From b224f888c225d9735abaa82d0156ae5a4c38d4f5 Mon Sep 17 00:00:00 2001
From: Vendula Poncova <vponcova@redhat.com>
Date: Fri, 18 Sep 2020 15:13:14 +0200
Subject: [PATCH] Never mount partitions on a disk with the iso9660 filesystem

Blivet doesn't recognize these partitions, so we mount the disk in stage2.
However, it will fail if one of its partitions is already mounted, for example
in stage1. Therefore, skip these partitions in the script that looks for a root
image on devices and use the disk instead.

The boot.iso has the following structure:

NAME   TYPE  SIZE FSTYPE  LABEL
sda    disk  8.8G iso9660 RHEL-8-3-0-BaseOS-x86_64
|-sda1 part  8.8G iso9660 RHEL-8-3-0-BaseOS-x86_64
`-sda2 part   10M vfat    ANACONDA

And the following default boot options:

inst.stage2=hd:LABEL=RHEL-8-3-0-BaseOS-x86_64 rd.live.check quiet

Anaconda runs the anaconda-diskroot script for every device that matches the
specification from the inst.stage2 option. In this example, it is sda and sda1,
because both of them have the specified label RHEL-8-3-0-BaseOS-x86_64. With
the fix, the script will detect that sda1 is a partition on a disk with the
iso9660 filesystem and stop to process sda1. The script will succeed with sda.

We should never rely on the order of the devices.

(cherry-picked from a commit 301a09d)

Related: rhbz#1878784
---
 dracut/anaconda-diskroot | 17 ++++++++++++++++-
 dracut/anaconda-lib.sh   | 22 ++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/dracut/anaconda-diskroot b/dracut/anaconda-diskroot
index 8846b1108..2797e6762 100755
--- a/dracut/anaconda-diskroot
+++ b/dracut/anaconda-diskroot
@@ -41,7 +41,22 @@ dev="$1"
 path="$2" # optional, could be empty
 kickstart="$(getarg ks= inst.ks=)"
 
-[ -e "/dev/root" ] && exit 1 # we already have a root device!
+# Log the device that triggered this job.
+debug_msg "Trying to find a root image on the device $dev."
+
+# Do we already have a root device?
+# Then do not run again.
+[ -e "/dev/root" ] && exit 1
+
+# Skip partitions on a disk with the iso9660 filesystem. Blivet doesn't
+# recognize these partitions, so we mount the disk in stage2. However, it
+# will fail if one of its partitions is already mounted, for example here.
+# Therefore, skip the partitions and use the disk to find our root image.
+# See the bug 1878784.
+if dev_is_on_disk_with_iso9660 "$dev"; then
+  debug_msg "Skipping $dev on a disk with iso9660."
+  exit 1
+fi
 
 # If we're waiting for a cdrom kickstart, the user might need to swap discs.
 # So if this is a CDROM drive, make a note of it, but don't mount it (yet).
diff --git a/dracut/anaconda-lib.sh b/dracut/anaconda-lib.sh
index e2ab7a205..3b86f3df9 100755
--- a/dracut/anaconda-lib.sh
+++ b/dracut/anaconda-lib.sh
@@ -253,6 +253,28 @@ dev_is_cdrom() {
     udevadm info --query=property --name=$1 | grep -q 'ID_CDROM=1'
 }
 
+dev_is_on_disk_with_iso9660() {
+    # Get the name of the device.
+    local dev_name="${1}"
+
+    # Get the path of the device.
+    local dev_path="$(udevadm info -q path --name ${dev_name})"
+
+    # Is the device a partition?
+    udevadm info -q property --path ${dev_path} | grep -q 'DEVTYPE=partition' || return 1
+
+    # Get the path of the parent.
+    local disk_path="${dev_path%/*}"
+
+    # Is the parent a disk?
+    udevadm info -q property --path ${disk_path} | grep -q 'DEVTYPE=disk' || return 1
+
+    # Does the parent has the iso9660 filesystem?
+    udevadm info -q property --path ${disk_path} | grep -q 'ID_FS_TYPE=iso9660' || return 1
+
+    return 0
+}
+
 # dracut doesn't bring up the network unless:
 #   a) $netroot is set (i.e. you have a network root device), or
 #   b) /tmp/net.ifaces exists.
-- 
2.23.0