From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262406AbTEKH4L (ORCPT ); Sun, 11 May 2003 03:56:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262416AbTEKH4L (ORCPT ); Sun, 11 May 2003 03:56:11 -0400 Received: from zero.aec.at ([193.170.194.10]:17925 "EHLO zero.aec.at") by vger.kernel.org with ESMTP id S262406AbTEKH4J (ORCPT ); Sun, 11 May 2003 03:56:09 -0400 Date: Sun, 11 May 2003 10:08:41 +0200 From: Andi Kleen To: akpm@digeo.com Cc: linux-kernel@vger.kernel.org Subject: [PATCH] Use correct page protection for put_dirty_page Message-ID: <20030511080841.GA31266@averell> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org put_page_dirty must use the page protection of the stack VMA, not hardcoded PAGE_COPY. They can be different e.g. when the stack is set non executable via VM_STACK_FLAGS. I added an fallback path for now because I'm not sure if the stack VMA is always predowngrowed here, if the printk better it may be also needed to add an stack extension here. -Andi --- linux-2.5.69-amd64/fs/exec.c-o 2003-04-20 21:21:50.000000000 +0200 +++ linux-2.5.69-amd64/fs/exec.c 2003-05-11 08:38:35.000000000 +0200 @@ -292,7 +292,9 @@ pgd_t * pgd; pmd_t * pmd; pte_t * pte; + pgprot_t prot; struct pte_chain *pte_chain; + struct vm_area_struct *vma; if (page_count(page) != 1) printk(KERN_ERR "mem_map disagrees with %p at %08lx\n", page, address); @@ -314,7 +316,13 @@ } lru_cache_add_active(page); flush_dcache_page(page); - set_pte(pte, pte_mkdirty(pte_mkwrite(mk_pte(page, PAGE_COPY)))); + vma = find_vma(tsk->mm, address); + if (!vma) { + printk("put_dirty_page: stack vma not extended yet %lx?\n",address); + prot = PAGE_COPY; + } else + prot = vma->vm_page_prot; + set_pte(pte, pte_mkdirty(pte_mkwrite(mk_pte(page, prot)))); pte_chain = page_add_rmap(page, pte, pte_chain); pte_unmap(pte); tsk->mm->rss++;