From 7b6856a0296a8f187bb88ba31fa83a08abba7966 Mon Sep 17 00:00:00 2001 From: Wolfgang Grandegger Date: Tue, 20 Oct 2009 00:08:01 -0700 Subject: can: provide library functions for skb allocation 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 = 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 did not set "pkt_type" or "ip_summed". Also, "__constant_htons()" should not be used for runtime invocations, as pointed out by David Miller. Signed-off-by: Wolfgang Grandegger Signed-off-by: David S. Miller --- drivers/net/can/dev.c | 42 +++++++++++++++++++++++++++++++++++------- 1 file changed, 35 insertions(+), 7 deletions(-) (limited to 'drivers/net/can/dev.c') diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c index 39b99f57c265..c3db111d2ff5 100644 --- a/drivers/net/can/dev.c +++ b/drivers/net/can/dev.c @@ -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) 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 = 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 */ -- cgit v1.2.3