From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 031988D0040 for ; Fri, 1 Apr 2011 21:29:50 -0400 (EDT) Date: Fri, 1 Apr 2011 21:29:09 -0400 From: Stephen Wilson Subject: Re: [PATCH v3 2.6.39-rc1-tip 6/26] 6: Uprobes: register/unregister probes. Message-ID: <20110402012909.GA2779@fibrous.localdomain> References: <20110401143223.15455.19844.sendpatchset@localhost6.localdomain6> <20110401143338.15455.98645.sendpatchset@localhost6.localdomain6> <20110402002633.GA13277@fibrous.localdomain> <20110402005353.GA17416@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110402005353.GA17416@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Srikar Dronamraju Cc: Peter Zijlstra , Ingo Molnar , Steven Rostedt , Linux-mm , Arnaldo Carvalho de Melo , Linus Torvalds , Jonathan Corbet , Christoph Hellwig , Masami Hiramatsu , Thomas Gleixner , Ananth N Mavinakayanahalli , Oleg Nesterov , Andrew Morton , SystemTap , Jim Keniston , Roland McGrath , Andi Kleen , LKML On Sat, Apr 02, 2011 at 06:23:53AM +0530, Srikar Dronamraju wrote: > > > + > > > + mm = vma->vm_mm; > > > + if (!valid_vma(vma)) { > > > + mmput(mm); > > > + continue; > > > + } > > > + > > > + vaddr = vma->vm_start + offset; > > > + vaddr -= vma->vm_pgoff << PAGE_SHIFT; > > > > What happens here when someone passes an offset that is out of bounds > > for the vma? Looks like we could oops when the kernel tries to set a > > breakpoint. Perhaps check wrt ->vm_end? > > > > If the offset is wrong, install_uprobe will fail, since > grab_cache_page() should not be able to find that page for us. > And hence we return gracefully. Hummm. But grab_cache_page() just wraps find_or_create_page(), so I don't think it will do what you want. > I will surely test this case and I am happy to add a check for > vm_end. Thanks! -- steve -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org