[PATCH bluetooth-next 0/4] ieee802154: mrf24j40 cleanups and 6lowpan fix

[PATCH bluetooth-next 0/4] ieee802154: mrf24j40 cleanups and 6lowpan fix

[Alexander Aring]

Hi,

this patches series contains cleanups for the mrf24j40 driver of the 802.15.4 subsystem.
Also one patch to fix a 802.15.4 6LoWPAN bug if we replace the IPv6 header with 6LoWPAN
header on a shared skb data buffer.

- Alex

Simon Vincent (1):
  ieee802154: 6lowpan: ensure header compression does not corrupt ipv6
    header

Varka Bhadram (3):
  mrf24j40: fix Missing a blank line after declarations
  mrf24j40: remove unnecessary return statement
  mrf24j40: use pr_* / dev_* instead of printk()

 drivers/net/ieee802154/mrf24j40.c |  19 +++---
 net/ieee802154/6lowpan_rtnl.c     | 125 +++++++++++++++++++++++++++-----------
 2 files changed, 99 insertions(+), 45 deletions(-)

-- 
2.1.0

[PATCH bluetooth-next 1/4] mrf24j40: fix Missing a blank line after declarations

[Alexander Aring]

From: Varka Bhadram <varkabhadram@gmail.com>

Signed-off-by: Varka Bhadram <varkab@cdac.in>
Acked-by: Alan Ott <alan@signal11.us>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 drivers/net/ieee802154/mrf24j40.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ieee802154/mrf24j40.c b/drivers/net/ieee802154/mrf24j40.c
index 9e6a124..466da57 100644
--- a/drivers/net/ieee802154/mrf24j40.c
+++ b/drivers/net/ieee802154/mrf24j40.c
@@ -412,6 +412,7 @@ static void mrf24j40_stop(struct ieee802154_dev *dev)
 	struct mrf24j40 *devrec = dev->priv;
 	u8 val;
 	int ret;
+
 	dev_dbg(printdev(devrec), "stop\n");
 
 	ret = read_short_reg(devrec, REG_INTCON, &val);
@@ -465,6 +466,7 @@ static int mrf24j40_filter(struct ieee802154_dev *dev,
 	if (changed & IEEE802515_AFILT_SADDR_CHANGED) {
 		/* Short Addr */
 		u8 addrh, addrl;
+
 		addrh = le16_to_cpu(filt->short_addr) >> 8 & 0xff;
 		addrl = le16_to_cpu(filt->short_addr) & 0xff;
 
@@ -493,6 +495,7 @@ static int mrf24j40_filter(struct ieee802154_dev *dev,
 	if (changed & IEEE802515_AFILT_PANID_CHANGED) {
 		/* PAN ID */
 		u8 panidl, panidh;
+
 		panidh = le16_to_cpu(filt->pan_id) >> 8 & 0xff;
 		panidl = le16_to_cpu(filt->pan_id) & 0xff;
 		write_short_reg(devrec, REG_PANIDH, panidh);
-- 
2.1.0

[PATCH bluetooth-next 2/4] mrf24j40: remove unnecessary return statement

[Alexander Aring]

From: Varka Bhadram <varkabhadram@gmail.com>

Remove the return statement in the void function.

Signed-off-by: Varka Bhadram <varkab@cdac.in>
Acked-by: Alan Ott <alan@signal11.us>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 drivers/net/ieee802154/mrf24j40.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/ieee802154/mrf24j40.c b/drivers/net/ieee802154/mrf24j40.c
index 466da57..2c617e3 100644
--- a/drivers/net/ieee802154/mrf24j40.c
+++ b/drivers/net/ieee802154/mrf24j40.c
@@ -420,8 +420,6 @@ static void mrf24j40_stop(struct ieee802154_dev *dev)
 		return;
 	val |= 0x1|0x8; /* Set TXNIE and RXIE. Disable Interrupts */
 	write_short_reg(devrec, REG_INTCON, val);
-
-	return;
 }
 
 static int mrf24j40_set_channel(struct ieee802154_dev *dev,
-- 
2.1.0

[PATCH bluetooth-next 3/4] mrf24j40: use pr_* / dev_* instead of printk()

[Alexander Aring]

From: Varka Bhadram <varkabhadram@gmail.com>

Replace printk() with dev_*() pr_*().

