linux-kernel - Re: [PATCH 1/2] copy_process: fix CLONE_PARENT && ->exit

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 25 Feb 2009 11:39:27 -0800 (PST)
From:	Roland McGrath <roland@...hat.com>
To:	Oleg Nesterov <oleg@...hat.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Alan Cox <alan@...rguk.ukuu.org.uk>,
	Chris Evans <scarybeasts@...il.com>,
	David Howells <dhowells@...hat.com>,
	Don Howard <dhoward@...hat.com>,
	Eugene Teo <eugene@...hat.com>,
	Michael Kerrisk <mtk.manpages@...glemail.com>,
	Tavis Ormandy <taviso@....lonestar.org>,
	Vitaly Mayatskikh <vmayatsk@...hat.com>, stable@...nel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] copy_process: fix CLONE_PARENT && ->exit_signal
	interaction

As I think I said before, I don't really know what the actual use case is
for CLONE_PARENT without CLONE_THREAD.  So it's easy to approve changing
its behavior, but I do vaguely worry about who expected what behavior before.

Just for readability, I would prefer that you just change the first line
above that sets p->exit_signal initially.  i.e. (but with some comments):

diff --git a/kernel/fork.c b/kernel/fork.c
index a66fbde..f56793b 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1184,7 +1184,10 @@ static struct task_struct *copy_process(unsigned long clone_flags,
 	p->parent_exec_id = p->self_exec_id;
 
 	/* ok, now we should be set up.. */
-	p->exit_signal = (clone_flags & CLONE_THREAD) ? -1 : (clone_flags & CSIGNAL);
+	p->exit_signal = ((clone_flags & CLONE_THREAD) ? -1 :
+			  (clone_flags & CLONE_PARENT) ?
+			  current->group_leader->exit_signal :
+			  (clone_flags & CSIGNAL));
 	p->pdeath_signal = 0;
 	p->exit_state = 0;
 


Thanks,
Roland
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/