From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753673Ab0AaPvW (ORCPT ); Sun, 31 Jan 2010 10:51:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753173Ab0AaPvV (ORCPT ); Sun, 31 Jan 2010 10:51:21 -0500 Received: from mx1.redhat.com ([209.132.183.28]:1025 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753136Ab0AaPvV (ORCPT ); Sun, 31 Jan 2010 10:51:21 -0500 Date: Sun, 31 Jan 2010 16:50:01 +0100 From: Oleg Nesterov To: Neil Horman Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, jmoskovc@redhat.com, mingo@redhat.com, drbd-dev@lists.linbit.com, benh@kernel.crashing.org, t.sailer@alumni.ethz.ch, abelay@mit.edu, gregkh@suse.de, spock@gentoo.org, viro@zeniv.linux.org.uk, neilb@suse.de, mfasheh@suse.com, menage@google.com, shemminger@linux-foundation.org, takedakn@nttdata.co.jp Subject: Re: [PATCH 2/2] exec: allow core_pipe recursion check to look for a value of 1 rather than 0 (v2) Message-ID: <20100131155000.GB13402@redhat.com> References: <20100121200806.GA29801@shamino.rdu.redhat.com> <20100129151024.GA19249@hmsreliant.think-freely.org> <20100129151458.GC19249@hmsreliant.think-freely.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100129151458.GC19249@hmsreliant.think-freely.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/29, Neil Horman wrote: > > void do_coredump(long signr, int exit_code, struct pt_regs *regs) > { > ... > - if (call_usermodehelper_pipe(helper_argv[0], helper_argv, NULL, > - &cprm.file)) { > + cprm.file = NULL; it is already NULL, > + if (call_usermodehelper_fns(helper_argv[0], helper_argv, NULL, > + UMH_WAIT_EXEC, umh_pipe_setup, > + NULL, &cprm)) { > + if (cprm.file) > + filp_close(cprm.file, NULL); Hmm. Looks like this change fixes the bug by accident. Before this patch, I think we leak info->stdin if kernel_thread() fails in __call_usermodehelper() pathes. Completely off-topic, but I think __call_usermodehelper(UMH_NO_WAIT) is buggy. if kernel_thread() failes it should do call_usermodehelper_freeinfo(). Also, UMH_WAIT_EXEC should set ->retval in this case. Cough. And why call_usermodehelper_exec() has this strange ->path[0] == '\0' check? Oleg.