diff options
author | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-01-14 15:33:57 +0100 |
---|---|---|
committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2015-01-19 14:52:39 +0100 |
commit | 75e8d06d4308436055d1a78a2c02bf6328ba724d (patch) | |
tree | 64fcef16df64c35c2f3ceca20982d3723a2637c4 /net/bridge | |
parent | 2061dcd6bff8b774b4fac8b0739b6be3f87bc9f2 (diff) |
netfilter: nf_tables: validate hooks in NAT expressions
The user can crash the kernel if it uses any of the existing NAT
expressions from the wrong hook, so add some code to validate this
when loading the rule.
This patch introduces nft_chain_validate_hooks() which is based on
an existing function in the bridge version of the reject expression.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/bridge')
-rw-r--r-- | net/bridge/netfilter/nft_reject_bridge.c | 29 |
1 files changed, 6 insertions, 23 deletions
diff --git a/net/bridge/netfilter/nft_reject_bridge.c b/net/bridge/netfilter/nft_reject_bridge.c index b0330aecbf97..3244aead0926 100644 --- a/net/bridge/netfilter/nft_reject_bridge.c +++ b/net/bridge/netfilter/nft_reject_bridge.c @@ -265,22 +265,12 @@ out: data[NFT_REG_VERDICT].verdict = NF_DROP; } -static int nft_reject_bridge_validate_hooks(const struct nft_chain *chain) +static int nft_reject_bridge_validate(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nft_data **data) { - struct nft_base_chain *basechain; - - if (chain->flags & NFT_BASE_CHAIN) { - basechain = nft_base_chain(chain); - - switch (basechain->ops[0].hooknum) { - case NF_BR_PRE_ROUTING: - case NF_BR_LOCAL_IN: - break; - default: - return -EOPNOTSUPP; - } - } - return 0; + return nft_chain_validate_hooks(ctx->chain, (1 << NF_BR_PRE_ROUTING) | + (1 << NF_BR_LOCAL_IN)); } static int nft_reject_bridge_init(const struct nft_ctx *ctx, @@ -290,7 +280,7 @@ static int nft_reject_bridge_init(const struct nft_ctx *ctx, struct nft_reject *priv = nft_expr_priv(expr); int icmp_code, err; - err = nft_reject_bridge_validate_hooks(ctx->chain); + err = nft_reject_bridge_validate(ctx, expr, NULL); if (err < 0) return err; @@ -341,13 +331,6 @@ nla_put_failure: return -1; } -static int nft_reject_bridge_validate(const struct nft_ctx *ctx, - const struct nft_expr *expr, - const struct nft_data **data) -{ - return nft_reject_bridge_validate_hooks(ctx->chain); -} - static struct nft_expr_type nft_reject_bridge_type; static const struct nft_expr_ops nft_reject_bridge_ops = { .type = &nft_reject_bridge_type, |