1 files changed, 48 insertions, 51 deletions

diff --git a/include/linux/can/skb.h b/include/linux/can/skb.h
index d311bc369a39..1abc25a8d144 100644
--- a/include/linux/can/skb.h
+++ b/include/linux/can/skb.h
@@ -20,16 +20,22 @@ void can_flush_echo_skb(struct net_device *dev);
 int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 		     unsigned int idx, unsigned int frame_len);
 struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
-				   u8 *len_ptr, unsigned int *frame_len_ptr);
-unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx,
-			      unsigned int *frame_len_ptr);
+				   unsigned int *len_ptr,
+				   unsigned int *frame_len_ptr);
+unsigned int __must_check can_get_echo_skb(struct net_device *dev,
+					   unsigned int idx,
+					   unsigned int *frame_len_ptr);
 void can_free_echo_skb(struct net_device *dev, unsigned int idx,
 		       unsigned int *frame_len_ptr);
 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
 struct sk_buff *alloc_canfd_skb(struct net_device *dev,
 				struct canfd_frame **cfd);
+struct sk_buff *alloc_canxl_skb(struct net_device *dev,
+				struct canxl_frame **cxl,
+				unsigned int data_len);
 struct sk_buff *alloc_can_err_skb(struct net_device *dev,
 				  struct can_frame **cf);
+bool can_dropped_invalid_skb(struct net_device *dev, struct sk_buff *skb);
 
 /*
  * The struct can_skb_priv is used to transport additional information along
@@ -95,68 +101,59 @@ static inline struct sk_buff *can_create_echo_skb(struct sk_buff *skb)
 	return nskb;
 }
 
-/* Check for outgoing skbs that have not been created by the CAN subsystem */
-static inline bool can_skb_headroom_valid(struct net_device *dev,
-					  struct sk_buff *skb)
+static inline bool can_is_can_skb(const struct sk_buff *skb)
 {
-	/* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */
-	if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv)))
-		return false;
+	struct can_frame *cf = (struct can_frame *)skb->data;
 
-	/* af_packet does not apply CAN skb specific settings */
-	if (skb->ip_summed == CHECKSUM_NONE) {
-		/* init headroom */
-		can_skb_prv(skb)->ifindex = dev->ifindex;
-		can_skb_prv(skb)->skbcnt = 0;
+	/* the CAN specific type of skb is identified by its data length */
+	return (skb->len == CAN_MTU && cf->len <= CAN_MAX_DLEN);
+}
 
-		skb->ip_summed = CHECKSUM_UNNECESSARY;
+static inline bool can_is_canfd_skb(const struct sk_buff *skb)
+{
+	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
 
-		/* perform proper loopback on capable devices */
-		if (dev->flags & IFF_ECHO)
-			skb->pkt_type = PACKET_LOOPBACK;
-		else
-			skb->pkt_type = PACKET_HOST;
+	/* the CAN specific type of skb is identified by its data length */
+	return (skb->len == CANFD_MTU && cfd->len <= CANFD_MAX_DLEN);
+}
 
-		skb_reset_mac_header(skb);
-		skb_reset_network_header(skb);
-		skb_reset_transport_header(skb);
-	}
+static inline bool can_is_canxl_skb(const struct sk_buff *skb)
+{
+	const struct canxl_frame *cxl = (struct canxl_frame *)skb->data;
 
-	return true;
+	if (skb->len < CANXL_HDR_SIZE + CANXL_MIN_DLEN || skb->len > CANXL_MTU)
+		return false;
+
+	/* this also checks valid CAN XL data length boundaries */
+	if (skb->len != CANXL_HDR_SIZE + cxl->len)
+		return false;
+
+	return cxl->flags & CANXL_XLF;
 }
 
-/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
-static inline bool can_dropped_invalid_skb(struct net_device *dev,
-					  struct sk_buff *skb)
+/* get length element value from can[|fd|xl]_frame structure */
+static inline unsigned int can_skb_get_len_val(struct sk_buff *skb)
 {
+	const struct canxl_frame *cxl = (struct canxl_frame *)skb->data;
 	const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
 
-	if (skb->protocol == htons(ETH_P_CAN)) {
-		if (unlikely(skb->len != CAN_MTU ||
-			     cfd->len > CAN_MAX_DLEN))
-			goto inval_skb;
-	} else if (skb->protocol == htons(ETH_P_CANFD)) {
-		if (unlikely(skb->len != CANFD_MTU ||
-			     cfd->len > CANFD_MAX_DLEN))
-			goto inval_skb;
-	} else
-		goto inval_skb;
-
-	if (!can_skb_headroom_valid(dev, skb))
-		goto inval_skb;
-
-	return false;
-
-inval_skb:
-	kfree_skb(skb);
-	dev->stats.tx_dropped++;
-	return true;
+	if (can_is_canxl_skb(skb))
+		return cxl->len;
+
+	return cfd->len;
 }
 
-static inline bool can_is_canfd_skb(const struct sk_buff *skb)
+/* get needed data length inside CAN frame for all frame types (RTR aware) */
+static inline unsigned int can_skb_get_data_len(struct sk_buff *skb)
 {
-	/* the CAN specific type of skb is identified by its data length */
-	return skb->len == CANFD_MTU;
+	unsigned int len = can_skb_get_len_val(skb);
+	const struct can_frame *cf = (struct can_frame *)skb->data;
+
+	/* RTR frames have an actual length of zero */
+	if (can_is_can_skb(skb) && cf->can_id & CAN_RTR_FLAG)
+		return 0;
+
+	return len;
 }
 
 #endif /* !_CAN_SKB_H */