| Message ID | 20120514143635.GA12992@1984 |
|---|---|
| State | Not Applicable |
| Headers | show |
On Mon, 2012-05-14 at 16:36 +0200, Pablo Neira Ayuso wrote: > On Mon, May 14, 2012 at 03:19:49PM +0100, David Laight wrote: > > > > > --- 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/1000) > > > + timeout = UINT_MAX/1000; > > > + > > > > Doesn't that rather assume that HZ is 1000 ? > > Indeed. I overlooked that. Thanks David. I dont think so. 1000 here is really MSEC_PER_SEC (All occurrences should be changed in this file) -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, 14 May 2012, Eric Dumazet wrote: > On Mon, 2012-05-14 at 16:36 +0200, Pablo Neira Ayuso wrote: > > On Mon, May 14, 2012 at 03:19:49PM +0100, David Laight wrote: > > > > > > > --- 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/1000) > > > > + timeout = UINT_MAX/1000; > > > > + > > > > > > Doesn't that rather assume that HZ is 1000 ? > > > > Indeed. I overlooked that. Thanks David. > > I dont think so. > > 1000 here is really MSEC_PER_SEC > > (All occurrences should be changed in this file) Yes, exactly. Pablo, shall I produce a little patch or could you change 1000 to MSEC_PER_SEC? Best regards, Jozsef - E-mail : kadlec@blackhole.kfki.hu, kadlecsik.jozsef@wigner.mta.hu PGP key : http://www.kfki.hu/~kadlec/pgp_public_key.txt Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences H-1525 Budapest 114, POB. 49, Hungary -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, May 14, 2012 at 07:45:07PM +0200, Jozsef Kadlecsik wrote: > On Mon, 14 May 2012, Eric Dumazet wrote: > > > On Mon, 2012-05-14 at 16:36 +0200, Pablo Neira Ayuso wrote: > > > On Mon, May 14, 2012 at 03:19:49PM +0100, David Laight wrote: > > > > > > > > > --- 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/1000) > > > > > + timeout = UINT_MAX/1000; > > > > > + > > > > > > > > Doesn't that rather assume that HZ is 1000 ? > > > > > > Indeed. I overlooked that. Thanks David. > > > > I dont think so. > > > > 1000 here is really MSEC_PER_SEC > > > > (All occurrences should be changed in this file) > > Yes, exactly. Pablo, shall I produce a little patch or could you change > 1000 to MSEC_PER_SEC? I'll mangle this myself. No need to send a new patch. -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
> -----Original Message----- > From: Eric Dumazet [mailto:eric.dumazet@gmail.com] > Sent: 14 May 2012 15:47 > To: Pablo Neira Ayuso > Cc: David Laight; netfilter-devel@vger.kernel.org; > davem@davemloft.net; netdev@vger.kernel.org; Jozsef Kadlecsik > Subject: Re: [PATCH 1/4] netfilter: ipset: fix timeout value > overflow bug > > On Mon, 2012-05-14 at 16:36 +0200, Pablo Neira Ayuso wrote: > > On Mon, May 14, 2012 at 03:19:49PM +0100, David Laight wrote: > > > > > > > --- 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/1000) > > > > + timeout = UINT_MAX/1000; > > > > + > > > > > > Doesn't that rather assume that HZ is 1000 ? > > > > Indeed. I overlooked that. Thanks David. > > I dont think so. > > 1000 here is really MSEC_PER_SEC I was just reading the comment above - which seemed to imply the purpose of the code was to ensure the timeout wouldn't exceeded 2^32 jiffies. I tend to use variable names for timeouts/timestamps that include the units - can make it more obvious when a divisor is absent - and makes it more obvious what the literal constants are converying beween. After all, the number of milliseconds in a second isn't subject to change :-) David -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
From bcb0e955ae5ea5acb1b59fb59e4fcb1c8364994d Mon Sep 17 00:00:00 2001 From: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> 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 <kadlec@blackhole.kfki.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- 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