From patchwork Tue Mar 14 08:17:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13173882 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 D34F1C6FD1F for ; Tue, 14 Mar 2023 08:20:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229946AbjCNIUM (ORCPT ); Tue, 14 Mar 2023 04:20:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230063AbjCNIT0 (ORCPT ); Tue, 14 Mar 2023 04:19:26 -0400 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 72CCF1A643; Tue, 14 Mar 2023 01:18:46 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4PbR5Y4Ghfz9xFfL; Tue, 14 Mar 2023 16:09:53 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwBnNl2zLRBkenSXAQ--.34127S3; Tue, 14 Mar 2023 09:18:17 +0100 (CET) From: Roberto Sassu To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, 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: ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v8 1/6] reiserfs: Switch to security_inode_init_security() Date: Tue, 14 Mar 2023 09:17:15 +0100 Message-Id: <20230314081720.4158676-2-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> References: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwBnNl2zLRBkenSXAQ--.34127S3 X-Coremail-Antispam: 1UD129KBjvJXoWxur45GF1DJry5Wr15JFW7twb_yoW5Xw13pF 47K3WUKr4kJF1Igr1Fya13W3WSgrWfGw47JrsxKrWDAanrJw18trW0yw13u34rGrZ7Jr1I qw409wsxCws8JwUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBjb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGw A2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8JVWxJwA2z4x0Y4vEx4A2jsIE14v26r4j6F4UM28EF7xvwVC2z280aVCY1x0267AKxVW8 JVW8Jr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx 0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWU JVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20xvY0x0EwI xGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k2 6cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07jn9N3UUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAQAQBF1jj4qHYQAAsI X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu In preparation for removing security_old_inode_init_security(), switch to security_inode_init_security(). Commit 572302af1258 ("reiserfs: Add missing calls to reiserfs_security_free()") fixed possible memory leaks and another issue related to adding an xattr at inode creation time. Define the initxattrs callback reiserfs_initxattrs(), to populate the name/value/len triple in the reiserfs_security_handle() with the first xattr provided by LSMs. Make a copy of the xattr value, as security_inode_init_security() frees it. After the call to security_inode_init_security(), remove the check for returning -EOPNOTSUPP, as security_inode_init_security() changes it to zero. Multiple xattrs are currently not supported, as the reiserfs_security_handle structure is exported to user space. As a consequence, even if EVM is invoked, it will not provide an xattr (if it is not the first to set it, its xattr will be discarded; if it is the first, it does not have xattrs to calculate the HMAC on). Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar --- fs/reiserfs/xattr_security.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/fs/reiserfs/xattr_security.c b/fs/reiserfs/xattr_security.c index 41c0ea84fbf..6bffdf9a4fd 100644 --- a/fs/reiserfs/xattr_security.c +++ b/fs/reiserfs/xattr_security.c @@ -39,6 +39,22 @@ static bool security_list(struct dentry *dentry) return !IS_PRIVATE(d_inode(dentry)); } +static int +reiserfs_initxattrs(struct inode *inode, const struct xattr *xattr_array, + void *fs_info) +{ + struct reiserfs_security_handle *sec = fs_info; + + sec->value = kmemdup(xattr_array->value, xattr_array->value_len, + GFP_KERNEL); + if (!sec->value) + return -ENOMEM; + + sec->name = xattr_array->name; + sec->length = xattr_array->value_len; + return 0; +} + /* Initializes the security context for a new inode and returns the number * of blocks needed for the transaction. If successful, reiserfs_security * must be released using reiserfs_security_free when the caller is done. */ @@ -56,12 +72,9 @@ int reiserfs_security_init(struct inode *dir, struct inode *inode, if (IS_PRIVATE(dir)) return 0; - error = security_old_inode_init_security(inode, dir, qstr, &sec->name, - &sec->value, &sec->length); + error = security_inode_init_security(inode, dir, qstr, + &reiserfs_initxattrs, sec); if (error) { - if (error == -EOPNOTSUPP) - error = 0; - sec->name = NULL; sec->value = NULL; sec->length = 0; From patchwork Tue Mar 14 08:17:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13173883 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 25CFAC74A44 for ; Tue, 14 Mar 2023 08:20:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229472AbjCNIUN (ORCPT ); Tue, 14 Mar 2023 04:20:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60190 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230175AbjCNITc (ORCPT ); Tue, 14 Mar 2023 04:19:32 -0400 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9195798E92; Tue, 14 Mar 2023 01:18:54 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4PbR5k5nxmz9v7H0; Tue, 14 Mar 2023 16:10:02 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwBnNl2zLRBkenSXAQ--.34127S4; Tue, 14 Mar 2023 09:18:26 +0100 (CET) From: Roberto Sassu