From patchwork Mon Jul 24 12:13:05 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 13324548 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 409BEC0015E for ; Mon, 24 Jul 2023 12:13:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230141AbjGXMNR (ORCPT ); Mon, 24 Jul 2023 08:13:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229477AbjGXMNQ (ORCPT ); Mon, 24 Jul 2023 08:13:16 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57F791BF; Mon, 24 Jul 2023 05:13:15 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CF7266111F; Mon, 24 Jul 2023 12:13:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 391B9C433C8; Mon, 24 Jul 2023 12:13:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690200794; bh=5lARTRlkcLkwGHmez9f9aPfhEdGhUKlUDQvXf3fnxUs=; h=From:Date:Subject:To:Cc:From; b=SgkOYSbsypxENA7qLIE42GPi9QQvDn8kOXcpBs79FktLXUKABXbRW5Rp0VaUuWdpr G+VwtwKT/iDQ0hWPf2bNTb/xYVk07Ch+4ssYK44I7Xul9htnH76ar4YvwczNlZMa0d binvBO7joXNFSYEWB4+AQAHyf+I6XNerocP/F7xczKsZQA9HA1554fSP2JnVolErqG FtPjo7eD7zAPUuapTl0wsfyEaxUwPXAZhGlzRWyq4mWo7TSLzt5Acg5f5qFvAX8x10 ZrXj+LWb0/bepQMTJXeoxtsbRrM3TyaaSmVlFPZR/9Nr8c8+oVk2TkBHldqptLDw+A 3ejBpJ3E34LKQ== From: Jeff Layton Date: Mon, 24 Jul 2023 08:13:05 -0400 Subject: [PATCH v2] nfsd: inherit required unset default acls from effective set MIME-Version: 1.0 Message-Id: <20230724-nfsd-acl-v2-1-1cfaac973498@kernel.org> X-B4-Tracking: v=1; b=H4sIANBqvmQC/23Myw6CMBCF4Vchs3ZML0KDK9/DsCh0ChNJMa1pN KTvbmXt8j85+XZIFJkSXJsdImVOvIUa6tTAtNgwE7KrDUooLYzsMfjk0E4rtnbsZKsNXaiDen9 G8vw+qPtQe+H02uLnkLP8rX+QLFEijcJbr53qpbk9KAZaz1ucYSilfAEAo/veoQAAAA== To: Chuck Lever , Neil Brown , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: Andreas Gruenbacher , linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Ondrej Valousek , Jeff Layton X-Mailer: b4 0.12.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=5550; i=jlayton@kernel.org; h=from:subject:message-id; bh=5lARTRlkcLkwGHmez9f9aPfhEdGhUKlUDQvXf3fnxUs=; b=owEBbQKS/ZANAwAIAQAOaEEZVoIVAcsmYgBkvmrY2NPF3xcpJD5VmN8da0rZmazOFfAGJk/vF 3yCe0PvzwGJAjMEAAEIAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCZL5q2AAKCRAADmhBGVaC FYz2D/9avmrWR7g+tY4C0l/iG/c6BSsASRhbPCfBfaCtCFD0HI54YZPjqG7rxh5sE75gOd4l8ht sdzNc2qew/AleCsn4e8lIN1+hFvGRh2VTSuiE36GdudaU5qrW9J/9jm3F/Af7vT3PDtes5RxQBZ 1sNYi++smIz+NS/h+TWZndRTH/Psgm0M7X7yeH5n1yELqmkAC1z5uRJUPdsDifNY4gyUq1f72QZ IKeeWuUlB1ppts9Gl76SGKoZqLOs7hvr4jrSC/98eAEvJ23DVYvEwwFC7wWRGfbP5r0urBF/CD0 2NdG6AHIGfeBuCHhJc6bswZEEX+9FiEMrrMgCpcAFfKcgjbNzd9FkHPE7IcQJFNUfBXbIu5vnM0 NIWm3Ht95ciJtsxsdf8ajF9r+vW5lW+KI3jlNXbqDBibyFgKacg0NLQhaeBAkJsqko4vnDo/Vug sc7IA1sv576yblWC8YkYB1snbg1cedQ/RiYnh5AEllHmJyK0vchlqxYu/DlH+rTKZRVD4mEqocO 5jG58cJ1LCVBvLDpZvVsZcYrQQz0Q6DU/qiD4nAl+mse223g2p1FNgvLwamAL5AO6hYOrZdsE9Z sPeRRAEnxz+9OsYuLdgovKQv8iWUSjGy2CXwgfVZazrvX/mN+hdw8PAASaAdlXYdV3sNbMwSkZG iZNZKz0dPL7Lqsw== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org A well-formed NFSv4 ACL will always contain OWNER@/GROUP@/EVERYONE@ ACEs, but there is no requirement for inheritable entries for those entities. POSIX ACLs must always have owner/group/other entries, even for a default ACL. nfsd builds the default ACL from inheritable ACEs, but the current code just leaves any unspecified ACEs zeroed out. The result is that adding a default user or group ACE to an inode can leave it with unwanted deny entries. For instance, a newly created directory with no acl will look something like this: # NFSv4 translation by server A::OWNER@:rwaDxtTcCy A::GROUP@:rxtcy A::EVERYONE@:rxtcy # POSIX ACL of underlying file user::rwx group::r-x other::r-x ...if I then add new v4 ACE: nfs4_setfacl -a A:fd:1000:rwx /mnt/local/test ...I end up with a result like this today: user::rwx user:1000:rwx group::r-x mask::rwx other::r-x default:user::--- default:user:1000:rwx default:group::--- default:mask::rwx default:other::--- A::OWNER@:rwaDxtTcCy A::1000:rwaDxtcy A::GROUP@:rxtcy A::EVERYONE@:rxtcy D:fdi:OWNER@:rwaDx A:fdi:OWNER@:tTcCy