From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Jamal Hadi Salim <jhs@mojatatu.com>,
        Jiri Pirko <jiri@resnulli.us>,
        Cong Wang <xiyou.wangcong@gmail.com>,
        "David S. Miller" <davem@davemloft.net>
Subject: [PATCH 4.20 142/183] net_sched: fix two more memory leaks in cls_tcindex
Date:   Mon, 25 Feb 2019 22:11:55 +0100
Message-Id: <20190225195118.818453238@linuxfoundation.org>
In-Reply-To: <20190225195054.748060397@linuxfoundation.org>
References: <20190225195054.748060397@linuxfoundation.org>
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4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Cong Wang <xiyou.wangcong@gmail.com>

[ Upstream commit 1db817e75f5b9387b8db11e37d5f0624eb9223e0 ]

struct tcindex_filter_result contains two parts:
struct tcf_exts and struct tcf_result.

For the local variable 'cr', its exts part is never used but
initialized without being released properly on success path. So
just completely remove the exts part to fix this leak.

For the local variable 'new_filter_result', it is never properly
released if not used by 'r' on success path.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 net/sched/cls_tcindex.c |   16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -304,9 +304,9 @@ tcindex_set_parms(struct net *net, struc
 		  struct nlattr *est, bool ovr, struct netlink_ext_ack *extack)
 {
 	struct tcindex_filter_result new_filter_result, *old_r = r;
-	struct tcindex_filter_result cr;
 	struct tcindex_data *cp = NULL, *oldp;
 	struct tcindex_filter *f = NULL; /* make gcc behave */
+	struct tcf_result cr = {};
 	int err, balloc = 0;
 	struct tcf_exts e;
 
@@ -347,11 +347,8 @@ tcindex_set_parms(struct net *net, struc
 	err = tcindex_filter_result_init(&new_filter_result);
 	if (err < 0)
 		goto errout1;
-	err = tcindex_filter_result_init(&cr);
-	if (err < 0)
-		goto errout1;
 	if (old_r)
-		cr.res = r->res;
+		cr = r->res;
 
 	if (tb[TCA_TCINDEX_HASH])
 		cp->hash = nla_get_u32(tb[TCA_TCINDEX_HASH]);
@@ -442,8 +439,8 @@ tcindex_set_parms(struct net *net, struc
 	}
 
 	if (tb[TCA_TCINDEX_CLASSID]) {
-		cr.res.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
-		tcf_bind_filter(tp, &cr.res, base);
+		cr.classid = nla_get_u32(tb[TCA_TCINDEX_CLASSID]);
+		tcf_bind_filter(tp, &cr, base);
 	}
 
 	if (old_r && old_r != r) {
@@ -455,7 +452,7 @@ tcindex_set_parms(struct net *net, struc
 	}
 
 	oldp = p;
-	r->res = cr.res;
+	r->res = cr;
 	tcf_exts_change(&r->exts, &e);
 
 	rcu_assign_pointer(tp->root, cp);
@@ -474,6 +471,8 @@ tcindex_set_parms(struct net *net, struc
 				; /* nothing */
 
 		rcu_assign_pointer(*fp, f);
+	} else {
+		tcf_exts_destroy(&new_filter_result.exts);
 	}
 
 	if (oldp)
@@ -486,7 +485,6 @@ errout_alloc:
 	else if (balloc == 2)
 		kfree(cp->h);
 errout1:
-	tcf_exts_destroy(&cr.exts);
 	tcf_exts_destroy(&new_filter_result.exts);
 errout:
 	kfree(cp);