[alsa-devel] [PATCH 8/8] sound/soc: introduce missing kfree

[Julia Lawall]

From: Julia Lawall <julia at diku.dk>

Error handling code following a kzalloc should free the allocated data.
Error handling code following an ioremap should iounmap the allocated data.

The semantic match that finds the first problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x at p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return at p2 ...;
)

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

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Julia Lawall <julia at diku.dk>
---
 sound/soc/fsl/mpc5200_dma.c         |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/sound/soc/fsl/mpc5200_dma.c b/sound/soc/fsl/mpc5200_dma.c
index 9ff62e3..41ffd57 100644
--- a/sound/soc/fsl/mpc5200_dma.c
+++ b/sound/soc/fsl/mpc5200_dma.c
@@ -469,8 +469,11 @@ int mpc5200_audio_dma_create(struct of_device *op)
 
 	/* Get the PSC ID */
 	prop = of_get_property(op->node, "cell-index", &size);
-	if (!prop || size < sizeof *prop)
+	if (!prop || size < sizeof *prop) {
+		iounmap(regs);
+		kfree(psc_dma);
 		return -ENODEV;
+	}
 
 	spin_lock_init(&psc_dma->lock);
 	mutex_init(&psc_dma->mutex);