cros_ec: fix nul-termination for firmware build info

[ Upstream commit 50a0d71a5d20e1d3eff1d974fdc8559ad6d74892 ]

As gcc-8 reports, we zero out the wrong byte:

drivers/platform/chrome/cros_ec_sysfs.c: In function 'show_ec_version':
drivers/platform/chrome/cros_ec_sysfs.c:190:12: error: array subscript 4294967295 is above array bounds of 'uint8_t[]' [-Werror=array-bounds]

This changes the code back to what it did before changing to a
zero-length array structure.

Fixes: a841178445bb ("mfd: cros_ec: Use a zero-length array for command data")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Benson Leung <bleung@chromium.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/platform/chrome/cros_ec_sysfs.c b/drivers/platform/chrome/cros_ec_sysfs.c
index f3baf99..24f1630 100644 (file)
--- a/drivers/platform/chrome/cros_ec_sysfs.c
+++ b/drivers/platform/chrome/cros_ec_sysfs.c
@@ -187,7 +187,7 @@ static ssize_t show_ec_version(struct device *dev,
                count += scnprintf(buf + count, PAGE_SIZE - count,
                                   "Build info:    EC error %d\n", msg->result);
        else {
-               msg->data[sizeof(msg->data) - 1] = '\0';
+               msg->data[EC_HOST_PARAM_SIZE - 1] = '\0';
                count += scnprintf(buf + count, PAGE_SIZE - count,
                                   "Build info:    %s\n", msg->data);
        }