[PATCH v2 07/12] ptrace: Don't change __state

[Sebastian Andrzej Siewior]

On 2022-04-29 16:48:32 [-0500], Eric W. Biederman wrote:
> Stop playing with tsk->__state to remove TASK_WAKEKILL while a ptrace
> command is executing.
> 
> Instead TASK_WAKEKILL from the definition of TASK_TRACED, and
> implemention a new jobctl flag TASK_PTRACE_FROZEN.  This new This new

Instead adding TASK_WAKEKILL to the definition of TASK_TRACED, implement
a new jobctl flag TASK_PTRACE_FROZEN for this. This new

> flag is set in jobctl_freeze_task and cleared when ptrace_stop is
> awoken or in jobctl_unfreeze_task (when ptrace_stop remains asleep).
> 
> In singal_wake_up add __TASK_TRACED to state along with TASK_WAKEKILL
     signal_wake_up

> when it is indicated a fatal signal is pending.  Skip adding
                      +that ?

> __TASK_TRACED when TASK_PTRACE_FROZEN is not set.  This has the same
> effect as changing TASK_TRACED to __TASK_TRACED as all of the wake_ups
                                                                        ,
> that use TASK_KILLABLE go through signal_wake_up.
                        ,

> Don't set TASK_TRACED if fatal_signal_pending so that the code
> continues not to sleep if there was a pending fatal signal before
> ptrace_stop is called.  With TASK_WAKEKILL no longer present in
> TASK_TRACED signal_pending_state will no longer prevent ptrace_stop
> from sleeping if there is a pending fatal signal.
> 
> Previously the __state value of __TASK_TRACED was changed to
> TASK_RUNNING when woken up or back to TASK_TRACED when the code was
> left in ptrace_stop.  Now when woken up ptrace_stop now clears
> JOBCTL_PTRACE_FROZEN and when left sleeping ptrace_unfreezed_traced
> clears JOBCTL_PTRACE_FROZEN.
> 
> Signed-off-by: "Eric W. Biederman" <ebiederm at xmission.com>

Sebastian