lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 24 Jul 2014 16:50:37 +0200
From:	Nikolay Aleksandrov <nikolay@...hat.com>
To:	netdev@...r.kernel.org
Cc:	Florian Westphal <fw@...len.de>,
	Nikolay Aleksandrov <nikolay@...hat.com>,
	"David S. Miller" <davem@...emloft.net>,
	Alexey Kuznetsov <kuznet@....inr.ac.ru>,
	James Morris <jmorris@...ei.org>,
	Hideaki YOSHIFUJI <yoshfuji@...ux-ipv6.org>,
	Patrick McHardy <kaber@...sh.net>,
	Alexander Aring <alex.aring@...il.com>,
	Eric Dumazet <eric.dumazet@...il.com>
Subject: [PATCH net-next 9/9] inet: frag: set limits and make init_net's high_thresh limit global

This patch makes init_net's high_thresh limit to be the maximum for all
namespaces, thus introducing a global memory limit threshold equal to the
sum of the individual high_thresh limits which are capped.
It also introduces some sane minimums for low_thresh as it shouldn't be
able to drop below 0 (or > high_thresh in the unsigned case), and
overall low_thresh should not ever be above high_thresh, so we make the
following relations for a namespace:
init_net:
 high_thresh - max(not capped), min(init_net low_thresh)
 low_thresh - max(init_net high_thresh), min (0)

all other namespaces:
 high_thresh = max(init_net high_thresh), min(namespace's low_thresh)
 low_thresh = max(namespace's high_thresh), min(0)

The major issue with having low_thresh > high_thresh is that we'll
schedule eviction but never evict anything and thus rely only on the
timers.

Signed-off-by: Nikolay Aleksandrov <nikolay@...hat.com>
---
 Documentation/networking/ip-sysctl.txt  |  3 ++-
 net/ieee802154/reassembly.c             | 12 ++++++++++--
 net/ipv4/ip_fragment.c                  | 10 ++++++++--
 net/ipv6/netfilter/nf_conntrack_reasm.c | 12 ++++++++++--
 net/ipv6/reassembly.c                   | 12 ++++++++++--
 5 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index e8c304e37831..29a93518bf18 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -101,7 +101,8 @@ ipfrag_high_thresh - INTEGER
 	Maximum memory used to reassemble IP fragments. When
 	ipfrag_high_thresh bytes of memory is allocated for this purpose,
 	the fragment handler will toss packets until ipfrag_low_thresh
-	is reached.
+	is reached. This also serves as a maximum limit to namespaces
+	different from the initial one.
 
 ipfrag_low_thresh - INTEGER
 	Maximum memory used to reassemble IP fragments before the kernel
diff --git a/net/ieee802154/reassembly.c b/net/ieee802154/reassembly.c
index 8da635d92a58..f13d4f32e207 100644
--- a/net/ieee802154/reassembly.c
+++ b/net/ieee802154/reassembly.c
@@ -386,20 +386,25 @@ err:
 EXPORT_SYMBOL(lowpan_frag_rcv);
 
 #ifdef CONFIG_SYSCTL
+static int zero;
+
 static struct ctl_table lowpan_frags_ns_ctl_table[] = {
 	{
 		.procname	= "6lowpanfrag_high_thresh",
 		.data		= &init_net.ieee802154_lowpan.frags.high_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &init_net.ieee802154_lowpan.frags.low_thresh
 	},
 	{
 		.procname	= "6lowpanfrag_low_thresh",
 		.data		= &init_net.ieee802154_lowpan.frags.low_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &init_net.ieee802154_lowpan.frags.high_thresh
 	},
 	{
 		.procname	= "6lowpanfrag_time",
@@ -446,7 +451,10 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net)
 			goto err_alloc;
 
 		table[0].data = &ieee802154_lowpan->frags.high_thresh;
+		table[0].extra1 = &ieee802154_lowpan->frags.low_thresh;
+		table[0].extra2 = &init_net.ieee802154_lowpan.frags.high_thresh;
 		table[1].data = &ieee802154_lowpan->frags.low_thresh;
+		table[1].extra2 = &ieee802154_lowpan->frags.high_thresh;
 		table[2].data = &ieee802154_lowpan->frags.timeout;
 		table[3].data = &ieee802154_lowpan->max_dsize;
 
diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index ccee68dffd6e..634fc31aa243 100644
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -700,14 +700,17 @@ static struct ctl_table ip4_frags_ns_ctl_table[] = {
 		.data		= &init_net.ipv4.frags.high_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &init_net.ipv4.frags.low_thresh
 	},
 	{
 		.procname	= "ipfrag_low_thresh",
 		.data		= &init_net.ipv4.frags.low_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &init_net.ipv4.frags.high_thresh
 	},
 	{
 		.procname	= "ipfrag_time",
@@ -752,7 +755,10 @@ static int __net_init ip4_frags_ns_ctl_register(struct net *net)
 			goto err_alloc;
 
 		table[0].data = &net->ipv4.frags.high_thresh;
+		table[0].extra1 = &net->ipv4.frags.low_thresh;
+		table[0].extra2 = &init_net.ipv4.frags.high_thresh;
 		table[1].data = &net->ipv4.frags.low_thresh;
+		table[1].extra2 = &net->ipv4.frags.high_thresh;
 		table[2].data = &net->ipv4.frags.timeout;
 
 		/* Don't export sysctls to unprivileged users */
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 4d9da1e35f8c..3d4bccf6d67d 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -63,6 +63,8 @@ struct nf_ct_frag6_skb_cb
 static struct inet_frags nf_frags;
 
 #ifdef CONFIG_SYSCTL
+static int zero;
+
 static struct ctl_table nf_ct_frag6_sysctl_table[] = {
 	{
 		.procname	= "nf_conntrack_frag6_timeout",
@@ -76,14 +78,17 @@ static struct ctl_table nf_ct_frag6_sysctl_table[] = {
 		.data		= &init_net.nf_frag.frags.low_thresh,
 		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &init_net.nf_frag.frags.high_thresh
 	},
 	{
 		.procname	= "nf_conntrack_frag6_high_thresh",
 		.data		= &init_net.nf_frag.frags.high_thresh,
 		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &init_net.nf_frag.frags.low_thresh
 	},
 	{ }
 };
@@ -102,7 +107,10 @@ static int nf_ct_frag6_sysctl_register(struct net *net)
 
 		table[0].data = &net->nf_frag.frags.timeout;
 		table[1].data = &net->nf_frag.frags.low_thresh;
+		table[1].extra2 = &net->nf_frag.frags.high_thresh;
 		table[2].data = &net->nf_frag.frags.high_thresh;
+		table[2].extra1 = &net->nf_frag.frags.low_thresh;
+		table[2].extra2 = &init_net.nf_frag.frags.high_thresh;
 	}
 
 	hdr = register_net_sysctl(net, "net/netfilter", table);
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 57a9707b2032..f1709c4a289a 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -578,20 +578,25 @@ static const struct inet6_protocol frag_protocol =
 };
 
 #ifdef CONFIG_SYSCTL
+static int zero;
+
 static struct ctl_table ip6_frags_ns_ctl_table[] = {
 	{
 		.procname	= "ip6frag_high_thresh",
 		.data		= &init_net.ipv6.frags.high_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &init_net.ipv6.frags.low_thresh
 	},
 	{
 		.procname	= "ip6frag_low_thresh",
 		.data		= &init_net.ipv6.frags.low_thresh,
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_dointvec
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &init_net.ipv6.frags.high_thresh
 	},
 	{
 		.procname	= "ip6frag_time",
@@ -628,7 +633,10 @@ static int __net_init ip6_frags_ns_sysctl_register(struct net *net)
 			goto err_alloc;
 
 		table[0].data = &net->ipv6.frags.high_thresh;
+		table[0].extra1 = &net->ipv6.frags.low_thresh;
+		table[0].extra2 = &init_net.ipv6.frags.high_thresh;
 		table[1].data = &net->ipv6.frags.low_thresh;
+		table[1].extra2 = &net->ipv6.frags.high_thresh;
 		table[2].data = &net->ipv6.frags.timeout;
 
 		/* Don't export sysctls to unprivileged users */
-- 
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