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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 5FC60C07E99 for ; Mon, 5 Jul 2021 10:14:07 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C6ABC61416 for ; Mon, 5 Jul 2021 10:14:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C6ABC61416 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:34728 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1m0Lc5-0005Hx-TR for qemu-devel@archiver.kernel.org; Mon, 05 Jul 2021 06:14:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:38964) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m0LSm-0002zj-2m for qemu-devel@nongnu.org; Mon, 05 Jul 2021 06:04:28 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:38142) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1m0LSj-0001dS-V9 for qemu-devel@nongnu.org; Mon, 05 Jul 2021 06:04:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1625479465; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wEs+EGaCVwVgsdq9B8HBs51p7HnNdyJCliUHEwdX5Gg=; b=CD3QNgDwMBDGl327+jlNq/3cqjqJS/Tz77Wjb0qk9c1ovbcdtI8FtqTIfGQPPtZ6dNiYUQ aZVm2q2ZHWzQnjTRw7ZUd95YHG/5WfKGOOIs6mWKTGMNvHyDkksI9T1F2RvqhpDvB6yKD6 6K0sRnmvY9nFUKG6r6shho7tNrAsoNk= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-331-71IyafdhM_2MWg8WX-VmeA-1; Mon, 05 Jul 2021 06:04:23 -0400 X-MC-Unique: 71IyafdhM_2MWg8WX-VmeA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 90D488015F5; Mon, 5 Jul 2021 10:04:22 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-114-11.ams2.redhat.com [10.36.114.11]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0EB5C60C0F; Mon, 5 Jul 2021 10:04:19 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, berrange@redhat.com, linfeng23@huawei.com, groug@kaod.org, huangy81@chinatelecom.cn, lvivier@redhat.com, lizhijian@cn.fujitsu.com, peterx@redhat.com, vgoyal@redhat.com Subject: [PULL 14/19] virtiofsd: Add capability to change/restore umask Date: Mon, 5 Jul 2021 11:02:30 +0100 Message-Id: <20210705100235.157093-15-dgilbert@redhat.com> In-Reply-To: <20210705100235.157093-1-dgilbert@redhat.com> References: <20210705100235.157093-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="US-ASCII" Received-SPF: pass client-ip=216.205.24.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -42 X-Spam_score: -4.3 X-Spam_bar: ---- X-Spam_report: (-4.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.441, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: leobras@redhat.com, stefanha@redhat.com, quintela@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Vivek Goyal When parent directory has default acl and a file is created in that directory, then umask is ignored and final file permissions are determined using default acl instead. (man 2 umask). Currently, fuse applies the umask and sends modified mode in create request accordingly. fuse server can set FUSE_DONT_MASK and tell fuse client to not apply umask and fuse server will take care of it as needed. With posix acls enabled, requirement will be that we want umask to determine final file mode if parent directory does not have default acl. So if posix acls are enabled, opt in for FUSE_DONT_MASK. virtiofsd will set umask of the thread doing file creation. And host kernel should use that umask if parent directory does not have default acls, otherwise umask does not take affect. Miklos mentioned that we already call unshare(CLONE_FS) for every thread. That means umask has now become property of per thread and it should be ok to manipulate it in file creation path. This patch only adds capability to change umask and restore it. It does not enable it yet. Next few patches will add capability to enable it based on if user enabled posix_acl or not. This should fix fstest generic/099. Reported-by: Luis Henriques Signed-off-by: Vivek Goyal Reviewed-by: Stefan Hajnoczi Reviewed-by: Dr. David Alan Gilbert Message-Id: <20210622150852.1507204-6-vgoyal@redhat.com> Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 4dec087bd4..65b2c6fd74 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -122,6 +122,7 @@ struct lo_inode { struct lo_cred { uid_t euid; gid_t egid; + mode_t umask; }; enum { @@ -172,6 +173,8 @@ struct lo_data { /* An O_PATH file descriptor to /proc/self/fd/ */ int proc_self_fd; int user_killpriv_v2, killpriv_v2; + /* If set, virtiofsd is responsible for setting umask during creation */ + bool change_umask; }; static const struct fuse_opt lo_opts[] = { @@ -1134,7 +1137,8 @@ static void lo_lookup(fuse_req_t req, fuse_ino_t parent, const char *name) * ownership of caller. * TODO: What about selinux context? */ -static int lo_change_cred(fuse_req_t req, struct lo_cred *old) +static int lo_change_cred(fuse_req_t req, struct lo_cred *old, + bool change_umask) { int res; @@ -1154,11 +1158,14 @@ static int lo_change_cred(fuse_req_t req, struct lo_cred *old) return errno_save; } + if (change_umask) { + old->umask = umask(req->ctx.umask); + } return 0; } /* Regain Privileges */ -static void lo_restore_cred(struct lo_cred *old) +static void lo_restore_cred(struct lo_cred *old, bool restore_umask) { int res; @@ -1173,6 +1180,9 @@ static void lo_restore_cred(struct lo_cred *old) fuse_log(FUSE_LOG_ERR, "setegid(%u): %m\n", old->egid); exit(1); } + + if (restore_umask) + umask(old->umask); } static void lo_mknod_symlink(fuse_req_t req, fuse_ino_t parent, @@ -1202,7 +1212,7 @@ static void lo_mknod_symlink(fuse_req_t req, fuse_ino_t parent, return; } - saverr = lo_change_cred(req, &old); + saverr = lo_change_cred(req, &old, lo->change_umask && !S_ISLNK(mode)); if (saverr) { goto out; } @@ -1211,7 +1221,7 @@ static void lo_mknod_symlink(fuse_req_t req, fuse_ino_t parent, saverr = errno; - lo_restore_cred(&old); + lo_restore_cred(&old, lo->change_umask && !S_ISLNK(mode)); if (res == -1) { goto out; @@ -1917,7 +1927,7 @@ static void lo_create(fuse_req_t req, fuse_ino_t parent, const char *name, return; } - err = lo_change_cred(req, &old); + err = lo_change_cred(req, &old, lo->change_umask); if (err) { goto out; } @@ -1928,7 +1938,7 @@ static void lo_create(fuse_req_t req, fuse_ino_t parent, const char *name, fd = openat(parent_inode->fd, name, fi->flags | O_CREAT | O_EXCL, mode); err = fd == -1 ? errno : 0; - lo_restore_cred(&old); + lo_restore_cred(&old, lo->change_umask); /* Ignore the error if file exists and O_EXCL was not given */ if (err && (err != EEXIST || (fi->flags & O_EXCL))) { -- 2.31.1