--- /dev/null
+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 / noltari.git / commitdiff