From 1430ee73b566a30bc210501d1e0e99c519707f1e Mon Sep 17 00:00:00 2001 From: Peter Wu Date: Thu, 11 Dec 2014 13:51:18 +0100 Subject: [PATCH] HID: logitech-hidpp: check name retrieval return code hidpp_devicenametype_get_device_name() may return a negative value on protocol errors (for example, when the device is powered off). Explicitly check this condition to avoid a long-running loop. (0 cannot be returned as __name_length - index > 0, but check for it anyway as it would otherwise result in an infinite loop.) Signed-off-by: Peter Wu Reviewed-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-logitech-hidpp.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c index 5066df8afee5..4d72c20fa233 100644 --- a/drivers/hid/hid-logitech-hidpp.c +++ b/drivers/hid/hid-logitech-hidpp.c @@ -484,10 +484,16 @@ static char *hidpp_get_device_name(struct hidpp_device *hidpp) if (!name) return NULL; - while (index < __name_length) - index += hidpp_devicenametype_get_device_name(hidpp, + while (index < __name_length) { + ret = hidpp_devicenametype_get_device_name(hidpp, feature_index, index, name + index, __name_length - index); + if (ret <= 0) { + kfree(name); + return NULL; + } + index += ret; + } return name; } -- 2.20.1