Introduce ipv6 ns/nd checking helper, using skb_header_pointer()
instead of pskb_network_may_pull() on tx path.

alb_determine_nd introduced from commit 0da8aa00bfcfe

Cc: Jay Vosburgh <jv@jvosburgh.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Tonghao Zhang <tonghao@bamaicloud.com>
Signed-off-by: Zengbing Tu <tuzengbing@didiglobal.com>
---
 drivers/net/bonding/bond_alb.c  | 32 +++++++-------------------------
 drivers/net/bonding/bond_main.c | 17 ++---------------
 include/net/bonding.h           | 19 +++++++++++++++++++
 3 files changed, 28 insertions(+), 40 deletions(-)

diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
index 2d37b07c8215..8e5b9ce52077 100644
--- a/drivers/net/bonding/bond_alb.c
+++ b/drivers/net/bonding/bond_alb.c
@@ -19,7 +19,6 @@
 #include <linux/in.h>
 #include <net/arp.h>
 #include <net/ipv6.h>
-#include <net/ndisc.h>
 #include <asm/byteorder.h>
 #include <net/bonding.h>
 #include <net/bond_alb.h>
@@ -1280,27 +1279,6 @@ static int alb_set_mac_address(struct bonding *bond, void *addr)
 	return res;
 }
 
-/* determine if the packet is NA or NS */
-static bool alb_determine_nd(struct sk_buff *skb, struct bonding *bond)
-{
-	struct ipv6hdr *ip6hdr;
-	struct icmp6hdr *hdr;
-
-	if (!pskb_network_may_pull(skb, sizeof(*ip6hdr)))
-		return true;
-
-	ip6hdr = ipv6_hdr(skb);
-	if (ip6hdr->nexthdr != IPPROTO_ICMPV6)
-		return false;
-
-	if (!pskb_network_may_pull(skb, sizeof(*ip6hdr) + sizeof(*hdr)))
-		return true;
-
-	hdr = icmp6_hdr(skb);
-	return hdr->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT ||
-		hdr->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION;
-}
-
 /************************ exported alb functions ************************/
 
 int bond_alb_initialize(struct bonding *bond, int rlb_enabled)
@@ -1381,7 +1359,7 @@ struct slave *bond_xmit_tlb_slave_get(struct bonding *bond,
 	if (!is_multicast_ether_addr(eth_data->h_dest)) {
 		switch (skb->protocol) {
 		case htons(ETH_P_IPV6):
-			if (alb_determine_nd(skb, bond))
+			if (bond_is_icmpv6_nd(skb))
 				break;
 			fallthrough;
 		case htons(ETH_P_IP):
@@ -1467,16 +1445,20 @@ struct slave *bond_xmit_alb_slave_get(struct bonding *bond,
 			break;
 		}
 
-		if (alb_determine_nd(skb, bond)) {
+		if (bond_is_icmpv6_nd(skb)) {
 			do_tx_balance = false;
 			break;
 		}
 
-		/* The IPv6 header is pulled by alb_determine_nd */
 		/* Additionally, DAD probes should not be tx-balanced as that
 		 * will lead to false positives for duplicate addresses and
 		 * prevent address configuration from working.
 		 */
+		if (!pskb_network_may_pull(skb, sizeof(*ip6hdr))) {
+			do_tx_balance = false;
+			break;
+		}
+
 		ip6hdr = ipv6_hdr(skb);
 		if (ipv6_addr_any(&ip6hdr->saddr)) {
 			do_tx_balance = false;
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 17c7542be6a5..a8034a561011 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -5338,10 +5338,6 @@ static bool bond_should_broadcast_neighbor(struct sk_buff *skb,
 					   struct net_device *dev)
 {
 	struct bonding *bond = netdev_priv(dev);
-	struct {
-		struct ipv6hdr ip6;
-		struct icmp6hdr icmp6;
-	} *combined, _combined;
 
 	if (!static_branch_unlikely(&bond_bcast_neigh_enabled))
 		return false;
@@ -5349,19 +5345,10 @@ static bool bond_should_broadcast_neighbor(struct sk_buff *skb,
 	if (!bond->params.broadcast_neighbor)
 		return false;
 
-	if (skb->protocol == htons(ETH_P_ARP))
+	if (skb->protocol == htons(ETH_P_ARP) ||
+	    (skb->protocol == htons(ETH_P_IPV6) && bond_is_icmpv6_nd(skb)))
 		return true;
 
-	if (skb->protocol == htons(ETH_P_IPV6)) {
-		combined = skb_header_pointer(skb, skb_mac_header_len(skb),
-					      sizeof(_combined),
-					      &_combined);
-		if (combined && combined->ip6.nexthdr == NEXTHDR_ICMP &&
-		    (combined->icmp6.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
-		     combined->icmp6.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT))
-			return true;
-	}
-
 	return false;
 }
 
diff --git a/include/net/bonding.h b/include/net/bonding.h
index e06f0d63b2c1..32d9fcca858c 100644
--- a/include/net/bonding.h
+++ b/include/net/bonding.h
@@ -29,6 +29,7 @@
 #include <net/bond_options.h>
 #include <net/ipv6.h>
 #include <net/addrconf.h>
+#include <net/ndisc.h>
 
 #define BOND_MAX_ARP_TARGETS	16
 #define BOND_MAX_NS_TARGETS	BOND_MAX_ARP_TARGETS
@@ -814,4 +815,22 @@ static inline netdev_tx_t bond_tx_drop(struct net_device *dev, struct sk_buff *s
 	return NET_XMIT_DROP;
 }
 
+static inline bool bond_is_icmpv6_nd(struct sk_buff *skb)
+{
+	struct {
+		struct ipv6hdr ip6;
+		struct icmp6hdr icmp6;
+	} *combined, _combined;
+
+	combined = skb_header_pointer(skb, skb_mac_header_len(skb),
+				      sizeof(_combined),
+				      &_combined);
+	if (combined && combined->ip6.nexthdr == NEXTHDR_ICMP &&
+	    (combined->icmp6.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
+	     combined->icmp6.icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT))
+		return true;
+
+	return false;
+}
+
 #endif /* _NET_BONDING_H */
-- 
2.34.1