[34-longterm 101/209] net sched: fix kernel leak in act_police

From: Paul Gortmaker
Date: Thu Apr 14 2011 - 13:52:04 EST


From: Jeff Mahoney <jeffm@xxxxxxxx>

=====================================================================
| This is a commit scheduled for the next v2.6.34 longterm release. |
| If you see a problem with using this for longterm, please comment.|
=====================================================================

commit 0f04cfd098fb81fded74e78ea1a1b86cc6c6c31e upstream.

While reviewing commit 1c40be12f7d8ca1d387510d39787b12e512a7ce8, I
audited other users of tc_action_ops->dump for information leaks.

That commit covered almost all of them but act_police still had a leak.

opt.limit and opt.capab aren't zeroed out before the structure is
passed out.

This patch uses the C99 initializers to zero everything unused out.

Signed-off-by: Jeff Mahoney <jeffm@xxxxxxxx>
Acked-by: Jeff Mahoney <jeffm@xxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
net/sched/act_police.c | 21 +++++++++------------
1 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 654f73d..bf93162 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -341,22 +341,19 @@ tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_police *police = a->priv;
- struct tc_police opt;
-
- opt.index = police->tcf_index;
- opt.action = police->tcf_action;
- opt.mtu = police->tcfp_mtu;
- opt.burst = police->tcfp_burst;
- opt.refcnt = police->tcf_refcnt - ref;
- opt.bindcnt = police->tcf_bindcnt - bind;
+ struct tc_police opt = {
+ .index = police->tcf_index,
+ .action = police->tcf_action,
+ .mtu = police->tcfp_mtu,
+ .burst = police->tcfp_burst,
+ .refcnt = police->tcf_refcnt - ref,
+ .bindcnt = police->tcf_bindcnt - bind,
+ };
+
if (police->tcfp_R_tab)
opt.rate = police->tcfp_R_tab->rate;
- else
- memset(&opt.rate, 0, sizeof(opt.rate));
if (police->tcfp_P_tab)
opt.peakrate = police->tcfp_P_tab->rate;
- else
- memset(&opt.peakrate, 0, sizeof(opt.peakrate));
NLA_PUT(skb, TCA_POLICE_TBF, sizeof(opt), &opt);
if (police->tcfp_result)
NLA_PUT_U32(skb, TCA_POLICE_RESULT, police->tcfp_result);
--
1.7.4.4

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