commit 0930b25ee3a1eb28b957cdc70c9a1958812d895f
Author: NeilBrown <neilb@suse.de>
Date:   Thu May 8 05:18:25 2008 -0400

    If mount.nfs is not installed setuid, an attempt to perform a "user"
    or "users" mount will fail with a fairly obscure error message,
    typically about getting "permission denied" from the server.
    
    This patch gives a more helpful message in that case.
    
    Signed-off-by: NeilBrown <neilb@suse.de>
    Signed-off-by: Steve Dickson <steved@redhat.com>

diff --git a/utils/mount/mount.c b/utils/mount/mount.c
index 5076468..d7271a1 100644
--- a/utils/mount/mount.c
+++ b/utils/mount/mount.c
@@ -539,6 +539,12 @@ int main(int argc, char *argv[])
 			mnt_err = EX_USAGE;
 			goto out;
 		}
+
+		if (geteuid() != 0) {
+			nfs_error(_("%s: not installed setuid - "
+				    "\"user\" NFS mounts not supported."), progname);
+			exit(EX_FAIL);
+		}
 	}
 
 	if (chk_mountpoint(mount_point)) {