From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fgwmail8.fujitsu.co.jp (fgwmail8.fujitsu.co.jp [192.51.44.38]) by ozlabs.org (Postfix) with ESMTP id 4310AB7D15 for ; Mon, 8 Feb 2010 16:35:31 +1100 (EST) Received: from fgwmail5.fujitsu.co.jp (fgwmail5.fujitsu.co.jp [192.51.44.35]) by fgwmail8.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o18565eZ026567 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Mon, 8 Feb 2010 14:06:05 +0900 Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o18563IP013041 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Mon, 8 Feb 2010 14:06:03 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id 3132C45DE52 for ; Mon, 8 Feb 2010 14:06:03 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id F0C9A45DE4F for ; Mon, 8 Feb 2010 14:06:02 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id D9284E38006 for ; Mon, 8 Feb 2010 14:06:02 +0900 (JST) Received: from m108.s.css.fujitsu.com (m108.s.css.fujitsu.com [10.249.87.108]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 88EAF1DB8040 for ; Mon, 8 Feb 2010 14:06:02 +0900 (JST) From: KOSAKI Motohiro To: Michael Neuling Subject: Re: [PATCH] Restrict stack space reservation to rlimit 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" Date: Mon, 8 Feb 2010 14:06:01 +0900 (JST) Cc: stable@kernel.org, aeb@cwi.nl, James Morris , miltonm@bga.com, Oleg Nesterov , linuxppc-dev@ozlabs.org, Paul Mackerras , Alexander Viro , kosaki.motohiro@jp.fujitsu.com, WANG Cong , linux-fsdevel@vger.kernel.org, Serge Hallyn , Andrew Morton , Linus Torvalds , Ingo Molnar , linux-kernel@vger.kernel.org, Anton Blanchard List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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