net_sched: properly handle failure case of tcf_exts_init()

After commit 22dc13c837c3 ("net_sched: convert tcf_exts from list to pointer array")
we do dynamic allocation in tcf_exts_init(), therefore we need
to handle the ENOMEM case properly.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 65 insertions, 25 deletions

diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index 944c8ff45055..d9500709831f 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -219,10 +219,10 @@ static const struct nla_policy tcindex_policy[TCA_TCINDEX_MAX + 1] = {
 	[TCA_TCINDEX_CLASSID]		= { .type = NLA_U32 },
 };
 
-static void tcindex_filter_result_init(struct tcindex_filter_result *r)
+static int tcindex_filter_result_init(struct tcindex_filter_result *r)
 {
 	memset(r, 0, sizeof(*r));
-	tcf_exts_init(&r->exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+	return tcf_exts_init(&r->exts, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 }
 
 static void __tcindex_partial_destroy(struct rcu_head *head)
@@ -233,23 +233,57 @@ static void __tcindex_partial_destroy(struct rcu_head *head)
 	kfree(p);
 }
 
+static void tcindex_free_perfect_hash(struct tcindex_data *cp)
+{
+	int i;
+
+	for (i = 0; i < cp->hash; i++)
+		tcf_exts_destroy(&cp->perfect[i].exts);
+	kfree(cp->perfect);
+}
+
+static int tcindex_alloc_perfect_hash(struct tcindex_data *cp)
+{
+	int i, err = 0;
+
+	cp->perfect = kcalloc(cp->hash, sizeof(struct tcindex_filter_result),
+			      GFP_KERNEL);
+	if (!cp->perfect)
+		return -ENOMEM;
+
+	for (i = 0; i < cp->hash; i++) {
+		err = tcf_exts_init(&cp->perfect[i].exts,
+				    TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+		if (err < 0)
+			goto errout;
+	}
+
+	return 0;
+
+errout:
+	tcindex_free_perfect_hash(cp);
+	return err;
+}
+
 static int
 tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 		  u32 handle, struct tcindex_data *p,
 		  struct tcindex_filter_result *r, struct nlattr **tb,
 		  struct nlattr *est, bool ovr)
 {
-	int err, balloc = 0;
 	struct tcindex_filter_result new_filter_result, *old_r = r;
 	struct tcindex_filter_result cr;
-	struct tcindex_data *cp, *oldp;
+	struct tcindex_data *cp = NULL, *oldp;
 	struct tcindex_filter *f = NULL; /* make gcc behave */
+	int err, balloc = 0;
 	struct tcf_exts e;
 
-	tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
-	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
+	err = tcf_exts_init(&e, TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
 	if (err < 0)
 		return err;
+	err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
+	if (err < 0)
+		goto errout;
 
 	err = -ENOMEM;
 	/* tcindex_data attributes must look atomic to classifier/lookup so
@@ -270,19 +304,20 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	if (p->perfect) {
 		int i;
 
-		cp->perfect = kmemdup(p->perfect,
-				      sizeof(*r) * cp->hash, GFP_KERNEL);
-		if (!cp->perfect)
+		if (tcindex_alloc_perfect_hash(cp) < 0)
 			goto errout;
 		for (i = 0; i < cp->hash; i++)
-			tcf_exts_init(&cp->perfect[i].exts,
-				      TCA_TCINDEX_ACT, TCA_TCINDEX_POLICE);
+			cp->perfect[i].res = p->perfect[i].res;
 		balloc = 1;
 	}
 	cp->h = p->h;
 
-	tcindex_filter_result_init(&new_filter_result);
-	tcindex_filter_result_init(&cr);
+	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;
 
@@ -338,15 +373,8 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	err = -ENOMEM;
 	if (!cp->perfect && !cp->h) {
 		if (valid_perfect_hash(cp)) {
-			int i;
-
-			cp->perfect = kcalloc(cp->hash, sizeof(*r), GFP_KERNEL);
-			if (!cp->perfect)
+			if (tcindex_alloc_perfect_hash(cp) < 0)
 				goto errout_alloc;
-			for (i = 0; i < cp->hash; i++)
-				tcf_exts_init(&cp->perfect[i].exts,
-					      TCA_TCINDEX_ACT,
-					      TCA_TCINDEX_POLICE);
 			balloc = 1;
 		} else {
 			struct tcindex_filter __rcu **hash;
@@ -373,8 +401,12 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 		if (!f)
 			goto errout_alloc;
 		f->key = handle;
-		tcindex_filter_result_init(&f->result);
 		f->next = NULL;
+		err = tcindex_filter_result_init(&f->result);
+		if (err < 0) {
+			kfree(f);
+			goto errout_alloc;
+		}
 	}
 
 	if (tb[TCA_TCINDEX_CLASSID]) {
@@ -387,8 +419,13 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 	else
 		tcf_exts_change(tp, &cr.exts, &e);
 
-	if (old_r && old_r != r)
-		tcindex_filter_result_init(old_r);
+	if (old_r && old_r != r) {
+		err = tcindex_filter_result_init(old_r);
+		if (err < 0) {
+			kfree(f);
+			goto errout_alloc;
+		}
+	}
 
 	oldp = p;
 	r->res = cr.res;
@@ -415,9 +452,12 @@ tcindex_set_parms(struct net *net, struct tcf_proto *tp, unsigned long base,
 
 errout_alloc:
 	if (balloc == 1)
-		kfree(cp->perfect);
+		tcindex_free_perfect_hash(cp);
 	else if (balloc == 2)
 		kfree(cp->h);
+errout1:
+	tcf_exts_destroy(&cr.exts);
+	tcf_exts_destroy(&new_filter_result.exts);
 errout:
 	kfree(cp);
 	tcf_exts_destroy(&e);