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=-11.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 B63DCC2D0E2 for ; Tue, 22 Sep 2020 10:34:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4666B239A1 for ; Tue, 22 Sep 2020 10:34:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=gmx.net header.i=@gmx.net header.b="T/9c7fIk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726572AbgIVKea (ORCPT ); Tue, 22 Sep 2020 06:34:30 -0400 Received: from mout.gmx.net ([212.227.15.19]:33771 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726353AbgIVKe2 (ORCPT ); Tue, 22 Sep 2020 06:34:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1600770861; bh=gK0RFP6GyazagibZBvMt5lSyd7+MlIn9Rhol550SGmY=; h=X-UI-Sender-Class:Subject:To:References:From:Date:In-Reply-To; b=T/9c7fIkJ0p1eHSGmfmo0wd/421I1UE0ZoWIKPSTIE7RPW0xqu3HmnR5eCqVI/PYV L8czxMFgrBivQtZe3jU6qykjYEELXc2LxQOM3XZvABkBHvBCAxItNFTNa3m0QZUjec bAC/vkwf/q+gMIKLu7L5qXwGFffZS8A4huHwhTp8= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from [0.0.0.0] ([149.28.201.231]) by mail.gmx.com (mrgmx005 [212.227.17.184]) with ESMTPSA (Nemesis) id 1MIx3I-1k1MM30kyA-00KRH4; Tue, 22 Sep 2020 12:34:21 +0200 Subject: Re: [PATCH] btrfs: fix false alert caused by legacy btrfs root item To: Martin Steigerwald , linux-btrfs@vger.kernel.org, Qu Wenruo References: <20200922023701.32654-1-wqu@suse.com> <4591966.Q0mfgpEauH@merkaba> From: Qu Wenruo Autocrypt: addr=quwenruo.btrfs@gmx.com; prefer-encrypt=mutual; keydata= mQENBFnVga8BCACyhFP3ExcTIuB73jDIBA/vSoYcTyysFQzPvez64TUSCv1SgXEByR7fju3o 8RfaWuHCnkkea5luuTZMqfgTXrun2dqNVYDNOV6RIVrc4YuG20yhC1epnV55fJCThqij0MRL 1NxPKXIlEdHvN0Kov3CtWA+R1iNN0RCeVun7rmOrrjBK573aWC5sgP7YsBOLK79H3tmUtz6b 9Imuj0ZyEsa76Xg9PX9Hn2myKj1hfWGS+5og9Va4hrwQC8ipjXik6NKR5GDV+hOZkktU81G5 gkQtGB9jOAYRs86QG/b7PtIlbd3+pppT0gaS+wvwMs8cuNG+Pu6KO1oC4jgdseFLu7NpABEB AAG0IlF1IFdlbnJ1byA8cXV3ZW5ydW8uYnRyZnNAZ214LmNvbT6JAU4EEwEIADgCGwMFCwkI BwIGFQgJCgsCBBYCAwECHgECF4AWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1oQAKCRDC PZHzoSX+qCY6CACd+mWu3okGwRKXju6bou+7VkqCaHTdyXwWFTsr+/0ly5nUdDtT3yEVggPJ 3VP70wjlrxUjNjFb6iIvGYxiPOrop1NGwGYvQktgRhaIhALG6rPoSSAhGNjwGVRw0km0PlIN D29BTj/lYEk+jVM1YL0QLgAE1AI3krihg/lp/fQT53wLhR8YZIF8ETXbClQG1vJ0cllPuEEv efKxRyiTSjB+PsozSvYWhXsPeJ+KKjFen7ebE5reQTPFzSHctCdPnoR/4jSPlnTlnEvLeqcD ZTuKfQe1gWrPeevQzgCtgBF/WjIOeJs41klnYzC3DymuQlmFubss0jShLOW8eSOOWhLRuQEN