netfilter: nf_tables: Fix for endless loop when dumping ruleset
__nf_tables_dump_rules() stores the current idx value into cb->args[0]
before returning to caller. With multiple chains present, cb->args[0] is
therefore updated after each chain's rules have been traversed. This
though causes the final nf_tables_dump_rules() run (which should return
an skb->len of zero since no rules are left to dump) to continue dumping
rules for each but the first chain. Fix this by moving the cb->args[0]
update to nf_tables_dump_rules().
With no final action to be performed anymore in
__nf_tables_dump_rules(), drop 'out_unfinished' jump label and 'rc'
variable - instead return the appropriate value directly.
Fixes: 241faeceb849c ("netfilter: nf_tables: Speed up selective rule dumps")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 2b0a933..e3ddd8e 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2304,7 +2304,6 @@
struct net *net = sock_net(skb->sk);
unsigned int s_idx = cb->args[0];
const struct nft_rule *rule;
- int rc = 1;
list_for_each_entry_rcu(rule, &chain->rules, list) {
if (!nft_is_active(net, rule))
@@ -2321,16 +2320,13 @@
NLM_F_MULTI | NLM_F_APPEND,
table->family,
table, chain, rule) < 0)
- goto out_unfinished;
+ return 1;
nl_dump_check_consistent(cb, nlmsg_hdr(skb));
cont:
(*idx)++;
}
- rc = 0;
-out_unfinished:
- cb->args[0] = *idx;
- return rc;
+ return 0;
}
static int nf_tables_dump_rules(struct sk_buff *skb,
@@ -2382,6 +2378,8 @@
}
done:
rcu_read_unlock();
+
+ cb->args[0] = idx;
return skb->len;
}
