From: Thomas Graf <tgraf@suug.ch>
Date: Tue, 8 Nov 2005 17:39:17 +0000 (-0800)
Subject: [PKT_SCHED]: Correctly handle empty ematch trees
X-Git-Tag: v2.6.15-rc1~416
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b541ca2c5a3f3f399d6f2ec9da33c1be5a8d8c19;p=linux-2.6

[PKT_SCHED]: Correctly handle empty ematch trees

Fixes an invalid memory reference when the basic classifier
is used without any ematches but just actions.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sched/ematch.c b/net/sched/ematch.c
index ebfe2e7d21..64b047c655 100644
--- a/net/sched/ematch.c
+++ b/net/sched/ematch.c
@@ -298,6 +298,11 @@ int tcf_em_tree_validate(struct tcf_proto *tp, struct rtattr *rta,
 	struct tcf_ematch_tree_hdr *tree_hdr;
 	struct tcf_ematch *em;
 
+	if (!rta) {
+		memset(tree, 0, sizeof(*tree));
+		return 0;
+	}
+
 	if (rtattr_parse_nested(tb, TCA_EMATCH_TREE_MAX, rta) < 0)
 		goto errout;