Signed-off-by: Varka Bhadram <varkab@cdac.in>
Acked-by: Alan Ott <alan@signal11.us>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 drivers/net/ieee802154/mrf24j40.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ieee802154/mrf24j40.c b/drivers/net/ieee802154/mrf24j40.c
index 2c617e3..07e0b88 100644
--- a/drivers/net/ieee802154/mrf24j40.c
+++ b/drivers/net/ieee802154/mrf24j40.c
@@ -323,8 +323,8 @@ static int mrf24j40_read_rx_buf(struct mrf24j40 *devrec,
 #ifdef DEBUG
 	print_hex_dump(KERN_DEBUG, "mrf24j40 rx: ",
 		DUMP_PREFIX_OFFSET, 16, 1, data, *len, 0);
-	printk(KERN_DEBUG "mrf24j40 rx: lqi: %02hhx rssi: %02hhx\n",
-		lqi_rssi[0], lqi_rssi[1]);
+	pr_debug("mrf24j40 rx: lqi: %02hhx rssi: %02hhx\n",
+		 lqi_rssi[0], lqi_rssi[1]);
 #endif
 
 out:
@@ -385,7 +385,7 @@ err:
 static int mrf24j40_ed(struct ieee802154_dev *dev, u8 *level)
 {
 	/* TODO: */
-	printk(KERN_WARNING "mrf24j40: ed not implemented\n");
+	pr_warn("mrf24j40: ed not implemented\n");
 	*level = 0;
 	return 0;
 }
@@ -483,10 +483,10 @@ static int mrf24j40_filter(struct ieee802154_dev *dev,
 			write_short_reg(devrec, REG_EADR0 + i, addr[i]);
 
 #ifdef DEBUG
-		printk(KERN_DEBUG "Set long addr to: ");
+		pr_debug("Set long addr to: ");
 		for (i = 0; i < 8; i++)
-			printk("%02hhx ", addr[7 - i]);
-		printk(KERN_DEBUG "\n");
+			pr_debug("%02hhx ", addr[7 - i]);
+		pr_debug("\n");
 #endif
 	}
 
@@ -702,7 +702,7 @@ static int mrf24j40_probe(struct spi_device *spi)
 	int ret = -ENOMEM;
 	struct mrf24j40 *devrec;
 
-	printk(KERN_INFO "mrf24j40: probe(). IRQ: %d\n", spi->irq);
+	dev_info(&spi->dev, "probe(). IRQ: %d\n", spi->irq);
 
 	devrec = devm_kzalloc(&spi->dev, sizeof(struct mrf24j40), GFP_KERNEL);
 	if (!devrec)
-- 
2.1.0

[PATCH bluetooth-next 4/4] ieee802154: 6lowpan: ensure header compression does not corrupt ipv6 header

[Alexander Aring]

From: Simon Vincent <simon.vincent@xsilon.com>

The 6lowpan ipv6 header compression was causing problems for other interfaces
that expected a ipv6 header to still be in place, as we were replacing the
ipv6 header with a compressed version. This happened if you sent a packet to a
multicast address as the packet would be output on 802.15.4, ethernet, and also
be sent to the loopback interface. The skb data was shared between these
interfaces so all interfaces ended up with a compressed ipv6 header.
The solution is to ensure that before we do any header compression we are not
sharing the skb or skb data with any other interface. If we are then we must
take a copy of the skb and skb data before modifying the ipv6 header.
The only place we can copy the skb is inside the xmit function so we don't
leave dangling references to skb.
This patch moves all the header compression to inside the xmit function. Very
little code has been changed it has mostly been moved from lowpan_header_create
to lowpan_xmit. At the top of the xmit function we now check if the skb is
shared and if so copy it. In lowpan_header_create all we do now is store the
source and destination addresses for use later when we compress the header.

