[PATCH AUTOSEL for 4.4 32/35] scsi: ufs: ufshcd: fix potential NULL pointer dereference in ufshcd_config_vreg

Sasha Levin
2018-01-24T04:20:03Z

From: "Gustavo A. R. Silva" <garsilva@embeddedor.com>

[ Upstream commit 727535903bea924c4f73abb202c4b3e85fff0ca4 ]

_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@embeddedor.com>
Reviewed-by: Subhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
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 0c2482ec7d21..096c867069e9 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -4392,12 +4392,15 @@ 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);
--
2.11.0