diff mbox series

[net-next,v2,2/5] net: openvswitch: set max limitation to meters

Message ID 1587032223-49460-3-git-send-email-xiangxia.m.yue@gmail.com
State Changes Requested
Delegated to: David Miller
Headers show
Series expand meter tables and fix bug | expand

Commit Message

Tonghao Zhang April 16, 2020, 10:17 a.m. UTC 
From: Tonghao Zhang <xiangxia.m.yue@gmail.com>

Don't allow user to create meter unlimitedly,
which may cause to consume a large amount of kernel memory.
The 200,000 meters may be fine in general case.

Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Andy Zhou <azhou@ovn.org>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
---
 net/openvswitch/meter.c | 21 +++++++++++++++------
 net/openvswitch/meter.h |  1 +
 2 files changed, 16 insertions(+), 6 deletions(-)

Comments

Pravin Shelar April 19, 2020, 5:30 p.m. UTC | #1 
On Sat, Apr 18, 2020 at 10:25 AM <xiangxia.m.yue@gmail.com> wrote:
>
> From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
>
> Don't allow user to create meter unlimitedly,
> which may cause to consume a large amount of kernel memory.
> The 200,000 meters may be fine in general case.
>
> Cc: Pravin B Shelar <pshelar@ovn.org>
> Cc: Andy Zhou <azhou@ovn.org>
> Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> ---
>  net/openvswitch/meter.c | 21 +++++++++++++++------
>  net/openvswitch/meter.h |  1 +
>  2 files changed, 16 insertions(+), 6 deletions(-)
>
> diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c
> index 494a0014ecd8..1b6776f9c109 100644
> --- a/net/openvswitch/meter.c
> +++ b/net/openvswitch/meter.c
> @@ -137,6 +137,7 @@ static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
>  {
>         struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
>         u32 hash = meter_hash(ti, meter->id);
> +       int err;
>
>         /*
>          * In generally, slot selected should be empty, because
> @@ -148,16 +149,24 @@ static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
>         dp_meter_instance_insert(ti, meter);
>
>         /* That function is thread-safe. */
> -       if (++tbl->count >= ti->n_meters)
> -               if (dp_meter_instance_realloc(tbl, ti->n_meters * 2))
> -                       goto expand_err;
> +       tbl->count++;
> +       if (tbl->count > DP_METER_NUM_MAX) {
> +               err = -EFBIG;
> +               goto attach_err;
> +       }
> +
> +       if (tbl->count >= ti->n_meters &&
> +           dp_meter_instance_realloc(tbl, ti->n_meters * 2)) {
> +               err = -ENOMEM;
> +               goto attach_err;
> +       }
>
>         return 0;
>
> -expand_err:
> +attach_err:
>         dp_meter_instance_remove(ti, meter);
>         tbl->count--;
> -       return -ENOMEM;
> +       return err;
>  }
>
>  static void detach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> @@ -264,7 +273,7 @@ static int ovs_meter_cmd_features(struct sk_buff *skb, struct genl_info *info)
>         if (IS_ERR(reply))
>                 return PTR_ERR(reply);
>
> -       if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, U32_MAX) ||
> +       if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, DP_METER_NUM_MAX) ||
>             nla_put_u32(reply, OVS_METER_ATTR_MAX_BANDS, DP_MAX_BANDS))
>                 goto nla_put_failure;
>
> diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h
> index d91940383bbe..cdfc6b9dbd42 100644
> --- a/net/openvswitch/meter.h
> +++ b/net/openvswitch/meter.h
> @@ -19,6 +19,7 @@ struct datapath;
>
>  #define DP_MAX_BANDS           1
>  #define DP_METER_ARRAY_SIZE_MIN        (1ULL << 10)
> +#define DP_METER_NUM_MAX       (200000ULL)
>
Lets make it configurable and default could 200k to allow
customization on different memory configurations.


