[PATCH net-2.6] bonding: correctly process LACPDUs in non-linear skbs

[PATCH net-2.6] bonding: correctly process LACPDUs in non-linear skbs

[Andy Gospodarek]

It was recently brought to my attention that 802.3ad mode bonds would no
longer form when using some network hardware after a driver update.
After snooping around I realized that the particular hardware was using
page-based skbs and found that skb->data did not contain a valid LACPDU
as it wasn't stored there.  That explained the inability to form an
802.3ad-based bond.

This patch fixes the issue in my tests and should be applied to 2.6.36
and as far back as anyone cares to add it to stable.

Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.

Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
CC: stable@kernel.org

---
 drivers/net/bonding/bond_3ad.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 822f586..0ddf4c6 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -2466,6 +2466,9 @@ int bond_3ad_lacpdu_recv(struct sk_buff *skb, struct net_device *dev, struct pac
 	if (!(dev->flags & IFF_MASTER))
 		goto out;
 
+	if (!pskb_may_pull(skb, sizeof(struct lacpdu)))
+		goto out;
+
 	read_lock(&bond->lock);
 	slave = bond_get_slave_by_dev((struct bonding *)netdev_priv(dev),
 					orig_dev);
-- 
1.7.0.1

Re: [PATCH net-2.6] bonding: correctly process LACPDUs in non-linear skbs

[Jay Vosburgh]

Andy Gospodarek <andy@greyhouse.net> wrote:

>
>It was recently brought to my attention that 802.3ad mode bonds would no
>longer form when using some network hardware after a driver update.
>After snooping around I realized that the particular hardware was using
>page-based skbs and found that skb->data did not contain a valid LACPDU
>as it wasn't stored there.  That explained the inability to form an
>802.3ad-based bond.
>
>This patch fixes the issue in my tests and should be applied to 2.6.36
>and as far back as anyone cares to add it to stable.
>
>Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
>Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.
>
>Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
>CC: Alexander Duyck <alexander.h.duyck@intel.com>
>CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
>CC: stable@kernel.org

	Did you by any chance also test balance-alb mode?  Inspection
suggests that rlb_arp_recv may suffer from the same problem.

	If you agree, could you add that to the patch and resubmit it?

	Either way, the patch looks good.

	-J

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>


>---
> drivers/net/bonding/bond_3ad.c |    3 +++
> 1 files changed, 3 insertions(+), 0 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
>index 822f586..0ddf4c6 100644
>--- a/drivers/net/bonding/bond_3ad.c
>+++ b/drivers/net/bonding/bond_3ad.c
>@@ -2466,6 +2466,9 @@ int bond_3ad_lacpdu_recv(struct sk_buff *skb, struct net_device *dev, struct pac
> 	if (!(dev->flags & IFF_MASTER))
> 		goto out;
>
>+	if (!pskb_may_pull(skb, sizeof(struct lacpdu)))
>+		goto out;
>+
> 	read_lock(&bond->lock);
> 	slave = bond_get_slave_by_dev((struct bonding *)netdev_priv(dev),
> 					orig_dev);
>-- 
>1.7.0.1
>
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Re: [PATCH net-2.6 v2] bonding: correctly process non-linear skbs

[Andy Gospodarek]

On Fri, Sep 10, 2010 at 02:04:00PM -0700, Jay Vosburgh wrote:
> Andy Gospodarek <andy@greyhouse.net> wrote:
> 
> >
> >It was recently brought to my attention that 802.3ad mode bonds would no
> >longer form when using some network hardware after a driver update.
> >After snooping around I realized that the particular hardware was using
> >page-based skbs and found that skb->data did not contain a valid LACPDU
> >as it wasn't stored there.  That explained the inability to form an
> >802.3ad-based bond.
> >
> >This patch fixes the issue in my tests and should be applied to 2.6.36
> >and as far back as anyone cares to add it to stable.
> >
> >Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
> >Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.
> >
> >Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
> >CC: Alexander Duyck <alexander.h.duyck@intel.com>
> >CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
> >CC: stable@kernel.org
> 
> 	Did you by any chance also test balance-alb mode?  Inspection
> suggests that rlb_arp_recv may suffer from the same problem.
> 
> 	If you agree, could you add that to the patch and resubmit it?
> 
> 	Either way, the patch looks good.
> 

You are correct, Jay.  I did a quick test and confirmed that ARPs might
not be properly processed when using balance-ALB too.  Below is a patch
to fix both spots:


[PATCH net-2.6 v2] bonding: correctly process non-linear skbs

It was recently brought to my attention that 802.3ad mode bonds would no
longer form when using some network hardware after a driver update.
After snooping around I realized that the particular hardware was using
page-based skbs and found that skb->data did not contain a valid LACPDU
as it was not stored there.  That explained the inability to form an
802.3ad-based bond.  For balance-alb mode bonds this was also an issue
as ARPs would not be properly processed.

This patch fixes the issue in my tests and should be applied to 2.6.36
and as far back as anyone cares to add it to stable.

Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.

Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
CC: Alexander Duyck <alexander.h.duyck@intel.com>
CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
CC: stable@kerne.org

---
 drivers/net/bonding/bond_3ad.c |    3 +++
 drivers/net/bonding/bond_alb.c |    3 +++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 822f586..0ddf4c6 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -2466,6 +2466,9 @@ int bond_3ad_lacpdu_recv(struct sk_buff *skb, struct net_device *dev, struct pac
 	if (!(dev->flags & IFF_MASTER))
 		goto out;
 
+	if (!pskb_may_pull(skb, sizeof(struct lacpdu)))
+		goto out;
+
 	read_lock(&bond->lock);
 	slave = bond_get_slave_by_dev((struct bonding *)netdev_priv(dev),
 					orig_dev);
diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
index c746b33..26bb118 100644
--- a/drivers/net/bonding/bond_alb.c
+++ b/drivers/net/bonding/bond_alb.c
@@ -362,6 +362,9 @@ static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct
 		goto out;
 	}
 
+	if (!pskb_may_pull(skb, arp_hdr_len(bond_dev)))
+		goto out;
+
 	if (skb->len < sizeof(struct arp_pkt)) {
 		pr_debug("Packet is too small to be an ARP\n");
 		goto out;

-- 
1.7.0.1

Re: [PATCH net-2.6 v2] bonding: correctly process non-linear skbs

[Jay Vosburgh]

Andy Gospodarek <andy@greyhouse.net> wrote:

>On Fri, Sep 10, 2010 at 02:04:00PM -0700, Jay Vosburgh wrote:
>> Andy Gospodarek <andy@greyhouse.net> wrote:
>> 
>> >
>> >It was recently brought to my attention that 802.3ad mode bonds would no
>> >longer form when using some network hardware after a driver update.
>> >After snooping around I realized that the particular hardware was using
>> >page-based skbs and found that skb->data did not contain a valid LACPDU
>> >as it wasn't stored there.  That explained the inability to form an
>> >802.3ad-based bond.
>> >
>> >This patch fixes the issue in my tests and should be applied to 2.6.36
>> >and as far back as anyone cares to add it to stable.
>> >
>> >Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
>> >Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.
>> >
>> >Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
>> >CC: Alexander Duyck <alexander.h.duyck@intel.com>
>> >CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
>> >CC: stable@kernel.org
>> 
>> 	Did you by any chance also test balance-alb mode?  Inspection
>> suggests that rlb_arp_recv may suffer from the same problem.
>> 
>> 	If you agree, could you add that to the patch and resubmit it?
>> 
>> 	Either way, the patch looks good.
>> 
>
>You are correct, Jay.  I did a quick test and confirmed that ARPs might
>not be properly processed when using balance-ALB too.  Below is a patch
>to fix both spots:
>
>
>[PATCH net-2.6 v2] bonding: correctly process non-linear skbs
>
>It was recently brought to my attention that 802.3ad mode bonds would no
>longer form when using some network hardware after a driver update.
>After snooping around I realized that the particular hardware was using
>page-based skbs and found that skb->data did not contain a valid LACPDU
>as it was not stored there.  That explained the inability to form an
>802.3ad-based bond.  For balance-alb mode bonds this was also an issue
>as ARPs would not be properly processed.
>
>This patch fixes the issue in my tests and should be applied to 2.6.36
>and as far back as anyone cares to add it to stable.
>
>Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
>Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.
>
>Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
>CC: Alexander Duyck <alexander.h.duyck@intel.com>
>CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
>CC: stable@kerne.org

Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>


>---
> drivers/net/bonding/bond_3ad.c |    3 +++
> drivers/net/bonding/bond_alb.c |    3 +++
> 2 files changed, 6 insertions(+), 0 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
>index 822f586..0ddf4c6 100644
>--- a/drivers/net/bonding/bond_3ad.c
>+++ b/drivers/net/bonding/bond_3ad.c
>@@ -2466,6 +2466,9 @@ int bond_3ad_lacpdu_recv(struct sk_buff *skb, struct net_device *dev, struct pac
> 	if (!(dev->flags & IFF_MASTER))
> 		goto out;
>
>+	if (!pskb_may_pull(skb, sizeof(struct lacpdu)))
>+		goto out;
>+
> 	read_lock(&bond->lock);
> 	slave = bond_get_slave_by_dev((struct bonding *)netdev_priv(dev),
> 					orig_dev);
>diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
>index c746b33..26bb118 100644
>--- a/drivers/net/bonding/bond_alb.c
>+++ b/drivers/net/bonding/bond_alb.c
>@@ -362,6 +362,9 @@ static int rlb_arp_recv(struct sk_buff *skb, struct net_device *bond_dev, struct
> 		goto out;
> 	}
>
>+	if (!pskb_may_pull(skb, arp_hdr_len(bond_dev)))
>+		goto out;
>+
> 	if (skb->len < sizeof(struct arp_pkt)) {
> 		pr_debug("Packet is too small to be an ARP\n");
> 		goto out;
>
>-- 
>1.7.0.1
>

Re: [PATCH net-2.6 v2] bonding: correctly process non-linear skbs

[David Miller]

From: Jay Vosburgh <fubar@us.ibm.com>
Date: Fri, 10 Sep 2010 18:08:35 -0700

> Andy Gospodarek <andy@greyhouse.net> wrote:
>>[PATCH net-2.6 v2] bonding: correctly process non-linear skbs
>>
>>It was recently brought to my attention that 802.3ad mode bonds would no
>>longer form when using some network hardware after a driver update.
>>After snooping around I realized that the particular hardware was using
>>page-based skbs and found that skb->data did not contain a valid LACPDU
>>as it was not stored there.  That explained the inability to form an
>>802.3ad-based bond.  For balance-alb mode bonds this was also an issue
>>as ARPs would not be properly processed.
>>
>>This patch fixes the issue in my tests and should be applied to 2.6.36
>>and as far back as anyone cares to add it to stable.
>>
>>Thanks to Alexander Duyck <alexander.h.duyck@intel.com> and Jesse
>>Brandeburg <jesse.brandeburg@intel.com> for the suggestions on this one.
>>
>>Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
>>CC: Alexander Duyck <alexander.h.duyck@intel.com>
>>CC: Jesse Brandeburg <jesse.brandeburg@intel.com>
>>CC: stable@kerne.org
> 
> Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
> 

Applied, thanks everyone.