From: JP Abgrall <jpa@google.com>
Date: Tue, 12 Jul 2011 19:02:59 +0000 (-0700)
Subject: netfitler: fixup the quota2, and enable.
X-Git-Tag: firefly_0821_release~7613^2~442
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b4294d618e8a19bb47826e51ae52b9fb2fe05f80;p=firefly-linux-kernel-4.4.55.git
netfitler: fixup the quota2, and enable.
The xt_quota2 came from
http://sourceforge.net/projects/xtables-addons/develop
It needed tweaking for it to compile within the kernel tree.
Fixed kmalloc() and create_proc_entry() invocations within
a non-interruptible context.
Removed useless copying of current quota back to the iptable's
struct matchinfo:
- those are per CPU: they will change randomly based on which
cpu gets to update the value.
- they prevent matching a rule: e.g.
-A chain -m quota2 --name q1 --quota 123
can't be followed by
-D chain -m quota2 --name q1 --quota 123
as the 123 will be compared to the struct matchinfo's quota member.
Change-Id: I021d3b743db3b22158cc49acb5c94d905b501492
Signed-off-by: JP Abgrall <jpa@google.com>
---
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index a704486d4ba7..ddb7bb507bd5 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -963,6 +963,18 @@ config NETFILTER_XT_MATCH_QUOTA
If you want to compile it as a module, say M here and read
<file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
+config NETFILTER_XT_MATCH_QUOTA2
+ tristate '"quota2" match support'
+ depends on NETFILTER_ADVANCED
+ help
+ This option adds a `quota2' match, which allows to match on a
+ byte counter correctly and not per CPU.
+ It allows naming the quotas.
+ This is based on http://xtables-addons.git.sourceforge.net
+
+ If you want to compile it as a module, say M here and read
+ <file:Documentation/kbuild/modules.txt>. If unsure, say `N'.
+
config NETFILTER_XT_MATCH_RATEEST
tristate '"rateest" match support'
depends on NETFILTER_ADVANCED
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 5c7b91e0adcb..8b658ef78501 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -97,6 +97,7 @@ obj-$(CONFIG_NETFILTER_XT_MATCH_PKTTYPE) += xt_pkttype.o
obj-$(CONFIG_NETFILTER_XT_MATCH_POLICY) += xt_policy.o
obj-$(CONFIG_NETFILTER_XT_MATCH_QTAGUID) += xt_qtaguid.o
obj-$(CONFIG_NETFILTER_XT_MATCH_QUOTA) += xt_quota.o
+obj-$(CONFIG_NETFILTER_XT_MATCH_QUOTA2) += xt_quota2.o
obj-$(CONFIG_NETFILTER_XT_MATCH_RATEEST) += xt_rateest.o
obj-$(CONFIG_NETFILTER_XT_MATCH_REALM) += xt_realm.o
obj-$(CONFIG_NETFILTER_XT_MATCH_RECENT) += xt_recent.o
diff --git a/net/netfilter/xt_quota2.c b/net/netfilter/xt_quota2.c
index 4857008f1eb0..454ce10c8cdc 100644
--- a/net/netfilter/xt_quota2.c
+++ b/net/netfilter/xt_quota2.c
@@ -18,8 +18,7 @@
#include <asm/atomic.h>
#include <linux/netfilter/x_tables.h>
-#include "xt_quota2.h"
-#include "compat_xtables.h"
+#include <linux/netfilter/xt_quota2.h>
/**
* @lock: lock to protect quota writers from each other
@@ -91,7 +90,7 @@ q2_new_counter(const struct xt_quota_mtinfo2 *q, bool anon)
if (!anon) {
INIT_LIST_HEAD(&e->list);
atomic_set(&e->ref, 1);
- strncpy(e->name, q->name, sizeof(e->name));
+ strlcpy(e->name, q->name, sizeof(e->name));
}
return e;
}
@@ -104,42 +103,56 @@ static struct xt_quota_counter *
q2_get_counter(const struct xt_quota_mtinfo2 *q)
{
struct proc_dir_entry *p;
- struct xt_quota_counter *e;
+ struct xt_quota_counter *e = NULL;
+ struct xt_quota_counter *new_e;
if (*q->name == '\0')
return q2_new_counter(q, true);
+ /* No need to hold a lock while getting a new counter */
+ new_e = q2_new_counter(q, false);
+ if (new_e == NULL)
+ goto out;
+
spin_lock_bh(&counter_list_lock);
list_for_each_entry(e, &counter_list, list)
if (strcmp(e->name, q->name) == 0) {
atomic_inc(&e->ref);
spin_unlock_bh(&counter_list_lock);
+ kfree(new_e);
+ pr_debug("xt_quota2: old counter name=%s", e->name);
return e;
}
+ e = new_e;
+ pr_debug("xt_quota2: new_counter name=%s", e->name);
+ list_add_tail(&e->list, &counter_list);
+ /* The entry having a refcount of 1 is not directly destructible.