>  struct dp_meter_band {
>         u32 type;
> --
> 2.23.0
>
Tonghao Zhang April 20, 2020, 12:28 a.m. UTC | #2 
On Mon, Apr 20, 2020 at 1:31 AM Pravin Shelar <pravin.ovn@gmail.com> wrote:
>
> On Sat, Apr 18, 2020 at 10:25 AM <xiangxia.m.yue@gmail.com> wrote:
> >
> > From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> >
> > Don't allow user to create meter unlimitedly,
> > which may cause to consume a large amount of kernel memory.
> > The 200,000 meters may be fine in general case.
> >
> > Cc: Pravin B Shelar <pshelar@ovn.org>
> > Cc: Andy Zhou <azhou@ovn.org>
> > Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> > ---
> >  net/openvswitch/meter.c | 21 +++++++++++++++------
> >  net/openvswitch/meter.h |  1 +
> >  2 files changed, 16 insertions(+), 6 deletions(-)
> >
> > diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c
> > index 494a0014ecd8..1b6776f9c109 100644
> > --- a/net/openvswitch/meter.c
> > +++ b/net/openvswitch/meter.c
> > @@ -137,6 +137,7 @@ static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> >  {
> >         struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
> >         u32 hash = meter_hash(ti, meter->id);
> > +       int err;
> >
> >         /*
> >          * In generally, slot selected should be empty, because
> > @@ -148,16 +149,24 @@ static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> >         dp_meter_instance_insert(ti, meter);
> >
> >         /* That function is thread-safe. */
> > -       if (++tbl->count >= ti->n_meters)
> > -               if (dp_meter_instance_realloc(tbl, ti->n_meters * 2))
> > -                       goto expand_err;
> > +       tbl->count++;
> > +       if (tbl->count > DP_METER_NUM_MAX) {
> > +               err = -EFBIG;
> > +               goto attach_err;
> > +       }
> > +
> > +       if (tbl->count >= ti->n_meters &&
> > +           dp_meter_instance_realloc(tbl, ti->n_meters * 2)) {
> > +               err = -ENOMEM;
> > +               goto attach_err;
> > +       }
> >
> >         return 0;
> >
> > -expand_err:
> > +attach_err:
> >         dp_meter_instance_remove(ti, meter);
> >         tbl->count--;
> > -       return -ENOMEM;
> > +       return err;
> >  }
> >
> >  static void detach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> > @@ -264,7 +273,7 @@ static int ovs_meter_cmd_features(struct sk_buff *skb, struct genl_info *info)
> >         if (IS_ERR(reply))
> >                 return PTR_ERR(reply);
> >
> > -       if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, U32_MAX) ||
> > +       if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, DP_METER_NUM_MAX) ||
> >             nla_put_u32(reply, OVS_METER_ATTR_MAX_BANDS, DP_MAX_BANDS))
> >                 goto nla_put_failure;
> >
> > diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h
> > index d91940383bbe..cdfc6b9dbd42 100644
> > --- a/net/openvswitch/meter.h
> > +++ b/net/openvswitch/meter.h
> > @@ -19,6 +19,7 @@ struct datapath;
> >
> >  #define DP_MAX_BANDS           1
> >  #define DP_METER_ARRAY_SIZE_MIN        (1ULL << 10)
> > +#define DP_METER_NUM_MAX       (200000ULL)
> >
> Lets make it configurable and default could 200k to allow
> customization on different memory configurations.
Great, set different limit depend on current system memory size like tcp ?
>
> >  struct dp_meter_band {
> >         u32 type;
> > --
> > 2.23.0
> >
Pravin Shelar April 20, 2020, 9:44 p.m. UTC | #3 
On Sun, Apr 19, 2020 at 5:28 PM Tonghao Zhang <xiangxia.m.yue@gmail.com> wrote:
>
> On Mon, Apr 20, 2020 at 1:31 AM Pravin Shelar <pravin.ovn@gmail.com> wrote:
> >
> > On Sat, Apr 18, 2020 at 10:25 AM <xiangxia.m.yue@gmail.com> wrote:
> > >
> > > From: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> > >
> > > Don't allow user to create meter unlimitedly,
> > > which may cause to consume a large amount of kernel memory.
> > > The 200,000 meters may be fine in general case.
> > >
> > > Cc: Pravin B Shelar <pshelar@ovn.org>
> > > Cc: Andy Zhou <azhou@ovn.org>
> > > Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
> > > ---
> > >  net/openvswitch/meter.c | 21 +++++++++++++++------
> > >  net/openvswitch/meter.h |  1 +
> > >  2 files changed, 16 insertions(+), 6 deletions(-)
> > >
> > > diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c
> > > index 494a0014ecd8..1b6776f9c109 100644
> > > --- a/net/openvswitch/meter.c
> > > +++ b/net/openvswitch/meter.c
> > > @@ -137,6 +137,7 @@ static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> > >  {
> > >         struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
> > >         u32 hash = meter_hash(ti, meter->id);
> > > +       int err;
> > >
> > >         /*
> > >          * In generally, slot selected should be empty, because
> > > @@ -148,16 +149,24 @@ static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> > >         dp_meter_instance_insert(ti, meter);
> > >
> > >         /* That function is thread-safe. */
> > > -       if (++tbl->count >= ti->n_meters)
> > > -               if (dp_meter_instance_realloc(tbl, ti->n_meters * 2))
> > > -                       goto expand_err;
> > > +       tbl->count++;
> > > +       if (tbl->count > DP_METER_NUM_MAX) {
> > > +               err = -EFBIG;
> > > +               goto attach_err;
> > > +       }
> > > +
> > > +       if (tbl->count >= ti->n_meters &&
> > > +           dp_meter_instance_realloc(tbl, ti->n_meters * 2)) {
> > > +               err = -ENOMEM;
> > > +               goto attach_err;
> > > +       }
> > >
> > >         return 0;
> > >
> > > -expand_err:
> > > +attach_err:
> > >         dp_meter_instance_remove(ti, meter);
> > >         tbl->count--;
> > > -       return -ENOMEM;
> > > +       return err;
> > >  }
> > >
> > >  static void detach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
> > > @@ -264,7 +273,7 @@ static int ovs_meter_cmd_features(struct sk_buff *skb, struct genl_info *info)
> > >         if (IS_ERR(reply))
> > >                 return PTR_ERR(reply);
> > >
> > > -       if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, U32_MAX) ||
> > > +       if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, DP_METER_NUM_MAX) ||
> > >             nla_put_u32(reply, OVS_METER_ATTR_MAX_BANDS, DP_MAX_BANDS))
> > >                 goto nla_put_failure;
> > >
> > > diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h
> > > index d91940383bbe..cdfc6b9dbd42 100644
> > > --- a/net/openvswitch/meter.h
> > > +++ b/net/openvswitch/meter.h
> > > @@ -19,6 +19,7 @@ struct datapath;
> > >
> > >  #define DP_MAX_BANDS           1
> > >  #define DP_METER_ARRAY_SIZE_MIN        (1ULL << 10)
> > > +#define DP_METER_NUM_MAX       (200000ULL)
> > >
> > Lets make it configurable and default could 200k to allow
> > customization on different memory configurations.
> Great, set different limit depend on current system memory size like tcp ?

