[NETFILTER]: ctnetlink: fix deadlock in table dumping

ip_conntrack_put must not be called while holding ip_conntrack_lock
since destroy_conntrack takes it again.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2006-08-17 18:12:38 -07:00 committed by David S. Miller
parent 6e8fcbf640
commit d205dc4079
2 changed files with 14 additions and 20 deletions

View File

@ -415,21 +415,18 @@ ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
cb->args[0], *id); cb->args[0], *id);
read_lock_bh(&ip_conntrack_lock); read_lock_bh(&ip_conntrack_lock);
last = (struct ip_conntrack *)cb->args[1];
for (; cb->args[0] < ip_conntrack_htable_size; cb->args[0]++) { for (; cb->args[0] < ip_conntrack_htable_size; cb->args[0]++) {
restart: restart:
last = (struct ip_conntrack *)cb->args[1];
list_for_each_prev(i, &ip_conntrack_hash[cb->args[0]]) { list_for_each_prev(i, &ip_conntrack_hash[cb->args[0]]) {
h = (struct ip_conntrack_tuple_hash *) i; h = (struct ip_conntrack_tuple_hash *) i;
if (DIRECTION(h) != IP_CT_DIR_ORIGINAL) if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
continue; continue;
ct = tuplehash_to_ctrack(h); ct = tuplehash_to_ctrack(h);
if (last != NULL) { if (cb->args[1]) {
if (ct == last) { if (ct != last)
ip_conntrack_put(last);
cb->args[1] = 0;
last = NULL;
} else
continue; continue;
cb->args[1] = 0;
} }
if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid, if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, cb->nlh->nlmsg_seq,
@ -440,17 +437,17 @@ restart:
goto out; goto out;
} }
} }
if (last != NULL) { if (cb->args[1]) {
ip_conntrack_put(last);
cb->args[1] = 0; cb->args[1] = 0;
goto restart; goto restart;
} }
} }
out: out:
read_unlock_bh(&ip_conntrack_lock); read_unlock_bh(&ip_conntrack_lock);
if (last)
ip_conntrack_put(last);
DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id); DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
return skb->len; return skb->len;
} }

View File

@ -429,9 +429,9 @@ ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
cb->args[0], *id); cb->args[0], *id);
read_lock_bh(&nf_conntrack_lock); read_lock_bh(&nf_conntrack_lock);
last = (struct nf_conn *)cb->args[1];
for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) { for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
restart: restart:
last = (struct nf_conn *)cb->args[1];
list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) { list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
h = (struct nf_conntrack_tuple_hash *) i; h = (struct nf_conntrack_tuple_hash *) i;
if (DIRECTION(h) != IP_CT_DIR_ORIGINAL) if (DIRECTION(h) != IP_CT_DIR_ORIGINAL)
@ -442,13 +442,10 @@ restart:
* then dump everything. */ * then dump everything. */
if (l3proto && L3PROTO(ct) != l3proto) if (l3proto && L3PROTO(ct) != l3proto)
continue; continue;
if (last != NULL) { if (cb->args[1]) {
if (ct == last) { if (ct != last)
nf_ct_put(last);
cb->args[1] = 0;
last = NULL;
} else
continue; continue;
cb->args[1] = 0;
} }
if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid, if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, cb->nlh->nlmsg_seq,
@ -459,17 +456,17 @@ restart:
goto out; goto out;
} }
} }
if (last != NULL) { if (cb->args[1]) {
nf_ct_put(last);
cb->args[1] = 0; cb->args[1] = 0;
goto restart; goto restart;
} }
} }
out: out:
read_unlock_bh(&nf_conntrack_lock); read_unlock_bh(&nf_conntrack_lock);
if (last)
nf_ct_put(last);
DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id); DEBUGP("leaving, last bucket=%lu id=%u\n", cb->args[0], *id);
return skb->len; return skb->len;
} }