[Bug 1235975] Re: Unsafe file and directory permissions

[Barry Warsaw]

stgraber also suggested in IRC that /tmp may not be a good idea since
that's tmpfs backed and possibly limited in size.   The base directory
is configurable in /etc/system-image/client.ini but maybe /var/tmp
/system-image would be a better default base dir.  It would have to be
made writable though.

I suggest using tmpfile.mkdtemp() to provide a secure unpredictable
temporary directory inside that basedir for a download session.  One
implication of this though is that if the s-i-dbus process exits, it
really should clean up this temporary, er temporary directory.  Which
means that once it exits, the downloaded files will be discarded.  So
if, as in LP: #1236818 you start the download, but leave your phone
unattended for long enough, s-i-dbus will exit and you'll have to
restart the whole process again.

Or, I suppose, that temporary temporary directory could be cleaned up
only prior to apply-and-reboot, and if the process exits due to timing
out, we'd have to persist the fact that that tempdir was created.  I'll
leave that to LP: #1236818.

** Changed in: ubuntu-system-image
       Status: Triaged => In Progress

** Changed in: ubuntu-system-image
    Milestone: None => 1.9

** Changed in: system-image (Ubuntu)
       Status: New => In Progress

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to system-image in Ubuntu.
https://bugs.launchpad.net/bugs/1235975

Title:
  Unsafe file and directory permissions

Status in Ubuntu system image (server/client/updater):
  In Progress
Status in “system-image” package in Ubuntu:
  In Progress

Bug description:
  # ls -ld /var/log/system-image/
  drwxrwxrwx 2 root root 4096 Sep 24 16:02 /var/log/system-image/
  # ls -l /var/log/system-image/client.log 
  -rw-rw-rw- 1 root root 23927 Oct  6 09:11 /var/log/system-image/client.log
  # ls -ld /tmp/system-image/
  drwxrwxrwx 2 root root 260 Oct  6 09:11 /tmp/system-image/

  Also, predictable temporary file (/tmp/system-image). This was
  mentioned in bug #1233521

  # system-image-cli -i
  current build number: 78
  device name: mako
  channel: stable
  last update: 2013-10-03 13:05:32
  version version: 78
  version ubuntu: 20131003
  version device: 20131002.1

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu-system-image/+bug/1235975/+subscriptions