BFnVga8BCACqU+th4Esy/c8BnvliFAjAfpzhI1wH76FD1MJPmAhA3DnX5JDORcgaCbPEwhLj 1xlwTgpeT+QfDmGJ5B5BlrrQFZVE1fChEjiJvyiSAO4yQPkrPVYTI7Xj34FnscPj/IrRUUka 68MlHxPtFnAHr25VIuOS41lmYKYNwPNLRz9Ik6DmeTG3WJO2BQRNvXA0pXrJH1fNGSsRb+pK EKHKtL1803x71zQxCwLh+zLP1iXHVM5j8gX9zqupigQR/Cel2XPS44zWcDW8r7B0q1eW4Jrv 0x19p4P923voqn+joIAostyNTUjCeSrUdKth9jcdlam9X2DziA/DHDFfS5eq4fEvABEBAAGJ ATwEGAEIACYCGwwWIQQt33LlpaVbqJ2qQuHCPZHzoSX+qAUCXZw1rgUJCWpOfwAKCRDCPZHz oSX+qFcEB/95cs8cM1OQdE/GgOfCGxwgckMeWyzOR7bkAWW0lDVp2hpgJuxBW/gyfmtBnUai fnggx3EE3ev8HTysZU9q0h+TJwwJKGv6sUc8qcTGFDtavnnl+r6xDUY7A6GvXEsSoCEEynby 72byGeSovfq/4AWGNPBG1L61Exl+gbqfvbECP3ziXnob009+z9I4qXodHSYINfAkZkA523JG ap12LndJeLk3gfWNZfXEWyGnuciRGbqESkhIRav8ootsCIops/SqXm0/k+Kcl4gGUO/iD/T5 oagaDh0QtOd8RWSMwLxwn8uIhpH84Q4X1LadJ5NCgGa6xPP5qqRuiC+9gZqbq4Nj Message-ID: <6db35b15-1f16-dfd8-368c-b03e428eba08@gmx.com> Date: Tue, 22 Sep 2020 18:34:18 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <4591966.Q0mfgpEauH@merkaba> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="ANoT8dRVQgFZZJmFGN0e6ZjwKdDCk0Z2C" X-Provags-ID: V03:K1:MfIBEOTNXxzC4UIEGZRtm/2nNsDAPLAwwuVlHJ3kP8Kbdsw/sx3 o5qOmFGG4sG90BOagbDvUof/2pg0VvX8tmHDddQk9Hlq3Mgu26kVsts2Tp+4d9ZOnrXU65v h9+q5yfIqpk46AFJjlBsarbN1rrrqV3cBOeKXtXEaeDJ+3nbBbI8IKHc7o0Jd3ZjzDRD8vH +fKK1OXti+JCzRx9nTK/Q== X-UI-Out-Filterresults: notjunk:1;V03:K0:6MrNvjgCYK4=:Vnd8yRwvwf13N0JX5U/AV+ Lj19KBF6TucEHRy9uV4IPine/ReuSho8EqoiBQRWFsR0x0Pwl3S5ARHmhmL0TjPW3euMWXg7n 1wAWPweWpj7W4iE1pGnZbPYkK722+vQXShHNVpT4pOEU/OhnZSVRwB+c+XO7c1c8OAabGIWmX 8NulSDgW6VI+Ok545tAKR9mqq6J633KEiT3rwdlI6wo1yt06D7xrOsG1zXGnz0BB6+m2SAvuO hGIsVNbQ/D8rO+5E3/dhIxMO0ZAbFa6ce8er8t2/yq2r1aK00xDDwW6lt+d33DbgaX4yiNpTz +OLayLosOwPT//FQLqQ8bRfOqi85AfZwGNQPlcaXOlzH7GEnktsjadSxT2wJ50y9ONC4Db+O6 oIDacvLsR5B6wcaZdbGOlMSZR4v4RBrH6jGHpYFzLRJQn8Yc1Q2xv3AuYlDNtBbv2Joz2UZeZ m1R3HMS1HiVj05wYaadiaKM0X7I4r9owUmVWsHufPAm3xX85r4zYJSgGeOb+6x8X51XBNZVjZ QxygX4fOImgPL22ChpmM5OXbFqUFz9ebPnDYW6+6Aw7GZMAjV1luZmi2La4CrTQZCyTZyYaSC 5vqoTIZS5pkZ0pNptPakenJgT3xIJb4pVQbgTNZFATSIeNbyhjAFsC8xcmznL8jPI6HhQvvrF mceAlBoWp8+qI5mr+WY+48lYo83C4lHi2g3fXp15Pwq2hkdJfuzzSevCaRiGKKpHNXNtU4mjJ D0us1QTgjv87CxkHjvVMyxX5fpOQJog3Nwo5/pQb8QF7vEjgXENiofM/KX8BVqydYrm9ByiOc wGgKA4X1W6rFqgrOnlj/zJTN7lBHjuVu5dH+MwYEcf0QBhQoqGi0++e1FM3aEaobWMjBBm3o1 AP1jSb6crRrcnoJI+oVqdioh93U39iMnditnB64YwKjt8/9jVt4JmWfJ8cPdmLPwrKiApqkJv bsK252BVkMknGm7ZYAbOnQZVk+BobRVtPLsB26M1m3N4hh9cWm7V0uEXzTsBTV4Jamg+jqnLA