ovpn_peer_nl_policy, info->extack); + ovpn_peer_new_input_nl_policy, info->extack); if (ret) return ret; @@ -476,7 +476,7 @@ int ovpn_nl_peer_set_doit(struct sk_buff *skb, struct genl_info *info) return -EINVAL; ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER], - ovpn_peer_nl_policy, info->extack); + ovpn_peer_set_input_nl_policy, info->extack); if (ret) return ret; @@ -654,7 +654,7 @@ int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info) struct ovpn_peer *peer; struct sk_buff *msg; u32 peer_id; - int ret; + int ret, i; if (GENL_REQ_ATTR_CHECK(info, OVPN_A_PEER)) return -EINVAL; @@ -668,6 +668,23 @@ int ovpn_nl_peer_get_doit(struct sk_buff *skb, struct genl_info *info) OVPN_A_PEER_ID)) return -EINVAL; + /* OVPN_CMD_PEER_GET expects only the PEER_ID, therefore + * ensure that the user hasn't specified any other attribute. + * + * Unfortunately this check cannot be performed via netlink + * spec/policy and must be open-coded. + */ + for (i = 0; i < OVPN_A_PEER_MAX + 1; i++) { + if (i == OVPN_A_PEER_ID) + continue; + + if (attrs[i]) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "unexpected attribute %u", i); + return -EINVAL; + } + } + peer_id = nla_get_u32(attrs[OVPN_A_PEER_ID]); peer = ovpn_peer_get_by_id(ovpn, peer_id); if (!peer) { @@ -768,7 +785,7 @@ int ovpn_nl_peer_del_doit(struct sk_buff *skb, struct genl_info *info) return -EINVAL; ret = nla_parse_nested(attrs, OVPN_A_PEER_MAX, info->attrs[OVPN_A_PEER], - ovpn_peer_nl_policy, info->extack); + ovpn_peer_del_input_nl_policy, info->extack); if (ret) return ret; @@ -969,14 +986,14 @@ int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info) struct ovpn_peer *peer; struct sk_buff *msg; u32 peer_id; - int ret; + int ret, i; if (GENL_REQ_ATTR_CHECK(info, OVPN_A_KEYCONF)) return -EINVAL; ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, info->attrs[OVPN_A_KEYCONF], - ovpn_keyconf_nl_policy, info->extack); + ovpn_keyconf_get_nl_policy, info->extack); if (ret) return ret; @@ -988,6 +1005,24 @@ int ovpn_nl_key_get_doit(struct sk_buff *skb, struct genl_info *info) OVPN_A_KEYCONF_SLOT)) return -EINVAL; + /* OVPN_CMD_KEY_GET expects only the PEER_ID and the SLOT, therefore + * ensure that the user hasn't specified any other attribute. + * + * Unfortunately this check cannot be performed via netlink + * spec/policy and must be open-coded. + */ + for (i = 0; i < OVPN_A_KEYCONF_MAX + 1; i++) { + if (i == OVPN_A_KEYCONF_PEER_ID || + i == OVPN_A_KEYCONF_SLOT) + continue; + + if (attrs[i]) { + NL_SET_ERR_MSG_FMT_MOD(info->extack, + "unexpected attribute %u", i); + return -EINVAL; + } + } + peer_id = nla_get_u32(attrs[OVPN_A_KEYCONF_PEER_ID]); peer = ovpn_peer_get_by_id(ovpn, peer_id); if (!peer) { @@ -1037,7 +1072,7 @@ int ovpn_nl_key_swap_doit(struct sk_buff *skb, struct genl_info *info) ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, info->attrs[OVPN_A_KEYCONF], - ovpn_keyconf_nl_policy, info->extack); + ovpn_keyconf_swap_input_nl_policy, info->extack); if (ret) return ret; @@ -1074,7 +1109,7 @@ int ovpn_nl_key_del_doit(struct sk_buff *skb, struct genl_info *info) ret = nla_parse_nested(attrs, OVPN_A_KEYCONF_MAX, info->attrs[OVPN_A_KEYCONF], - ovpn_keyconf_nl_policy, info->extack); + ovpn_keyconf_del_input_nl_policy, info->extack); if (ret) return ret; From 2022d704014d7a5b19dfe0a1ae5c67be0498e37c Mon Sep 17 00:00:00 2001 From: Ralf Lici Date: Tue, 1 Jul 2025 14:47:44 +0200 Subject: [PATCH 3/3] ovpn: reset GSO metadata after decapsulation The ovpn_netdev_write() function is responsible for injecting decapsulated and decrypted packets back into the local network stack. Prior to this patch, the skb could retain GSO metadata from the outer, encrypted tunnel packet. This original GSO metadata, relevant to the sender's transport context, becomes invalid and misleading for the tunnel/data path once the inner packet is exposed. Leaving this stale metadata intact causes internal GSO validation checks further down the kernel's network stack (validate_xmit_skb()) to fail, leading to packet drops. The reasons for these failures vary by protocol, for example: - for ICMP, no offload handler is registered; - for TCP and UDP, the respective offload handlers return errors when comparing skb->len to the outdated skb_shinfo(skb)->gso_size. By calling skb_gso_reset(skb) we ensure the inner packet is presented to gro_cells_receive() with a clean state, correctly indicating it is an individual packet from the perspective of the local stack. This change eliminates the "Driver has suspect GRO implementation, TCP performance may be compromised" warning and improves overall TCP performance by allowing GSO/GRO to function as intended on the decapsulated traffic. Fixes: 11851cbd60ea ("ovpn: implement TCP transport") Reported-by: Gert Doering Closes: https://github.com/OpenVPN/ovpn-net-next/issues/4 Tested-by: Gert Doering Signed-off-by: Ralf Lici Signed-off-by: Antonio Quartulli --- drivers/net/ovpn/io.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/ovpn/io.c b/drivers/net/ovpn/io.c index ebf1e849506b..3e9e7f8444b3 100644 --- a/drivers/net/ovpn/io.c +++ b/drivers/net/ovpn/io.c @@ -62,6 +62,13 @@ static void ovpn_netdev_write(struct ovpn_peer *peer, struct sk_buff *skb) unsigned int pkt_len; int ret; + /* + * GSO state from the transport layer is not valid for the tunnel/data + * path. Reset all GSO fields to prevent any further GSO processing + * from entering an inconsistent state. + */ + skb_gso_reset(skb); + /* we can't guarantee the packet wasn't corrupted before entering the * VPN, therefore we give other layers a chance to check that */