[PATCH net-next v4 02/12] net: rtnetlink: add helper to extract msg type's kind

Nikolay Aleksandrov
2022-04-13T10:52:29Z

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

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
---
v4: new patch

include/net/rtnetlink.h | 6 ++++++
net/core/rtnetlink.c | 2 +-
2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 78712b51f3da..c51c5ff7f7e2 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 2c36c9dc9b62..beda4a7da062 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;
--
2.35.1