powerpc/5200: efika.c: Add of_node_put to avoid memory leak

Author: Julia Lawall <julia@diku.dk>

This function is implemented as though the function of_get_next_child does
not increment the reference count of its result, but actually it does.
Thus the patch adds of_node_put in error handling code and drops a call to
of_node_get.

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

// 
@r exists@
local idexpression x;
expression E1;
position p1,p2;
@@

x@p1 = of_get_next_child(...);
... when != x = E1
of_node_get@p2(x)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

cocci.print_main("call",p1)
cocci.print_secs("get",p2)
// 

Signed-off-by: Julia Lawall 
Signed-off-by: Grant Likely

---
 arch/powerpc/platforms/52xx/efika.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)
 
diff --git a/arch/powerpc/platforms/52xx/efika.c b/arch/powerpc/platforms/52xx/efika.c
index 45c0cb9..18c1048 100644
--- a/arch/powerpc/platforms/52xx/efika.c
+++ b/arch/powerpc/platforms/52xx/efika.c
@@ -99,7 +99,7 @@ static void __init efika_pcisetup(void)
 	if (bus_range == NULL || len < 2 * sizeof(int)) {
 		printk(KERN_WARNING EFIKA_PLATFORM_NAME
 		       ": Can't get bus-range for %s\n", pcictrl->full_name);
-		return;
+		goto out_put;
 	}
 
 	if (bus_range[1] == bus_range[0])
@@ -111,12 +111,12 @@ static void __init efika_pcisetup(void)
 	printk(" controlled by %s\n", pcictrl->full_name);
 	printk("\n");
 
-	hose = pcibios_alloc_controller(of_node_get(pcictrl));
+	hose = pcibios_alloc_controller(pcictrl);
 	if (!hose) {
 		printk(KERN_WARNING EFIKA_PLATFORM_NAME
 		       ": Can't allocate PCI controller structure for %s\n",
 		       pcictrl->full_name);
-		return;
+		goto out_put;
 	}
 
 	hose->first_busno = bus_range[0];
@@ -124,6 +124,9 @@ static void __init efika_pcisetup(void)
 	hose->ops = &rtas_pci_ops;
 
 	pci_process_bridge_OF_ranges(hose, pcictrl, 0);
+	return;
+out_put:
+	of_node_put(pcictrl);
 }
 
 #else

powerpc/5200: efika.c: Add of_node_put to avoid memory leak

qlambert

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