Signed-off-by: Simon Vincent <simon.vincent@xsilon.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
---
 net/ieee802154/6lowpan_rtnl.c | 125 ++++++++++++++++++++++++++++++------------
 1 file changed, 89 insertions(+), 36 deletions(-)

diff --git a/net/ieee802154/6lowpan_rtnl.c b/net/ieee802154/6lowpan_rtnl.c
index 5e788cd..78cb206 100644
--- a/net/ieee802154/6lowpan_rtnl.c
+++ b/net/ieee802154/6lowpan_rtnl.c
@@ -71,20 +71,42 @@ struct lowpan_dev_record {
 	struct list_head list;
 };
 
+/* don't save pan id, it's intra pan */
+struct lowpan_addr {
+	u8 mode;
+	union lowpan_addr_u {
+		/* IPv6 needs big endian here */
+		__be64 extended_addr;
+		__be16 short_addr;
+	} u;
+};
+
+struct lowpan_addr_info {
+	struct lowpan_addr daddr;
+	struct lowpan_addr saddr;
+};
+
 static inline struct
 lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
 {
 	return netdev_priv(dev);
 }
 
+static inline struct
+lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
+{
+	WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
+	return (struct lowpan_addr_info *)(skb->data -
+			sizeof(struct lowpan_addr_info));
+}
+
 static int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
 				unsigned short type, const void *_daddr,
 				const void *_saddr, unsigned int len)
 {
 	const u8 *saddr = _saddr;
 	const u8 *daddr = _daddr;
-	struct ieee802154_addr sa, da;
-	struct ieee802154_mac_cb *cb = mac_cb_init(skb);
+	struct lowpan_addr_info *info;
 
 	/* TODO:
 	 * if this package isn't ipv6 one, where should it be routed?
@@ -98,41 +120,17 @@ static int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
 	raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
 	raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
 
-	lowpan_header_compress(skb, dev, type, daddr, saddr, len);
-
-	/* NOTE1: I'm still unsure about the fact that compression and WPAN
-	 * header are created here and not later in the xmit. So wait for
-	 * an opinion of net maintainers.
-	 */
-	/* NOTE2: to be absolutely correct, we must derive PANid information
-	 * from MAC subif of the 'dev' and 'real_dev' network devices, but
-	 * this isn't implemented in mainline yet, so currently we assign 0xff
-	 */
-	cb->type = IEEE802154_FC_TYPE_DATA;
-
-	/* prepare wpan address data */
-	sa.mode = IEEE802154_ADDR_LONG;
-	sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
-	sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
-
-	/* intra-PAN communications */
-	da.pan_id = sa.pan_id;
-
-	/* if the destination address is the broadcast address, use the
-	 * corresponding short address
-	 */
-	if (lowpan_is_addr_broadcast(daddr)) {
-		da.mode = IEEE802154_ADDR_SHORT;
-		da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
-	} else {
-		da.mode = IEEE802154_ADDR_LONG;
-		da.extended_addr = ieee802154_devaddr_from_raw(daddr);
-	}
+	info = lowpan_skb_priv(skb);
 
-	cb->ackreq = !lowpan_is_addr_broadcast(daddr);
+	/* TODO: Currently we only support extended_addr */
+	info->daddr.mode = IEEE802154_ADDR_LONG;
+	memcpy(&info->daddr.u.extended_addr, daddr,
+	       sizeof(info->daddr.u.extended_addr));
+	info->saddr.mode = IEEE802154_ADDR_LONG;
+	memcpy(&info->saddr.u.extended_addr, saddr,
+	       sizeof(info->daddr.u.extended_addr));
 
-	return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
-			type, (void *)&da, (void *)&sa, 0);
+	return 0;
 }
 
 static int lowpan_give_skb_to_devices(struct sk_buff *skb,
@@ -330,13 +328,68 @@ err:
 	return rc;
 }
 