To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, 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: ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v8 2/6] ocfs2: Switch to security_inode_init_security() Date: Tue, 14 Mar 2023 09:17:16 +0100 Message-Id: <20230314081720.4158676-3-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> References: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwBnNl2zLRBkenSXAQ--.34127S4 X-Coremail-Antispam: 1UD129KBjvJXoWxCw4rKFyxJrWkZFy8Gr17ZFb_yoWrWr15pa n8K3W5tr1fJFy8WrWrJr4rua1SgrWfGrsrJr93GryDZFs8Cr1ftryFyr1UCas8XrZ8JFyk tF4Ykrn3Cwn8Ja7anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBYb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV WxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ Gr0_Gr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_ Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64 vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8G jcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MIIYrxkI7VAKI48JMIIF0xvE2I x0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26F4j6r4UJwCI42IY6xAI w20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x 0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU1sa9DUUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgAQBF1jj4aJfgAAsW X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu In preparation for removing security_old_inode_init_security(), switch to security_inode_init_security(). Extend the existing ocfs2_initxattrs() to take the ocfs2_security_xattr_info structure from fs_info, and populate the name/value/len triple with the first xattr provided by LSMs. As fs_info was not used before, ocfs2_initxattrs() can now handle the case of replicating the behavior of security_old_inode_init_security(), i.e. just obtaining the xattr, in addition to setting all xattrs provided by LSMs. Supporting multiple xattrs is not currently supported where security_old_inode_init_security() was called (mknod, symlink), as it requires non-trivial changes that can be done at a later time. Like for reiserfs, even if EVM is invoked, it will not provide an xattr (if it is not the first to set it, its xattr will be discarded; if it is the first, it does not have xattrs to calculate the HMAC on). Finally, since security_inode_init_security(), unlike security_old_inode_init_security(), returns zero instead of -EOPNOTSUPP if no xattrs were provided by LSMs or if inodes are private, additionally check in ocfs2_init_security_get() if the xattr name is set. If not, act as if security_old_inode_init_security() returned -EOPNOTSUPP, and set si->enable to zero to notify to the functions following ocfs2_init_security_get() that no xattrs are available. Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Acked-by: Joseph Qi Reviewed-by: Mimi Zohar --- fs/ocfs2/namei.c | 2 ++ fs/ocfs2/xattr.c | 30 ++++++++++++++++++++++++++---- 2 files changed, 28 insertions(+), 4 deletions(-) diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c index 9175dbc4720..17c52225b87 100644 --- a/fs/ocfs2/namei.c +++ b/fs/ocfs2/namei.c @@ -242,6 +242,7 @@ static int ocfs2_mknod(struct mnt_idmap *idmap, int want_meta = 0; int xattr_credits = 0; struct ocfs2_security_xattr_info si = { + .name = NULL, .enable = 1, }; int did_quota_inode = 0; @@ -1805,6 +1806,7 @@ static int ocfs2_symlink(struct mnt_idmap *idmap, int want_clusters = 0; int xattr_credits = 0; struct ocfs2_security_xattr_info si = { + .name = NULL, .enable = 1, }; int did_quota = 0, did_quota_inode = 0; diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 389308efe85..469ec45baee 100644 --- a/fs/ocfs2/xattr.c +++ b/fs/ocfs2/xattr.c @@ -7259,9 +7259,21 @@ static int ocfs2_xattr_security_set(const struct xattr_handler *handler, static int ocfs2_initxattrs(struct inode *inode, const struct xattr *xattr_array, void *fs_info) { + struct ocfs2_security_xattr_info *si = fs_info; const struct xattr *xattr; int err = 0; + if (si) { + si->value = kmemdup(xattr_array->value, xattr_array->value_len, + GFP_KERNEL); + if (!si->value) + return -ENOMEM; + + si->name = xattr_array->name; + si->value_len = xattr_array->value_len; + return 0; + } + for (xattr = xattr_array; xattr->name != NULL; xattr++) { err = ocfs2_xattr_set(inode, OCFS2_XATTR_INDEX_SECURITY, xattr->name, xattr->value, @@ -7277,13 +7289,23 @@ int ocfs2_init_security_get(struct inode *inode, const struct qstr *qstr, struct ocfs2_security_xattr_info *si) { + int ret; + /* check whether ocfs2 support feature xattr */ if (!ocfs2_supports_xattr(OCFS2_SB(dir->i_sb))) return -EOPNOTSUPP; - if (si) - return security_old_inode_init_security(inode, dir, qstr, - &si->name, &si->value, - &si->value_len); + if (si) { + ret = security_inode_init_security(inode, dir, qstr, + &ocfs2_initxattrs, si); + /* + * security_inode_init_security() does not return -EOPNOTSUPP, + * we have to check the xattr ourselves. + */ + if (!ret && !si->name) + si->enable = 0; + + return ret; + } return security_inode_init_security(inode, dir, qstr, &ocfs2_initxattrs, NULL); From patchwork Tue Mar 14 08:17:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13173884 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 F1D29C6FD1C for ; Tue, 14 Mar 2023 08:20:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229684AbjCNIUO (ORCPT ); Tue, 14 Mar 2023 04:20:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230242AbjCNITv (ORCPT ); Tue, 14 Mar 2023 04:19:51 -0400 Received: from frasgout12.his.huawei.com (frasgout12.his.huawei.com [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA13B74A6E; Tue, 14 Mar 2023 01:19:04 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.227]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4PbR5C4qlkz9xHN2; Tue, 14 Mar 2023 16:09:35 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwBnNl2zLRBkenSXAQ--.34127S5; Tue, 14 Mar 2023 09:18:35 +0100 (CET) From: Roberto Sassu To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, 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: ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v8 3/6] security: Remove security_old_inode_init_security() Date: Tue, 14 Mar 2023 09:17:17 +0100 Message-Id: <20230314081720.4158676-4-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> References: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwBnNl2zLRBkenSXAQ--.34127S5 X-Coremail-Antispam: 1UD129KBjvJXoWxGryDZrW7Xw18WryDZry7ZFb_yoW5GryrpF 43t3WUGr1rJFyUWr1vyF17uF1SgFWrKrsrJrsakwnrJFnxZr1rtF1Fyr17CFyrJrW8Ww1I qw4a9r43Gr4DJrDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBYb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUWw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV WxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ Gr0_Gr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_ Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64 vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8G jcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MIIYrxkI7VAKI48JMIIF0xvE2I x0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26F4j6r4UJwCI42IY6xAI w20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x 0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU1c4S7UUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgAQBF1jj4aJfgABsX X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu As the remaining two users reiserfs and ocfs2 switched to security_inode_init_security(), security_old_inode_init_security() can be now removed. Out-of-tree kernel modules should switch to security_inode_init_security() too. Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar --- include/linux/security.h | 12 ------------ security/security.c | 11 ----------- 2 files changed, 23 deletions(-) diff --git a/include/linux/security.h b/include/linux/security.h index 5984d0d550b..cd23221ce9e 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -336,9 +336,6 @@ int security_inode_init_security(struct inode *inode, struct inode *dir, int security_inode_init_security_anon(struct inode *inode, const struct qstr *name, const struct inode *context_inode); -int security_old_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, const char **name, - void **value, size_t *len); int security_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode); int security_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry); @@ -778,15 +775,6 @@ static inline int security_inode_init_security_anon(struct inode *inode, return 0; } -static inline int security_old_inode_init_security(struct inode *inode, - struct inode *dir, - const struct qstr *qstr, - const char **name, - void **value, size_t *len) -{ - return -EOPNOTSUPP; -} - static inline int security_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode) diff --git a/security/security.c b/security/security.c index b808e1b8655..f4170efcddd 100644 --- a/security/security.c +++ b/security/security.c @@ -1655,17 +1655,6 @@ int security_inode_init_security_anon(struct inode *inode, context_inode); } -int security_old_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, const char **name, - void **value, size_t *len) -{ - if (unlikely(IS_PRIVATE(inode))) - return -EOPNOTSUPP; - return call_int_hook(inode_init_security, -EOPNOTSUPP, inode, dir, - qstr, name, value, len); -} -EXPORT_SYMBOL(security_old_inode_init_security); - #ifdef CONFIG_SECURITY_PATH /** * security_path_mknod() - Check if creating a special file is allowed From patchwork Tue Mar 14 08:17:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13173885 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 5A50AC6FD1F for ; Tue, 14 Mar 2023 08:20:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230137AbjCNIUi (ORCPT ); Tue, 14 Mar 2023 04:20:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59314 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231148AbjCNIT6 (ORCPT ); Tue, 14 Mar 2023 04:19:58 -0400 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1013610267; Tue, 14 Mar 2023 01:19:17 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.229]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4PbR691kwYz9xHdb; Tue, 14 Mar 2023 16:10:25 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwBnNl2zLRBkenSXAQ--.34127S6; Tue, 14 Mar 2023 09:18:47 +0100 (CET) From: Roberto Sassu To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, 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: ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v8 4/6] security: Allow all LSMs to provide xattrs for inode_init_security hook Date: Tue, 14 Mar 