arch/mn10300/mm: eliminate NULL dereference

Author: Julia Lawall <julia@diku.dk>

dev_name always dereferences its argument, so it should not be called if
the argument is NULL.  The function indeed later tests the argument for
being NULL.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

  // 
  @@
  expression dev,E;
  @@

  *dev_name(dev)
  ... when != dev = E
  (
  *dev == NULL
  |
  *dev != NULL
  )
  // 

Signed-off-by: Julia Lawall 
Signed-off-by: David Howells 
Signed-off-by: Linus Torvalds

---
 arch/mn10300/mm/dma-alloc.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
 
diff --git a/arch/mn10300/mm/dma-alloc.c b/arch/mn10300/mm/dma-alloc.c
index 4e34880..159acb0 100644
--- a/arch/mn10300/mm/dma-alloc.c
+++ b/arch/mn10300/mm/dma-alloc.c
@@ -25,7 +25,8 @@ void *dma_alloc_coherent(struct device *dev, size_t size,
 	unsigned long addr;
 	void *ret;
 
-	printk("dma_alloc_coherent(%s,%zu,,%x)\n", dev_name(dev), size, gfp);
+	pr_debug("dma_alloc_coherent(%s,%zu,%x)\n",
+		 dev ? dev_name(dev) : "?", size, gfp);
 
 	if (0xbe000000 - pci_sram_allocated >= size) {
 		size = (size + 255) & ~255;

arch/mn10300/mm: eliminate NULL dereference

qlambert

Archives

Posts by Subject