[PATCH][next] clk: ls1028a: fix a dereference of pointer 'parent' before a null check

From: Colin King
Date: Mon Feb 03 2020 - 17:37:42 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

Currently the pointer 'parent' is being dereferenced before it is
being null checked. Fix this by performing the null check before
it is dereferenced.

Addresses-Coverity: ("Dereference before null check")
Fixes: d37010a3c162 ("clk: ls1028a: Add clock driver for Display output interface")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/clk/clk-plldig.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/clk/clk-plldig.c b/drivers/clk/clk-plldig.c
index a5da08f98d01..f7c349d9c2dc 100644
--- a/drivers/clk/clk-plldig.c
+++ b/drivers/clk/clk-plldig.c
@@ -187,7 +187,7 @@ static int plldig_init(struct clk_hw *hw)
{
struct clk_plldig *data = to_clk_plldig(hw);
struct clk_hw *parent = clk_hw_get_parent(hw);
- unsigned long parent_rate = clk_hw_get_rate(parent);
+ unsigned long parent_rate;
unsigned long val;
unsigned long long lltmp;
unsigned int mfd, fracdiv = 0;
@@ -195,6 +195,8 @@ static int plldig_init(struct clk_hw *hw)
if (!parent)
return -EINVAL;

+ parent_rate = clk_hw_get_rate(parent);
+
if (data->vco_freq) {
mfd = data->vco_freq / parent_rate;
lltmp = data->vco_freq % parent_rate;
--
2.24.0