+static int lowpan_header(struct sk_buff *skb, struct net_device *dev)
+{
+	struct ieee802154_addr sa, da;
+	struct ieee802154_mac_cb *cb = mac_cb_init(skb);
+	struct lowpan_addr_info info;
+	void *daddr, *saddr;
+
+	memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
+
+	/* TODO: Currently we only support extended_addr */
+	daddr = &info.daddr.u.extended_addr;
+	saddr = &info.saddr.u.extended_addr;
+
+	lowpan_header_compress(skb, dev, ETH_P_IPV6, daddr, saddr, skb->len);
+
+	cb->type = IEEE802154_FC_TYPE_DATA;
+
+	/* prepare wpan address data */
+	sa.mode = IEEE802154_ADDR_LONG;
+	sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
+	sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
+
+	/* intra-PAN communications */
+	da.pan_id = sa.pan_id;
+
+	/* if the destination address is the broadcast address, use the
+	 * corresponding short address
+	 */
+	if (lowpan_is_addr_broadcast((const u8 *)daddr)) {
+		da.mode = IEEE802154_ADDR_SHORT;
+		da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
+		cb->ackreq = false;
+	} else {
+		da.mode = IEEE802154_ADDR_LONG;
+		da.extended_addr = ieee802154_devaddr_from_raw(daddr);
+		cb->ackreq = true;
+	}
+
+	return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
+			ETH_P_IPV6, (void *)&da, (void *)&sa, 0);
+}
+
 static netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct ieee802154_hdr wpan_hdr;
-	int max_single;
+	int max_single, ret;
 
 	pr_debug("package xmit\n");
 
+	/* We must take a copy of the skb before we modify/replace the ipv6
+	 * header as the header could be used elsewhere
+	 */
+	skb = skb_unshare(skb, GFP_ATOMIC);
+	if (!skb)
+		return NET_XMIT_DROP;
+
+	ret = lowpan_header(skb, dev);
+	if (ret < 0) {
+		kfree_skb(skb);
+		return NET_XMIT_DROP;
+	}
+
 	if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
 		kfree_skb(skb);
 		return NET_XMIT_DROP;
-- 
2.1.0

Re: [PATCH bluetooth-next 4/4] ieee802154: 6lowpan: ensure header compression does not corrupt ipv6 header

[Marcel Holtmann]

Hi Alex,

> The 6lowpan ipv6 header compression was causing problems for other interfaces
> that expected a ipv6 header to still be in place, as we were replacing the
> ipv6 header with a compressed version. This happened if you sent a packet to a
> multicast address as the packet would be output on 802.15.4, ethernet, and also
> be sent to the loopback interface. The skb data was shared between these
> interfaces so all interfaces ended up with a compressed ipv6 header.
> The solution is to ensure that before we do any header compression we are not
> sharing the skb or skb data with any other interface. If we are then we must
> take a copy of the skb and skb data before modifying the ipv6 header.
> The only place we can copy the skb is inside the xmit function so we don't
> leave dangling references to skb.
> This patch moves all the header compression to inside the xmit function. Very
> little code has been changed it has mostly been moved from lowpan_header_create
> to lowpan_xmit. At the top of the xmit function we now check if the skb is
> shared and if so copy it. In lowpan_header_create all we do now is store the
> source and destination addresses for use later when we compress the header.

so I added a two empty lines here to make this text a bit more easier on the eyes when reading it. Also in the future I would propose to keep it a 72 chars and not try to max out the 80 chars width. The reason is so that git log displays properly in a 80 chars terminal.

> 
> Signed-off-by: Simon Vincent <simon.vincent@xsilon.com>
> Signed-off-by: Alexander Aring <alex.aring@gmail.com>
> ---
> net/ieee802154/6lowpan_rtnl.c | 125 ++++++++++++++++++++++++++++++------------
> 1 file changed, 89 insertions(+), 36 deletions(-)
> 
> diff --git a/net/ieee802154/6lowpan_rtnl.c b/net/ieee802154/6lowpan_rtnl.c
> index 5e788cd..78cb206 100644
> --- a/net/ieee802154/6lowpan_rtnl.c
> +++ b/net/ieee802154/6lowpan_rtnl.c
> @@ -71,20 +71,42 @@ struct lowpan_dev_record {
> 	struct list_head list;
> };
> 
> +/* don't save pan id, it's intra pan */
> +struct lowpan_addr {
> +	u8 mode;
> +	union lowpan_addr_u {

I changed this into union { since there is no reason to name the union here.

