Commit 18bbc321 authored by Florian Westphal's avatar Florian Westphal
Browse files

netfilter: nft_tproxy: restrict to prerouting hook 



TPROXY is only allowed from prerouting, but nft_tproxy doesn't check this.
This fixes a crash (null dereference) when using tproxy from e.g. output.

Fixes: 4ed8eb65 ("netfilter: nf_tables: Add native tproxy support")
Reported-by: default avatarShell Chen <xierch@gmail.com>
Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
parent cf97769c

net/netfilter/nft_tproxy.c

+8 −0
Original line number Diff line number Diff line
@@ -312,6 +312,13 @@ static int nft_tproxy_dump(struct sk_buff *skb, 
	return 0;

}



static int nft_tproxy_validate(const struct nft_ctx *ctx,

			       const struct nft_expr *expr,

			       const struct nft_data **data)

{

	return nft_chain_validate_hooks(ctx->chain, 1 << NF_INET_PRE_ROUTING);

}



static struct nft_expr_type nft_tproxy_type;

static const struct nft_expr_ops nft_tproxy_ops = {

	.type		= &nft_tproxy_type,
@@ -321,6 +328,7 @@ static const struct nft_expr_ops nft_tproxy_ops = { 
	.destroy	= nft_tproxy_destroy,

	.dump		= nft_tproxy_dump,

	.reduce		= NFT_REDUCE_READONLY,

	.validate	= nft_tproxy_validate,

};



static struct nft_expr_type nft_tproxy_type __read_mostly = {