1 files changed, 33 insertions, 3 deletions

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 9aef93300f1c..6b12883e04b8 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -160,11 +160,22 @@ static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 	return TC_H_MAJ(first);
 }
 
+static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
+{
+	if (kind)
+		return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ;
+	memset(name, 0, IFNAMSIZ);
+	return false;
+}
+
 static bool tcf_proto_is_unlocked(const char *kind)
 {
 	const struct tcf_proto_ops *ops;
 	bool ret;
 
+	if (strlen(kind) == 0)
+		return false;
+
 	ops = tcf_proto_lookup_ops(kind, false, NULL);
 	/* On error return false to take rtnl lock. Proto lookup/create
 	 * functions will perform lookup again and properly handle errors.
@@ -1976,6 +1987,7 @@ static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tca[TCA_MAX + 1];
+	char name[IFNAMSIZ];
 	struct tcmsg *t;
 	u32 protocol;
 	u32 prio;
@@ -2032,13 +2044,19 @@ replay:
 	if (err)
 		return err;
 
+	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
+		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
+		err = -EINVAL;
+		goto errout;
+	}
+
 	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
 	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
 	 * type is not specified, classifier is not unlocked.
 	 */
 	if (rtnl_held ||
 	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
-	    !tca[TCA_KIND] || !tcf_proto_is_unlocked(nla_data(tca[TCA_KIND]))) {
+	    !tcf_proto_is_unlocked(name)) {
 		rtnl_held = true;
 		rtnl_lock();
 	}
@@ -2196,6 +2214,7 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tca[TCA_MAX + 1];
+	char name[IFNAMSIZ];
 	struct tcmsg *t;
 	u32 protocol;
 	u32 prio;
@@ -2235,13 +2254,18 @@ static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 	if (err)
 		return err;
 
+	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
+		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
+		err = -EINVAL;
+		goto errout;
+	}
 	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
 	 * found), qdisc is not unlocked, classifier type is not specified,
 	 * classifier is not unlocked.
 	 */
 	if (!prio ||
 	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
-	    !tca[TCA_KIND] || !tcf_proto_is_unlocked(nla_data(tca[TCA_KIND]))) {
+	    !tcf_proto_is_unlocked(name)) {
 		rtnl_held = true;
 		rtnl_lock();
 	}
@@ -2349,6 +2373,7 @@ static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 {
 	struct net *net = sock_net(skb->sk);
 	struct nlattr *tca[TCA_MAX + 1];
+	char name[IFNAMSIZ];
 	struct tcmsg *t;
 	u32 protocol;
 	u32 prio;
@@ -2385,12 +2410,17 @@ static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
 	if (err)
 		return err;
 
+	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
+		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
+		err = -EINVAL;
+		goto errout;
+	}
 	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
 	 * unlocked, classifier type is not specified, classifier is not
 	 * unlocked.
 	 */
 	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
-	    !tca[TCA_KIND] || !tcf_proto_is_unlocked(nla_data(tca[TCA_KIND]))) {
+	    !tcf_proto_is_unlocked(name)) {
 		rtnl_held = true;
 		rtnl_lock();
 	}