netfilter: xt_qtaguid: add missing tracking for no filp case

In cases where the skb would have an sk_socket but no file, that skb
would not be counted at all. Assigning to uid 0 now.

Adding extra counters to track skb counts.

Change-Id: If049b4b525e1fbd5afc9c72b4a174c0a435f2ca7
Signed-off-by: JP Abgrall <jpa@google.com>

2 files changed, 26 insertions, 5 deletions

diff --git a/net/netfilter/xt_qtaguid.c b/net/netfilter/xt_qtaguid.c
index 32d855b1b6d2..b6b95c395e87 100644
--- a/net/netfilter/xt_qtaguid.c
+++ b/net/netfilter/xt_qtaguid.c
@@ -1588,6 +1588,7 @@ static bool qtaguid_mt(const struct sk_buff *skb, struct xt_action_param *par)
 	MT_DEBUG("qtaguid[%d]: entered skb=%p par->in=%p/out=%p fam=%d\n",
 		 par->hooknum, skb, par->in, par->out, par->family);
 
+	atomic64_inc(&qtu_events.match_calls);
 	if (skb == NULL) {
 		res = (info->match ^ info->invert) == 0;
 		goto ret_res;
@@ -1608,6 +1609,8 @@ static bool qtaguid_mt(const struct sk_buff *skb, struct xt_action_param *par)
 		got_sock = sk;
 		if (sk)
 			atomic64_inc(&qtu_events.match_found_sk_in_ct);
+		else
+			atomic64_inc(&qtu_events.match_found_no_sk_in_ct);
 	} else {
 		atomic64_inc(&qtu_events.match_found_sk);
 	}
@@ -1639,7 +1642,7 @@ static bool qtaguid_mt(const struct sk_buff *skb, struct xt_action_param *par)
 			par->hooknum,
 			sk ? sk->sk_socket : NULL);
 		res = (info->match ^ info->invert) == 0;
-		atomic64_inc(&qtu_events.match_found_sk_none);
+		atomic64_inc(&qtu_events.match_no_sk);
 		goto put_sock_ret_res;
 	} else if (info->match & info->invert & XT_QTAGUID_SOCKET) {
 		res = false;
@@ -1648,8 +1651,10 @@ static bool qtaguid_mt(const struct sk_buff *skb, struct xt_action_param *par)
 	filp = sk->sk_socket->file;
 	if (filp == NULL) {
 		MT_DEBUG("qtaguid[%d]: leaving filp=NULL\n", par->hooknum);
+		account_for_uid(skb, sk, 0, par);
 		res = ((info->match ^ info->invert) &
 			(XT_QTAGUID_UID | XT_QTAGUID_GID)) == 0;
+		atomic64_inc(&qtu_events.match_no_sk_file);
 		goto put_sock_ret_res;
 	}
 	sock_uid = filp->f_cred->fsuid;
@@ -1809,17 +1814,24 @@ static int qtaguid_ctrl_proc_read(char *page, char **num_items_returned,
 			       "counter_set_changes=%llu "
 			       "delete_cmds=%llu "
 			       "iface_events=%llu "
+			       "match_calls=%llu "
 			       "match_found_sk=%llu "
 			       "match_found_sk_in_ct=%llu "
-			       "match_found_sk_none=%llu\n",
+			       "match_found_no_sk_in_ct=%llu "
+			       "match_no_sk=%llu "
+			       "match_no_sk_file=%llu\n",
 			       atomic64_read(&qtu_events.sockets_tagged),
 			       atomic64_read(&qtu_events.sockets_untagged),
 			       atomic64_read(&qtu_events.counter_set_changes),
 			       atomic64_read(&qtu_events.delete_cmds),
 			       atomic64_read(&qtu_events.iface_events),
+			       atomic64_read(&qtu_events.match_calls),
 			       atomic64_read(&qtu_events.match_found_sk),
 			       atomic64_read(&qtu_events.match_found_sk_in_ct),
-			       atomic64_read(&qtu_events.match_found_sk_none));
+			       atomic64_read(
+				       &qtu_events.match_found_no_sk_in_ct),
+			       atomic64_read(&qtu_events.match_no_sk),
+			       atomic64_read(&qtu_events.match_no_sk_file));
 		if (len >= char_count) {
 			*outp = '\0';
 			return outp - page;
diff --git a/net/netfilter/xt_qtaguid_internal.h b/net/netfilter/xt_qtaguid_internal.h
index fdce0d006d30..02479d6d317d 100644
--- a/net/netfilter/xt_qtaguid_internal.h
+++ b/net/netfilter/xt_qtaguid_internal.h
@@ -252,18 +252,27 @@ struct qtaguid_event_counts {
 	atomic64_t counter_set_changes;
 	atomic64_t delete_cmds;
 	atomic64_t iface_events;  /* Number of NETDEV_* events handled */
+
+	atomic64_t match_calls;   /* Number of times iptables called mt */
 	/*
 	 * match_found_sk_*: numbers related to the netfilter matching
 	 * function finding a sock for the sk_buff.
+	 * Total skbs processed is sum(match_found*).
 	 */
 	atomic64_t match_found_sk;   /* An sk was already in the sk_buff. */
-	/* The connection tracker had the sk. */
+	/* The connection tracker had or didn't have the sk. */
 	atomic64_t match_found_sk_in_ct;
+	atomic64_t match_found_no_sk_in_ct;
 	/*
 	 * No sk could be found. No apparent owner. Could happen with
 	 * unsolicited traffic.
 	 */
-	atomic64_t match_found_sk_none;
+	atomic64_t match_no_sk;
+	/*
+	 * The file ptr in the sk_socket wasn't there.
+	 * This might happen for traffic while the socket is being closed.
+	 */
+	atomic64_t match_no_sk_file;
 };
 
 /* Track the set active_set for the given tag. */