-From 0bc01df3df7a88258148518eb9ce7f88c16a6106 Mon Sep 17 00:00:00 2001
-From: Liping Zhang <zlpnobody@gmail.com>
-Date: Wed, 8 Mar 2017 22:54:18 +0800
-Subject: netfilter: nf_tables: fix mismatch in big-endian system
-
-Currently, there are two different methods to store an u16 integer to
-the u32 data register. For example:
- u32 *dest = ®s->data[priv->dreg];
- 1. *dest = 0; *(u16 *) dest = val_u16;
- 2. *dest = val_u16;
-
-For method 1, the u16 value will be stored like this, either in
-big-endian or little-endian system:
- 0 15 31
- +-+-+-+-+-+-+-+-+-+-+-+-+
- | Value | 0 |
- +-+-+-+-+-+-+-+-+-+-+-+-+
-
-For method 2, in little-endian system, the u16 value will be the same
-as listed above. But in big-endian system, the u16 value will be stored
-like this:
- 0 15 31
- +-+-+-+-+-+-+-+-+-+-+-+-+
- | 0 | Value |
- +-+-+-+-+-+-+-+-+-+-+-+-+
-
-So later we use "memcmp(®s->data[priv->sreg], data, 2);" to do
-compare in nft_cmp, nft_lookup expr ..., method 2 will get the wrong
-result in big-endian system, as 0~15 bits will always be zero.
-
-For the similar reason, when loading an u16 value from the u32 data
-register, we should use "*(u16 *) sreg;" instead of "(u16)*sreg;",
-the 2nd method will get the wrong value in the big-endian system.
-
-So introduce some wrapper functions to store/load an u8 or u16
-integer to/from the u32 data register, and use them in the right
-place.
-
-Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
-Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
----
- include/net/netfilter/nf_tables.h | 29 +++++++++++++++++++++++++
- net/ipv4/netfilter/nft_masq_ipv4.c | 8 +++----
- net/ipv4/netfilter/nft_redir_ipv4.c | 8 +++----
- net/ipv6/netfilter/nft_masq_ipv6.c | 8 +++----
- net/ipv6/netfilter/nft_redir_ipv6.c | 8 +++----
- net/netfilter/nft_ct.c | 10 ++++-----
- net/netfilter/nft_meta.c | 42 +++++++++++++++++++------------------
- net/netfilter/nft_nat.c | 8 +++----
- 8 files changed, 76 insertions(+), 45 deletions(-)
-
---- a/include/net/netfilter/nf_tables.h
-+++ b/include/net/netfilter/nf_tables.h
-@@ -87,6 +87,35 @@ struct nft_regs {
- };
- };
-
-+/* Store/load an u16 or u8 integer to/from the u32 data register.
-+ *
-+ * Note, when using concatenations, register allocation happens at 32-bit
-+ * level. So for store instruction, pad the rest part with zero to avoid
-+ * garbage values.
-+ */
-+
-+static inline void nft_reg_store16(u32 *dreg, u16 val)
-+{
-+ *dreg = 0;
-+ *(u16 *)dreg = val;
-+}
-+
-+static inline void nft_reg_store8(u32 *dreg, u8 val)
-+{
-+ *dreg = 0;
-+ *(u8 *)dreg = val;
-+}
-+
-+static inline u16 nft_reg_load16(u32 *sreg)
-+{
-+ return *(u16 *)sreg;
-+}
-+
-+static inline u8 nft_reg_load8(u32 *sreg)
-+{
-+ return *(u8 *)sreg;
-+}
-+
- static inline void nft_data_copy(u32 *dst, const struct nft_data *src,
- unsigned int len)
- {
---- a/net/ipv4/netfilter/nft_masq_ipv4.c
-+++ b/net/ipv4/netfilter/nft_masq_ipv4.c
-@@ -26,10 +26,10 @@ static void nft_masq_ipv4_eval(const str
- memset(&range, 0, sizeof(range));
- range.flags = priv->flags;
- if (priv->sreg_proto_min) {
-- range.min_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_min];
-- range.max_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_max];
-+ range.min_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_min]);
