ptrace: wait_task_zombie: do not account traced sub-threads

The bug is ancient.

If we trace the sub-thread of our natural child and this sub-thread exits,
we update parent->signal->cxxx fields.  But we should not do this until
the whole thread-group exits, otherwise we account this thread (and all
other live threads) twice.

Add the task_detached() check.  No need to check thread_group_empty(),
wait_consider_task()->delay_group_leader() already did this.

Signed-off-by: Oleg Nesterov <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Acked-by: Roland McGrath <[email protected]>
Cc: Stanislaw Gruszka <[email protected]>
Cc: Vitaly Mayatskikh <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions