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=-7.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=no 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 56507C433E2 for ; Mon, 7 Sep 2020 22:51:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F001F216C4 for ; Mon, 7 Sep 2020 22:51:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599519115; bh=qow4/cZPIqfrydocDClnY9AoIUGhX2rllTat0rDAaeg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=vOny1jmZSHOYYRmHbDShuIRVX5kQgb9q99MZyocv9OOuy/3IQ2w3jsoV++NOkiRUD d3QBnrafALD9aaHIVjz5sOxLrgMMwaG9U7nhnG7gfeL0yCus2J4EktLKp1AWZB1fMS XhLw79w/xYmfR5Yb/2uugaqaZVLcOcEjuGZdE8FM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728101AbgIGWvy (ORCPT ); Mon, 7 Sep 2020 18:51:54 -0400 Received: from mail.kernel.org ([198.145.29.99]:58304 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727771AbgIGWvx (ORCPT ); Mon, 7 Sep 2020 18:51:53 -0400 Received: from sol.localdomain (172-10-235-113.lightspeed.sntcca.sbcglobal.net [172.10.235.113]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 0668121473; Mon, 7 Sep 2020 22:51:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599519113; bh=qow4/cZPIqfrydocDClnY9AoIUGhX2rllTat0rDAaeg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VMDxdMzHhBsVlSMiqfcgphgXB/aBL8oWR+gBy2nsz7elAn3eb9rn86M3fyvxGq3Hx r6jGw228WE0dnRO/KhzV+TJ7xT6kNwgWN5SF2Xs7ClBxQTRrwS600O4a9dbM3xh3mt t8En8ZEdJ06qQUfC7HHGwv5VzTEptet+nRRy0h4w= Date: Mon, 7 Sep 2020 15:51:51 -0700 From: Eric Biggers To: linux-fscrypt@vger.kernel.org Cc: linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Jeff Layton , Paul Crowley Subject: Re: [PATCH] fscrypt: restrict IV_INO_LBLK_32 to ino_bits <= 32 Message-ID: <20200907225151.GC68127@sol.localdomain> References: <20200824203841.1707847-1-ebiggers@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200824203841.1707847-1-ebiggers@kernel.org> Sender: linux-fscrypt-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org On Mon, Aug 24, 2020 at 01:38:41PM -0700, Eric Biggers wrote: > From: Eric Biggers > > When an encryption policy has the IV_INO_LBLK_32 flag set, the IV > generation method involves hashing the inode number. This is different > from fscrypt's other IV generation methods, where the inode number is > either not used at all or is included directly in the IVs. > > Therefore, in principle IV_INO_LBLK_32 can work with any length inode > number. However, currently fscrypt gets the inode number from > inode::i_ino, which is 'unsigned long'. So currently the implementation > limit is actually 32 bits (like IV_INO_LBLK_64), since longer inode > numbers will have been truncated by the VFS on 32-bit platforms. > > Fix fscrypt_supported_v2_policy() to enforce the correct limit. > > This doesn't actually matter currently, since only ext4 and f2fs support > IV_INO_LBLK_32, and they both only support 32-bit inode numbers. But we > might as well fix it in case it matters in the future. > > Ideally inode::i_ino would instead be made 64-bit, but for now it's not > needed. (Note, this limit does *not* prevent filesystems with 64-bit > inode numbers from adding fscrypt support, since IV_INO_LBLK_* support > is optional and is useful only on certain hardware.) > > Fixes: e3b1078bedd3 ("fscrypt: add support for IV_INO_LBLK_32 policies") > Reported-by: Jeff Layton > Signed-off-by: Eric Biggers Applied to fscrypt.git#master for 5.10. - Eric