[PATCH] net: ipv4: add code comment for clarification

["Gustavo A. R. Silva" <garsilva@embeddedor.com>]

Add code comment to make it clear that the position of the arguments
req->id.idiag_dport and req->id.idiag_sport is a locked in behavior
and it should not be changed.

Addresses-Coverity-ID: 1357474
Cc: David Miller <davem@davemloft.net>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
---
 net/ipv4/inet_diag.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 3828b3a..841800b 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -389,6 +389,12 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
 				  nlmsg_flags, unlh, net_admin);
 }
 
+/*
+ * Ignore the position of the arguments req->id.idiag_dport and
+ * req->id.idiag_sport in both calls to inet_lookup() and inet6_lookup()
+ * functions, once this is a locked in behavior exposed to user space.
+ * Changing this will break things for people.
+ */
 struct sock *inet_diag_find_one_icsk(struct net *net,
 				     struct inet_hashinfo *hashinfo,
 				     const struct inet_diag_req_v2 *req)
-- 
2.5.0