2023 09:17:18 +0100 Message-Id: <20230314081720.4158676-5-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> References: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwBnNl2zLRBkenSXAQ--.34127S6 X-Coremail-Antispam: 1UD129KBjvAXoW3Kr1DWw4kCrykJw4fJw1xAFb_yoW8XFy8Zo WxJwsrZrW0gr17KrW5u3Z7JFWDuayrWr4fAr1Fvr45A3Zxtw1UCw13Xa18XFW3WryrKr48 t34Iya40qrWqqrn5n29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7v73VFW2AGmfu7bjvjm3 AaLaJ3UjIYCTnIWjp_UUUYu7kC6x804xWl14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK 8VAvwI8IcIk0rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF 0E3s1l82xGYIkIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vE j48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xIIjxv20xvEc7CjxV AFwI0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26r4j6F4UM28EF7xvwVC2z280aVCY1x02 67AKxVW8Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F4 0Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC 6x0Yz7v_Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82 IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC2 0s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MIIYrxkI7VAKI48JMI IF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26F4j6r4UJwCI 42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z2 80aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU13l1DUUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAQAQBF1jj4qHYwAAsK X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu Currently, security_inode_init_security() supports only one LSM providing an xattr and EVM calculating the HMAC on that xattr, plus other inode metadata. Allow all LSMs to provide one or multiple xattrs, by extending the security blob reservation mechanism. Introduce the new lbs_xattr field of the lsm_blob_sizes structure, so that each LSM can specify how many xattrs it needs, and the LSM infrastructure knows how many xattr slots it should allocate. Dynamically allocate the xattrs array to be populated by LSMs with the inode_init_security hook, and pass it to the latter instead of the name/value/len triple. Update the documentation accordingly, and fix the description of the xattr name, as it is not allocated anymore. Since the LSM infrastructure, at initialization time, updates the number of the requested xattrs provided by each LSM with a corresponding offset in the security blob (in this case the xattr array), it makes straightforward for an LSM to access the right position in the xattr array. There is still the issue that an LSM might not fill the xattr, even if it requests it (legitimate case, for example it might have been loaded but not initialized with a policy). Since users of the xattr array (e.g. the initxattrs() callbacks) detect the end of the xattr array by checking if the xattr name is NULL, not filling an xattr would cause those users to stop scanning xattrs prematurely. Solve that issue by introducing security_check_compact_filled_xattrs(), which does a basic check of the xattr array (if the xattr name is filled, the xattr value should be too, and viceversa), and compacts the xattr array by removing the holes. An alternative solution would be to let users of the xattr array know the number of elements of that array, so that they don't have to check the termination. However, this seems more invasive, compared to a simple move of few array elements. security_check_compact_filled_xattrs() also determines how many xattrs in the xattr array have been filled. If there is none, skip evm_inode_init_security() and initxattrs(). Skipping the former also avoids EVM to crash the kernel, as it is expecting a filled xattr. Finally, adapt both SELinux and Smack to use the new definition of the inode_init_security hook, and to correctly fill the designated slots in the xattr array. For Smack, reserve space for the other defined xattrs although they are not set yet in smack_inode_init_security(). Reported-by: Nicolas Bouchinet (EVM crash) Link: https://lore.kernel.org/linux-integrity/Y1FTSIo+1x+4X0LS@archlinux/ Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar --- include/linux/lsm_hook_defs.h | 3 +- include/linux/lsm_hooks.h | 1 + security/security.c | 119 +++++++++++++++++++++++++++++----- security/selinux/hooks.c | 19 ++++-- security/smack/smack_lsm.c | 33 ++++++---- 5 files changed, 137 insertions(+), 38 deletions(-) diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 6bb55e61e8e..b814955ae70 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -112,8 +112,7 @@ LSM_HOOK(int, 0, path_notify, const struct path *path, u64 mask, LSM_HOOK(int, 0, inode_alloc_security, struct inode *inode) LSM_HOOK(void, LSM_RET_VOID, inode_free_security, struct inode *inode) LSM_HOOK(int, 0, inode_init_security, struct inode *inode, - struct inode *dir, const struct qstr *qstr, const char **name, - void **value, size_t *len) + struct inode *dir, const struct qstr *qstr, struct xattr *xattrs) LSM_HOOK(int, 0, inode_init_security_anon, struct inode *inode, const struct qstr *name, const struct inode *context_inode) LSM_HOOK(int, 0, inode_create, struct inode *dir, struct dentry *dentry, diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h index c2be66c669a..75a2f85b49d 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -63,6 +63,7 @@ struct lsm_blob_sizes { int lbs_ipc; int lbs_msg_msg; int lbs_task; + int lbs_xattr; /* number of xattr slots in new_xattrs array */ }; /* diff --git a/security/security.c b/security/security.c index f4170efcddd..f1f5f62f7fa 100644 --- a/security/security.c +++ b/security/security.c @@ -31,8 +31,6 @@ #include #include -#define MAX_LSM_EVM_XATTR 2 - /* How many LSMs were built into the kernel? */ #define LSM_COUNT (__end_lsm_info - __start_lsm_info) @@ -212,6 +210,7 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed) lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg); lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock); lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task); + lsm_set_blob_size(&needed->lbs_xattr, &blob_sizes.lbs_xattr); } /* Prepare LSM for initialization. */ @@ -378,6 +377,7 @@ static void __init ordered_lsm_init(void) init_debug("msg_msg blob size = %d\n", blob_sizes.lbs_msg_msg); init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock); init_debug("task blob size = %d\n", blob_sizes.lbs_task); + init_debug("xattr slots = %d\n", blob_sizes.lbs_xattr); /* * Create any kmem_caches needed for blobs @@ -1579,6 +1579,52 @@ int security_dentry_create_files_as(struct dentry *dentry, int mode, } EXPORT_SYMBOL(security_dentry_create_files_as); +/** + * security_check_compact_filled_xattrs - check xattrs and make array contiguous + * @xattrs: xattr array filled by LSMs + * @num_xattrs: length of xattr array + * @num_filled_xattrs: number of already processed xattrs + * + * Ensure that each xattr slot is correctly filled and close the gaps in the + * xattr array if an LSM didn't provide an xattr for which it asked space + * (legitimate case, it might have been loaded but not initialized). An LSM + * might request space in the xattr array for one or multiple xattrs. The LSM + * infrastructure ensures that all requests by LSMs are satisfied. + * + * Track the number of filled xattrs in @num_filled_xattrs, so that it is easy + * to determine whether the currently processed xattr is fine in its position + * (if all previous xattrs were filled) or it should be moved after the last + * filled xattr. + * + * Return: zero if all xattrs are valid, -EINVAL otherwise. + */ +static int security_check_compact_filled_xattrs(struct xattr *xattrs, + int num_xattrs, + int *num_filled_xattrs) +{ + int i; + + for (i = *num_filled_xattrs; i < num_xattrs; i++) { + if ((!xattrs[i].name && xattrs[i].value) || + (xattrs[i].name && !xattrs[i].value)) + return -EINVAL; + + if (!xattrs[i].name) + continue; + + if (i == *num_filled_xattrs) { + (*num_filled_xattrs)++; + continue; + } + + memcpy(xattrs + (*num_filled_xattrs)++, xattrs + i, + sizeof(*xattrs)); + memset(xattrs + i, 0, sizeof(*xattrs)); + } + + return 0; +} + /** * security_inode_init_security() - Initialize an inode's LSM context * @inode: the inode @@ -1591,9 +1637,13 @@ EXPORT_SYMBOL(security_dentry_create_files_as); * created inode and set up the incore security field for the new inode. This * hook is called by the fs code as part of the inode creation transaction and * provides for atomic labeling of the inode, unlike the post_create/mkdir/... - * hooks called by the VFS. The hook function is expected to allocate the name - * and value via kmalloc, with the caller being responsible for calling kfree - * after using them. If the security module does not use security attributes + * hooks called by the VFS. The hook function is expected to populate the + * @xattrs array, depending on how many xattrs have been specified by the + * security module in the lbs_xattr field of the lsm_blob_sizes structure. For + * each array element, the hook function is expected to set ->name to the + * attribute name suffix (e.g. selinux), to allocate ->value (will be freed by + * the caller) and set it to the attribute value, to set ->value_len to the + * length of the value. If the security module does not use security attributes * or does not wish to put a security attribute on this particular inode, then * it should return -EOPNOTSUPP to skip this processing. * @@ -1604,33 +1654,66 @@ int security_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, const initxattrs initxattrs, void *fs_data) { - struct xattr new_xattrs[MAX_LSM_EVM_XATTR + 1]; - struct xattr *lsm_xattr, *evm_xattr, *xattr; - int ret; + struct security_hook_list *P; + struct xattr *new_xattrs; + struct xattr *xattr; + int ret = -EOPNOTSUPP, num_filled_xattrs = 0; if (unlikely(IS_PRIVATE(inode))) return 0; + if (!blob_sizes.lbs_xattr) + return 0; + if (!initxattrs) return call_int_hook(inode_init_security, -EOPNOTSUPP, inode, - dir, qstr, NULL, NULL, NULL); - memset(new_xattrs, 0, sizeof(new_xattrs)); - lsm_xattr = new_xattrs; - ret = call_int_hook(inode_init_security, -EOPNOTSUPP, inode, dir, qstr, - &lsm_xattr->name, - &lsm_xattr->value, - &lsm_xattr->value_len); - if (ret) + dir, qstr, NULL); + /* Allocate +1 for EVM and +1 as terminator. */ + new_xattrs = kcalloc(blob_sizes.lbs_xattr + 2, sizeof(*new_xattrs), + GFP_NOFS); + if (!new_xattrs) + return -ENOMEM; + + hlist_for_each_entry(P, &security_hook_heads.inode_init_security, + list) { + ret = P->hook.inode_init_security(inode, dir, qstr, new_xattrs); + if (ret && ret != -EOPNOTSUPP) + goto out; + /* + * As documented in lsm_hooks.h, -EOPNOTSUPP in this context + * means that the LSM is not willing to provide an xattr, not + * that it wants to signal an error. Thus, continue to invoke + * the remaining LSMs. + */ + if (ret == -EOPNOTSUPP) + continue; + /* + * As the number of xattrs reserved by LSMs is not directly + * available, directly use the total number blob_sizes.lbs_xattr + * to keep the code simple, while being not the most efficient + * way. + */ + ret = security_check_compact_filled_xattrs(new_xattrs, + blob_sizes.lbs_xattr, + &num_filled_xattrs); + if (ret < 0) { + ret = -ENOMEM; + goto out; + } + } + + if (!num_filled_xattrs) goto out; - evm_xattr = lsm_xattr + 1; - ret = evm_inode_init_security(inode, lsm_xattr, evm_xattr); + ret = evm_inode_init_security(inode, new_xattrs, + new_xattrs + num_filled_xattrs); if (ret) goto out; ret = initxattrs(inode, new_xattrs, fs_data); out: for (xattr = new_xattrs; xattr->value != NULL; xattr++) kfree(xattr->value); + kfree(new_xattrs); return (ret == -EOPNOTSUPP) ? 0 : ret; } EXPORT_SYMBOL(security_inode_init_security); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 9a5bdfc2131..3e4308dd336 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -104,6 +104,8 @@ #include "audit.h" #include "avc_ss.h" +#define SELINUX_INODE_INIT_XATTRS 1 + struct selinux_state selinux_state; /* SECMARK reference count */ @@ -2868,11 +2870,11 @@ static int selinux_dentry_create_files_as(struct dentry *dentry, int mode, static int selinux_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, - const char **name, - void **value, size_t *len) + struct xattr *xattrs) { const struct task_security_struct *tsec = selinux_cred(current_cred()); struct superblock_security_struct *sbsec; + struct xattr *xattr = NULL; u32 newsid, clen; int rc; char *context; @@ -2899,16 +2901,18 @@ static int selinux_inode_init_security(struct inode *inode, struct inode *dir, !(sbsec->flags & SBLABEL_MNT)) return -EOPNOTSUPP; - if (name) - *name = XATTR_SELINUX_SUFFIX; + if (xattrs) + xattr = xattrs + selinux_blob_sizes.lbs_xattr; + + if (xattr) { + xattr->name = XATTR_SELINUX_SUFFIX; - if (value && len) { rc = security_sid_to_context_force(&selinux_state, newsid, &context, &clen); if (rc) return rc; - *value = context; - *len = clen; + xattr->value = context; + xattr->value_len = clen; } return 0; @@ -6918,6 +6922,7 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = { .lbs_ipc = sizeof(struct ipc_security_struct), .lbs_msg_msg = sizeof(struct msg_security_struct), .lbs_superblock = sizeof(struct superblock_security_struct), + .lbs_xattr = SELINUX_INODE_INIT_XATTRS, }; #ifdef CONFIG_PERF_EVENTS diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index cfcbb748da2..c8cf8df268b 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -52,6 +52,15 @@ #define SMK_RECEIVING 1 #define SMK_SENDING 2 +/* + * Smack uses multiple xattrs. + * SMACK64 - for access control, SMACK64EXEC - label for the program, + * SMACK64MMAP - controls library loading, + * SMACK64TRANSMUTE - label initialization, + * Not saved on files - SMACK64IPIN and SMACK64IPOUT + */ +#define SMACK_INODE_INIT_XATTRS 4 + #ifdef SMACK_IPV6_PORT_LABELING static DEFINE_MUTEX(smack_ipv6_lock); static LIST_HEAD(smk_ipv6_port_list); @@ -939,26 +948,27 @@ static int smack_inode_alloc_security(struct inode *inode) * @inode: the newly created inode * @dir: containing directory object * @qstr: unused - * @name: where to put the attribute name - * @value: where to put the attribute value - * @len: where to put the length of the attribute + * @xattrs: where to put the attributes * * Returns 0 if it all works out, -ENOMEM if there's no memory */ static int smack_inode_init_security(struct inode *inode, struct inode *dir, - const struct qstr *qstr, const char **name, - void **value, size_t *len) + const struct qstr *qstr, + struct xattr *xattrs) { 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 = NULL; int may; - if (name) - *name = XATTR_SMACK_SUFFIX; + if (xattrs) + xattr = xattrs + smack_blob_sizes.lbs_xattr; + + if (xattr) { + xattr->name = XATTR_SMACK_SUFFIX; - if (value && len) { rcu_read_lock(); may = smk_access_entry(skp->smk_known, dsp->smk_known, &skp->smk_rules); @@ -976,11 +986,11 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, issp->smk_flags |= SMK_INODE_CHANGED; } - *value = kstrdup(isp->smk_known, GFP_NOFS); - if (*value == NULL) + xattr->value = kstrdup(isp->smk_known, GFP_NOFS); + if (xattr->value == NULL) return -ENOMEM; - *len = strlen(isp->smk_known); + xattr->value_len = strlen(isp->smk_known); } return 0; @@ -4854,6 +4864,7 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = { .lbs_ipc = sizeof(struct smack_known *), .lbs_msg_msg = sizeof(struct smack_known *), .lbs_superblock = sizeof(struct superblock_smack), + .lbs_xattr = SMACK_INODE_INIT_XATTRS, }; static struct security_hook_list smack_hooks[] __lsm_ro_after_init = { From patchwork Tue Mar 14 08:17:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13173886 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 D8676C6FD1C for ; Tue, 14 Mar 2023 08:20:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230205AbjCNIUw (ORCPT ); Tue, 14 Mar 2023 04:20:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59422 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231217AbjCNIUB (ORCPT ); Tue, 14 Mar 2023 04:20:01 -0400 Received: from frasgout11.his.huawei.com (frasgout11.his.huawei.com [14.137.139.23]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 635EFBDCF; Tue, 14 Mar 2023 01:19:27 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout11.his.huawei.com (SkyGuard) with ESMTP id 4PbR6J2K6Cz9xqnn; Tue, 14 Mar 2023 16:10:32 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwBnNl2zLRBkenSXAQ--.34127S7; Tue, 14 Mar 2023 09:18:58 +0100 (CET) From: Roberto Sassu To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, 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: ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v8 5/6] evm: Align evm_inode_init_security() definition with LSM infrastructure Date: Tue, 14 Mar 2023 09:17:19 +0100 Message-Id: <20230314081720.4158676-6-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> References: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwBnNl2zLRBkenSXAQ--.34127S7 X-Coremail-Antispam: 1UD129KBjvJXoWxXF43tw1DXry7Kry5AF45Awb_yoWrKryUpa y3ta4UCr1rJFyUWryFyF4xu3WSgFWrGr4Ut393GryjyF1Dtr1xtrySyr15Cry5X3y8GFnY qw42vr1rWwn8t3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI 42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z2 80aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07UZo7tUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAQAQBF1jj4qHYwABsL X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu Change the evm_inode_init_security() definition to align with the LSM infrastructure. Keep the existing behavior of including in the HMAC calculation only the first xattr provided by LSMs. Changing the evm_inode_init_security() definition requires passing only the xattr array allocated by security_inode_init_security(), instead of the first LSM xattr and the place where the EVM xattr should be filled. In lieu of passing the EVM xattr, EVM must position itself after the last filled xattr (by checking the xattr name), since only the beginning of the xattr array is given. Finally, make evm_inode_init_security() return value compatible with the inode_init_security hook conventions, i.e. return -EOPNOTSUPP if it is not setting an xattr. EVM is a bit tricky, because xattrs is both an input and an output. If it was just output, EVM should have returned zero if xattrs is NULL. But, since xattrs is also input, EVM is unable to do its calculations, so return -EOPNOTSUPP and handle this error in security_inode_init_security(). Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar --- include/linux/evm.h | 12 ++++++------ security/integrity/evm/evm_main.c | 25 ++++++++++++++++++------- security/security.c | 5 ++--- 3 files changed, 26 insertions(+), 16 deletions(-) diff --git a/include/linux/evm.h b/include/linux/evm.h index 7dc1ee74169..cc64cea354e 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -56,9 +56,9 @@ static inline void evm_inode_post_set_acl(struct dentry *dentry, { return evm_inode_post_setxattr(dentry, acl_name, NULL, 0); } -extern int evm_inode_init_security(struct inode *inode, - const struct xattr *xattr_array, - struct xattr *evm); +extern int evm_inode_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, + struct xattr *xattrs); extern bool evm_revalidate_status(const char *xattr_name); extern int evm_protected_xattr_if_enabled(const char *req_xattr_name); extern int evm_read_protected_xattrs(struct dentry *dentry, u8 *buffer, @@ -157,9 +157,9 @@ static inline void evm_inode_post_set_acl(struct dentry *dentry, return; } -static inline int evm_inode_init_security(struct inode *inode, - const struct xattr *xattr_array, - struct xattr *evm) +static inline int evm_inode_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, + struct xattr *xattrs) { return 0; } diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index cf24c525558..7d20ce83915 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -864,23 +864,34 @@ void evm_inode_post_setattr(struct dentry *dentry, int ia_valid) /* * evm_inode_init_security - initializes security.evm HMAC value */ -int evm_inode_init_security(struct inode *inode, - const struct xattr *lsm_xattr, - struct xattr *evm_xattr) +int evm_inode_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, + struct xattr *xattrs) { struct evm_xattr *xattr_data; + struct xattr *xattr, *evm_xattr; int rc; - if (!(evm_initialized & EVM_INIT_HMAC) || - !evm_protected_xattr(lsm_xattr->name)) - return 0; + if (!