From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Cochran Subject: running binaries under doubly stacked overlayfs Date: Mon, 19 Sep 2016 21:10:10 +0200 Message-ID: <20160919191010.GC4246@netboy> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-wm0-f45.google.com ([74.125.82.45]:36280 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751327AbcISTKV (ORCPT ); Mon, 19 Sep 2016 15:10:21 -0400 Received: by mail-wm0-f45.google.com with SMTP id w84so93013141wmg.1 for ; Mon, 19 Sep 2016 12:10:20 -0700 (PDT) Received: from netboy (188-22-25-8.adsl.highway.telekom.at. [188.22.25.8]) by smtp.gmail.com with ESMTPSA id r8sm24525773wjs.22.2016.09.19.12.10.18 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Sep 2016 12:10:18 -0700 (PDT) Content-Disposition: inline Sender: linux-unionfs-owner@vger.kernel.org List-Id: linux-unionfs@vger.kernel.org To: linux-unionfs@vger.kernel.org Using kernel v3.18.41, something unexpected happens when I mount two overlays. Once the second overlay is mounted, the binaries won't execute any more. Below is a simple script to demonstate the issue. Although this uses a shell script, the same thing happens with actual binaries. What am I doing wrong here? Thanks, Richard ---8<--- cd /tmp mkdir merged layer1 layer2 w1 w2 touch layer1/.layer1 layer2/.layer2 cat > merged/helo.sh <<-EOF #!/bin/sh echo helo EOF chmod +x merged/helo.sh mount -t overlay overlay \ -oro,lowerdir=/tmp/merged,upperdir=/tmp/layer1,workdir=/tmp/w1 /tmp/merged ./merged/helo.sh # works as expected mount -t overlay overlay \ -orw,lowerdir=/tmp/merged,upperdir=/tmp/layer2,workdir=/tmp/w2 /tmp/merged ./merged/helo.sh # -bash: ./merged/helo.sh: Invalid argument