From: Nikolay Aleksandrov <razor@blackwall.org>
Date: Wed, 13 Apr 2022 10:51:52 +0000 (+0300)
Subject: net: rtnetlink: add helper to extract msg type's kind
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2e9ea3e30f696fd438319c07836422bb0bbb4608;p=linux.git

net: rtnetlink: add helper to extract msg type's kind

Add a helper which extracts the msg type's kind using the kind mask (0x3).

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 78712b51f3dad..c51c5ff7f7e2a 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -19,6 +19,12 @@ enum rtnl_kinds {
 	RTNL_KIND_GET,
 	RTNL_KIND_SET
 };
+#define RTNL_KIND_MASK 0x3
+
+static inline enum rtnl_kinds rtnl_msgtype_kind(int msgtype)
+{
+	return msgtype & RTNL_KIND_MASK;
+}
 
 void rtnl_register(int protocol, int msgtype,
 		   rtnl_doit_func, rtnl_dumpit_func, unsigned int flags);
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 2c36c9dc9b627..beda4a7da0625 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -5947,7 +5947,7 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return 0;
 
 	family = ((struct rtgenmsg *)nlmsg_data(nlh))->rtgen_family;
-	kind = type&3;
+	kind = rtnl_msgtype_kind(type);
 
 	if (kind != RTNL_KIND_GET && !netlink_net_capable(skb, CAP_NET_ADMIN))
 		return -EPERM;