From bcb0e955ae5ea5acb1b59fb59e4fcb1c8364994d Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik Date: Mon, 7 May 2012 02:35:44 +0000 Subject: [PATCH] netfilter: ipset: fix timeout value overflow bug 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 notices that we were using hardcode 1000 instead of HZ to calculate the timeout ] Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso --- include/linux/netfilter/ipset/ip_set_timeout.h | 4 ++++ net/netfilter/xt_set.c | 15 +++++++++++++-- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/include/linux/netfilter/ipset/ip_set_timeout.h b/include/linux/netfilter/ipset/ip_set_timeout.h index 4792320..40a85b1 100644 --- a/include/linux/netfilter/ipset/ip_set_timeout.h +++ b/include/linux/netfilter/ipset/ip_set_timeout.h @@ -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/HZ) + timeout = UINT_MAX/HZ; + /* Userspace supplied TIMEOUT parameter: adjust crazy size */ return timeout == IPSET_NO_TIMEOUT ? IPSET_NO_TIMEOUT - 1 : timeout; } diff --git a/net/netfilter/xt_set.c b/net/netfilter/xt_set.c index 0ec8138..15275e9 100644 --- a/net/netfilter/xt_set.c +++ b/net/netfilter/xt_set.c @@ -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/HZ) + add_opt.timeout = UINT_MAX/HZ; 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) -- 1.7.10