netfilter: ipset: fix timeout value overflow bug
Jozsef Kadlecsik [Mon, 7 May 2012 02:35:44 +0000 (02:35 +0000)]
commit 127f559127f5175e4bec3dab725a34845d956591 upstream.

Large timeout parameters could result wrong timeout values due to
an overflow at msec to jiffies conversion (reported by Andreas Herz)

[ This patch was mangled by Pablo Neira Ayuso since David Laight and
  Eric Dumazet noticed that we were using hardcoded 1000 instead of
  MSEC_PER_SEC to calculate the timeout ]

Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

include/linux/netfilter/ipset/ip_set_timeout.h
net/netfilter/xt_set.c

index 4792320..41d9cfa 100644 (file)
@@ -30,6 +30,10 @@ ip_set_timeout_uget(struct nlattr *tb)
 {
        unsigned int timeout = ip_set_get_h32(tb);
 
+       /* Normalize to fit into jiffies */
+       if (timeout > UINT_MAX/MSEC_PER_SEC)
+               timeout = UINT_MAX/MSEC_PER_SEC;
+
        /* Userspace supplied TIMEOUT parameter: adjust crazy size */
        return timeout == IPSET_NO_TIMEOUT ? IPSET_NO_TIMEOUT - 1 : timeout;
 }
index 0ec8138..035960e 100644 (file)
@@ -44,6 +44,14 @@ const struct ip_set_adt_opt n = {    \
        .cmdflags = cfs,                \
        .timeout = t,                   \
 }
+#define ADT_MOPT(n, f, d, fs, cfs, t)  \
+struct ip_set_adt_opt n = {            \
+       .family = f,                    \
+       .dim = d,                       \
+       .flags = fs,                    \
+       .cmdflags = cfs,                \
+       .timeout = t,                   \
+}
 
 /* Revision 0 interface: backward compatible with netfilter/iptables */
 
@@ -296,11 +304,14 @@ static unsigned int
 set_target_v2(struct sk_buff *skb, const struct xt_action_param *par)
 {
        const struct xt_set_info_target_v2 *info = par->targinfo;
-       ADT_OPT(add_opt, par->family, info->add_set.dim,
-               info->add_set.flags, info->flags, info->timeout);
+       ADT_MOPT(add_opt, par->family, info->add_set.dim,
+                info->add_set.flags, info->flags, info->timeout);
        ADT_OPT(del_opt, par->family, info->del_set.dim,
                info->del_set.flags, 0, UINT_MAX);
 
+       /* Normalize to fit into jiffies */
+       if (add_opt.timeout > UINT_MAX/MSEC_PER_SEC)
+               add_opt.timeout = UINT_MAX/MSEC_PER_SEC;
        if (info->add_set.index != IPSET_INVALID_ID)
                ip_set_add(info->add_set.index, skb, par, &add_opt);
        if (info->del_set.index != IPSET_INVALID_ID)