2014-12-13 00:54:45

by Thomas Jarosch

[permalink] [raw]
Subject: [RFC PATCH, untested] Fix off-by-one in tps_comparators[] access

The array tps_comparators starts at zero,
yet COMP1 starts at 1. So COMP2 is out of bounds.

cppcheck reported:
[drivers/mfd/tps65911-comparator.c:61]: (error) Array 'tps_comparators[2]' accessed at index 2, which is out of bounds.
[drivers/mfd/tps65911-comparator.c:88]: (error) Array 'tps_comparators[2]' accessed at index 2, which is out of bounds.

Signed-off-by: Thomas Jarosch <[email protected]>
---
drivers/mfd/tps65911-comparator.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/mfd/tps65911-comparator.c b/drivers/mfd/tps65911-comparator.c
index c0816eb..e8c2e32 100644
--- a/drivers/mfd/tps65911-comparator.c
+++ b/drivers/mfd/tps65911-comparator.c
@@ -58,13 +58,14 @@ static struct comparator tps_comparators[] = {

static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)
{
- struct comparator tps_comp = tps_comparators[id];
+ struct comparator tps_comp;
int curr_voltage = 0;
int ret;
u8 index = 0, val;

- if (id == COMP)
+ if (id == COMP || id > COMP2)
return 0;
+ tps_comp = tps_comparators[id-1];

while (curr_voltage < tps_comp.uV_max) {
curr_voltage = tps_comp.vsel_table[index];
@@ -85,12 +86,13 @@ static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)

static int comp_threshold_get(struct tps65910 *tps65910, int id)
{
- struct comparator tps_comp = tps_comparators[id];
+ struct comparator tps_comp;
int ret;
u8 val;

- if (id == COMP)
+ if (id == COMP || id > COMP2)
return 0;
+ tps_comp = tps_comparators[id-1];

ret = tps65910->read(tps65910, tps_comp.reg, 1, &val);
if (ret < 0)
--
1.9.3