netfilter: nfnetlink_acct: fix nfnl_acct_get operation

The get operation was not sending the message that was built to
user-space. This patch also includes the appropriate handling for
the return value of netlink_unicast().

Moreover, fix error codes on error (for example, for non-existing
entry was uncorrect).

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nfnetlink_acct.c b/net/netfilter/nfnetlink_acct.c
index 362ab6ca3dc10d9a485bd2dcbea2c4b381f1e31c..11ba013e47f620d7f7278f1277f0b0d3bb6d82df 100644 (file)
--- a/net/netfilter/nfnetlink_acct.c
+++ b/net/netfilter/nfnetlink_acct.c
@@ -166,7 +166,7 @@ static int
 nfnl_acct_get(struct sock *nfnl, struct sk_buff *skb,
             const struct nlmsghdr *nlh, const struct nlattr * const tb[])
 {
-       int ret = 0;
+       int ret = -ENOENT;
        struct nf_acct *cur;
        char *acct_name;
 
@@ -186,17 +186,26 @@ nfnl_acct_get(struct sock *nfnl, struct sk_buff *skb,
                        continue;
 
                skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
-               if (skb2 == NULL)
+               if (skb2 == NULL) {
+                       ret = -ENOMEM;
                        break;
+               }
 
                ret = nfnl_acct_fill_info(skb2, NETLINK_CB(skb).pid,
                                         nlh->nlmsg_seq,
                                         NFNL_MSG_TYPE(nlh->nlmsg_type),
                                         NFNL_MSG_ACCT_NEW, cur);
-               if (ret <= 0)
+               if (ret <= 0) {
                        kfree_skb(skb2);
+                       break;
+               }
+               ret = netlink_unicast(nfnl, skb2, NETLINK_CB(skb).pid,
+                                       MSG_DONTWAIT);
+               if (ret > 0)
+                       ret = 0;
 
-               break;
+               /* this avoids a loop in nfnetlink. */
+               return ret == -EAGAIN ? -ENOBUFS : ret;
        }
        return ret;
 }