diff --git a/src/borg/archive.py b/src/borg/archive.py
index 279a0e131..728c76bb1 100644
--- a/src/borg/archive.py
+++ b/src/borg/archive.py
@@ -1447,7 +1447,7 @@ class TarfileObjectProcessors:
     def create_helper(self, tarinfo, status=None, type=None):
         item = Item(path=make_path_safe(tarinfo.name), mode=tarinfo.mode | type,
                     uid=tarinfo.uid, gid=tarinfo.gid, user=tarinfo.uname or None, group=tarinfo.gname or None,
-                    mtime=tarinfo.mtime * 1000**3)
+                    mtime=safe_ns(int(tarinfo.mtime * 1000**3)))
         yield item, status
         # if we get here, "with"-block worked ok without error/exception, the item was processed ok...
         self.add_item(item, stats=self.stats)
diff --git a/src/borg/helpers/process.py b/src/borg/helpers/process.py
index bf87869f6..7af8d5fcb 100644
--- a/src/borg/helpers/process.py
+++ b/src/borg/helpers/process.py
@@ -329,6 +329,14 @@ def create_filter_process(cmd, stream, stream_close, inbound=True):
     try:
         yield stream
 
+    except Exception:
+        # something went wrong with processing the stream by borg
+        logger.debug('Exception, killing the filter...')
+        proc.kill()
+        borg_succeeded = False
+        raise
+    else:
+        borg_succeeded = True
     finally:
         if stream_close:
             stream.close()
@@ -339,5 +347,6 @@ def create_filter_process(cmd, stream, stream_close, inbound=True):
             logger.debug('filter cmd exited with code %d', rc)
             if filter_stream_close:
                 filter_stream.close()
-            if rc:
+            if borg_succeeded and rc:
+                # if borg did not succeed, we know that we killed the filter process
                 raise Error('filter %s failed, rc=%d' % (cmd, rc))