A:fdi:1000:rwaDxtcy A:fdi:GROUP@:tcy A:fdi:EVERYONE@:tcy ...which is not at all expected. Adding a single inheritable allow ACE should not result in everyone else losing access. The setfacl command solves a silimar issue by copying owner/group/other entries from the effective ACL when none of them are set: "If a Default ACL entry is created, and the Default ACL contains no owner, owning group, or others entry, a copy of the ACL owner, owning group, or others entry is added to the Default ACL. Having nfsd do the same provides a more sane result (with no deny ACEs in the resulting set): user::rwx user:1000:rwx group::r-x mask::rwx other::r-x default:user::rwx default:user:1000:rwx default:group::r-x default:mask::rwx default:other::r-x A::OWNER@:rwaDxtTcCy A::1000:rwaDxtcy A::GROUP@:rxtcy A::EVERYONE@:rxtcy A:fdi:OWNER@:rwaDxtTcCy A:fdi:1000:rwaDxtcy A:fdi:GROUP@:rxtcy A:fdi:EVERYONE@:rxtcy Reported-by: Ondrej Valousek Closes: https://bugzilla.redhat.com/show_bug.cgi?id=2136452 Suggested-by: Andreas Gruenbacher Signed-off-by: Jeff Layton --- Changes in v2: - always set missing ACEs whenever default ACL has any ACEs that are explicitly set. This better conforms to how setfacl works. - drop now-unneeded "empty" boolean - Link to v1: https://lore.kernel.org/r/20230719-nfsd-acl-v1-1-eb0faf3d2917@kernel.org --- fs/nfsd/nfs4acl.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-) --- base-commit: 7bfb36a2ee1d329a501ba4781db4145dc951c798 change-id: 20230719-nfsd-acl-5ab61537e4e6 Best regards, diff --git a/fs/nfsd/nfs4acl.c b/fs/nfsd/nfs4acl.c index 518203821790..b931d4383517 100644 --- a/fs/nfsd/nfs4acl.c +++ b/fs/nfsd/nfs4acl.c @@ -441,7 +441,7 @@ struct posix_ace_state_array { * calculated so far: */ struct posix_acl_state { - int empty; + unsigned char valid; struct posix_ace_state owner; struct posix_ace_state group; struct posix_ace_state other; @@ -457,7 +457,6 @@ init_state(struct posix_acl_state *state, int cnt) int alloc; memset(state, 0, sizeof(struct posix_acl_state)); - state->empty = 1; /* * In the worst case, each individual acl could be for a distinct * named user or group, but we don't know which, so we allocate @@ -500,7 +499,7 @@ posix_state_to_acl(struct posix_acl_state *state, unsigned int flags) * and effective cases: when there are no inheritable ACEs, * calls ->set_acl with a NULL ACL structure. */ - if (state->empty && (flags & NFS4_ACL_TYPE_DEFAULT)) + if (!state->valid && (flags & NFS4_ACL_TYPE_DEFAULT)) return NULL; /* @@ -622,9 +621,10 @@ static void process_one_v4_ace(struct posix_acl_state *state, struct nfs4_ace *ace) { u32 mask = ace->access_mask; + short type = ace2type(ace); int i; - state->empty = 0; + state->valid |= type; switch (ace2type(ace)) { case ACL_USER_OBJ: @@ -726,6 +726,30 @@ static int nfs4_acl_nfsv4_to_posix(struct nfs4_acl *acl, if (!(ace->flag & NFS4_ACE_INHERIT_ONLY_ACE)) process_one_v4_ace(&effective_acl_state, ace); } + + /* + * At this point, the default ACL may have zeroed-out entries for owner, + * group and other. That usually results in a non-sensical resulting ACL + * that denies all access except to any ACE that was explicitly added. + * + * The setfacl command solves a similar problem with this logic: + * + * "If a Default ACL entry is created, and the Default ACL contains + * no owner, owning group, or others entry, a copy of the ACL + * owner, owning group, or others entry is added to the Default ACL." + * + * Copy any missing ACEs from the effective set, if any ACEs were + * explicitly set. + */ + if (default_acl_state.valid) { + if (!(default_acl_state.valid & ACL_USER_OBJ)) + default_acl_state.owner = effective_acl_state.owner; + if (!(default_acl_state.valid & ACL_GROUP_OBJ)) + default_acl_state.group = effective_acl_state.group; + if (!(default_acl_state.valid & ACL_OTHER)) + default_acl_state.other = effective_acl_state.other; + } + *pacl = posix_state_to_acl(&effective_acl_state, flags); if (IS_ERR(*pacl)) { ret = PTR_ERR(*pacl);