[PATCH] scsi: ufs: ufshcd: fix potential NULL pointer dereference in ufshcd_config_vreg

From: Gustavo A. R. Silva
Date: Mon Nov 20 2017 - 09:12:45 EST


_vreg_ is being dereferenced before it is null checked, hence there is a
potential null pointer dereference.

Fix this by moving the pointer dereference after _vreg_ has been null
checked.

This issue was detected with the help of Coccinelle.

Fixes: aa4976130934 ("ufs: Add regulator enable support")
Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
---
drivers/scsi/ufs/ufshcd.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 011c336..a355d98 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6559,12 +6559,15 @@ static int ufshcd_config_vreg(struct device *dev,
struct ufs_vreg *vreg, bool on)
{
int ret = 0;
- struct regulator *reg = vreg->reg;
- const char *name = vreg->name;
+ struct regulator *reg;
+ const char *name;
int min_uV, uA_load;

BUG_ON(!vreg);

+ reg = vreg->reg;
+ name = vreg->name;
+
if (regulator_count_voltages(reg) > 0) {
min_uV = on ? vreg->min_uV : 0;
ret = regulator_set_voltage(reg, min_uV, vreg->max_uV);
--
2.7.4