diff options
| author |   Florian Westphal <fw@strlen.de> | 2017-04-16 01:29:19 +0200 |
|---|---|---|
| committer |   Pablo Neira Ayuso <pablo@netfilter.org> | 2017-04-19 17:55:17 +0200 |
| commit | b3a5db109e0670d6d168e9cd9de4d272a68f7c35 (patch) | |
| tree | ae23e5a9d0b2fd061130076bedc9560852cb11ef /net/netfilter | |
| parent | netfilter: remove last traces of variable-sized extensions (diff) | |
| download | linux-dev-b3a5db109e0670d6d168e9cd9de4d272a68f7c35.tar.xz linux-dev-b3a5db109e0670d6d168e9cd9de4d272a68f7c35.zip | |
netfilter: conntrack: use u8 for extension sizes again
commit 223b02d923ecd7c84cf9780bb3686f455d279279
("netfilter: nf_conntrack: reserve two bytes for nf_ct_ext->len")
had to increase size of the extension offsets because total size of the
extensions had increased to a point where u8 did overflow.
3 years later we've managed to diet extensions a bit and we no longer
need u16. Furthermore we can now add a compile-time assertion for this
problem.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter')
| -rw-r--r-- | net/netfilter/nf_conntrack_core.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 03150f60714d..62368b05cef5 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -1804,12 +1804,45 @@ EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize); module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint, &nf_conntrack_htable_size, 0600); +static unsigned int total_extension_size(void) +{ + /* remember to add new extensions below */ + BUILD_BUG_ON(NF_CT_EXT_NUM > 9); + + return sizeof(struct nf_ct_ext) + + sizeof(struct nf_conn_help) +#if IS_ENABLED(CONFIG_NF_NAT) + + sizeof(struct nf_conn_nat) +#endif + + sizeof(struct nf_conn_seqadj) + + sizeof(struct nf_conn_acct) +#ifdef CONFIG_NF_CONNTRACK_EVENTS + + sizeof(struct nf_conntrack_ecache) +#endif +#ifdef CONFIG_NF_CONNTRACK_TIMESTAMP + + sizeof(struct nf_conn_tstamp) +#endif +#ifdef CONFIG_NF_CONNTRACK_TIMEOUT + + sizeof(struct nf_conn_timeout) +#endif +#ifdef CONFIG_NF_CONNTRACK_LABELS + + sizeof(struct nf_conn_labels) +#endif +#if IS_ENABLED(CONFIG_NETFILTER_SYNPROXY) + + sizeof(struct nf_conn_synproxy) +#endif + ; +}; + int nf_conntrack_init_start(void) { int max_factor = 8; int ret = -ENOMEM; int i; + /* struct nf_ct_ext uses u8 to store offsets/size */ + BUILD_BUG_ON(total_extension_size() > 255u); + seqcount_init(&nf_conntrack_generation); for (i = 0; i < CONNTRACK_LOCKS; i++) |