Userspace might match on prefix bytes of header fields if they are on
the byte boundary, this requires that the mask is adjusted accordingly.
Use NFT_OFFLOAD_MATCH_EXACT() for meta since prefix byte matching is not
allowed for this type of selector.
Fixes: c9626a2cbdb2 ("netfilter: nf_tables: add hardware offload support")
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
v2: fix sparse warning.
include/net/netfilter/nf_tables_offload.h | 3 ++
net/netfilter/nft_cmp.c | 8 +--
net/netfilter/nft_meta.c | 16 +++---
net/netfilter/nft_payload.c | 66 +++++++++++++++++------
4 files changed, 64 insertions(+), 29 deletions(-)
diff --git a/include/net/netfilter/nf_tables_offload.h b/include/net/netfilter/nf_tables_offload.h
index bddd34c5bd79..1d34fe154fe0 100644
--- a/include/net/netfilter/nf_tables_offload.h
+++ b/include/net/netfilter/nf_tables_offload.h
@@ -78,6 +78,9 @@ int nft_flow_rule_offload_commit(struct net *net);
offsetof(struct nft_flow_key, __base.__field); \
(__reg)->len = __len; \
(__reg)->key = __key; \
+
+#define NFT_OFFLOAD_MATCH_EXACT(__key, __base, __field, __len, __reg) \
+ NFT_OFFLOAD_MATCH(__key, __base, __field, __len, __reg) \
memset(&(__reg)->mask, 0xff, (__reg)->len);
int nft_chain_offload_priority(struct nft_base_chain *basechain);
diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c
index bc079d68a536..00e563a72d3d 100644
--- a/net/netfilter/nft_cmp.c
+++ b/net/netfilter/nft_cmp.c
@@ -123,11 +123,11 @@ static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
u8 *mask = (u8 *)&flow->match.mask;
u8 *key = (u8 *)&flow->match.key;
- if (priv->op != NFT_CMP_EQ || reg->len != priv->len)
+ if (priv->op != NFT_CMP_EQ || priv->len > reg->len)
return -EOPNOTSUPP;
- memcpy(key + reg->offset, &priv->data, priv->len);
- memcpy(mask + reg->offset, ®->mask, priv->len);
+ memcpy(key + reg->offset, &priv->data, reg->len);
+ memcpy(mask + reg->offset, ®->mask, reg->len);
flow->match.dissector.used_keys |= BIT(reg->key);
flow->match.dissector.offset[reg->key] = reg->base_offset;
@@ -137,7 +137,7 @@ static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
nft_reg_load16(priv->data.data) != ARPHRD_ETHER)
return -EOPNOTSUPP;
- nft_offload_update_dependency(ctx, &priv->data, priv->len);
+ nft_offload_update_dependency(ctx, &priv->data, reg->len);
return 0;
}
diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index b37bd02448d8..bf4b3ad5314c 100644
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -724,22 +724,22 @@ static int nft_meta_get_offload(struct nft_offload_ctx *ctx,
switch (priv->key) {
case NFT_META_PROTOCOL:
- NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
- sizeof(__u16), reg);
+ NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, n_proto,
+ sizeof(__u16), reg);
nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
break;
case NFT_META_L4PROTO:
- NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
- sizeof(__u8), reg);
+ NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
+ sizeof(__u8), reg);
nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT);
break;
case NFT_META_IIF:
- NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_META, meta,
- ingress_ifindex, sizeof(__u32), reg);
+ NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
+ ingress_ifindex, sizeof(__u32), reg);
break;
case NFT_META_IIFTYPE:
- NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_META, meta,
- ingress_iftype, sizeof(__u16), reg);
+ NFT_OFFLOAD_MATCH_EXACT(FLOW_DISSECTOR_KEY_META, meta,
+ ingress_iftype, sizeof(__u16), reg);
break;
default:
return -EOPNOTSUPP;
diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c
index bbf811d030d5..47d4e0e21651 100644
--- a/net/netfilter/nft_payload.c
+++ b/net/netfilter/nft_payload.c
@@ -165,6 +165,34 @@ static int nft_payload_dump(struct sk_buff *skb, const struct nft_expr *expr)
return -1;
}
+static bool nft_payload_offload_mask(struct nft_offload_reg *reg,
+ u32 priv_len, u32 field_len)
+{
+ unsigned int remainder, delta, k;
+ struct nft_data mask = {};
+ __be32 remainder_mask;
+
+ if (priv_len == field_len) {
+ memset(®->mask, 0xff, priv_len);
+ return true;
+ } else if (priv_len > field_len) {
+ return false;
+ }
+
+ memset(&mask, 0xff, field_len);
+ remainder = priv_len % sizeof(u32);
