Bug#840372: debootstrap: second-stage fails within systemd-nspawn: proc already mounted

[Hideki Yamane <henrich@iijmio-mail.jp>]

On Thu, 19 Apr 2018 10:06:49 +0200
Raphael Hertzog <hertzog@debian.org> wrote:
> Your patch will try to umount /proc even if it has not been mounted by
> debootstrap. That's wrong. If you detect that /proc was handled outside of
> debootstrap, then you should also not umount it.

+               if [ ! -n "$(ls -A /proc)" ]; then
+                       in_target mount -t proc proc /proc

 is when there's no file under /proc, then try to mount /proc - not try
 to umount it.


> And the handling of /sys should be entirely separate from /proc. Even if
> /proc was already mounted, you want debootstrap to ensure that /sys is
> mounted too.

 Okay, it should be that.


diff --git a/functions b/functions
index 1e41862..cb2c1d9 100644
--- a/functions
+++ b/functions
@@ -1137,10 +1137,12 @@ setup_proc () {
                # and also fix failure on lxc environment
                if [ ! -n "$(ls -A /proc)" ]; then
                        in_target mount -t proc proc /proc
-                       if [ -d "$TARGET/sys" ] && \
-                          grep -q '[[:space:]]sysfs' /proc/filesystems 2>/dev/null; then
-                               umount_on_exit /sys
-                               umount "$TARGET/sys" 2>/dev/null || true
+               fi
+               if [ -d "$TARGET/sys" ] && \
+                  grep -q '[[:space:]]sysfs' /proc/filesystems 2>/dev/null; then
+                       umount_on_exit /sys
+                       umount "$TARGET/sys" 2>/dev/null || true
+                       if [ ! -n "$(ls -A /sys)" ]; then
                                in_target mount -t sysfs sysfs /sys
                        fi
                fi