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=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 CCA24C4363D for ; Fri, 2 Oct 2020 08:53:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9492B206DC for ; Fri, 2 Oct 2020 08:53:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="kjt52rX2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726090AbgJBIxZ (ORCPT ); Fri, 2 Oct 2020 04:53:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725993AbgJBIxZ (ORCPT ); Fri, 2 Oct 2020 04:53:25 -0400 Received: from mail-pj1-x1044.google.com (mail-pj1-x1044.google.com [IPv6:2607:f8b0:4864:20::1044]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05F4DC0613D0 for ; Fri, 2 Oct 2020 01:53:25 -0700 (PDT) Received: by mail-pj1-x1044.google.com with SMTP id t23so428611pji.0 for ; Fri, 02 Oct 2020 01:53:25 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=XQF3jv1mnrYoDXvVuOir5WOLXN3C0c3UPYNpgx0sfbk=; b=kjt52rX2aP/WC0rMb3XagTaFN2vDD5GrTl4yH0jEu5B+gzZaZp2X2FWgSxn9rv3ZSt o4Tvcdyfe99UJWtHWLMKxX9tm9pjKMbXsxfAoKlhlDN8Ui30JePMiPYWGu6cPIMDTMnj k49BQ3tlKm5hP6ZhkDdVMWiAFID0wtMbn4jTsdqdsJS8QkaxuyQz5/e7RPL2OxIRgUyK pvuw0ng1lFMXifT7MUk0BpVTgRLCOCEpKJC5SuhmIMMV7J/uvN41em3P9YUppv/Is4hF ULY9CajPnz/fPGB3m02KoI3R9clWTCf+SoFuLrvYxwbNudlRMU5hOeqHGgWYudZ9kMo1 GZ9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=XQF3jv1mnrYoDXvVuOir5WOLXN3C0c3UPYNpgx0sfbk=; b=VPuXhPaiHju3VBH/kQowjIIXHHYaghPZ8MtUfkN6RT72XBsxRfykePZQbboOAFeZdp fm7aG8nIl3eBtw4o/Pnd27Ojyvf5JoVVqBeOfG5vyqGimhKIfn+NKjPLtLbcbF6d51nF 6bUI72s1NAacAbxVK/4pt7Jivoz02J+mMW9Wa8d2tQ6j3GvssppkXeH4Pqv3t3+P81wn dgj+wKpr/FgQsB/GYZu2wHRSLHQhe+7SYVB4Ak6iHD2zhT7O6IJIbSBVcfUE82Ci94s4 5WU3nvvuHpY2SO4mIKg5ID1pkxVW7uWF+ulCq52fCKZYXhfRwVLF+09eKMDXwFZxUVgK X04g== X-Gm-Message-State: AOAM530boh1EaHuR3imgI1uUJSkZelS5jSbFavewVMUnPxCBX1HqNJQl 6KKK13sNkkvoO6Vzi1c621M= X-Google-Smtp-Source: ABdhPJxG6q1weCaf4mFQbmCL6RbSSGqPGUBBKEa+FoazG/R1Mes1gYj6BSJfY1zWLyAkdtJLIhAdGA== X-Received: by 2002:a17:90a:db49:: with SMTP id u9mr1676275pjx.119.1601628804629; Fri, 02 Oct 2020 01:53:24 -0700 (PDT) Received: from garuda.localnet ([122.172.184.91]) by smtp.gmail.com with ESMTPSA id 84sm1127628pfw.14.2020.10.02.01.53.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 02 Oct 2020 01:53:24 -0700 (PDT) From: Chandan Babu R To: "Darrick J. Wong" Cc: linux-xfs@vger.kernel.org Subject: Re: [PATCH 1/2] xfs: limit entries returned when counting fsmap records Date: Fri, 02 Oct 2020 14:21:10 +0530 Message-ID: <4857521.XMzPl6tNdl@garuda> In-Reply-To: <160161416467.1967459.10753396346204946090.stgit@magnolia> References: <160161415855.1967459.13623226657245838117.stgit@magnolia> <160161416467.1967459.10753396346204946090.stgit@magnolia> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Friday 2 October 2020 10:19:24 AM IST Darrick J. Wong wrote: > From: Darrick J. Wong > > If userspace asked fsmap to count the number of entries, we cannot > return more than UINT_MAX entries because fmh_entries is u32. > Therefore, stop counting if we hit this limit or else we will waste time > to return truncated results. > > Fixes: e89c041338ed ("xfs: implement the GETFSMAP ioctl") > Signed-off-by: Darrick J. Wong The upper bound check is correct. Reviewed-by: Chandan Babu R > --- > fs/xfs/xfs_fsmap.c | 3 +++ > 1 file changed, 3 insertions(+) > > > diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c > index 4eebcec4aae6..aa36e7daf82c 100644 > --- a/fs/xfs/xfs_fsmap.c > +++ b/fs/xfs/xfs_fsmap.c > @@ -256,6 +256,9 @@ xfs_getfsmap_helper( > > /* Are we just counting mappings? */ > if (info->head->fmh_count == 0) { > + if (info->head->fmh_entries == UINT_MAX) > + return -ECANCELED; > + > if (rec_daddr > info->next_daddr) > info->head->fmh_entries++; > > > -- chandan