macvlan: code refine to check data before using

This patch checks data first at one place, return if it's null.

Signed-off-by: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index d2aea96..1ffe77e 100644 (file)
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -1231,11 +1231,14 @@ static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[],
                        return -EADDRNOTAVAIL;
        }
 
-       if (data && data[IFLA_MACVLAN_FLAGS] &&
+       if (!data)
+               return 0;
+
+       if (data[IFLA_MACVLAN_FLAGS] &&
            nla_get_u16(data[IFLA_MACVLAN_FLAGS]) & ~MACVLAN_FLAG_NOPROMISC)
                return -EINVAL;
 
-       if (data && data[IFLA_MACVLAN_MODE]) {
+       if (data[IFLA_MACVLAN_MODE]) {
                switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
                case MACVLAN_MODE_PRIVATE:
                case MACVLAN_MODE_VEPA:
@@ -1248,7 +1251,7 @@ static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[],
                }
        }
 
-       if (data && data[IFLA_MACVLAN_MACADDR_MODE]) {
+       if (data[IFLA_MACVLAN_MACADDR_MODE]) {
                switch (nla_get_u32(data[IFLA_MACVLAN_MACADDR_MODE])) {
                case MACVLAN_MACADDR_ADD:
                case MACVLAN_MACADDR_DEL:
@@ -1260,7 +1263,7 @@ static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[],
                }
        }
 
-       if (data && data[IFLA_MACVLAN_MACADDR]) {
+       if (data[IFLA_MACVLAN_MACADDR]) {
                if (nla_len(data[IFLA_MACVLAN_MACADDR]) != ETH_ALEN)
                        return -EINVAL;
 
@@ -1268,7 +1271,7 @@ static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[],
                        return -EADDRNOTAVAIL;
        }
 
-       if (data && data[IFLA_MACVLAN_MACADDR_COUNT])
+       if (data[IFLA_MACVLAN_MACADDR_COUNT])
                return -EINVAL;
 
        return 0;