-+ range.max_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_max]);
- }
- regs->verdict.code = nf_nat_masquerade_ipv4(pkt->skb, pkt->hook,
- &range, pkt->out);
---- a/net/ipv4/netfilter/nft_redir_ipv4.c
-+++ b/net/ipv4/netfilter/nft_redir_ipv4.c
-@@ -26,10 +26,10 @@ static void nft_redir_ipv4_eval(const st
-
- memset(&mr, 0, sizeof(mr));
- if (priv->sreg_proto_min) {
-- mr.range[0].min.all =
-- *(__be16 *)®s->data[priv->sreg_proto_min];
-- mr.range[0].max.all =
-- *(__be16 *)®s->data[priv->sreg_proto_max];
-+ mr.range[0].min.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_min]);
-+ mr.range[0].max.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_max]);
- mr.range[0].flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
- }
-
---- a/net/ipv6/netfilter/nft_masq_ipv6.c
-+++ b/net/ipv6/netfilter/nft_masq_ipv6.c
-@@ -27,10 +27,10 @@ static void nft_masq_ipv6_eval(const str
- memset(&range, 0, sizeof(range));
- range.flags = priv->flags;
- if (priv->sreg_proto_min) {
-- range.min_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_min];
-- range.max_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_max];
-+ range.min_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_min]);
-+ range.max_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_max]);
- }
- regs->verdict.code = nf_nat_masquerade_ipv6(pkt->skb, &range, pkt->out);
- }
---- a/net/ipv6/netfilter/nft_redir_ipv6.c
-+++ b/net/ipv6/netfilter/nft_redir_ipv6.c
-@@ -26,10 +26,10 @@ static void nft_redir_ipv6_eval(const st
-
- memset(&range, 0, sizeof(range));
- if (priv->sreg_proto_min) {
-- range.min_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_min],
-- range.max_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_max],
-+ range.min_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_min]);
-+ range.max_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_max]);
- range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
- }
-
---- a/net/netfilter/nft_ct.c
-+++ b/net/netfilter/nft_ct.c
-@@ -77,7 +77,7 @@ static void nft_ct_get_eval(const struct
-
- switch (priv->key) {
- case NFT_CT_DIRECTION:
-- *dest = CTINFO2DIR(ctinfo);
-+ nft_reg_store8(dest, CTINFO2DIR(ctinfo));
- return;
- case NFT_CT_STATUS:
- *dest = ct->status;
-@@ -129,10 +129,10 @@ static void nft_ct_get_eval(const struct
- return;
- }
- case NFT_CT_L3PROTOCOL:
-- *dest = nf_ct_l3num(ct);
-+ nft_reg_store8(dest, nf_ct_l3num(ct));
- return;
- case NFT_CT_PROTOCOL:
-- *dest = nf_ct_protonum(ct);
-+ nft_reg_store8(dest, nf_ct_protonum(ct));
- return;
- default:
- break;
-@@ -149,10 +149,10 @@ static void nft_ct_get_eval(const struct
- nf_ct_l3num(ct) == NFPROTO_IPV4 ? 4 : 16);
- return;
- case NFT_CT_PROTO_SRC:
-- *dest = (__force __u16)tuple->src.u.all;
-+ nft_reg_store16(dest, (__force u16)tuple->src.u.all);
- return;
- case NFT_CT_PROTO_DST:
-- *dest = (__force __u16)tuple->dst.u.all;
-+ nft_reg_store16(dest, (__force u16)tuple->dst.u.all);
- return;
- default:
- break;
---- a/net/netfilter/nft_meta.c
-+++ b/net/netfilter/nft_meta.c
-@@ -45,16 +45,15 @@ void nft_meta_get_eval(const struct nft_
- *dest = skb->len;
- break;
- case NFT_META_PROTOCOL:
-- *dest = 0;
-- *(__be16 *)dest = skb->protocol;
