libdm: check for empty aux_data in _parse_aux_data_group()

If after extracting stats arguments and group tags nothing remains
of aux_data but '-' set the region->aux_data field to the empty
string to match behaviour for non-grouped regions.

1 files changed, 1 insertions, 1 deletions

diff --git a/libdm/libdm-stats.c b/libdm/libdm-stats.c
index 12c821f23..e979b341c 100644
--- a/libdm/libdm-stats.c
+++ b/libdm/libdm-stats.c
@@ -692,7 +692,7 @@ static int _parse_aux_data_group(struct dm_stats *dms,
 	}
 
 	/* separate group tag from user aux_data */
-	if (strlen(end))
+	if ((strlen(end) > 1) || strncmp(end, "-", 1))
 		c = dm_strdup(end);
 	else
 		c = dm_strdup("");