Yes. that could be useful.
diff mbox series

Patch

diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c
index 494a0014ecd8..1b6776f9c109 100644
--- a/net/openvswitch/meter.c
+++ b/net/openvswitch/meter.c
@@ -137,6 +137,7 @@  static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
 {
 	struct dp_meter_instance *ti = rcu_dereference_ovsl(tbl->ti);
 	u32 hash = meter_hash(ti, meter->id);
+	int err;
 
 	/*
 	 * In generally, slot selected should be empty, because
@@ -148,16 +149,24 @@  static int attach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
 	dp_meter_instance_insert(ti, meter);
 
 	/* That function is thread-safe. */
-	if (++tbl->count >= ti->n_meters)
-		if (dp_meter_instance_realloc(tbl, ti->n_meters * 2))
-			goto expand_err;
+	tbl->count++;
+	if (tbl->count > DP_METER_NUM_MAX) {
+		err = -EFBIG;
+		goto attach_err;
+	}
+
+	if (tbl->count >= ti->n_meters &&
+	    dp_meter_instance_realloc(tbl, ti->n_meters * 2)) {
+		err = -ENOMEM;
+		goto attach_err;
+	}
 
 	return 0;
 
-expand_err:
+attach_err:
 	dp_meter_instance_remove(ti, meter);
 	tbl->count--;
-	return -ENOMEM;
+	return err;
 }
 
 static void detach_meter(struct dp_meter_table *tbl, struct dp_meter *meter)
@@ -264,7 +273,7 @@  static int ovs_meter_cmd_features(struct sk_buff *skb, struct genl_info *info)
 	if (IS_ERR(reply))
 		return PTR_ERR(reply);
 
-	if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, U32_MAX) ||
+	if (nla_put_u32(reply, OVS_METER_ATTR_MAX_METERS, DP_METER_NUM_MAX) ||
 	    nla_put_u32(reply, OVS_METER_ATTR_MAX_BANDS, DP_MAX_BANDS))
 		goto nla_put_failure;
 
diff --git a/net/openvswitch/meter.h b/net/openvswitch/meter.h
index d91940383bbe..cdfc6b9dbd42 100644
--- a/net/openvswitch/meter.h
+++ b/net/openvswitch/meter.h
@@ -19,6 +19,7 @@  struct datapath;
 
 #define DP_MAX_BANDS		1
 #define DP_METER_ARRAY_SIZE_MIN	(1ULL << 10)
+#define DP_METER_NUM_MAX	(200000ULL)
 
 struct dp_meter_band {
 	u32 type;