> +		/* IPv6 needs big endian here */
> +		__be64 extended_addr;
> +		__be16 short_addr;
> +	} u;
> +};

Regards

Marcel

Re: [PATCH bluetooth-next 4/4] ieee802154: 6lowpan: ensure header compression does not corrupt ipv6 header

[Alexander Aring]

On Wed, Sep 24, 2014 at 02:18:52PM +0200, Marcel Holtmann wrote:
> Hi Alex,
> 
> > The 6lowpan ipv6 header compression was causing problems for other interfaces
> > that expected a ipv6 header to still be in place, as we were replacing the
> > ipv6 header with a compressed version. This happened if you sent a packet to a
> > multicast address as the packet would be output on 802.15.4, ethernet, and also
> > be sent to the loopback interface. The skb data was shared between these
> > interfaces so all interfaces ended up with a compressed ipv6 header.
> > The solution is to ensure that before we do any header compression we are not
> > sharing the skb or skb data with any other interface. If we are then we must
> > take a copy of the skb and skb data before modifying the ipv6 header.
> > The only place we can copy the skb is inside the xmit function so we don't
> > leave dangling references to skb.
> > This patch moves all the header compression to inside the xmit function. Very
> > little code has been changed it has mostly been moved from lowpan_header_create
> > to lowpan_xmit. At the top of the xmit function we now check if the skb is
> > shared and if so copy it. In lowpan_header_create all we do now is store the
> > source and destination addresses for use later when we compress the header.
> 
> so I added a two empty lines here to make this text a bit more easier on the eyes when reading it. Also in the future I would propose to keep it a 72 chars and not try to max out the 80 chars width. The reason is so that git log displays properly in a 80 chars terminal.
> 

ok. thanks. Yes, I know the 80 chars width... need to check this when I
see/apply others patches.

> > 
> > Signed-off-by: Simon Vincent <simon.vincent@xsilon.com>
> > Signed-off-by: Alexander Aring <alex.aring@gmail.com>
> > ---
> > net/ieee802154/6lowpan_rtnl.c | 125 ++++++++++++++++++++++++++++++------------
> > 1 file changed, 89 insertions(+), 36 deletions(-)
> > 
> > diff --git a/net/ieee802154/6lowpan_rtnl.c b/net/ieee802154/6lowpan_rtnl.c
> > index 5e788cd..78cb206 100644
> > --- a/net/ieee802154/6lowpan_rtnl.c
> > +++ b/net/ieee802154/6lowpan_rtnl.c
> > @@ -71,20 +71,42 @@ struct lowpan_dev_record {
> > 	struct list_head list;
> > };
> > 
> > +/* don't save pan id, it's intra pan */
> > +struct lowpan_addr {
> > +	u8 mode;
> > +	union lowpan_addr_u {
> 
> I changed this into union { since there is no reason to name the union here.
> 

oops, yes you already said that at your first review note. Seems that
this wasn't changed.

Thanks Marcel.

- Alex

Re: [PATCH bluetooth-next 0/4] ieee802154: mrf24j40 cleanups and 6lowpan fix

[Marcel Holtmann]

Hi Alex,

> this patches series contains cleanups for the mrf24j40 driver of the 802.15.4 subsystem.
> Also one patch to fix a 802.15.4 6LoWPAN bug if we replace the IPv6 header with 6LoWPAN
> header on a shared skb data buffer.
> 
> - Alex
> 
> Simon Vincent (1):
>  ieee802154: 6lowpan: ensure header compression does not corrupt ipv6
>    header
> 
> Varka Bhadram (3):
>  mrf24j40: fix Missing a blank line after declarations
>  mrf24j40: remove unnecessary return statement
>  mrf24j40: use pr_* / dev_* instead of printk()
> 
> drivers/net/ieee802154/mrf24j40.c |  19 +++---
> net/ieee802154/6lowpan_rtnl.c     | 125 +++++++++++++++++++++++++++-----------
> 2 files changed, 99 insertions(+), 45 deletions(-)

all 4 patches have been applied to bluetooth-next tree.

Regards

Marcel