uGeFvhb4ws4kI/jfFJJ0Zi9nKBTg2M6T+NOIADQJxjMfrNpYxQIhWWC9u7oveQQbWFoYBKBUC rrmv6Ek0sKxRP/OWeaiLeHVAdC2pNP2bXFOrM2gGQBug+Dj9R6w0CZpUptbygxss3tZ+WTmGC fo9qUpBe35rBPAy8lMbtYokIa31ZjJo95pyL39rhbKNHmRrl7NaMXBXLiKb7K33aVgKJqvm8q QvkE9ppacByvBJWT2xXIjD4Xp7SR2yO5nFbBAPw== Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --ANoT8dRVQgFZZJmFGN0e6ZjwKdDCk0Z2C Content-Type: multipart/mixed; boundary="odu05pg9Dx9R1O28jXPjCJIhrTQAXnJs4" --odu05pg9Dx9R1O28jXPjCJIhrTQAXnJs4 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: quoted-printable On 2020/9/22 =E4=B8=8B=E5=8D=886:20, Martin Steigerwald wrote: > Hi Qu. >=20 > Instead of the tool, can I also patch my kernel with the patch below to= =20 > have it automatically fix it? Sure, this one is a little safer than the tool. >=20 > If so, which approach would you prefer for testing? >=20 > I can apply the patch as I compile kernels myself. That's great. That should solve the problem. And if you don't like the legacy root item, just do a balance (no matter data or metadata), and that legacy root item will be converted to current one, and even affected kernel won't report any error any more. Thanks, Qu >=20 > Thanks, > Martin >=20 > Qu Wenruo - 22.09.20, 04:37:01 CEST: >> Commit 259ee7754b67 ("btrfs: tree-checker: Add ROOT_ITEM check") >> introduced btrfs root item size check, however btrfs root item has two= >> format, the legacy one which just ends before generation_v2 member, >> is smaller than current btrfs root item size. >> >> This caused btrfs kernel to reject valid but old tree root leaves. >> >> Fix this problem by also allowing legacy root item, since kernel can >> already handle them pretty well and upgrade to newer root item format >> when needed. >> >> Reported-by: Martin Steigerwald >> Fixes: 259ee7754b67 ("btrfs: tree-checker: Add ROOT_ITEM check") >> Signed-off-by: Qu Wenruo >> --- >> fs/btrfs/tree-checker.c | 17 ++++++++++++----- >> include/uapi/linux/btrfs_tree.h | 9 +++++++++ >> 2 files changed, 21 insertions(+), 5 deletions(-) >> >> diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c >> index 7b1fee630f97..6f794aca48d3 100644 >> --- a/fs/btrfs/tree-checker.c >> +++ b/fs/btrfs/tree-checker.c >> @@ -1035,7 +1035,7 @@ static int check_root_item(struct extent_buffer >> *leaf, struct btrfs_key *key, int slot) >> { >> struct btrfs_fs_info *fs_info =3D leaf->fs_info; >> - struct btrfs_root_item ri; >> + struct btrfs_root_item ri =3D { 0 }; >> const u64 valid_root_flags =3D BTRFS_ROOT_SUBVOL_RDONLY | >> BTRFS_ROOT_SUBVOL_DEAD; >> int ret; >> @@ -1044,14 +1044,21 @@ static int check_root_item(struct >> extent_buffer *leaf, struct btrfs_key *key, if (ret < 0) >> return ret; >> >> - if (btrfs_item_size_nr(leaf, slot) !