mount: don't call sd_device_get_property_value() with a NULL pointer

Otherwise bad thing would've happened is this was a hard assert:

+ systemd-mount --umount /dev/loop0
Assertion 'device' failed at src/libsystemd/sd-device/sd-device.c:2202, function sd_device_get_property_value(). Ignoring.

diff --git a/src/mount/mount-tool.c b/src/mount/mount-tool.c
index 5876e2ddb4739732db4a43dec77088f5120bbb0d..f626f07af63ad662a831aa9d4ee4f746f8fda3ee 100644 (file)
--- a/src/mount/mount-tool.c
+++ b/src/mount/mount-tool.c
@@ -975,7 +975,6 @@ static int stop_mounts(
 }
 
 static int umount_by_device(sd_bus *bus, sd_device *dev) {
-        _cleanup_(sd_device_unrefp) sd_device *d = NULL;
         _cleanup_strv_free_ char **list = NULL;
         const char *v;
         int r, ret = 0;
@@ -983,7 +982,7 @@ static int umount_by_device(sd_bus *bus, sd_device *dev) {
         assert(bus);
         assert(dev);
 
-        if (sd_device_get_property_value(d, "SYSTEMD_MOUNT_WHERE", &v) >= 0)
+        if (sd_device_get_property_value(dev, "SYSTEMD_MOUNT_WHERE", &v) >= 0)
                 ret = stop_mounts(bus, v);
 
         r = sd_device_get_devname(dev, &v);