To prevent the CAN drivers to operate on invalid socketbuffers the skbs are now checked and silently dropped at the xmit-function consistently.
Also the netdev stats are consistently using the CAN data length code (dlc) for [rx|tx]_bytes now. Signed-off-by: Oliver Hartkopp <[email protected]> --- diff --git a/drivers/net/can/at91_can.c b/drivers/net/can/at91_can.c index 166cc7e..f728749 100644 --- a/drivers/net/can/at91_can.c +++ b/drivers/net/can/at91_can.c @@ -342,6 +342,9 @@ static netdev_tx_t at91_start_xmit(struct sk_buff *skb, struct net_device *dev) unsigned int mb, prio; u32 reg_mid, reg_mcr; + if (can_dropped_invalid_skb(dev, skb)) + return NETDEV_TX_OK; + mb = get_tx_next_mb(priv); prio = get_tx_next_prio(priv); diff --git a/drivers/net/can/bfin_can.c b/drivers/net/can/bfin_can.c index 0ec1524..7e1926e 100644 --- a/drivers/net/can/bfin_can.c +++ b/drivers/net/can/bfin_can.c @@ -318,6 +318,9 @@ static int bfin_can_start_xmit(struct sk_buff *skb, struct net_device *dev) u16 val; int i; + if (can_dropped_invalid_skb(dev, skb)) + return NETDEV_TX_OK; + netif_stop_queue(dev); /* fill id */ diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c index 1a72ca0..afa2fa4 100644 --- a/drivers/net/can/mcp251x.c +++ b/drivers/net/can/mcp251x.c @@ -494,12 +494,8 @@ static netdev_tx_t mcp251x_hard_start_xmit(struct sk_buff *skb, return NETDEV_TX_BUSY; } - if (skb->len != sizeof(struct can_frame)) { - dev_err(&spi->dev, "dropping packet - bad length\n"); - dev_kfree_skb(skb); - net->stats.tx_dropped++; + if (can_dropped_invalid_skb(net, skb)) return NETDEV_TX_OK; - } netif_stop_queue(net); priv->tx_skb = skb; diff --git a/drivers/net/can/mscan/mscan.c b/drivers/net/can/mscan/mscan.c index 500d189..40827c1 100644 --- a/drivers/net/can/mscan/mscan.c +++ b/drivers/net/can/mscan/mscan.c @@ -204,11 +204,8 @@ static netdev_tx_t mscan_start_xmit(struct sk_buff *skb, struct net_device *dev) int i, rtr, buf_id; u32 can_id; - if (skb->len != sizeof(*frame) || frame->can_dlc > 8) { - kfree_skb(skb); - dev->stats.tx_dropped++; + if (can_dropped_invalid_skb(dev, skb)) return NETDEV_TX_OK; - } out_8(®s->cantier, 0); diff --git a/drivers/net/can/sja1000/sja1000.c b/drivers/net/can/sja1000/sja1000.c index 542a4f7..345304d 100644 --- a/drivers/net/can/sja1000/sja1000.c +++ b/drivers/net/can/sja1000/sja1000.c @@ -249,6 +249,9 @@ static netdev_tx_t sja1000_start_xmit(struct sk_buff *skb, uint8_t dreg; int i; + if (can_dropped_invalid_skb(dev, skb)) + return NETDEV_TX_OK; + netif_stop_queue(dev); fi = dlc = cf->can_dlc; diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c index 5c993c2..7d370e3 100644 --- a/drivers/net/can/ti_hecc.c +++ b/drivers/net/can/ti_hecc.c @@ -477,6 +477,9 @@ static netdev_tx_t ti_hecc_xmit(struct sk_buff *skb, struct net_device *ndev) u32 mbxno, mbx_mask, data; unsigned long flags; + if (can_dropped_invalid_skb(ndev, skb)) + return NETDEV_TX_OK; + mbxno = get_tx_head_mb(priv); mbx_mask = BIT(mbxno); spin_lock_irqsave(&priv->mbx_lock, flags); @@ -491,7 +494,6 @@ static netdev_tx_t ti_hecc_xmit(struct sk_buff *skb, struct net_device *ndev) spin_unlock_irqrestore(&priv->mbx_lock, flags); /* Prepare