Jul 20 2014

powerpc/mpic_msgr: Use kcalloc and correct the argument to sizeof 

Author: Himangi Saraogi <himangi774@gmail.com>

mpic_msgrs has type struct mpic_msgr **, not struct mpic_msgr *, so the
elements of the array should have pointer type, not structure type.
The advantage of kcalloc is, that will prevent integer overflows which
could result from the multiplication of number of elements and size and
it is also a bit nicer to read.

The Coccinelle semantic patch that makes the first change is as follows:

// 
@disable sizeof_type_expr@
type T;
T **x;
@@

  x =
  <+...sizeof(
- T
+ *x
  )...+>
// 

Signed-off-by: Himangi Saraogi 
Acked-by: Julia Lawall 
Signed-off-by: Scott Wood 

---
 arch/powerpc/sysdev/mpic_msgr.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
 
diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c
index 2c9b52a..7bdf3cc 100644
--- a/arch/powerpc/sysdev/mpic_msgr.c
+++ b/arch/powerpc/sysdev/mpic_msgr.c
@@ -184,7 +184,7 @@ static int mpic_msgr_probe(struct platform_device *dev)
 		dev_info(&dev->dev, "Found %d message registers\n",
 				mpic_msgr_count);
 
-		mpic_msgrs = kzalloc(sizeof(struct mpic_msgr) * mpic_msgr_count,
+		mpic_msgrs = kcalloc(mpic_msgr_count, sizeof(*mpic_msgrs),
 							 GFP_KERNEL);
 		if (!mpic_msgrs) {
 			dev_err(&dev->dev,

qlambert