[PATCH 9/10] drivers/ata: introduce missing kfree

[PATCH 9/10] drivers/ata: introduce missing kfree

[Julia Lawall]

From: Julia Lawall <julia@diku.dk>

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

The semantic match that finds the 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@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@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@diku.dk>
---
 drivers/ata/pata_at91.c             |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
index 5702aff..46fb883 100644
--- a/drivers/ata/pata_at91.c
+++ b/drivers/ata/pata_at91.c
@@ -261,7 +261,8 @@ static int __devinit pata_at91_probe(struct platform_device *pdev)
 
 	if (IS_ERR(info->mck)) {
 		dev_err(dev, "failed to get access to mck clock\n");
-		return -ENODEV;
+		ret = -ENODEV;
+		goto err_clk_get;
 	}
 
 	info->cs    = board->chipselect;
@@ -308,6 +309,7 @@ err_alt_ioremap:
 
 err_ide_ioremap:
 	clk_put(info->mck);
+err_clk_get:
 	kfree(info);
 
 	return ret;

Re: [PATCH 9/10] drivers/ata: introduce missing kfree

[Tejun Heo]

Julia Lawall wrote:
...
> ---
>  drivers/ata/pata_at91.c             |    4 +++-
>  1 files changed, 3 insertions(+), 1 deletions(-)
> 
> diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
> index 5702aff..46fb883 100644
> --- a/drivers/ata/pata_at91.c
> +++ b/drivers/ata/pata_at91.c
> @@ -261,7 +261,8 @@ static int __devinit pata_at91_probe(struct platform_device *pdev)
>  
>  	if (IS_ERR(info->mck)) {
>  		dev_err(dev, "failed to get access to mck clock\n");
> -		return -ENODEV;
> +		ret = -ENODEV;
> +		goto err_clk_get;
>  	}
>  
>  	info->cs    = board->chipselect;
> @@ -308,6 +309,7 @@ err_alt_ioremap:
>  
>  err_ide_ioremap:
>  	clk_put(info->mck);
> +err_clk_get:
>  	kfree(info);

cc'ing Matyukevich Sergey.  Matyukevich, is it possible to use
devm_kzalloc() instead?

Thanks.

-- 
tejun