diff --git a/src/base/system.c b/src/base/system.c
index 027ab204c..9e84fce67 100644
--- a/src/base/system.c
+++ b/src/base/system.c
@@ -2179,7 +2179,7 @@ void str_append(char *dst, const char *src, int dst_size)
 
 void str_copy(char *dst, const char *src, int dst_size)
 {
-	strncpy(dst, src, dst_size);
+	strncpy(dst, src, dst_size-1);
 	dst[dst_size-1] = 0; /* assure null termination */
 }