am-utils-6.2 - fix NFSv3 lookup dir attribute return value

From: Ian Kent <raven@themaw.net>

The NFS v3 lookup method, which returns attributes for the directory
containing the object to be looked up, used incorrect mount point
attributes which was causing unusual file system object visibility
problems.

Signed-off-by: Ian Kent <raven@themaw.net>
---
 amd/nfs_subr.c |   29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/amd/nfs_subr.c b/amd/nfs_subr.c
index 85cf98c..6a1b717 100644
--- a/amd/nfs_subr.c
+++ b/amd/nfs_subr.c
@@ -978,6 +978,29 @@ static void fattr_to_wcc_attr(nfsfattr *fattr, am_wcc_attr *wcc_attr)
   nfstime_to_am_nfstime3(&fattr->na_ctime, &wcc_attr->ctime);
 }
 
+static nfsfattr *get_parent_fattr(am_node *mp)
+{
+  nfsfattr *fattr;
+
+  /* Set attributes to those of the parent only if this
+   * isn't topvol otherwise just use the mp attributes.
+   */
+  fattr = &mp->am_fattr;
+  if (mp->am_parent && mp->am_parent->am_parent &&
+      !(mp->am_parent->am_parent->am_flags & AMF_ROOT))
+    fattr = &mp->am_parent->am_fattr;
+
+  return fattr;
+}
+
+static void parent_fattr_to_fattr3(am_node *mp, am_fattr3 *fattr3)
+{
+  nfsfattr *fattr;
+
+  fattr = get_parent_fattr(mp);
+  fattr_to_fattr3(fattr, fattr3);
+}
+
 static am_nfsstat3 return_estale_or_rofs(am_nfs_fh3 *fh,
                                          am_pre_op_attr *pre_op,
                                          am_post_op_attr *post_op)
@@ -1177,9 +1200,7 @@ am_nfs3_lookup_3_svc(am_LOOKUP3args *argp, struct svc_req *rqstp)
 
     /* dir attributes */
     post_op_dir->attributes_follow = 1;
-    fattr = &mp->am_fattr;
     fattr3 = &post_op_dir->am_post_op_attr_u.attributes;
-    fattr_to_fattr3(fattr, fattr3);
 
     post_op_obj->attributes_follow = 0;
 
@@ -1196,6 +1217,7 @@ am_nfs3_lookup_3_svc(am_LOOKUP3args *argp, struct svc_req *rqstp)
 	amd_stats.d_drops++;
 	return 0;
       }
+      parent_fattr_to_fattr3(mp, fattr3);
       result.status = nfs_error(error);
     } else {
       /*
@@ -1206,6 +1228,9 @@ am_nfs3_lookup_3_svc(am_LOOKUP3args *argp, struct svc_req *rqstp)
       if (ap->am_ttl < mp->am_ttl)
         ap->am_ttl = mp->am_ttl;
 
+      /* dir attrs, update after mount */
+      parent_fattr_to_fattr3(mp, fattr3);
+
       mp_to_fh3(ap, &result.res_u.ok.object);
 
       /* mount attributes */