From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756283Ab2DQPrX (ORCPT ); Tue, 17 Apr 2012 11:47:23 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51836 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756173Ab2DQPrV (ORCPT ); Tue, 17 Apr 2012 11:47:21 -0400 From: Doug Ledford To: linux-kernel@vger.kernel.org Cc: akpm@linux-foundation.org, kosaki.motohiro@gmail.com, KOSAKI Motohiro , Amerigo Wang , "Serge E. Hallyn" , Jiri Slaby Subject: [Patch 5/8] mqueue: revert bump up DFLT_*MAX Date: Tue, 17 Apr 2012 11:46:22 -0400 Message-Id: In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: KOSAKI Motohiro Mqueue limitation is slightly naieve parameter likes other ipcs because unprivileged user can consume kernel memory by using ipcs. Thus, too aggressive raise bring us security issue. Example, current setting allow evil unprivileged user use 256GB (= 256 * 1024 * 1024*1024) and it's enough large to system will belome unresponsive. Don't do that. Instead, every admin should adjust the knobs for their own systems. Signed-off-by: KOSAKI Motohiro Acked-by: Doug Ledford Acked-by: Joe Korty Cc: Amerigo Wang Cc: Serge E. Hallyn Cc: Jiri Slaby --- include/linux/ipc_namespace.h | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/ipc_namespace.h b/include/linux/ipc_namespace.h index 6e1dd08..2488535 100644 --- a/include/linux/ipc_namespace.h +++ b/include/linux/ipc_namespace.h @@ -118,12 +118,12 @@ extern int mq_init_ns(struct ipc_namespace *ns); #define DFLT_QUEUESMAX 256 #define HARD_QUEUESMAX 1024 #define MIN_MSGMAX 1 -#define DFLT_MSG 64U -#define DFLT_MSGMAX 1024 +#define DFLT_MSG 10U +#define DFLT_MSGMAX 10 #define HARD_MSGMAX 65536 #define MIN_MSGSIZEMAX 128 #define DFLT_MSGSIZE 8192U -#define DFLT_MSGSIZEMAX (1024*1024) +#define DFLT_MSGSIZEMAX 8192 #define HARD_MSGSIZEMAX (16*1024*1024) #else static inline int mq_init_ns(struct ipc_namespace *ns) { return 0; } -- 1.7.7.6