From patchwork Wed Jun 7 12:36:10 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13270644 X-Patchwork-Delegate: paul@paul-moore.com 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 DEC00C87FDE for ; Wed, 7 Jun 2023 12:37:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240011AbjFGMhX (ORCPT ); Wed, 7 Jun 2023 08:37:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46546 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239605AbjFGMhD (ORCPT ); Wed, 7 Jun 2023 08:37:03 -0400 Received: from frasgout12.his.huawei.com (unknown [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2549173A; Wed, 7 Jun 2023 05:37:01 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4Qbmkp2Yghz9xFb8; Wed, 7 Jun 2023 20:25:06 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCnJgLMeYBkSckaAw--.4176S5; Wed, 07 Jun 2023 13:36:47 +0100 (CET) From: Roberto Sassu To: casey@schaufler-ca.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com Cc: linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, Roberto Sassu Subject: [RFC][PATCH 3/5] smack: Always determine inode labels in smack_inode_init_security() Date: Wed, 7 Jun 2023 14:36:10 +0200 Message-Id: <20230607123612.2791303-4-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230607123612.2791303-1-roberto.sassu@huaweicloud.com> References: <20230607123612.2791303-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCnJgLMeYBkSckaAw--.4176S5 X-Coremail-Antispam: 1UD129KBjvJXoWxJFWkWr1rKry7tr1xGF1rJFb_yoWrGr4fpa yUWa9xCF1ktFnxu3y0yF47Ww4YkFyrCr4UWr9Fqr9avFsrtryIqrW0qryYgFyxXr97Zrn0 qr4avryrZ3WY9wUanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBFb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUWw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2 WlYx0E2Ix0cI8IcVAFwI0_JrI_JrylYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkE bVWUJVW8JwACjcxG0xvY0x0EwIxGrwCY1x0262kKe7AKxVW8ZVWrXwCF04k20xvY0x0EwI xGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI42IY6xAI w20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z280aVCY1x 0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07jzE__UUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgABBF1jj4pZywABsv X-CFilter-Loop: Reflected Precedence: bulk List-ID: From: Roberto Sassu The inode_init_security hook is already a good place to initialize the in-memory inode. And that is also what SELinux does. In preparation for this, move the existing smack_inode_init_security() code outside the 'if (xattr)' condition, and set the xattr, if provided. This change does not have any impact on the current code, since every time security_inode_init_security() is called, the initxattr() callback is passed and, thus, xattr is non-NULL. Signed-off-by: Roberto Sassu --- security/smack/smack_lsm.c | 78 +++++++++++++++++++------------------- 1 file changed, 40 insertions(+), 38 deletions(-) diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 162ca400f07..f7382448e12 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -948,49 +948,51 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); int may; - if (xattr) { - /* - * If equal, transmuting already occurred in - * smack_dentry_create_files_as(). No need to check again. - */ - if (tsp->smk_task != tsp->smk_transmuted) { - rcu_read_lock(); - may = smk_access_entry(skp->smk_known, dsp->smk_known, - &skp->smk_rules); - rcu_read_unlock(); - } + /* + * If equal, transmuting already occurred in + * smack_dentry_create_files_as(). No need to check again. + */ + if (tsp->smk_task != tsp->smk_transmuted) { + rcu_read_lock(); + may = smk_access_entry(skp->smk_known, dsp->smk_known, + &skp->smk_rules); + rcu_read_unlock(); + } + + /* + * In addition to having smk_task equal to smk_transmuted, + * if the access rule allows transmutation and the directory + * requests transmutation then by all means transmute. + * Mark the inode as changed. + */ + if ((tsp->smk_task == tsp->smk_transmuted) || + (may > 0 && ((may & MAY_TRANSMUTE) != 0) && + smk_inode_transmutable(dir))) { + struct xattr *xattr_transmute; /* - * In addition to having smk_task equal to smk_transmuted, - * if the access rule allows transmutation and the directory - * requests transmutation then by all means transmute. - * Mark the inode as changed. + * The caller of smack_dentry_create_files_as() + * should have overridden the current cred, so the + * inode label was already set correctly in + * smack_inode_alloc_security(). */ - if ((tsp->smk_task == tsp->smk_transmuted) || - (may > 0 && ((may & MAY_TRANSMUTE) != 0) && - smk_inode_transmutable(dir))) { - struct xattr *xattr_transmute; - - /* - * The caller of smack_dentry_create_files_as() - * should have overridden the current cred, so the - * inode label was already set correctly in - * smack_inode_alloc_security(). - */ - if (tsp->smk_task != tsp->smk_transmuted) - isp = dsp; - xattr_transmute = lsm_get_xattr_slot(xattrs, xattr_count); - if (xattr_transmute) { - xattr_transmute->value = kmemdup(TRANS_TRUE, - TRANS_TRUE_SIZE, GFP_NOFS); - if (xattr_transmute->value == NULL) - return -ENOMEM; - - xattr_transmute->value_len = TRANS_TRUE_SIZE; - xattr_transmute->name = XATTR_SMACK_TRANSMUTE; - } + if (tsp->smk_task != tsp->smk_transmuted) + isp = dsp; + + xattr_transmute = lsm_get_xattr_slot(xattrs, xattr_count); + if (xattr_transmute) { + xattr_transmute->value = kmemdup(TRANS_TRUE, + TRANS_TRUE_SIZE, + GFP_NOFS); + if (xattr_transmute->value == NULL) + return -ENOMEM; + + xattr_transmute->value_len = TRANS_TRUE_SIZE; + xattr_transmute->name = XATTR_SMACK_TRANSMUTE; } + } + if (xattr) { xattr->value = kstrdup(isp->smk_known, GFP_NOFS); if (xattr->value == NULL) return -ENOMEM;