net sched: fix some kernel memory leaks

We leak at least 32bits of kernel memory to user land in tc dump,
because we dont init all fields (capab ?) of the dumped structure.

Use C99 initializers so that holes and non explicit fields are zeroed.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 9 deletions

diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index 8406c665..c2ed90a 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -152,21 +152,24 @@ static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result
 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
 	unsigned char *b = skb_tail_pointer(skb);
-	struct tc_gact opt;
 	struct tcf_gact *gact = a->priv;
+	struct tc_gact opt = {
+		.index   = gact->tcf_index,
+		.refcnt  = gact->tcf_refcnt - ref,
+		.bindcnt = gact->tcf_bindcnt - bind,
+		.action  = gact->tcf_action,
+	};
 	struct tcf_t t;
 
-	opt.index = gact->tcf_index;
-	opt.refcnt = gact->tcf_refcnt - ref;
-	opt.bindcnt = gact->tcf_bindcnt - bind;
-	opt.action = gact->tcf_action;
 	NLA_PUT(skb, TCA_GACT_PARMS, sizeof(opt), &opt);
 #ifdef CONFIG_GACT_PROB
 	if (gact->tcfg_ptype) {
-		struct tc_gact_p p_opt;
-		p_opt.paction = gact->tcfg_paction;
-		p_opt.pval = gact->tcfg_pval;
-		p_opt.ptype = gact->tcfg_ptype;
+		struct tc_gact_p p_opt = {
+			.paction = gact->tcfg_paction,
+			.pval    = gact->tcfg_pval,
+			.ptype   = gact->tcfg_ptype,
+		};
+
 		NLA_PUT(skb, TCA_GACT_PROB, sizeof(p_opt), &p_opt);
 	}
 #endif