-+ nft_reg_store16(dest, (__force u16)skb->protocol);
- break;
- case NFT_META_NFPROTO:
-- *dest = pkt->pf;
-+ nft_reg_store8(dest, pkt->pf);
- break;
- case NFT_META_L4PROTO:
- if (!pkt->tprot_set)
- goto err;
-- *dest = pkt->tprot;
-+ nft_reg_store8(dest, pkt->tprot);
- break;
- case NFT_META_PRIORITY:
- *dest = skb->priority;
-@@ -85,14 +84,12 @@ void nft_meta_get_eval(const struct nft_
- case NFT_META_IIFTYPE:
- if (in == NULL)
- goto err;
-- *dest = 0;
-- *(u16 *)dest = in->type;
-+ nft_reg_store16(dest, in->type);
- break;
- case NFT_META_OIFTYPE:
- if (out == NULL)
- goto err;
-- *dest = 0;
-- *(u16 *)dest = out->type;
-+ nft_reg_store16(dest, out->type);
- break;
- case NFT_META_SKUID:
- sk = skb_to_full_sk(skb);
-@@ -142,22 +139,22 @@ void nft_meta_get_eval(const struct nft_
- #endif
- case NFT_META_PKTTYPE:
- if (skb->pkt_type != PACKET_LOOPBACK) {
-- *dest = skb->pkt_type;
-+ nft_reg_store8(dest, skb->pkt_type);
- break;
- }
-
- switch (pkt->pf) {
- case NFPROTO_IPV4:
- if (ipv4_is_multicast(ip_hdr(skb)->daddr))
-- *dest = PACKET_MULTICAST;
-+ nft_reg_store8(dest, PACKET_MULTICAST);
- else
-- *dest = PACKET_BROADCAST;
-+ nft_reg_store8(dest, PACKET_BROADCAST);
- break;
- case NFPROTO_IPV6:
- if (ipv6_hdr(skb)->daddr.s6_addr[0] == 0xFF)
-- *dest = PACKET_MULTICAST;
-+ nft_reg_store8(dest, PACKET_MULTICAST);
- else
-- *dest = PACKET_BROADCAST;
-+ nft_reg_store8(dest, PACKET_BROADCAST);
- break;
- case NFPROTO_NETDEV:
- switch (skb->protocol) {
-@@ -171,14 +168,14 @@ void nft_meta_get_eval(const struct nft_
- goto err;
-
- if (ipv4_is_multicast(iph->daddr))
-- *dest = PACKET_MULTICAST;
-+ nft_reg_store8(dest, PACKET_MULTICAST);
- else
-- *dest = PACKET_BROADCAST;
-+ nft_reg_store8(dest, PACKET_BROADCAST);
-
- break;
- }
- case htons(ETH_P_IPV6):
-- *dest = PACKET_MULTICAST;
-+ nft_reg_store8(dest, PACKET_MULTICAST);
- break;
- default:
- WARN_ON_ONCE(1);
-@@ -233,7 +230,9 @@ void nft_meta_set_eval(const struct nft_
- {
- const struct nft_meta *meta = nft_expr_priv(expr);
- struct sk_buff *skb = pkt->skb;
-- u32 value = regs->data[meta->sreg];
-+ u32 *sreg = ®s->data[meta->sreg];
-+ u32 value = *sreg;
-+ u8 pkt_type;
-
- switch (meta->key) {
- case NFT_META_MARK:
-@@ -243,9 +242,12 @@ void nft_meta_set_eval(const struct nft_
- skb->priority = value;
- break;
- case NFT_META_PKTTYPE:
-- if (skb->pkt_type != value &&
-- skb_pkt_type_ok(value) && skb_pkt_type_ok(skb->pkt_type))
-- skb->pkt_type = value;
-+ pkt_type = nft_reg_load8(sreg);
-+
-+ if (skb->pkt_type != pkt_type &&
-+ skb_pkt_type_ok(pkt_type) &&
-+ skb_pkt_type_ok(skb->pkt_type))
-+ skb->pkt_type = pkt_type;
- break;
- case NFT_META_NFTRACE:
- skb->nf_trace = !!value;
---- a/net/netfilter/nft_nat.c
-+++ b/net/netfilter/nft_nat.c
-@@ -65,10 +65,10 @@ static void nft_nat_eval(const struct nf
- }
-
- if (priv->sreg_proto_min) {
-- range.min_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_min];
-- range.max_proto.all =
-- *(__be16 *)®s->data[priv->sreg_proto_max];
-+ range.min_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_min]);
-+ range.max_proto.all = (__force __be16)nft_reg_load16(
-+ ®s->data[priv->sreg_proto_max]);
- range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
- }
-
projects / openwrt / staging / dedeckeh.git / commitdiff