Messages in this thread |  | | | Date | Wed, 29 Apr 2009 00:30:25 +0200 | | From | Oleg Nesterov <> | | Subject | Q: selinux_bprm_committed_creds() && signals/do_wait |
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selinux_bprm_committed_creds:
rc = avc_has_perm() if (rc) { flush_signals(current); This doesn't look right. If the task was SIGKILL'ed we must not proceed, the task should die. The fix is simple, we should check SIGNAL_GROUP_EXIT and do nothing in this case, the task will exit before return to user space. If SIGNAL_GROUP_EXIT is set, it is just wrong to drop SIGKILL and continue.
But, before fixing, I'd like to understand why we are doing
flush_signal_handlers(current, 1); sigemptyset(¤t->blocked);
later. Could someone explain ? This looks unneeded.
Another question,
wake_up_interruptible(¤t->parent->signal->wait_chldexit);
Shouldn't we use ->real_parent ? Afaics, we shouldn't worry about the tracer if current is ptraced, exec must not succeed if the tracer has no rights to trace this task after cred changing. But we should notify ->real_parent which is, well, real parent.
Also, we don't need _irq to take tasklist_lock, and we don't actually need ->siglock.
Oleg.
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