Commit 474803d3 authored by Liping Zhang's avatar Liping Zhang Committed by Pablo Neira Ayuso

netfilter: cttimeout: unlink timeout obj again when hash resize happen

Imagine such situation, nf_conntrack_htable_size now is 4096, we are doing
ctnl_untimeout, and iterate on 3000# bucket.

Meanwhile, another user try to reduce hash size to 2048, then all nf_conn
are removed to the new hashtable. When this hash resize operation finished,
we still try to itreate ct begin from 3000# bucket, find nothing to do and
just return.

We may miss unlinking some timeout objects. And later we will end up with
invalid references to timeout object that are already gone.

So when we find that hash resize happened, try to unlink timeout objects
from the 0# bucket again.
Signed-off-by: default avatarLiping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent 64b87639
...@@ -303,16 +303,24 @@ static void ctnl_untimeout(struct net *net, struct ctnl_timeout *timeout) ...@@ -303,16 +303,24 @@ static void ctnl_untimeout(struct net *net, struct ctnl_timeout *timeout)
{ {
struct nf_conntrack_tuple_hash *h; struct nf_conntrack_tuple_hash *h;
const struct hlist_nulls_node *nn; const struct hlist_nulls_node *nn;
unsigned int last_hsize;
spinlock_t *lock;
int i; int i;
local_bh_disable(); local_bh_disable();
for (i = 0; i < nf_conntrack_htable_size; i++) { restart:
nf_conntrack_lock(&nf_conntrack_locks[i % CONNTRACK_LOCKS]); last_hsize = nf_conntrack_htable_size;
if (i < nf_conntrack_htable_size) { for (i = 0; i < last_hsize; i++) {
hlist_nulls_for_each_entry(h, nn, &nf_conntrack_hash[i], hnnode) lock = &nf_conntrack_locks[i % CONNTRACK_LOCKS];
untimeout(h, timeout); nf_conntrack_lock(lock);
if (last_hsize != nf_conntrack_htable_size) {
spin_unlock(lock);
goto restart;
} }
spin_unlock(&nf_conntrack_locks[i % CONNTRACK_LOCKS]);
hlist_nulls_for_each_entry(h, nn, &nf_conntrack_hash[i], hnnode)
untimeout(h, timeout);
spin_unlock(lock);
} }
local_bh_enable(); local_bh_enable();
} }
......
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