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=-5.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, 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 8F926C43387 for ; Mon, 14 Jan 2019 18:47:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 58A9A20645 for ; Mon, 14 Jan 2019 18:47:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Z0zvzzg1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726804AbfANSro (ORCPT ); Mon, 14 Jan 2019 13:47:44 -0500 Received: from mail-lj1-f174.google.com ([209.85.208.174]:38937 "EHLO mail-lj1-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726745AbfANSro (ORCPT ); Mon, 14 Jan 2019 13:47:44 -0500 Received: by mail-lj1-f174.google.com with SMTP id t9-v6so48177ljh.6 for ; Mon, 14 Jan 2019 10:47:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:mime-version:content-disposition :user-agent; bh=dThSdtJskhfxCKpEStbcjO4U+BnLsz/sqiq0gz9PYL0=; b=Z0zvzzg1SwHpBlWMM2Tc4LylgEVrl7QocyTlvbI9rjQlSP2QwireydmetU3F//D9OV IySzf8fOP3YxG6z9lp/M+Ta1sDYYMDqiJGnIM5pljPoNIAJIXEDlYTo6jYcwpK8baItX h1CfSdjAYUjH9nyx6+gFCwPp9SBniNNZZwnVclcK1Miao+HxJThnbo/DDbPVUiv0J97Y iRzroJXDcBkYzHBjq2lPga4GVB0GTWMRy4doiYkS6sexoeWQhGDThJv71Oe8tk44N0ms IIYSxQUH8hFu7at9fa7BwPX9ewapiEgm+yK/XETcsI/Jl8O6Oud1SRO593XB7uJnFYUh gWaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:mime-version :content-disposition:user-agent; bh=dThSdtJskhfxCKpEStbcjO4U+BnLsz/sqiq0gz9PYL0=; b=nEIIW0gllaaONQ43sdbHGHwDYXU3XIsHCC/irDraYGig3HK68V592/F9NThmpQtcA1 bD5RIbOwLOf5ZdE4CheYkAvOhjw1KrE4AwGK+Ej2Gd3SUWbPX1lR5NlOVnCNuZtyVhQx mo6TV9JMKL2rV8YOTGiADNsuXY6LUEjHKkaqzwbSV5GSGg836f4sKNf7qq84oMjB1tGU RNwHQTupd7Q89b6czEH4bNuZZre37Hz9SC/U/6vE/EUvzSxEuXLCAxC57TMtFccVoMob 7KaTOjKVc/8CFIIT1r9ofDcS11RNE0UOJpF/9VaCVVwTmRBbcgmTHcufz1lpAytpwPN/ 5OrQ== X-Gm-Message-State: AJcUukcWvXOILWuDNLG99sY0Q0ZE0WzsQlGoNnQGr/k4bshPK15RWgge 6dcZa7nZ+Zc4zLJCAhtVyUi98BF0 X-Google-Smtp-Source: ALg8bN7/H3LFJXogcN/XzDKaIuEufLLTfNMwBjS3FAWWJegipFJx0Cx2NQu7ZEIPWAp1q+A1ZjfRiA== X-Received: by 2002:a2e:a0d3:: with SMTP id f19-v6mr15174967ljm.48.1547491662381; Mon, 14 Jan 2019 10:47:42 -0800 (PST) Received: from uranus.localdomain ([5.18.103.226]) by smtp.gmail.com with ESMTPSA id h3sm214702lfb.49.2019.01.14.10.47.41 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 14 Jan 2019 10:47:41 -0800 (PST) Received: by uranus.localdomain (Postfix, from userid 1000) id 4EEF44608DD; Mon, 14 Jan 2019 21:47:41 +0300 (MSK) Date: Mon, 14 Jan 2019 21:47:41 +0300 From: Cyrill Gorcunov To: Matthew Wilcox Cc: LKML Subject: [PATCH]: xarray: Fix potential out of bounds access Message-ID: <20190114184741.GF17906@uranus.lan> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since the mark is used as an array index we should use preincrement to not access the XA_MARK_MAX index. Cc: Matthew Wilcox Signed-off-by: Cyrill Gorcunov --- Matthew, take a look please, I suspect we may access the mark index out of allocated one. Compile tested only. It comes from 58d6ea3085f2e53714810a513c61629f6d2be0a6 lib/xarray.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: linux-next.git/lib/xarray.c =================================================================== --- linux-next.git.orig/lib/xarray.c +++ linux-next.git/lib/xarray.c @@ -129,7 +129,7 @@ static void xas_squash_marks(const struc continue; __set_bit(xas->xa_offset, marks); bitmap_clear(marks, xas->xa_offset + 1, xas->xa_sibs); - } while (mark++ != (__force unsigned)XA_MARK_MAX); + } while (++mark != (__force unsigned)XA_MARK_MAX); } /* extracts the offset within this node from the index */