+ if (remainder) {
+ k = priv_len / sizeof(u32);
+ delta = field_len - priv_len;
+ remainder_mask = htonl(~((1 << (delta * BITS_PER_BYTE)) - 1));
+ mask.data[k] = (__force u32)remainder_mask;
+ }
+
+ memcpy(®->mask, &mask, field_len);
+
+ return true;
+}
+
static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
struct nft_flow_rule *flow,
const struct nft_payload *priv)
@@ -173,21 +201,21 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
switch (priv->offset) {
case offsetof(struct ethhdr, h_source):
- if (priv->len != ETH_ALEN)
+ if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
src, ETH_ALEN, reg);
break;
case offsetof(struct ethhdr, h_dest):
- if (priv->len != ETH_ALEN)
+ if (!nft_payload_offload_mask(reg, priv->len, ETH_ALEN))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs,
dst, ETH_ALEN, reg);
break;
case offsetof(struct ethhdr, h_proto):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic,
@@ -195,14 +223,14 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
break;
case offsetof(struct vlan_ethhdr, h_vlan_TCI):
- if (priv->len != sizeof(__be16))
+ 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);
break;
case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_VLAN, vlan,
@@ -210,7 +238,7 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_NETWORK);
break;
case offsetof(struct vlan_ethhdr, h_vlan_TCI) + sizeof(struct vlan_hdr):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
@@ -218,7 +246,7 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx,
break;
case offsetof(struct vlan_ethhdr, h_vlan_encapsulated_proto) +
sizeof(struct vlan_hdr):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_CVLAN, vlan,
@@ -239,7 +267,8 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
switch (priv->offset) {
case offsetof(struct iphdr, saddr):
- if (priv->len != sizeof(struct in_addr))
+ if (!nft_payload_offload_mask(reg, priv->len,
+ sizeof(struct in_addr)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src,
@@ -247,7 +276,8 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
break;
case offsetof(struct iphdr, daddr):
- if (priv->len != sizeof(struct in_addr))
+ if (!nft_payload_offload_mask(reg, priv->len,
+ sizeof(struct in_addr)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst,
@@ -255,7 +285,7 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx,
nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV4_ADDRS);
break;
case offsetof(struct iphdr, protocol):
- if (priv->len != sizeof(__u8))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
@@ -277,7 +307,8 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
switch (priv->offset) {
case offsetof(struct ipv6hdr, saddr):
- if (priv->len != sizeof(struct in6_addr))
+ if (!nft_payload_offload_mask(reg, priv->len,
+ sizeof(struct in6_addr)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src,
@@ -285,7 +316,8 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
break;
case offsetof(struct ipv6hdr, daddr):
- if (priv->len != sizeof(struct in6_addr))
+ if (!nft_payload_offload_mask(reg, priv->len,
+ sizeof(struct in6_addr)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst,
@@ -293,7 +325,7 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx,
nft_flow_rule_set_addr_type(flow, FLOW_DISSECTOR_KEY_IPV6_ADDRS);
break;
case offsetof(struct ipv6hdr, nexthdr):
- if (priv->len != sizeof(__u8))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__u8)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto,
@@ -335,14 +367,14 @@ static int nft_payload_offload_tcp(struct nft_offload_ctx *ctx,
switch (priv->offset) {
case offsetof(struct tcphdr, source):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
sizeof(__be16), reg);
break;
case offsetof(struct tcphdr, dest):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
@@ -363,14 +395,14 @@ static int nft_payload_offload_udp(struct nft_offload_ctx *ctx,
switch (priv->offset) {
case offsetof(struct udphdr, source):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src,
sizeof(__be16), reg);
break;
case offsetof(struct udphdr, dest):
- if (priv->len != sizeof(__be16))
+ if (!nft_payload_offload_mask(reg, priv->len, sizeof(__be16)))
return -EOPNOTSUPP;
NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst,
--
2.20.1
