netfilter: ctnetlink: don't use conntrack/expect object addresses as id

else, we leak the addresses to userspace via ctnetlink events
and dumps.

Compute an ID on demand based on the immutable parts of nf_conn struct.

Another advantage compared to using an address is that there is no
immediate re-use of the same ID in case the conntrack entry is freed and
reallocated again immediately.

Fixes: 3583240249 ("[NETFILTER]: nf_conntrack_expect: kill unique ID")
Fixes: 7f85f91472 ("[NETFILTER]: nf_conntrack: kill unique ID")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal
2019-04-01 13:08:54 +02:00
committed by Pablo Neira Ayuso
parent 0261ea1bd1
commit 3c79107631
3 changed files with 66 additions and 5 deletions

View File

@@ -316,6 +316,8 @@ struct nf_conn *nf_ct_tmpl_alloc(struct net *net,
gfp_t flags);
void nf_ct_tmpl_free(struct nf_conn *tmpl);
u32 nf_ct_get_id(const struct nf_conn *ct);
static inline void
nf_ct_set(struct sk_buff *skb, struct nf_conn *ct, enum ip_conntrack_info info)
{