diff --git a/drivers/net/ppp/pppoe.c b/drivers/net/ppp/pppoe.c
index 583d50f80b24..02327e6c4819 100644
--- a/drivers/net/ppp/pppoe.c
+++ b/drivers/net/ppp/pppoe.c
@@ -442,6 +442,7 @@ static int pppoe_rcv(struct sk_buff *skb, struct net_device *dev,
 	if (pskb_trim_rcsum(skb, len))
 		goto drop;
 
+	ph = pppoe_hdr(skb);
 	pn = pppoe_pernet(dev_net(dev));
 
 	/* Note that get_item does a sock_hold(), so sk_pppox(po)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index a490dd718654..6d39d81d3c38 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2798,6 +2798,7 @@ static inline unsigned char *skb_push_rcsum(struct sk_buff *skb,
  *
  *	This is exactly the same as pskb_trim except that it ensures the
  *	checksum of received packets are still valid after the operation.
+ *	It can change skb pointers.
  */
 
 static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
index d61f56efc8dc..69dfd212e50d 100644
--- a/net/bridge/br_netfilter_ipv6.c
+++ b/net/bridge/br_netfilter_ipv6.c
@@ -131,6 +131,7 @@ int br_validate_ipv6(struct net *net, struct sk_buff *skb)
 					 IPSTATS_MIB_INDISCARDS);
 			goto drop;
 		}
+		hdr = ipv6_hdr(skb);
 	}
 	if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb))
 		goto drop;
diff --git a/net/bridge/netfilter/nft_reject_bridge.c b/net/bridge/netfilter/nft_reject_bridge.c
index fdba3d9fbff3..6e48aa69fa24 100644
--- a/net/bridge/netfilter/nft_reject_bridge.c
+++ b/net/bridge/netfilter/nft_reject_bridge.c
@@ -192,6 +192,7 @@ static bool reject6_br_csum_ok(struct sk_buff *skb, int hook)
 	    pskb_trim_rcsum(skb, ntohs(ip6h->payload_len) + sizeof(*ip6h)))
 		return false;
 
+	ip6h = ipv6_hdr(skb);
 	thoff = ipv6_skip_exthdr(skb, ((u8*)(ip6h+1) - skb->data), &proto, &fo);
 	if (thoff < 0 || thoff >= skb->len || (fo & htons(~0x7)) != 0)
 		return false;
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index b1209b63381f..eb1834f2682f 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -444,6 +444,7 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
 		goto drop;
 	}
 
+	iph = ip_hdr(skb);
 	skb->transport_header = skb->network_header + iph->ihl*4;
 
 	/* Remove any debris in the socket control block */