netfilter: nf_tables: use NLA_POLICY_MASK to test for valid flag options

nf_tables relies on manual test of netlink attributes coming from userspace
even in cases where this could be handled via netlink policy.

Convert a bunch of 'flag' attributes to use NLA_POLICY_MASK checks.

Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/net/netfilter/nft_fib.c b/net/netfilter/nft_fib.c
index 6e049fd..601c9e0 100644 (file)
--- a/net/netfilter/nft_fib.c
+++ b/net/netfilter/nft_fib.c
@@ -14,17 +14,18 @@
 #include <net/netfilter/nf_tables.h>
 #include <net/netfilter/nft_fib.h>
 
+#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR | \
+                       NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF | \
+                       NFTA_FIB_F_PRESENT)
+
 const struct nla_policy nft_fib_policy[NFTA_FIB_MAX + 1] = {
        [NFTA_FIB_DREG]         = { .type = NLA_U32 },
        [NFTA_FIB_RESULT]       = { .type = NLA_U32 },
-       [NFTA_FIB_FLAGS]        = { .type = NLA_U32 },
+       [NFTA_FIB_FLAGS]        =
+               NLA_POLICY_MASK(NLA_BE32, NFTA_FIB_F_ALL),
 };
 EXPORT_SYMBOL(nft_fib_policy);
 
-#define NFTA_FIB_F_ALL (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR | \
-                       NFTA_FIB_F_MARK | NFTA_FIB_F_IIF | NFTA_FIB_F_OIF | \
-                       NFTA_FIB_F_PRESENT)
-
 int nft_fib_validate(const struct nft_ctx *ctx, const struct nft_expr *expr,
                     const struct nft_data **data)
 {
@@ -77,7 +78,7 @@ int nft_fib_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
 
        priv->flags = ntohl(nla_get_be32(tb[NFTA_FIB_FLAGS]));
 
-       if (priv->flags == 0 || (priv->flags & ~NFTA_FIB_F_ALL))
+       if (priv->flags == 0)
                return -EINVAL;
 
        if ((priv->flags & (NFTA_FIB_F_SADDR | NFTA_FIB_F_DADDR)) ==

diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c
index 29ac48c..870e5b1 100644 (file)
--- a/net/netfilter/nft_lookup.c
+++ b/net/netfilter/nft_lookup.c
@@ -90,7 +90,8 @@ static const struct nla_policy nft_lookup_policy[NFTA_LOOKUP_MAX + 1] = {
        [NFTA_LOOKUP_SET_ID]    = { .type = NLA_U32 },
        [NFTA_LOOKUP_SREG]      = { .type = NLA_U32 },
        [NFTA_LOOKUP_DREG]      = { .type = NLA_U32 },
-       [NFTA_LOOKUP_FLAGS]     = { .type = NLA_U32 },
+       [NFTA_LOOKUP_FLAGS]     =
+               NLA_POLICY_MASK(NLA_BE32, NFT_LOOKUP_F_INV),
 };
 
 static int nft_lookup_init(const struct nft_ctx *ctx,
@@ -120,9 +121,6 @@ static int nft_lookup_init(const struct nft_ctx *ctx,
        if (tb[NFTA_LOOKUP_FLAGS]) {
                flags = ntohl(nla_get_be32(tb[NFTA_LOOKUP_FLAGS]));
 
