2015-12-22 17:44:23

by Sasha Levin

[permalink] [raw]
Subject: [PATCH] power, test_power: correctly handle empty writes

Writing 0 length data into test_power makes it access an invalid array
location and kill the system.

Fixes: f17ef9b2d ("power: Make test_power driver more dynamic.")
Signed-off-by: Sasha Levin <[email protected]>
---
drivers/power/test_power.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/power/test_power.c b/drivers/power/test_power.c
index 83c42ea..57246cd 100644
--- a/drivers/power/test_power.c
+++ b/drivers/power/test_power.c
@@ -301,6 +301,8 @@ static int map_get_value(struct battery_property_map *map, const char *key,
buf[MAX_KEYLENGTH-1] = '\0';

cr = strnlen(buf, MAX_KEYLENGTH) - 1;
+ if (cr < 0)
+ return def_val;
if (buf[cr] == '\n')
buf[cr] = '\0';

--
1.7.10.4