From patchwork Tue Apr 11 17:23:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13207960 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 A5891C77B73 for ; Tue, 11 Apr 2023 17:22:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229980AbjDKRW4 (ORCPT ); Tue, 11 Apr 2023 13:22:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49280 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229499AbjDKRWz (ORCPT ); Tue, 11 Apr 2023 13:22:55 -0400 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9B8C7122; Tue, 11 Apr 2023 10:22:53 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.227]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4Pwsqt00lBz9v7Hv; Wed, 12 Apr 2023 01:13:29 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwAHukBMlzVkOgEUAg--.766S2; Tue, 11 Apr 2023 18:22:29 +0100 (CET) From: Roberto Sassu To: zohar@linux.ibm.com, dmitry.kasatkin@gmail.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, stephen.smalley.work@gmail.com, eparis@parisplace.org, casey@schaufler-ca.com Cc: reiserfs-devel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, bpf@vger.kernel.org, kpsingh@kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH] Smack modifications for: security: Allow all LSMs to provide xattrs for inode_init_security hook Date: Tue, 11 Apr 2023 19:23:37 +0200 Message-Id: <20230411172337.340518-1-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-CM-TRANSID: GxC2BwAHukBMlzVkOgEUAg--.766S2 X-Coremail-Antispam: 1UD129KBjvJXoWxJF1fXF4DZrWxWFy5Ary3twb_yoW5KryDpF W7K3ZxKF4rtF1DWryFyF4UW3yakan5WrWUWwnxXws3ZFnFqw1xKF95Xr1YkF1xXrykZr9Y gF4qqr13WFn0y37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUv2b4IE77IF4wAFF20E14v26ryj6rWUM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4 vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7Cj xVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40E x7xfMcIj6xIIjxv20xvE14v26r106r15McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x 0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1lc7CjxVAa w2AFwI0_GFv_Wryl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxV Aqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a 6rW5MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6x kF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVW3JVWrJr1lIxAIcVC2z280aVAF wI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa 7IU0bAw3UUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgAEBF1jj4fclgACs8 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Roberto Sassu Very very quick modification. Not tested. Signed-off-by: Roberto Sassu --- security/smack/smack.h | 2 +- security/smack/smack_lsm.c | 42 ++++++++++++++++++++------------------ 2 files changed, 23 insertions(+), 21 deletions(-) diff --git a/security/smack/smack.h b/security/smack/smack.h index e2239be7bd6..f00c8498c60 100644 --- a/security/smack/smack.h +++ b/security/smack/smack.h @@ -127,7 +127,7 @@ struct task_smack { #define SMK_INODE_INSTANT 0x01 /* inode is instantiated */ #define SMK_INODE_TRANSMUTE 0x02 /* directory is transmuting */ -#define SMK_INODE_CHANGED 0x04 /* smack was transmuted */ +#define SMK_INODE_CHANGED 0x04 /* smack was transmuted (unused) */ #define SMK_INODE_IMPURE 0x08 /* involved in an impure transaction */ /* diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 8392983334b..b43820bdbd0 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -54,12 +54,12 @@ /* * Smack uses multiple xattrs. - * SMACK64 - for access control, SMACK64EXEC - label for the program, - * SMACK64MMAP - controls library loading, + * SMACK64 - for access control, * SMACK64TRANSMUTE - label initialization, - * Not saved on files - SMACK64IPIN and SMACK64IPOUT + * Not saved on files - SMACK64IPIN and SMACK64IPOUT, + * Must be set explicitly - SMACK64EXEC and SMACK64MMAP */ -#define SMACK_INODE_INIT_XATTRS 4 +#define SMACK_INODE_INIT_XATTRS 2 #ifdef SMACK_IPV6_PORT_LABELING static DEFINE_MUTEX(smack_ipv6_lock); @@ -957,11 +957,11 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, struct xattr *xattrs, int *xattr_count) { - struct inode_smack *issp = smack_inode(inode); struct smack_known *skp = smk_of_current(); struct smack_known *isp = smk_of_inode(inode); struct smack_known *dsp = smk_of_inode(dir); struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count); + struct xattr *xattr2; int may; if (xattr) { @@ -979,7 +979,17 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && smk_inode_transmutable(dir)) { isp = dsp; - issp->smk_flags |= SMK_INODE_CHANGED; + xattr2 = lsm_get_xattr_slot(xattrs, xattr_count); + if (xattr2) { + xattr2->value = kmemdup(TRANS_TRUE, + TRANS_TRUE_SIZE, + GFP_NOFS); + if (xattr2->value == NULL) + return -ENOMEM; + + xattr2->value_len = TRANS_TRUE_SIZE; + xattr2->name = XATTR_NAME_SMACKTRANSMUTE; + } } xattr->value = kstrdup(isp->smk_known, GFP_NOFS); @@ -3512,20 +3522,12 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) * If there is a transmute attribute on the * directory mark the inode. */ - if (isp->smk_flags & SMK_INODE_CHANGED) { - isp->smk_flags &= ~SMK_INODE_CHANGED; - rc = __vfs_setxattr(&nop_mnt_idmap, dp, inode, - XATTR_NAME_SMACKTRANSMUTE, - TRANS_TRUE, TRANS_TRUE_SIZE, - 0); - } else { - rc = __vfs_getxattr(dp, inode, - XATTR_NAME_SMACKTRANSMUTE, trattr, - TRANS_TRUE_SIZE); - if (rc >= 0 && strncmp(trattr, TRANS_TRUE, - TRANS_TRUE_SIZE) != 0) - rc = -EINVAL; - } + rc = __vfs_getxattr(dp, inode, + XATTR_NAME_SMACKTRANSMUTE, trattr, + TRANS_TRUE_SIZE); + if (rc >= 0 && strncmp(trattr, TRANS_TRUE, + TRANS_TRUE_SIZE) != 0) + rc = -EINVAL; if (rc >= 0) transflag = SMK_INODE_TRANSMUTE; }