-               if (flags & ~NFT_LOOKUP_F_INV)
-                       return -EINVAL;
-
                if (flags & NFT_LOOKUP_F_INV)
                        priv->invert = true;
        }

diff --git a/net/netfilter/nft_masq.c b/net/netfilter/nft_masq.c
index b115d77..8a14aac 100644 (file)
--- a/net/netfilter/nft_masq.c
+++ b/net/netfilter/nft_masq.c
@@ -20,7 +20,8 @@ struct nft_masq {
 };
 
 static const struct nla_policy nft_masq_policy[NFTA_MASQ_MAX + 1] = {
-       [NFTA_MASQ_FLAGS]               = { .type = NLA_U32 },
+       [NFTA_MASQ_FLAGS]               =
+               NLA_POLICY_MASK(NLA_BE32, NF_NAT_RANGE_MASK),
        [NFTA_MASQ_REG_PROTO_MIN]       = { .type = NLA_U32 },
        [NFTA_MASQ_REG_PROTO_MAX]       = { .type = NLA_U32 },
 };
@@ -47,11 +48,8 @@ static int nft_masq_init(const struct nft_ctx *ctx,
        struct nft_masq *priv = nft_expr_priv(expr);
        int err;
 
-       if (tb[NFTA_MASQ_FLAGS]) {
+       if (tb[NFTA_MASQ_FLAGS])
                priv->flags = ntohl(nla_get_be32(tb[NFTA_MASQ_FLAGS]));
-               if (priv->flags & ~NF_NAT_RANGE_MASK)
-                       return -EINVAL;
-       }
 
        if (tb[NFTA_MASQ_REG_PROTO_MIN]) {
                err = nft_parse_register_load(tb[NFTA_MASQ_REG_PROTO_MIN],

diff --git a/net/netfilter/nft_nat.c b/net/netfilter/nft_nat.c
index 5c29915..583885c 100644 (file)
--- a/net/netfilter/nft_nat.c
+++ b/net/netfilter/nft_nat.c
@@ -132,7 +132,8 @@ static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = {
        [NFTA_NAT_REG_ADDR_MAX]  = { .type = NLA_U32 },
        [NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 },
        [NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 },
-       [NFTA_NAT_FLAGS]         = { .type = NLA_U32 },
+       [NFTA_NAT_FLAGS]         =
+               NLA_POLICY_MASK(NLA_BE32, NF_NAT_RANGE_MASK),
 };
 
 static int nft_nat_validate(const struct nft_ctx *ctx,
@@ -246,11 +247,8 @@ static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
                priv->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
        }
 
-       if (tb[NFTA_NAT_FLAGS]) {
+       if (tb[NFTA_NAT_FLAGS])
                priv->flags |= ntohl(nla_get_be32(tb[NFTA_NAT_FLAGS]));
-               if (priv->flags & ~NF_NAT_RANGE_MASK)
-                       return -EOPNOTSUPP;
-       }
 
        return nf_ct_netns_get(ctx->net, family);
 }

diff --git a/net/netfilter/nft_redir.c b/net/netfilter/nft_redir.c
index a70196f..a58bd8d 100644 (file)
--- a/net/netfilter/nft_redir.c
+++ b/net/netfilter/nft_redir.c
@@ -22,7 +22,8 @@ struct nft_redir {
 static const struct nla_policy nft_redir_policy[NFTA_REDIR_MAX + 1] = {
        [NFTA_REDIR_REG_PROTO_MIN]      = { .type = NLA_U32 },
        [NFTA_REDIR_REG_PROTO_MAX]      = { .type = NLA_U32 },
-       [NFTA_REDIR_FLAGS]              = { .type = NLA_U32 },
+       [NFTA_REDIR_FLAGS]              =
+               NLA_POLICY_MASK(NLA_BE32, NF_NAT_RANGE_MASK),
 };
 
 static int nft_redir_validate(const struct nft_ctx *ctx,
@@ -68,11 +69,8 @@ static int nft_redir_init(const struct nft_ctx *ctx,
                priv->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
        }
 
-       if (tb[NFTA_REDIR_FLAGS]) {
+       if (tb[NFTA_REDIR_FLAGS])
                priv->flags = ntohl(nla_get_be32(tb[NFTA_REDIR_FLAGS]));
-               if (priv->flags & ~NF_NAT_RANGE_MASK)
-                       return -EINVAL;
-       }
 
        return nf_ct_netns_get(ctx->net, ctx->family);
 }