+ * This func has not yet returned the new entry, thus iptables
+ * has not references for destroying this entry.
+ * For another rule to try to destroy it, it would 1st need for this
+ * func* to be re-invoked, acquire a new ref for the same named quota.
+ * Nobody will access the e->procfs_entry either.
+ * So release the lock. */
+ spin_unlock_bh(&counter_list_lock);
- e = q2_new_counter(q, false);
- if (e == NULL)
- goto out;
-
+ /* create_proc_entry() is not spin_lock happy */
p = e->procfs_entry = create_proc_entry(e->name, quota_list_perms,
proc_xt_quota);
- if (p == NULL || IS_ERR(p))
- goto out;
-#if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 29)
- p->owner = THIS_MODULE;
-#endif
+ if (IS_ERR_OR_NULL(p)) {
+ spin_lock_bh(&counter_list_lock);
+ list_del(&e->list);
+ spin_unlock_bh(&counter_list_lock);
+ goto out;
+ }
p->data = e;
p->read_proc = quota_proc_read;
p->write_proc = quota_proc_write;
p->uid = quota_list_uid;
p->gid = quota_list_gid;
- list_add_tail(&e->list, &counter_list);
- spin_unlock_bh(&counter_list_lock);
return e;
out:
- spin_unlock_bh(&counter_list_lock);
kfree(e);
return NULL;
}
@@ -148,6 +161,8 @@ static int quota_mt2_check(const struct xt_mtchk_param *par)
{
struct xt_quota_mtinfo2 *q = par->matchinfo;
+ pr_debug("xt_quota2: check() flags=0x%04x", q->flags);
+
if (q->flags & ~XT_QUOTA_MASK)
return -EINVAL;
@@ -203,7 +218,6 @@ quota_mt2(const struct sk_buff *skb, struct xt_action_param *par)
*/
if (!(q->flags & XT_QUOTA_NO_CHANGE)) {
e->quota += (q->flags & XT_QUOTA_PACKET) ? 1 : skb->len;
- q->quota = e->quota;
}
ret = true;
} else {
@@ -215,7 +229,6 @@ quota_mt2(const struct sk_buff *skb, struct xt_action_param *par)
/* we do not allow even small packets from now on */
e->quota = 0;
}
- q->quota = e->quota;
}
spin_unlock_bh(&e->lock);
return ret;
@@ -228,7 +241,7 @@ static struct xt_match quota_mt2_reg[] __read_mostly = {
.family = NFPROTO_IPV4,
.checkentry = quota_mt2_check,
.match = quota_mt2,
- .destroy = quota_mt2_destroy,
+ .destroy = quota_mt2_destroy,
.matchsize = sizeof(struct xt_quota_mtinfo2),
.me = THIS_MODULE,
},
@@ -238,7 +251,7 @@ static struct xt_match quota_mt2_reg[] __read_mostly = {
.family = NFPROTO_IPV6,
.checkentry = quota_mt2_check,
.match = quota_mt2,
- .destroy = quota_mt2_destroy,
+ .destroy = quota_mt2_destroy,
.matchsize = sizeof(struct xt_quota_mtinfo2),
.me = THIS_MODULE,
},
@@ -247,21 +260,23 @@ static struct xt_match quota_mt2_reg[] __read_mostly = {
static int __init quota_mt2_init(void)
{
int ret;
+ pr_debug("xt_quota2: init()");
- proc_xt_quota = proc_mkdir("xt_quota", init_net__proc_net);
+ proc_xt_quota = proc_mkdir("xt_quota", init_net.proc_net);
if (proc_xt_quota == NULL)
return -EACCES;
ret = xt_register_matches(quota_mt2_reg, ARRAY_SIZE(quota_mt2_reg));
if (ret < 0)
- remove_proc_entry("xt_quota", init_net__proc_net);
+ remove_proc_entry("xt_quota", init_net.proc_net);
+ pr_debug("xt_quota2: init() %d", ret);
return ret;
}
static void __exit quota_mt2_exit(void)
{
xt_unregister_matches(quota_mt2_reg, ARRAY_SIZE(quota_mt2_reg));
- remove_proc_entry("xt_quota", init_net__proc_net);
+ remove_proc_entry("xt_quota", init_net.proc_net);
}
module_init(quota_mt2_init);