From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752525Ab2GHVSZ (ORCPT ); Sun, 8 Jul 2012 17:18:25 -0400 Received: from perches-mx.perches.com ([206.117.179.246]:46998 "EHLO labridge.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752431Ab2GHVSY (ORCPT ); Sun, 8 Jul 2012 17:18:24 -0400 Message-ID: <1341782304.13174.21.camel@joe2Laptop> Subject: Re: [PATCH 3/5] uprobes: fix overflow in vma_address/find_active_uprobe From: Joe Perches To: Oleg Nesterov Cc: Ingo Molnar , Srikar Dronamraju , Ananth N Mavinakayanahalli , Anton Arapov , Peter Zijlstra , linux-kernel@vger.kernel.org Date: Sun, 08 Jul 2012 14:18:24 -0700 In-Reply-To: <20120708203006.GA18233@redhat.com> References: <20120708203006.GA18233@redhat.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.2- Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2012-07-08 at 22:30 +0200, Oleg Nesterov wrote: > vma->vm_pgoff is "unsigned long", it should be promoted to loff_t > before the multiplication to avoid the overflow. [] > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c [] > @@ -117,7 +117,7 @@ static loff_t vma_address(struct vm_area_struct *vma, loff_t offset) > loff_t vaddr; > > vaddr = vma->vm_start + offset; > - vaddr -= vma->vm_pgoff << PAGE_SHIFT; > + vaddr -= (loff_t)vma->vm_pgoff << PAGE_SHIFT; > > return vaddr; > } > @@ -1450,7 +1450,7 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp) > > inode = vma->vm_file->f_mapping->host; > offset = bp_vaddr - vma->vm_start; > - offset += (vma->vm_pgoff << PAGE_SHIFT); > + offset += ((loff_t)vma->vm_pgoff << PAGE_SHIFT); It's be nice to take remove the unnecessary parenthesis and make it consistent with the vaddr use above it too.