drivers/ata: introduce missing kfree

From: Julia Lawall <[email protected]>

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>

---

 drivers/ata/pata_at91.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff -puN drivers/ata/pata_at91.c~drivers-ata-introduce-missing-kfree drivers/ata/pata_at91.c
@@ -261,7 +261,8 @@ static int __devinit pata_at91_probe(str
 
 	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;

_