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["Stephen M. Webb" <stephen.webb@xxxxxxxxxxxxx>]

** Changed in: unity (Ubuntu Trusty)
       Status: New => In Progress

** Changed in: unity (Ubuntu)
   Importance: Undecided => Critical

** Changed in: unity (Ubuntu Trusty)
   Importance: Undecided => Critical

** Changed in: unity (Ubuntu Trusty)
     Assignee: (unassigned) => Stephen M. Webb (bregma)

** Description changed:

- I have a user reporting an incidence that trusty unity desktop got
- unlocked on its own:
+ [Impact]
  
- "In the morning, after coming to my desk, I just pressed the space bar
- on my desktop to get the monitors woken up. The monitors came up with
- the locked screen and then after a while it got unlocked to my
- surprise!"
+ Certain code paths may cause the Unity lockscreen to crash, which can
+ allow the screen to be unlocked without a password entry.
  
-    There was compiz crash file on his system at that time. However, I
- don't have the right debug symbols to which file (or function) it
- crashed into. Here is the top part of the stack trace when I ran apport-
- retrace -s  on his crash file:
+ [Test Case]
  
- ---------------------------------------------------------------------------------------------------------------
- --- stack trace ---
- #0  0x00007ff17ed06608 in ?? () from /usr/lib/x86_64-linux-gnu/gio/modules/libdconfsettings.so
- No symbol table info available.
- #1  0x00007ff17ed06cf3 in ?? () from /usr/lib/x86_64-linux-gnu/gio/modules/libdconfsettings.so
- No symbol table info available.
- #2  0x00007ff17ed04e2d in ?? () from /usr/lib/x86_64-linux-gnu/gio/modules/libdconfsettings.so
- No symbol table info available.
- #3  0x00007ff17f3fdd02 in g_settings_backend_read (backend=<optimized out>, key=key@entry=0xab011c0 "/org/gnome/desktop/lockdown/disable-lock-screen", expected_type=0x7ff1877135a0 <g_variant_type_info_basic_chars>, default_value=default_value@entry=0) at /build/buildd/glib2.0-2.40.2/./gio/gsettingsbackend.c:701
-         value = <optimized out>
- #4  0x00007ff17f401c7b in g_settings_read_from_backend (settings=settings@entry=0x7ff13800a570, key=key@entry=0x7fffdde9c920, user_value_only=user_value_only@entry=0, default_value=default_value@entry=0) at /build/buildd/glib2.0-2.40.2/./gio/gsettings.c:1052
-         value = <optimized out>
-         fixup = <optimized out>
-         path = 0xab011c0 "/org/gnome/desktop/lockdown/disable-lock-screen"
- #5  0x00007ff17f402e7a in g_settings_get_value (settings=0x7ff13800a570, key=0x2087618 "disable-lock-screen") at /build/buildd/glib2.0-2.40.2/./gio/gsettings.c:1092
-         skey = {schema = 0x7ff13c017a80, name = 0x4b2fa7c "disable-lock-screen", is_flags = 0, is_enum = 0, strinfo = 0x0, strinfo_length = 0, unparsed = 0x0, lc_char = 0 '\000', type = 0x7ff1877135a0 <g_variant_type_info_basic_chars>, minimum = 0x0, maximum = 0x0, default_value = 0xb9c5b30, ref_count = 0}
-         value = <optimized out>
-         __FUNCTION__ = "g_settings_get_value"
- -----------------------------------------------------------------------------------------------------------------
+ Unfortunately this bug only appears under certain race conditions and is
+ not reliably reproduce able.
  
-    The top part of the trash file when viewed in TextEdit has the information :
- -------------------------------------------------
- ProblemType: Crash
- Architecture: amd64
- CrashCounter: 1
- CurrentDesktop: Unity
- Date: Fri Dec 12 10:16:52 2014
- DistroRelease: Ubuntu 14.04
- ExecutablePath: /usr/bin/compiz
- ExecutableTimestamp: 1405349348
- ProcCmdline: compiz
- --------------------------------------------------
+ [Regression Potential]
  
-    His system is Ubuntu trusty 14.04.1 LTS. Unity installed
- 7.2.3+14.04.20140826-0ubuntu1.0.1 .
+ The change in the code simply assumes that if a screen is already
+ locked, then it is lockable this avoiding certain operations that are
+ inherently racy.  It is possible that this fix does not avoid all
+ possible crash conditions in the lockscreen and there may still be
+ unaccounted-for crashes in the lockscreen.
+ 
+ [Other Info]
+ 
+ This fix was cherry picked for Ubuntu 14.04 LTS from the Ubuntu "Vivid
+ Vervet" dev release where it has been in testing for some time.

-- 
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https://bugs.launchpad.net/bugs/1410582

Title:
  [Trusty / Unity] Desktop got unlocked on its own.

Status in Unity:
  Fix Released
Status in Unity 7.2 series:
  In Progress
Status in unity package in Ubuntu:
  Fix Released
Status in unity source package in Trusty:
  In Progress

Bug description:
  [Impact]

  Certain code paths may cause the Unity lockscreen to crash, which can
  allow the screen to be unlocked without a password entry.

  [Test Case]

  Unfortunately this bug only appears under certain race conditions and
  is not reliably reproduce able.

  [Regression Potential]

  The change in the code simply assumes that if a screen is already
  locked, then it is lockable this avoiding certain operations that are
  inherently racy.  It is possible that this fix does not avoid all
  possible crash conditions in the lockscreen and there may still be
  unaccounted-for crashes in the lockscreen.

  [Other Info]

  This fix was cherry picked for Ubuntu 14.04 LTS from the Ubuntu "Vivid
  Vervet" dev release where it has been in testing for some time.

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