net_sched: Fix stack info leak in cbq_dump_wrr().

[ Upstream commit a0db856a95a29efb1c23db55c02d9f0ff4f0db48 ]

Make sure the reserved fields, and padding (if any), are
fully initialized.

Based upon a patch by Dan Carpenter and feedback from
Joe Perches.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index 1bc210ffcba2a524750b3382d444a87db2c08c2c..8ec15988b5f39fcb590ae6e5e0c495282853c134 100644 (file)
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1465,6 +1465,7 @@ static int cbq_dump_wrr(struct sk_buff *skb, struct cbq_class *cl)
        unsigned char *b = skb_tail_pointer(skb);
        struct tc_cbq_wrropt opt;
 
+       memset(&opt, 0, sizeof(opt));
        opt.flags = 0;
        opt.allot = cl->allot;
        opt.priority = cl->priority + 1;