[ 142/147] netfilter: xt_limit: have r->cost != 0 case work

Ben Hutchings
2012-10-14T14:42:01Z

From: Jan Engelhardt <jengelh@inai.de>

commit 82e6bfe2fbc4d48852114c4f979137cd5bf1d1a8 upstream.

Commit v2.6.19-rc1~1272^2~41 tells us that r->cost != 0 can happen when
a running state is saved to userspace and then reinstated from there.

Make sure that private xt_limit area is initialized with correct values.
Otherwise, random matchings due to use of uninitialized memory.

Signed-off-by: Jan Engelhardt <jengelh@inai.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
net/netfilter/xt_limit.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/netfilter/xt_limit.c b/net/netfilter/xt_limit.c
index 5c22ce8..a4c1e45 100644
--- a/net/netfilter/xt_limit.c
+++ b/net/netfilter/xt_limit.c
@@ -117,11 +117,11 @@ static int limit_mt_check(const struct xt_mtchk_param *par)

/* For SMP, we only want to use one set of state. */
r->master = priv;
+ /* User avg in seconds * XT_LIMIT_SCALE: convert to jiffies *
+ 128. */
+ priv->prev = jiffies;
+ priv->credit = user2credits(r->avg * r->burst); /* Credits full. */
if (r->cost == 0) {
- /* User avg in seconds * XT_LIMIT_SCALE: convert to jiffies *
- 128. */
- priv->prev = jiffies;
- priv->credit = user2credits(r->avg * r->burst); /* Credits full. */
r->credit_cap = priv->credit; /* Credits full. */
r->cost = user2credits(r->avg);
}