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Editing File: /etc/apparmor.d/abstractions/ubuntu-helpers

# Lenient profile that is intended to be used when 'Ux' is desired but
# does not provide enough environment sanitizing. This effectively is an
# open profile that blacklists certain known dangerous files and also
# does not allow any capabilities. For example, it will not allow 'm' on files
# owned be the user invoking the program. While this provides some additional
# protection, please use with care as applications running under this profile
# are effectively running without any AppArmor protection. Use this profile
# only if the process absolutely must be run (effectively) unconfined.
#
# Usage:
# Because this abstraction defines the sanitized_helper profile, it must only
# be #included once. Therefore this abstraction should typically not be
# included in other abstractions so as to avoid parser errors regarding
# multiple definitions.
#
# Limitations:
# 1. This does not work for root owned processes, because of the way we use
#    owner matching in the sanitized helper. We could do a better job with
#    this to support root, but it would make the policy harder to understand
#    and going unconfined as root is not desirable any way.
#
# 2. For this sanitized_helper to work, the program running in the sanitized
#    environment must open symlinks directly in order for AppArmor to mediate
#    it. This is confirmed to work with:
#     - compiled code which can load shared libraries
#     - python imports
#    It is known not to work with:
#     - perl includes
# 3. Sanitizing ruby and java
#
# Use at your own risk. This profile was developed as an interim workaround for
# LP: #851986 until AppArmor utilizes proper environment filtering.

profile sanitized_helper {
  #include <abstractions/base>
  #include <abstractions/X>

# Allow all networking
  network inet,
  network inet6,

# Allow all DBus communications
  #include <abstractions/dbus-session-strict>
  #include <abstractions/dbus-strict>
  dbus,

# Needed for Google Chrome
  ptrace (trace) peer=**//sanitized_helper,

# Allow exec of anything, but under this profile. Allow transition
  # to other profiles if they exist.
  /{usr/,usr/local/,}{bin,sbin}/* Pixr,

# Allow exec of libexec applications in /usr/lib* and /usr/local/lib*
  /usr/{,local/}lib*/{,**/}* Pixr,

# Allow exec of software-center scripts. We may need to allow wider
  # permissions for /usr/share, but for now just do this. (LP: #972367)
  /usr/share/software-center/* Pixr,

# Allow exec of texlive font build scripts (LP: #1010909)
  /usr/share/texlive/texmf{,-dist}/web2c/{,**/}* Pixr,

# While the chromium and chrome sandboxes are setuid root, they only link
  # in limited libraries so glibc's secure execution should be enough to not
  # require the santized_helper (ie, LD_PRELOAD will only use standard system
  # paths (man ld.so)).
  /usr/lib/chromium-browser/chromium-browser-sandbox PUxr,
  /usr/lib/chromium{,-browser}/chrome-sandbox PUxr,
  /opt/google/chrome{,-beta,-unstable}/chrome-sandbox PUxr,
  /opt/google/chrome{,-beta,-unstable}/google-chrome Pixr,
  /opt/google/chrome{,-beta,-unstable}/chrome Pixr,
  /opt/google/chrome{,-beta,-unstable}/{,**/}lib*.so{,.*} m,

# Full access
  / r,
  /** rwkl,
  /{,usr/,usr/local/}lib{,32,64}/{,**/}*.so{,.*} m,

# Dangerous files
  audit deny owner /**/* m,              # compiled libraries
  audit deny owner /**/*.py* r,          # python imports
}

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