[PATCH] mfd: menelaus: remove null pointer dereference

From: Himangi Saraogi
Date: Sat Aug 09 2014 - 12:40:50 EST


If vtg is NULL, it is not possible to access its mode_reg field. At all
sites where the static function menelaus_set_voltage is called, the first
argument is the address of a structure defined in the file. So, the null
test is unnecessary and is removed. Also, a label is done away with.

This problem was found using the following Coccinelle semantic match:

// <smpl>
@@
expression E, E1;
identifier f;
statement S1,S2,S3;
@@

* if (E == NULL)
{
... when != if (E == NULL) S1 else S2
when != E = E1
* E->f
... when any
return ...;
}
else S3
// </smpl>

Signed-off-by: Himangi Saraogi <himangi774@xxxxxxxxx>
Acked-by: Julia Lawall <julia.lawall@xxxxxxx>
---
Not compile tested.
drivers/mfd/menelaus.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/drivers/mfd/menelaus.c b/drivers/mfd/menelaus.c
index 5e2667a..18ff56f 100644
--- a/drivers/mfd/menelaus.c
+++ b/drivers/mfd/menelaus.c
@@ -466,8 +466,6 @@ static int menelaus_set_voltage(const struct menelaus_vtg *vtg, int mV,
struct i2c_client *c = the_menelaus->client;

mutex_lock(&the_menelaus->lock);
- if (!vtg)
- goto set_voltage;

ret = menelaus_read_reg(vtg->vtg_reg);
if (ret < 0)
@@ -482,7 +480,6 @@ static int menelaus_set_voltage(const struct menelaus_vtg *vtg, int mV,
ret = menelaus_write_reg(vtg->vtg_reg, val);
if (ret < 0)
goto out;
-set_voltage:
ret = menelaus_write_reg(vtg->mode_reg, mode);
out:
mutex_unlock(&the_menelaus->lock);
--
1.9.1

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