[PATCH 3/4] regulator/wm831x-ldo: fix potential NULL dereference

From: Axel Lin
Date: Thu Aug 19 2010 - 21:58:42 EST


pdata is dereferenced earlier than tested for being NULL.
Thus move the dereference of "pdata" below the check for NULL.

Signed-off-by: Axel Lin <axel.lin@xxxxxxxxx>
---
drivers/regulator/wm831x-ldo.c | 27 ++++++++++++++++++---------
1 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/drivers/regulator/wm831x-ldo.c b/drivers/regulator/wm831x-ldo.c
index e686cdb..040515d 100644
--- a/drivers/regulator/wm831x-ldo.c
+++ b/drivers/regulator/wm831x-ldo.c
@@ -303,14 +303,17 @@ static __devinit int wm831x_gp_ldo_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *pdata = wm831x->dev->platform_data;
- int id = pdev->id % ARRAY_SIZE(pdata->ldo);
struct wm831x_ldo *ldo;
struct resource *res;
- int ret, irq;
+ int id, ret, irq;

+ if (pdata == NULL)
+ return -ENODEV;
+
+ id = pdev->id % ARRAY_SIZE(pdata->ldo);
dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);

- if (pdata == NULL || pdata->ldo[id] == NULL)
+ if (pdata->ldo[id] == NULL)
return -ENODEV;

ldo = kzalloc(sizeof(struct wm831x_ldo), GFP_KERNEL);
@@ -563,14 +566,17 @@ static __devinit int wm831x_aldo_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *pdata = wm831x->dev->platform_data;
- int id = pdev->id % ARRAY_SIZE(pdata->ldo);
struct wm831x_ldo *ldo;
struct resource *res;
- int ret, irq;
+ int id, ret, irq;
+
+ if (pdata == NULL)
+ return -ENODEV;

+ id = pdev->id % ARRAY_SIZE(pdata->ldo);
dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);

- if (pdata == NULL || pdata->ldo[id] == NULL)
+ if (pdata->ldo[id] == NULL)
return -ENODEV;

ldo = kzalloc(sizeof(struct wm831x_ldo), GFP_KERNEL);
@@ -749,14 +755,17 @@ static __devinit int wm831x_alive_ldo_probe(struct platform_device *pdev)
{
struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *pdata = wm831x->dev->platform_data;
- int id = pdev->id % ARRAY_SIZE(pdata->ldo);
struct wm831x_ldo *ldo;
struct resource *res;
- int ret;
+ int id, ret;
+
+ if (pdata == NULL)
+ return -ENODEV;

+ id = pdev->id % ARRAY_SIZE(pdata->ldo);
dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);

- if (pdata == NULL || pdata->ldo[id] == NULL)
+ if (pdata->ldo[id] == NULL)
return -ENODEV;

ldo = kzalloc(sizeof(struct wm831x_ldo), GFP_KERNEL);
--
1.7.2



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