Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751359Ab0BHFGL (ORCPT ); Mon, 8 Feb 2010 00:06:11 -0500 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:34680 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750981Ab0BHFGI (ORCPT ); Mon, 8 Feb 2010 00:06:08 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Michael Neuling Subject: Re: [PATCH] Restrict stack space reservation to rlimit Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton , Linus Torvalds , Alexander Viro , Oleg Nesterov , James Morris , Ingo Molnar , linux-fsdevel@vger.kernel.org, Anton Blanchard , stable@kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Serge Hallyn , WANG Cong , Paul Mackerras , benh@kernel.crashing.org, miltonm@bga.com, aeb@cwi.nl In-Reply-To: <18033.1265587672@neuling.org> References: <10125.1265451732@neuling.org> <18033.1265587672@neuling.org> Message-Id: <20100208140323.FB52.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Mon, 8 Feb 2010 14:06:01 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2270 Lines: 73 Hi > apkm, linus: this or something like it needs to go into 2.6.33 (& 32) to > fix 'ulimit -s'. "fix ulimit -s" is too cool explanation ;-) we are not ESPer. please consider to provide what bug is exist. > Mikey > > [PATCH] Restrict stack space reservation to rlimit > > When reserving stack space for a new process, make sure we're not > attempting to allocate more than rlimit allows. > > Also, reserve the same stack size independent of page size. Why do we need page size independent stack size? It seems to have compatibility breaking risk. > > This fixes a bug unmasked by fc63cf237078c86214abcb2ee9926d8ad289da9b > > Signed-off-by: Michael Neuling > Cc: Anton Blanchard > Cc: stable@kernel.org > --- > fs/exec.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > Index: clone1/fs/exec.c > =================================================================== > --- clone1.orig/fs/exec.c > +++ clone1/fs/exec.c > @@ -554,7 +554,7 @@ static int shift_arg_pages(struct vm_are > return 0; > } > > -#define EXTRA_STACK_VM_PAGES 20 /* random */ > +#define EXTRA_STACK_VM_SIZE 81920UL /* randomly 20 4K pages */ > > /* > * Finalizes the stack vm_area_struct. The flags and permissions are updated, > @@ -627,10 +627,13 @@ int setup_arg_pages(struct linux_binprm > goto out_unlock; > } > > + stack_base = min(EXTRA_STACK_VM_SIZE, > + current->signal->rlim[RLIMIT_STACK].rlim_cur) - > + PAGE_SIZE; > #ifdef CONFIG_STACK_GROWSUP > - stack_base = vma->vm_end + EXTRA_STACK_VM_PAGES * PAGE_SIZE; > + stack_base = vma->vm_end + stack_base; > #else > - stack_base = vma->vm_start - EXTRA_STACK_VM_PAGES * PAGE_SIZE; > + stack_base = vma->vm_start - stack_base; > #endif > ret = expand_stack(vma, stack_base); > if (ret) > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/