How to apply a patch for Linux source code

For example, I need to apply this patch for my Linux source code: http://git.kernel.org/cgit/linux/kernel/git/davem/net.git/diff/?id=fe82b3300ec9c0dc4ba871f9a58b265aadf4e186

First, I copy this paragraph to a file in local directory: /usr/src/linux-4.3/patch.file.

"

diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c
index 67591ae..64afd3d 100644
--- a/net/mpls/mpls_iptunnel.c
+++ b/net/mpls/mpls_iptunnel.c

@@ -54,10 +54,10 @@ int mpls_output(struct net *net, struct sock *sk, struct sk_buff *skb)

unsigned int ttl;

 

/* Obtain the ttl */

- if (skb->protocol == htons(ETH_P_IP)) {

+ if (dst->ops->family == AF_INET) {

ttl = ip_hdr(skb)->ttl;

rt = (struct rtable *)dst;

- } else if (skb->protocol == htons(ETH_P_IPV6)) {

+ } else if (dst->ops->family == AF_INET6) {

ttl = ipv6_hdr(skb)->hop_limit;

rt6 = (struct rt6_info *)dst;

} else {

"

and then use this command to do the patch:

# patch < patch.file

and then I got the warning info:

"

can't find file to patch at input line 5
Perhaps you should have used the -p or --strip option?
The text leading up to this was:
--------------------------
|diff --git a/net/mpls/mpls_iptunnel.c b/net/mpls/mpls_iptunnel.c
|index 67591ae..64afd3d 100644
|--- a/net/mpls/mpls_iptunnel.c
|+++ b/net/mpls/mpls_iptunnel.c
--------------------------
File to patch:

"

I ignore the warning and input the file name: net/mpls/mpls_iptunnel.c

And then the patch is applied.