=3D sizeof(ri)) { >> + if (btrfs_item_size_nr(leaf, slot) !=3D sizeof(ri) && >> + btrfs_item_size_nr(leaf, slot) !=3D=20 > btrfs_legacy_root_item_size()) >> { generic_err(leaf, slot, >> - "invalid root item size, have %u expect %zu", >> - btrfs_item_size_nr(leaf, slot), sizeof(ri)); >> + "invalid root item size, have %u expect %zu or=20 > %zu", >> + btrfs_item_size_nr(leaf, slot), sizeof(ri), >> + btrfs_legacy_root_item_size()); >> } >> >> + /* >> + * For legacy root item, the members starting at generation_v2=20 > will >> be + * all filled with 0. >> + * And since we allow geneartion_v2 as 0, it will still pass the >> check. + */ >> read_extent_buffer(leaf, &ri, btrfs_item_ptr_offset(leaf, slot), >> - sizeof(ri)); >> + btrfs_item_size_nr(leaf, slot)); >> >> /* Generation related */ >> if (btrfs_root_generation(&ri) > >> diff --git a/include/uapi/linux/btrfs_tree.h >> b/include/uapi/linux/btrfs_tree.h index 9ba64ca6b4ac..464095a28b18 >> 100644 >> --- a/include/uapi/linux/btrfs_tree.h >> +++ b/include/uapi/linux/btrfs_tree.h >> @@ -644,6 +644,15 @@ struct btrfs_root_item { >> __le64 reserved[8]; /* for future */ >> } __attribute__ ((__packed__)); >> >> +/* >> + * Btrfs root item used to be smaller than current size. >> + * The old format ends at where member generation_v2 is. >> + */ >> +static inline size_t btrfs_legacy_root_item_size(void) >> +{ >> + return offsetof(struct btrfs_root_item, generation_v2); >> +} >> + >> /* >> * this is used for both forward and backward root refs >> */ >=20 >=20 --odu05pg9Dx9R1O28jXPjCJIhrTQAXnJs4-- --ANoT8dRVQgFZZJmFGN0e6ZjwKdDCk0Z2C Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAEBCAAdFiEELd9y5aWlW6idqkLhwj2R86El/qgFAl9p0yoACgkQwj2R86El /qg+iQf/bHCJa+Ipv4YCunv5wDvzRQEMMQP19Wt2GLyEYi/t9mdhSiwkhlskubHQ W+s1IghwAsYTfM5MU9w4Cq4b93DGh8zjOlPsVp5lK5PU3RvduB1zq/pNX1Jddxw9 dGhqdRYZPw6M7XvvsJSNad8K2X67bBhNuAnr15Vx6kO5UXPrtBf6LdKorX98yBeP ZtDRQk8Jr7QhJTI5bMWCcK0qU7z9r5fuZpVOZTgAzEgSE5l0BhvihKfNlUBEE9+x zEA7QBVlYV9fjpXAwBqRxVfGw26c3C1kgt0+kp9VadxsFH1r7NEoq825t++TqmlG k/Qt4/wrqUWEQJMeMD06WzqgDY2hmw== =kAQ7 -----END PGP SIGNATURE----- --ANoT8dRVQgFZZJmFGN0e6ZjwKdDCk0Z2C--