mailbox for transmission */ - data = min_t(u8, cf->can_dlc, 8); if (cf->can_id & CAN_RTR_FLAG) /* Remote transmission request */ data |= HECC_CANMCF_RTR; data |= get_tx_head_prio(priv) << 8; diff --git a/drivers/net/can/usb/ems_usb.c b/drivers/net/can/usb/ems_usb.c index efbb05c..ddb17e2 100644 --- a/drivers/net/can/usb/ems_usb.c +++ b/drivers/net/can/usb/ems_usb.c @@ -767,6 +767,9 @@ static netdev_tx_t ems_usb_start_xmit(struct sk_buff *skb, struct net_device *ne size_t size = CPC_HEADER_SIZE + CPC_MSG_HEADER_LEN + sizeof(struct cpc_can_msg); + if (can_dropped_invalid_skb(netdev, skb)) + return NETDEV_TX_OK; + /* create a URB, and a buffer for it, and copy the data to the URB */ urb = usb_alloc_urb(0, GFP_ATOMIC); if (!urb) { diff --git a/drivers/net/can/vcan.c b/drivers/net/can/vcan.c index 80ac563..d124d83 100644 --- a/drivers/net/can/vcan.c +++ b/drivers/net/can/vcan.c @@ -47,6 +47,7 @@ #include <linux/if_arp.h> #include <linux/if_ether.h> #include <linux/can.h> +#include <linux/can/dev.h> #include <net/rtnetlink.h> static __initdata const char banner[] = @@ -70,10 +71,11 @@ MODULE_PARM_DESC(echo, "Echo sent frames (for testing). Default: 0 (Off)"); static void vcan_rx(struct sk_buff *skb, struct net_device *dev) { + struct can_frame *cf = (struct can_frame *)skb->data; struct net_device_stats *stats = &dev->stats; stats->rx_packets++; - stats->rx_bytes += skb->len; + stats->rx_bytes += cf->can_dlc; skb->protocol = htons(ETH_P_CAN); skb->pkt_type = PACKET_BROADCAST; @@ -85,11 +87,15 @@ static void vcan_rx(struct sk_buff *skb, struct net_device *dev) static netdev_tx_t vcan_tx(struct sk_buff *skb, struct net_device *dev) { + struct can_frame *cf = (struct can_frame *)skb->data; struct net_device_stats *stats = &dev->stats; int loop; + if (can_dropped_invalid_skb(dev, skb)) + return NETDEV_TX_OK; + stats->tx_packets++; - stats->tx_bytes += skb->len; + stats->tx_bytes += cf->can_dlc; /* set flag whether this packet has to be looped back */ loop = skb->pkt_type == PACKET_LOOPBACK; @@ -103,7 +109,7 @@ static netdev_tx_t vcan_tx(struct sk_buff *skb, struct net_device *dev) * CAN core already did the echo for us */ stats->rx_packets++; - stats->rx_bytes += skb->len; + stats->rx_bytes += cf->can_dlc; } kfree_skb(skb); return NETDEV_TX_OK; diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 3db7767..7e7c98a 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -60,6 +60,21 @@ struct can_priv { */ #define get_can_dlc(i) (min_t(__u8, (i), 8)) +/* Drop a given socketbuffer if it does not contain a valid CAN frame. */ +static inline int can_dropped_invalid_skb(struct net_device *dev, + struct sk_buff *skb) +{ + const struct can_frame *cf = (struct can_frame *)skb->data; + + if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) { + kfree_skb(skb); + dev->stats.tx_dropped++; + return 1; + } + + return 0; +} + struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); void free_candev(struct net_device *dev); _______________________________________________ Socketcan-core mailing list [email protected] https://lists.berlios.de/mailman/listinfo/socketcan-core
