From: JP Abgrall <jpa@google.com>
Date: Sun, 11 Sep 2011 19:13:41 +0000 (-0700)
Subject: netfilter: xt_qtaguid: warn only once for missing proc qtaguid data
X-Git-Tag: firefly_0821_release~7613^2~318
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ffebb241e1feefa944283399fe361be78b43bdfe;p=firefly-linux-kernel-4.4.55.git

netfilter: xt_qtaguid: warn only once for missing proc qtaguid data

When a process doesn't have /dev/xt_qtaguid open, only warn once
instead of for every ctrl access.

Change-Id: I98a462a8731254ddc3bf6d2fefeef9823659b1f0
Signed-off-by: JP Abgrall <jpa@google.com>
---

diff --git a/net/netfilter/xt_qtaguid.c b/net/netfilter/xt_qtaguid.c
index dff2ff3fd7cc..66eab3a9c4a4 100644
--- a/net/netfilter/xt_qtaguid.c
+++ b/net/netfilter/xt_qtaguid.c
@@ -1947,8 +1947,15 @@ static int ctrl_cmd_tag(const char *input)
 		spin_lock_bh(&uid_tag_data_tree_lock);
 		pqd_entry = proc_qtu_data_tree_search(
 			&proc_qtu_data_tree, current->tgid);
-		/* TODO: remove if() test, do BUG_ON() */
-		WARN_ON(IS_ERR_OR_NULL(pqd_entry));
+		/*
+		 * TODO: remove if, and start failing.
+		 * At first, we want to catch user-space code that is not
+		 * opening the /dev/xt_qtaguid.
+		 */
+		WARN_ONCE(IS_ERR_OR_NULL(pqd_entry),
+			  "qtaguid: User space forgot to open /dev/xt_qtaguid? "
+			  "pid=%u tgid=%u uid=%u\n",
+			  current->pid, current->tgid, current_fsuid());
 		if (!IS_ERR_OR_NULL(pqd_entry)) {
 			list_add(&sock_tag_entry->list,
 				 &pqd_entry->sock_tag_list);
@@ -2027,8 +2034,15 @@ static int ctrl_cmd_untag(const char *input)
 	spin_lock_bh(&uid_tag_data_tree_lock);
 	pqd_entry = proc_qtu_data_tree_search(
 		&proc_qtu_data_tree, current->tgid);
-	/* TODO: remove if() test, do BUG_ON() */
-	WARN_ON(IS_ERR_OR_NULL(pqd_entry));
+	/*
+	 * TODO: remove if, and start failing.
+	 * At first, we want to catch user-space code that is not
+	 * opening the /dev/xt_qtaguid.
+	 */
+	WARN_ONCE(IS_ERR_OR_NULL(pqd_entry),
+		  "qtaguid: User space forgot to open /dev/xt_qtaguid? "
+		  "pid=%u tgid=%u uid=%u\n",
+		  current->pid, current->tgid, current_fsuid());
 	if (!IS_ERR_OR_NULL(pqd_entry))
 		list_del(&sock_tag_entry->list);
 	spin_unlock_bh(&uid_tag_data_tree_lock);