[PATCH] df: avoid suppressing remote mounts of separate exports

[Pádraig Brady]

* src/df.c (filter_mount_list): Separate remote locations may
have different ACLs etc. so list each even if they share
the same remote device and thus storage.
* NEWS: Mention the change in behavior.

Reported in http://bugs.debian.org/737399
Reported in http://bugzilla.redhat.com/920806
---
 NEWS     |    6 ++++++
 src/df.c |   33 +++++++++++++++++++++------------
 2 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/NEWS b/NEWS
index 5fbdc6a..6dda9f5 100644
--- a/NEWS
+++ b/NEWS
@@ -30,6 +30,12 @@ GNU coreutils NEWS                                    -*- 
outline -*-
   dd accepts a new status=progress level to print data transfer statistics
   on stderr approximately every second.
 
+** Changes in behavior
+
+  df no longer suppresses separate exports of the same remote device,
+  as these are probably explicitly mounted and may have separate ACLs etc.
+  [suppression was introduced in coreutils-8.21]
+
 ** Improvements
 
   cp,install,mv will convert smaller runs of NULs in the input to holes,
diff --git a/src/df.c b/src/df.c
index a52afc4..cf0d433 100644
--- a/src/df.c
+++ b/src/df.c
@@ -640,18 +640,27 @@ filter_mount_list (bool devices_only)
 
           if (devlist)
             {
-                  /* let "real" devices with '/' in the name win.  */
-              if ((strchr (me->me_devname, '/')
-                   && ! strchr (devlist->me->me_devname, '/'))
-                  /* let a shorter mountdir win.  */
-                  || (strlen (devlist->me->me_mountdir)
-                      > strlen (me->me_mountdir))
-                  /* let an entry overmounted on a different device win...  */
-                  || (! STREQ (devlist->me->me_devname, me->me_devname)
-                      /* ... but only when matching an existing mount point, to
-                      avoid problematic replacement when given inaccurate mount
-                      lists, seen with some chroot environments for example.  
*/
-                      && STREQ (me->me_mountdir, devlist->me->me_mountdir)))
+              if (me->me_remote && devlist->me->me_remote
+                  && ! STREQ (devlist->me->me_devname, me->me_devname))
+                {
+                  /* Don't discard remote entries with different locations,
+                     as there may be differing ACLs etc. per remote path, and
+                     also these are more likely to be explicitly mounted.  */
+                }
+              else if ((strchr (me->me_devname, '/')
+                       /* let "real" devices with '/' in the name win.  */
+                        && ! strchr (devlist->me->me_devname, '/'))
+                       /* let a shorter mountdir win.  */
+                       || (strlen (devlist->me->me_mountdir)
+                           > strlen (me->me_mountdir))
+                       /* let an entry overmounted on a new device win...  */
+                       || (! STREQ (devlist->me->me_devname, me->me_devname)
+                           /* ... but only when matching an existing mnt point,
+                              to avoid problematic replacement when given
+                              inaccurate mount lists, seen with some chroot
+                              environments for example.  */
+                           && STREQ (me->me_mountdir,
+                                     devlist->me->me_mountdir)))
                 {
                   /* Discard mount entry for existing device.  */
                   discard_me = devlist->me;
-- 
1.7.7.6