[PATCH net-next] netfilter: nf_conntrack: remove the unneed check for *bucket

In the 'for(...) {}', the *bucket alwasy < net->ct.htable_size,
so remove the check

Signed-off-by: Weidong Wang <redacted>
---
 net/netfilter/nf_conntrack_core.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 3cb3cb8..cd7d5c8 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c

@@ -1383,14 +1383,12 @@ get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data),
 		lockp = &nf_conntrack_locks[*bucket % CONNTRACK_LOCKS];
 		local_bh_disable();
 		spin_lock(lockp);
-		if (*bucket < net->ct.htable_size) {
-			hlist_nulls_for_each_entry(h, n, &net->ct.hash[*bucket], hnnode) {
-				if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
-					continue;
-				ct = nf_ct_tuplehash_to_ctrack(h);
-				if (iter(ct, data))
-					goto found;
-			}
+		hlist_nulls_for_each_entry(h, n, &net->ct.hash[*bucket], hnnode) {
+			if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
+				continue;
+			ct = nf_ct_tuplehash_to_ctrack(h);
+			if (iter(ct, data))
+				goto found;
 		}
 		spin_unlock(lockp);
 		local_bh_enable();

-- 
2.7.0

Weidong Wang [off-list ref] wrote:

AFAIU net->ct.htable_size can shrink between for-test and aquiring
the bucket lockp, so this additional if-test is needed.

On 2016/1/31 5:30, Florian Westphal wrote:

Weidong Wang [off-list ref] wrote:

quoted

In the 'for(...) {}', the *bucket alwasy < net->ct.htable_size,
so remove the check

@@ -1383,14 +1383,12 @@ get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data),
 		lockp = &nf_conntrack_locks[*bucket % CONNTRACK_LOCKS];
 		local_bh_disable();
 		spin_lock(lockp);
-		if (*bucket < net->ct.htable_size) {

AFAIU net->ct.htable_size can shrink between for-test and aquiring
the bucket lockp, so this additional if-test is needed.

ok, Got it.
So ignore this patch.

Regards,
Weidong

.

From: Florian Westphal

Sent: 30 January 2016 21:30
Weidong Wang [off-list ref] wrote:

quoted

In the 'for(...) {}', the *bucket alwasy < net->ct.htable_size,
so remove the check

@@ -1383,14 +1383,12 @@ get_next_corpse(struct net *net, int (*iter)(struct nf_conn *i, void *data),
 		lockp = &nf_conntrack_locks[*bucket % CONNTRACK_LOCKS];
 		local_bh_disable();
 		spin_lock(lockp);
-		if (*bucket < net->ct.htable_size) {

AFAIU net->ct.htable_size can shrink between for-test and aquiring
the bucket lockp, so this additional if-test is needed.

If the table can shrink, can it not also grow - in which case
the references bucket will be incorrect?

	David