greybus: connection: prevent oops for protocol_id sysfs file

If we don't have a protocol assigned to a connection, don't oops when
trying to read the "protocol_id" sysfs file.

Fixes Jira SW-968.

Reported-by: Alexandre Bailon <abailon@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
This commit is contained in:
Greg Kroah-Hartman 2015-07-22 18:21:04 -07:00
parent 155b9f175e
commit 2975617421

View file

@ -80,7 +80,10 @@ protocol_id_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct gb_connection *connection = to_gb_connection(dev);
return sprintf(buf, "%d\n", connection->protocol->id);
if (connection->protocol)
return sprintf(buf, "%d\n", connection->protocol->id);
else
return -EINVAL;
}
static DEVICE_ATTR_RO(protocol_id);