From a0a7379e16b6e4c229d082f24c7e3ef9e812ed46 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Tue, 10 Jun 2014 10:53:01 +0200 Subject: [PATCH] netfilter: nf_tables: use u32 for chain use counter Since 4fefee5 ("netfilter: nf_tables: allow to delete several objects from a batch"), every new rule bumps the chain use counter. However, this is limited to 16 bits, which means that it will overrun after 2^16 rules. Use a u32 chain counter and check for overflows (just like we do for table objects). Signed-off-by: Pablo Neira Ayuso --- include/net/netfilter/nf_tables.h | 6 +++--- net/netfilter/nf_tables_api.c | 3 +++ 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h index 7ee6ce6564ae..713b0b88bd5a 100644 --- a/include/net/netfilter/nf_tables.h +++ b/include/net/netfilter/nf_tables.h @@ -503,9 +503,9 @@ enum nft_chain_flags { * @net: net namespace that this chain belongs to * @table: table that this chain belongs to * @handle: chain handle - * @flags: bitmask of enum nft_chain_flags * @use: number of jump references to this chain * @level: length of longest path to this chain + * @flags: bitmask of enum nft_chain_flags * @name: name of the chain */ struct nft_chain { @@ -514,9 +514,9 @@ struct nft_chain { struct net *net; struct nft_table *table; u64 handle; - u8 flags; - u16 use; + u32 use; u16 level; + u8 flags; char name[NFT_CHAIN_MAXNAMELEN]; }; diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index ba37c10e5139..5586426a6169 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -1730,6 +1730,9 @@ static int nf_tables_newrule(struct sock *nlsk, struct sk_buff *skb, if (!create || nlh->nlmsg_flags & NLM_F_REPLACE) return -EINVAL; handle = nf_tables_alloc_handle(table); + + if (chain->use == UINT_MAX) + return -EOVERFLOW; } if (nla[NFTA_RULE_POSITION]) {