--- zzzz-none-000/linux-3.10.107/net/can/af_can.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/net/can/af_can.c	2021-02-04 17:41:59.000000000 +0000
@@ -64,9 +64,6 @@
 
 #include "af_can.h"
 
-static __initconst const char banner[] = KERN_INFO
-	"can: controller area network core (" CAN_VERSION_STRING ")\n";
-
 MODULE_DESCRIPTION("Controller Area Network PF_CAN core");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
@@ -92,6 +89,8 @@
 struct s_stats    can_stats;       /* packet statistics */
 struct s_pstats   can_pstats;      /* receive list statistics */
 
+static atomic_t skbcounter = ATOMIC_INIT(0);
+
 /*
  * af_can socket functions
  */
@@ -182,7 +181,7 @@
 
 	sock->ops = cp->ops;
 
-	sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot);
+	sk = sk_alloc(net, PF_CAN, GFP_KERNEL, cp->prot, kern);
 	if (!sk) {
 		err = -ENOMEM;
 		goto errout;
@@ -341,6 +340,29 @@
 }
 
 /**
+ * effhash - hash function for 29 bit CAN identifier reduction
+ * @can_id: 29 bit CAN identifier
+ *
+ * Description:
+ *  To reduce the linear traversal in one linked list of _single_ EFF CAN
+ *  frame subscriptions the 29 bit identifier is mapped to 10 bits.
+ *  (see CAN_EFF_RCV_HASH_BITS definition)
+ *
+ * Return:
+ *  Hash value from 0x000 - 0x3FF ( enforced by CAN_EFF_RCV_HASH_BITS mask )
+ */
+static unsigned int effhash(canid_t can_id)
+{
+	unsigned int hash;
+
+	hash = can_id;
+	hash ^= can_id >> CAN_EFF_RCV_HASH_BITS;
+	hash ^= can_id >> (2 * CAN_EFF_RCV_HASH_BITS);
+
+	return hash & ((1 << CAN_EFF_RCV_HASH_BITS) - 1);
+}
+
+/**
  * find_rcv_list - determine optimal filterlist inside device filter struct
  * @can_id: pointer to CAN identifier of a given can_filter
  * @mask: pointer to CAN mask of a given can_filter
@@ -403,10 +425,8 @@
 	    !(*can_id & CAN_RTR_FLAG)) {
 
 		if (*can_id & CAN_EFF_FLAG) {
-			if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS)) {
-				/* RFC: a future use-case for hash-tables? */
-				return &d->rx[RX_EFF];
-			}
+			if (*mask == (CAN_EFF_MASK | CAN_EFF_RTR_FLAGS))
+				return &d->rx_eff[effhash(*can_id)];
 		} else {
 			if (*mask == (CAN_SFF_MASK | CAN_EFF_RTR_FLAGS))
 				return &d->rx_sff[*can_id];
@@ -424,7 +444,7 @@
  * @mask: CAN mask (see description)
  * @func: callback function on filter match
  * @data: returned parameter for callback function
- * @ident: string for calling module indentification
+ * @ident: string for calling module identification
  * @sk: socket pointer (might be NULL)
  *
  * Description:
@@ -511,7 +531,7 @@
 
 /**
  * can_rx_unregister - unsubscribe CAN frames from a specific interface
- * @dev: pointer to netdevice (NULL => unsubcribe from 'all' CAN devices list)
+ * @dev: pointer to netdevice (NULL => unsubscribe from 'all' CAN devices list)
  * @can_id: CAN identifier
  * @mask: CAN mask
  * @func: callback function on filter match
@@ -643,7 +663,7 @@
 		return matches;
 
 	if (can_id & CAN_EFF_FLAG) {
-		hlist_for_each_entry_rcu(r, &d->rx[RX_EFF], list) {
+		hlist_for_each_entry_rcu(r, &d->rx_eff[effhash(can_id)], list) {
 			if (r->can_id == can_id) {
 				deliver(skb, r);
 				matches++;
@@ -669,6 +689,10 @@
 	can_stats.rx_frames++;
 	can_stats.rx_frames_delta++;
 
+	/* create non-zero unique skb identifier together with *skb */
+	while (!(can_skb_prv(skb)->skbcnt))
+		can_skb_prv(skb)->skbcnt = atomic_inc_return(&skbcounter);
+
 	rcu_read_lock();
 
 	/* deliver the packet to sockets listening on all devices */
@@ -806,9 +830,9 @@
  * af_can notifier to create/remove CAN netdevice specific structs
  */
 static int can_notifier(struct notifier_block *nb, unsigned long msg,
-			void *data)
+			void *ptr)
 {
-	struct net_device *dev = (struct net_device *)data;
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct dev_rcv_lists *d;
 
 	if (!net_eq(dev_net(dev), &init_net))
@@ -886,7 +910,7 @@
 		     offsetof(struct can_frame, data) !=
 		     offsetof(struct canfd_frame, data));
 
-	printk(banner);
+	pr_info("can: controller area network core (" CAN_VERSION_STRING ")\n");
 
 	memset(&can_rx_alldev_list, 0, sizeof(can_rx_alldev_list));