All of lore.kernel.org
 help / color / mirror / Atom feed
From: Wolfgang Grandegger <wg-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org>
To: Linux Netdev List <netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>
Cc: SocketCAN Core Mailing List
	<socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org>,
	Marc Kleine-Budde <mkl-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Subject: [PATCH] can: provide library functions for skb allocation
Date: Thu, 15 Oct 2009 11:22:18 +0200	[thread overview]
Message-ID: <4AD6E9CA.3070605@grandegger.com> (raw)

This patch makes the private functions alloc_can_skb() and
alloc_can_err_skb() of the at91_can driver public and adapts all
drivers  to use these. While making the patch I realized, that the
skb's are *not* setup consistently. It's now done as shown below:

  skb->protocol = __constant_htons(ETH_P_CAN);
  skb->pkt_type = PACKET_BROADCAST;
  skb->ip_summed = CHECKSUM_UNNECESSARY;
  *cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
  memset(*cf, 0, sizeof(struct can_frame));

The frame is zeroed out to avoid uninitialized data to be passed
to user space. Some drivers or library code used "htons(ETH_P_CAN)"
or did not set "pkt_type" or "ip_summed" or did not zero the fame.

Signed-off-by: Wolfgang Grandegger <wg-5Yr1BZd7O62+XT7JhA+gdA@public.gmane.org>
---
 drivers/net/can/at91_can.c        |   32 ---------------------------
 drivers/net/can/dev.c             |   44 +++++++++++++++++++++++++++++++-------
 drivers/net/can/sja1000/sja1000.c |   12 +---------
 drivers/net/can/ti_hecc.c         |   17 +++-----------
 drivers/net/can/usb/ems_usb.c     |   16 +------------
 5 files changed, 44 insertions(+), 77 deletions(-)

Index: net-next-2.6/drivers/net/can/dev.c
===================================================================
--- net-next-2.6.orig/drivers/net/can/dev.c
+++ net-next-2.6/drivers/net/can/dev.c
@@ -291,7 +291,7 @@ void can_put_echo_skb(struct sk_buff *sk
 		skb->sk = srcsk;
 
 		/* make settings for echo to reduce code in irq context */
-		skb->protocol = htons(ETH_P_CAN);
+		skb->protocol = __constant_htons(ETH_P_CAN);
 		skb->pkt_type = PACKET_BROADCAST;
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
 		skb->dev = dev;
@@ -366,17 +366,12 @@ void can_restart(unsigned long data)
 	can_flush_echo_skb(dev);
 
 	/* send restart message upstream */
-	skb = dev_alloc_skb(sizeof(struct can_frame));
+	skb = alloc_can_err_skb(dev, &cf);
 	if (skb == NULL) {
 		err = -ENOMEM;
 		goto restart;
 	}
-	skb->dev = dev;
-	skb->protocol = htons(ETH_P_CAN);
-	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-	memset(cf, 0, sizeof(struct can_frame));
-	cf->can_id = CAN_ERR_FLAG | CAN_ERR_RESTARTED;
-	cf->can_dlc = CAN_ERR_DLC;
+	cf->can_id |= CAN_ERR_RESTARTED;
 
 	netif_rx(skb);
 
@@ -449,6 +444,39 @@ static void can_setup(struct net_device 
 	dev->features = NETIF_F_NO_CSUM;
 }
 
+struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
+{
+	struct sk_buff *skb;
+
+	skb = netdev_alloc_skb(dev, sizeof(struct can_frame));
+	if (unlikely(!skb))
+		return NULL;
+
+	skb->protocol = __constant_htons(ETH_P_CAN);
+	skb->pkt_type = PACKET_BROADCAST;
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
+	memset(*cf, 0, sizeof(struct can_frame));
+
+	return skb;
+}
+EXPORT_SYMBOL_GPL(alloc_can_skb);
+
+struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
+{
+	struct sk_buff *skb;
+
+	skb = alloc_can_skb(dev, cf);
+	if (unlikely(!skb))
+		return NULL;
+
+	(*cf)->can_id = CAN_ERR_FLAG;
+	(*cf)->can_dlc = CAN_ERR_DLC;
+
+	return skb;
+}
+EXPORT_SYMBOL_GPL(alloc_can_err_skb);
+
 /*
  * Allocate and setup space for the CAN network device
  */
Index: net-next-2.6/drivers/net/can/at91_can.c
===================================================================
--- net-next-2.6.orig/drivers/net/can/at91_can.c
+++ net-next-2.6/drivers/net/can/at91_can.c
@@ -221,38 +221,6 @@ static inline void set_mb_mode(const str
 	set_mb_mode_prio(priv, mb, mode, 0);
 }
 
-static struct sk_buff *alloc_can_skb(struct net_device *dev,
-		struct can_frame **cf)
-{
-	struct sk_buff *skb;
-
-	skb = netdev_alloc_skb(dev, sizeof(struct can_frame));
-	if (unlikely(!skb))
-		return NULL;
-
-	skb->protocol = htons(ETH_P_CAN);
-	skb->ip_summed = CHECKSUM_UNNECESSARY;
-	*cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-
-	return skb;
-}
-
-static struct sk_buff *alloc_can_err_skb(struct net_device *dev,
-		struct can_frame **cf)
-{
-	struct sk_buff *skb;
-
-	skb = alloc_can_skb(dev, cf);
-	if (unlikely(!skb))
-		return NULL;
-
-	memset(*cf, 0, sizeof(struct can_frame));
-	(*cf)->can_id = CAN_ERR_FLAG;
-	(*cf)->can_dlc = CAN_ERR_DLC;
-
-	return skb;
-}
-
 /*
  * Swtich transceiver on or off
  */
Index: net-next-2.6/drivers/net/can/sja1000/sja1000.c
===================================================================
--- net-next-2.6.orig/drivers/net/can/sja1000/sja1000.c
+++ net-next-2.6/drivers/net/can/sja1000/sja1000.c
@@ -296,11 +296,9 @@ static void sja1000_rx(struct net_device
 	uint8_t dlc;
 	int i;
 
-	skb = dev_alloc_skb(sizeof(struct can_frame));
+	skb = alloc_can_skb(dev, &cf);
 	if (skb == NULL)
 		return;
-	skb->dev = dev;
-	skb->protocol = htons(ETH_P_CAN);
 
 	fi = priv->read_reg(priv, REG_FI);
 	dlc = fi & 0x0F;
@@ -351,15 +349,9 @@ static int sja1000_err(struct net_device
 	enum can_state state = priv->can.state;
 	uint8_t ecc, alc;
 
-	skb = dev_alloc_skb(sizeof(struct can_frame));
+	skb = alloc_can_err_skb(dev, &cf);
 	if (skb == NULL)
 		return -ENOMEM;
-	skb->dev = dev;
-	skb->protocol = htons(ETH_P_CAN);
-	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-	memset(cf, 0, sizeof(struct can_frame));
-	cf->can_id = CAN_ERR_FLAG;
-	cf->can_dlc = CAN_ERR_DLC;
 
 	if (isrc & IRQ_DOI) {
 		/* data overrun interrupt */
Index: net-next-2.6/drivers/net/can/usb/ems_usb.c
===================================================================
--- net-next-2.6.orig/drivers/net/can/usb/ems_usb.c
+++ net-next-2.6/drivers/net/can/usb/ems_usb.c
@@ -311,14 +311,10 @@ static void ems_usb_rx_can_msg(struct em
 	int i;
 	struct net_device_stats *stats = &dev->netdev->stats;
 
-	skb = netdev_alloc_skb(dev->netdev, sizeof(struct can_frame));
+	skb = alloc_can_skb(dev->netdev, &cf);
 	if (skb == NULL)
 		return;
 
