[PATCH 5.11 529/601] netfilter: nftables_offload: VLAN id needs host byteorder in flow dissector

Greg Kroah-Hartman
2021-05-12T17:56:45Z

From: Pablo Neira Ayuso <pablo@netfilter.org>

[ Upstream commit ff4d90a89d3d4d9814e0a2696509a7d495be4163 ]

The flow dissector representation expects the VLAN id in host byteorder.
Add the NFT_OFFLOAD_F_NETWORK2HOST flag to swap the bytes from nft_cmp.

Fixes: a82055af5959 ("netfilter: nft_payload: add VLAN offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/netfilter/nf_tables_offload.h | 11 +++++-
net/netfilter/nft_cmp.c | 41 +++++++++++++++++++++--
net/netfilter/nft_payload.c | 10 +++---
3 files changed, 55 insertions(+), 7 deletions(-)

diff --git a/include/net/netfilter/nf_tables_offload.h b/include/net/netfilter/nf_tables_offload.h
index b4d080061399..434a6158852f 100644
--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -4,11 +4,16 @@
#include <net/flow_offload.h>
#include <net/netfilter/nf_tables.h>

+enum nft_offload_reg_flags {
+ NFT_OFFLOAD_F_NETWORK2HOST = (1 << 0),
+};
+
struct nft_offload_reg {
u32 key;
u32 len;
u32 base_offset;
u32 offset;
+ u32 flags;
struct nft_data data;
struct nft_data mask;
};
@@ -72,13 +77,17 @@ struct nft_flow_rule *nft_flow_rule_create(struct net *net, const struct nft_rul
void nft_flow_rule_destroy(struct nft_flow_rule *flow);
int nft_flow_rule_offload_commit(struct net *net);

-#define NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg) \
+#define NFT_OFFLOAD_MATCH_FLAGS(__key, __base, __field, __len, __reg, __flags) \
(__reg)->base_offset = \
offsetof(struct nft_flow_key, __base); \
(__reg)->offset = \
offsetof(struct nft_flow_key, __base.__field); \
(__reg)->len = __len; \
(__reg)->key = __key; \
+ (__reg)->flags = __flags;
+
+#define NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg) \
+ NFT_OFFLOAD_MATCH_FLAGS(__key, __base, __field, __len, __reg, 0)

#define NFT_OFFLOAD_MATCH_EXACT(__key, __base, __field, __len, __reg) \
NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg) \
diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c
index 00e563a72d3d..1d42d06f5b64 100644
--- a/net/netfilter/nft_cmp.c
+++ b/net/netfilter/nft_cmp.c
@@ -115,19 +115,56 @@ nla_put_failure:
return -1;
}

+union nft_cmp_offload_data {
+ u16 val16;
+ u32 val32;
+ u64 val64;
+};
+
+static void nft_payload_n2h(union nft_cmp_offload_data *data,
+ const u8 *val, u32 len)
+{
+ switch (len) {
+ case 2:
+ data->val16 = ntohs(*((u16 *)val));
+ break;
+ case 4:
+ data->val32 = ntohl(*((u32 *)val));
+ break;
+ case 8:
+ data->val64 = be64_to_cpu(*((u64 *)val));
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ break;
+ }
+}
+
static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
struct nft_flow_rule *flow,
const struct nft_cmp_expr *priv)
{
struct nft_offload_reg *reg = &ctx->regs[priv->sreg];
+ union nft_cmp_offload_data _data, _datamask;
u8 *mask = (u8 *)&flow->match.mask;
u8 *key = (u8 *)&flow->match.key;
+ u8 *data, *datamask;

if (priv->op != NFT_CMP_EQ || priv->len > reg->len)
return -EOPNOTSUPP;

- memcpy(key + reg->offset, &priv->data, reg->len);
- memcpy(mask + reg->offset, &reg->mask, reg->len);
+ if (reg->flags & NFT_OFFLOAD_F_NETWORK2HOST) {
+ nft_payload_n2h(&_data, (u8 *)&priv->data, reg->len);
+ nft_payload_n2h(&_datamask, (u8 *)&reg->mask, reg->len);
+ data = (u8 *)&_data;
+ datamask = (u8 *)&_datamask;
+ } else {
+ data = (u8 *)&priv->data;
+ datamask = (u8 *)&reg->mask;
+ }
+
+ memcpy(key + reg->offset, data, reg->len);
+ memcpy(mask + reg->offset, datamask, reg->len);

flow->match.dissector.used_keys |= BIT(reg->key);
flow->match.dissector.offset[reg->key] = reg->base_offset;
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index e43863a1761f..1ebee25de677 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -226,8 +226,9 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;

- NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
- vlan_tci, sizeof(__be16), reg);
+ NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_VLAN, vlan,
+ vlan_tci, sizeof(__be16), reg,
+ NFT_OFFLOAD_F_NETWORK2HOST);
break;
case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
@@ -241,8 +242,9 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;

- NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
- vlan_tci, sizeof(__be16), reg);
+ NFT_OFFLOAD_MATCH_FLAGS(FLOW_DISSECTOR_KEY_CVLAN, cvlan,
+ vlan_tci, sizeof(__be16), reg,
+ NFT_OFFLOAD_F_NETWORK2HOST);
break;
case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
sizeof(struct vlan_hdr):
--
2.30.2