From dfaf2471932a0e7d7623bdae33be57ba2174c9f9 Mon Sep 17 00:00:00 2001
From: Steve Langasek <steve.langasek@canonical.com>
Date: Sat, 21 Oct 2017 00:54:02 -0700
Subject: [PATCH] Properly handle loop device names when there are > 10 devices
 on the system.

---
 debian/changelog     | 2 ++
 live-build/functions | 2 +-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/debian/changelog b/debian/changelog
index 33b74471..7b71efe3 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,8 @@
 livecd-rootfs (2.479) UNRELEASED; urgency=medium
 
   * Purge initramfs-tools from minimized images.
+  * Properly handle loop device names when there are > 10 devices on the
+    system.
 
  -- Steve Langasek <steve.langasek@ubuntu.com>  Fri, 13 Oct 2017 17:14:58 -0400
 
diff --git a/live-build/functions b/live-build/functions
index f05aaf8e..03ede971 100644
--- a/live-build/functions
+++ b/live-build/functions
@@ -56,7 +56,7 @@ mount_image() {
 
     # Find the loop device
     loop_p1="$(echo -e ${kpartx_mapping} | head -n1 | awk '{print$3}')"
-    loop_device="/dev/loop$(echo ${loop_p1} | cut -b5)"
+    loop_device="/dev/${loop_p1%p[0-9]*}"
     if [ ! -b ${loop_device} ]; then
         echo "unable to find loop device for ${backing_img}"
         exit 1