-	skb->protocol = htons(ETH_P_CAN);
-
-	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-
 	cf->can_id = msg->msg.can_msg.id;
 	cf->can_dlc = min_t(u8, msg->msg.can_msg.length, 8);
 
@@ -346,18 +342,10 @@ static void ems_usb_rx_err(struct ems_us
 	struct sk_buff *skb;
 	struct net_device_stats *stats = &dev->netdev->stats;
 
-	skb = netdev_alloc_skb(dev->netdev, sizeof(struct can_frame));
+	skb = alloc_can_err_skb(dev->netdev, &cf);
 	if (skb == NULL)
 		return;
 
-	skb->protocol = htons(ETH_P_CAN);
-
-	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-	memset(cf, 0, sizeof(struct can_frame));
-
-	cf->can_id = CAN_ERR_FLAG;
-	cf->can_dlc = CAN_ERR_DLC;
-
 	if (msg->type == CPC_MSG_TYPE_CAN_STATE) {
 		u8 state = msg->msg.can_state;
 
Index: net-next-2.6/drivers/net/can/ti_hecc.c
===================================================================
--- net-next-2.6.orig/drivers/net/can/ti_hecc.c
+++ net-next-2.6/drivers/net/can/ti_hecc.c
@@ -535,18 +535,15 @@ static int ti_hecc_rx_pkt(struct ti_hecc
 	u32 data, mbx_mask;
 	unsigned long flags;
 
-	skb = netdev_alloc_skb(priv->ndev, sizeof(struct can_frame));
+	skb = alloc_can_skb(priv->ndev, &cf);
 	if (!skb) {
 		if (printk_ratelimit())
 			dev_err(priv->ndev->dev.parent,
-				"ti_hecc_rx_pkt: netdev_alloc_skb() failed\n");
+				"ti_hecc_rx_pkt: alloc_can_skb() failed\n");
 		return -ENOMEM;
 	}
-	skb->protocol = __constant_htons(ETH_P_CAN);
-	skb->ip_summed = CHECKSUM_UNNECESSARY;
 
 	mbx_mask = BIT(mbxno);
-	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
 	data = hecc_read_mbx(priv, mbxno, HECC_CANMID);
 	if (data & HECC_CANMID_IDE)
 		cf->can_id = (data & CAN_EFF_MASK) | CAN_EFF_FLAG;
@@ -656,19 +653,13 @@ static int ti_hecc_error(struct net_devi
 	struct sk_buff *skb;
 
 	/* propogate the error condition to the can stack */
-	skb = netdev_alloc_skb(ndev, sizeof(struct can_frame));
+	skb = alloc_can_err_skb(ndev, &cf);
 	if (!skb) {
 		if (printk_ratelimit())
 			dev_err(priv->ndev->dev.parent,
-				"ti_hecc_error: netdev_alloc_skb() failed\n");
+				"ti_hecc_error: alloc_can_err_skb() failed\n");
 		return -ENOMEM;
 	}
-	skb->protocol = __constant_htons(ETH_P_CAN);
-	skb->ip_summed = CHECKSUM_UNNECESSARY;
-	cf = (struct can_frame *)skb_put(skb, sizeof(struct can_frame));
-	memset(cf, 0, sizeof(struct can_frame));
-	cf->can_id = CAN_ERR_FLAG;
-	cf->can_dlc = CAN_ERR_DLC;
 
 	if (int_status & HECC_CANGIF_WLIF) { /* warning level int */
 		if ((int_status & HECC_CANGIF_BOIF) == 0) {

             reply	other threads:[~2009-10-15  9:22 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-15  9:22 Wolfgang Grandegger [this message]
2009-10-18  6:55 ` [PATCH] can: provide library functions for skb allocation David Miller
2009-10-18 18:46   ` Wolfgang Grandegger

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=4AD6E9CA.3070605@grandegger.com \
    --to=wg-5yr1bzd7o62+xt7jha+gda@public.gmane.org \
    --cc=mkl-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org \
    --cc=netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=socketcan-core-0fE9KPoRgkgATYTw5x5z8w@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.