netfilter: xt_limit: have r->cost != 0 case work

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>

diff --git a/net/netfilter/xt_limit.c b/net/netfilter/xt_limit.c
index 5c22ce8..a4c1e45 100644 (file)
--- 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);
        }