• Oleg Nesterov's avatar
    exec: rework the group exit and fix the race with kill · ed5d2cac
    Oleg Nesterov authored
    As Roland pointed out, we have the very old problem with exec.  de_thread()
    sets SIGNAL_GROUP_EXIT, kills other threads, changes ->group_leader and then
    clears signal->flags.  All signals (even fatal ones) sent in this window
    (which is not too small) will be lost.
    
    With this patch exec doesn't abuse SIGNAL_GROUP_EXIT.  signal_group_exit(),
    the new helper, should be used to detect exit_group() or exec() in progress.
    It can have more users, but this patch does only strictly necessary changes.
    Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
    Cc: Davide Libenzi <davidel@xmailserver.org>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Robin Holt <holt@sgi.com>
    Cc: Roland McGrath <roland@redhat.com>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
    ed5d2cac
exit.c 44.4 KB