du: ignore directory cycles due to bind mounts

* src/du.c (process_file): Treat cycles due to bind mounts
like cycles due to following symlinks.
* tests/du/bind-mount-dir-cycle.sh: Adjust accordingly.
* NEWS: Mention the change in behavior.
Reported at http://bugzilla.redhat.com/836557

1 files changed, 4 insertions, 8 deletions

diff --git a/src/du.c b/src/du.c
index e4509fd78..0966326b5 100644
--- a/src/du.c
+++ b/src/du.c
@@ -514,15 +514,11 @@ process_file (FTS *fts, FTSENT *ent)
           break;
 
         case FTS_DC:
-          if (cycle_warning_required (fts, ent))
+          /* If not following symlinks and not a (bind) mount point.  */
+          if (cycle_warning_required (fts, ent)
+              && ! di_set_lookup (di_mnt, sb->st_dev, sb->st_ino))
             {
-              /* If this is a mount point, then diagnose it and avoid
-                 the cycle.  */
-              if (di_set_lookup (di_mnt, sb->st_dev, sb->st_ino))
-                error (0, 0, _("mount point %s already traversed"),
-                       quote (file));
-              else
-                emit_cycle_warning (file);
+              emit_cycle_warning (file);
               return false;
             }
           return true;