mtd: lantiq-flash: drop iounmap for devm_ allocated data
Data allocated with devm_ioremap or devm_ioremap_nocache should not be
freed using iounmap, because doing so causes a dangling pointer, and a
subsequent double free.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@r@
expression x;
@@
(
x = devm_ioremap(...)
|
x = devm_ioremap_nocache(...)
)
@@
expression r.x;
@@
* iounmap(x)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/maps/lantiq-flash.c b/drivers/mtd/maps/lantiq-flash.c
index 4f10e27..7b889de 100644
--- a/drivers/mtd/maps/lantiq-flash.c
+++ b/drivers/mtd/maps/lantiq-flash.c
@@ -159,7 +159,7 @@
if (!ltq_mtd->mtd) {
dev_err(&pdev->dev, "probing failed\n");
err = -ENXIO;
- goto err_unmap;
+ goto err_free;
}
ltq_mtd->mtd->owner = THIS_MODULE;
@@ -179,8 +179,6 @@
err_destroy:
map_destroy(ltq_mtd->mtd);
-err_unmap:
- iounmap(ltq_mtd->map->virt);
err_free:
kfree(ltq_mtd->map);
err_out:
@@ -198,8 +196,6 @@
mtd_device_unregister(ltq_mtd->mtd);
map_destroy(ltq_mtd->mtd);
}
- if (ltq_mtd->map->virt)
- iounmap(ltq_mtd->map->virt);
kfree(ltq_mtd->map);
kfree(ltq_mtd);
}