From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,T_DKIM_INVALID, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8EE7BC3279B for ; Sat, 7 Jul 2018 00:14:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C6CF22AC6 for ; Sat, 7 Jul 2018 00:14:44 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VNA96Wzi" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1C6CF22AC6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932496AbeGGAOk (ORCPT ); Fri, 6 Jul 2018 20:14:40 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:35788 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753450AbeGGAOi (ORCPT ); Fri, 6 Jul 2018 20:14:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=KfdH+p09hrv53dPJnVsiVYUBTEnikxanFI+6z4VZa4g=; b=VNA96WziN/K9WPe5y/HQ9NcuB +XzDQyFd2UwOK9JS2g/9x8kaq5DNXT7pvaFRlXfwG1pY4wixGNzfNluL36VbrFRSAd6L0wS5JjsTB kJMgxFjN7mFSEfVXEnaDBro5u8d+jZ7+pEfN6uDxmbwtFPXUZb9aI/ST0OkYJym/a4dJDi+X6ztCt veerNfXQZTRMY074/lg9SpxHH9iiDQuUE9EfjpLMyK1TVI2aBmzmGZVGkWVJKH0X8cCqZTaGzaj6d q31f5sOMhjgiTsR3Jam26NO3O9CxM7fXa35EGtnHFz0EufrX1UQQln1QkAlNXR1ArS+cf1rmW6OS2 UT32GeH0g==; Received: from willy by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1fbas0-0001sD-EH; Sat, 07 Jul 2018 00:14:36 +0000 Date: Fri, 6 Jul 2018 17:14:36 -0700 From: Matthew Wilcox To: Andrew Morton Cc: Mark Rutland , linux-kernel@vger.kernel.org, Matthew Wilcox , valdis.kletnieks@vt.edu Subject: Re: [PATCH] radix-tree: avoid NULL dereference Message-ID: <20180707001436.GA31699@bombadil.infradead.org> References: <20180706134144.48446-1-mark.rutland@arm.com> <20180706142540.GB20816@bombadil.infradead.org> <20180706143603.xrjt4wn5pkuy25sf@lakrids.cambridge.arm.com> <20180706153640.53ot2cqm3varx7td@lakrids.cambridge.arm.com> <20180706144534.be6de0d9222e9755a3a09a2e@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180706144534.be6de0d9222e9755a3a09a2e@linux-foundation.org> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 06, 2018 at 02:45:34PM -0700, Andrew Morton wrote: > On Fri, 6 Jul 2018 16:36:41 +0100 Mark Rutland wrote: > > > > > > > > > Acked-by: Matthew Wilcox > > > > > > Cheers! > > > > > > I assume that Andrew will pick this up, if he's also happy with it. > > > > I've just started fuzzing, and found this also applies with > > node_tag_set(). I'll spin a v2 with that fixed up, too. > > Thanks. Please also give some thought to whether the fix should be > backported and if so, which patch(es) it Fixes:. I would say this goes all the way back to 0a835c4f090 ("Reimplement IDR and IDA using the radix tree") I don't know if it's worth backporting though. If the compiler does the normal optimisation, nobody will hit it. If it doesn't, the first use of an IDR will trip the bug. So it's not like a user-exploitable bug.