[net-next] macvlan: code refine to check data before using

[Zhang Shengju]

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

Signed-off-by: Zhang Shengju 
---
 drivers/net/macvlan.c | 13 -
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index d2aea96..1ffe77e 100644
--- 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;
-- 
1.8.3.1

Re: [net-next] macvlan: code refine to check data before using

[David Miller]

From: Zhang Shengju 
Date: Wed, 20 Sep 2017 08:12:23 +0800

> This patch checks data first at one place, return if it's null.
> 
> Signed-off-by: Zhang Shengju 

Looks good, applied, thanks.