dmstats: don't output column headings if report fails

If _stats_report fails (e.g. due to an invalid device on the
command line) destroy the _report to prevent stats columns headings
from being displayed.

This also requires a change in main to test the return from
_perform_command_for_all_repeatable_args inside the interval loop
and exit immediately in case of error.

1 files changed, 7 insertions, 0 deletions

diff --git a/tools/dmsetup.c b/tools/dmsetup.c
index e913a7edf..dd2f1539f 100644
--- a/tools/dmsetup.c
+++ b/tools/dmsetup.c
@@ -4692,6 +4692,10 @@ static int _stats_report(CMD_ARGS)
 
       out:
 	dm_task_destroy(dmt);
+	if (!r && _report) {
+		dm_report_free(_report);
+		_report = NULL;
+	}
 	return r;
 }
 
@@ -5838,6 +5842,9 @@ doit:
 					goto_out;
 			}
 		}
+
+		if (r)
+			break;
 	} while (--_count);
 
 out: