Jan 09 2009

net/bridge/netfilter: move a dereference below a NULL test 

Author: Julia Lawall <julia@diku.dk>

In each case, if the NULL test is necessary, then the dereference should be
moved below the NULL test.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// 
@@
type T;
expression E;
identifier i,fld;
statement S;
@@

- T i = E->fld;
+ T i;
  ... when != E
      when != i
  if (E == NULL) S
+ i = E->fld;
// 

Signed-off-by: Julia Lawall 
Signed-off-by: Andrew Morton 
Signed-off-by: David S. Miller 

---
 net/bridge/netfilter/ebtables.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
 
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index fa108c4..8a8743d 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -85,12 +85,13 @@ static inline int ebt_do_match (struct ebt_entry_match *m,
 static inline int ebt_dev_check(char *entry, const struct net_device *device)
 {
 	int i = 0;
-	const char *devname = device->name;
+	const char *devname;
 
 	if (*entry == '\0')
 		return 0;
 	if (!device)
 		return 1;
+	devname = device->name;
 	/* 1 is the wildcard token */
 	while (entry[i] != '\0' && entry[i] != 1 && entry[i] == devname[i])
 		i++;

qlambert