(evm_initialized & EVM_INIT_HMAC) || !xattrs || + !evm_protected_xattr(xattrs->name)) + return -EOPNOTSUPP; + + /* + * security_inode_init_security() makes sure that the xattrs array is + * contiguous, there is enough space for security.evm, and that there is + * a terminator at the end of the array. + */ + for (xattr = xattrs; xattr->name != NULL; xattr++) + ; + + evm_xattr = xattr; xattr_data = kzalloc(sizeof(*xattr_data), GFP_NOFS); if (!xattr_data) return -ENOMEM; xattr_data->data.type = EVM_XATTR_HMAC; - rc = evm_init_hmac(inode, lsm_xattr, xattr_data->digest); + rc = evm_init_hmac(inode, xattrs, xattr_data->digest); if (rc < 0) goto out; diff --git a/security/security.c b/security/security.c index f1f5f62f7fa..d0e20b26b6c 100644 --- a/security/security.c +++ b/security/security.c @@ -1705,9 +1705,8 @@ int security_inode_init_security(struct inode *inode, struct inode *dir, if (!num_filled_xattrs) goto out; - ret = evm_inode_init_security(inode, new_xattrs, - new_xattrs + num_filled_xattrs); - if (ret) + ret = evm_inode_init_security(inode, dir, qstr, new_xattrs); + if (ret && ret != -EOPNOTSUPP) goto out; ret = initxattrs(inode, new_xattrs, fs_data); out: From patchwork Tue Mar 14 08:17:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13173887 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 034F1C6FD1F for ; Tue, 14 Mar 2023 08:20:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230346AbjCNIU5 (ORCPT ); Tue, 14 Mar 2023 04:20:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59428 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231245AbjCNIUD (ORCPT ); Tue, 14 Mar 2023 04:20:03 -0400 Received: from frasgout12.his.huawei.com (frasgout12.his.huawei.com [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C30BE17CDB; Tue, 14 Mar 2023 01:19:36 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4PbR5q2phCz9xqtb; Tue, 14 Mar 2023 16:10:07 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP2 (Coremail) with SMTP id GxC2BwBnNl2zLRBkenSXAQ--.34127S8; Tue, 14 Mar 2023 09:19:07 +0100 (CET) From: Roberto Sassu To: mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com, 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: ocfs2-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, linux-kernel@vger.kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v8 6/6] evm: Support multiple LSMs providing an xattr Date: Tue, 14 Mar 2023 09:17:20 +0100 Message-Id: <20230314081720.4158676-7-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> References: <20230314081720.4158676-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: GxC2BwBnNl2zLRBkenSXAQ--.34127S8 X-Coremail-Antispam: 1UD129KBjvJXoWxGryktFy8Jr45JrWUJFWfAFb_yoWrJFWkpa 98ta9rCrn5GFyUur9ayF48ua4SgrWrKw4UKwsxCr1jyFnFqr1Iqryxtr1Uur98WryrJrna vw40vw15Cw15t3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI 42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z2 80aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07UZo7tUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgAQBF1jj4aJggAAsq X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Roberto Sassu Currently, evm_inode_init_security() processes a single LSM xattr from the array passed by security_inode_init_security(), and calculates the HMAC on it and other inode metadata. Given that initxattrs() callbacks, called by security_inode_init_security(), expect that this array is terminated when the xattr name is set to NULL, reuse the same assumption to scan all xattrs and to calculate the HMAC on all of them. Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Reviewed-by: Mimi Zohar --- security/integrity/evm/evm.h | 2 ++ security/integrity/evm/evm_crypto.c | 9 ++++++++- security/integrity/evm/evm_main.c | 16 +++++++++++----- 3 files changed, 21 insertions(+), 6 deletions(-) diff --git a/security/integrity/evm/evm.h b/security/integrity/evm/evm.h index f8b8c5004fc..f799d72a59f 100644 --- a/security/integrity/evm/evm.h +++ b/security/integrity/evm/evm.h @@ -46,6 +46,8 @@ struct evm_digest { char digest[IMA_MAX_DIGEST_SIZE]; } __packed; +int evm_protected_xattr(const char *req_xattr_name); + int evm_init_key(void); int evm_update_evmxattr(struct dentry *dentry, const char *req_xattr_name, diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c index 033804f5a5f..5d8b5ecf594 100644 --- a/security/integrity/evm/evm_crypto.c +++ b/security/integrity/evm/evm_crypto.c @@ -389,6 +389,7 @@ int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr, char *hmac_val) { struct shash_desc *desc; + const struct xattr *xattr; desc = init_desc(EVM_XATTR_HMAC, HASH_ALGO_SHA1); if (IS_ERR(desc)) { @@ -396,7 +397,13 @@ int evm_init_hmac(struct inode *inode, const struct xattr *lsm_xattr, return PTR_ERR(desc); } - crypto_shash_update(desc, lsm_xattr->value, lsm_xattr->value_len); + for (xattr = lsm_xattr; xattr->name != NULL; xattr++) { + if (!evm_protected_xattr(xattr->name)) + continue; + + crypto_shash_update(desc, xattr->value, xattr->value_len); + } + hmac_add_misc(desc, inode, EVM_XATTR_HMAC, hmac_val); kfree(desc); return 0; diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index 7d20ce83915..013eb220cc5 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -305,7 +305,7 @@ static int evm_protected_xattr_common(const char *req_xattr_name, return found; } -static int evm_protected_xattr(const char *req_xattr_name) +int evm_protected_xattr(const char *req_xattr_name) { return evm_protected_xattr_common(req_xattr_name, false); } @@ -870,10 +870,10 @@ int evm_inode_init_security(struct inode *inode, struct inode *dir, { struct evm_xattr *xattr_data; struct xattr *xattr, *evm_xattr; + bool evm_protected_xattrs = false; int rc; - if (!(evm_initialized & EVM_INIT_HMAC) || !xattrs || - !evm_protected_xattr(xattrs->name)) + if (!(evm_initialized & EVM_INIT_HMAC) || !xattrs) return -EOPNOTSUPP; /* @@ -881,8 +881,14 @@ int evm_inode_init_security(struct inode *inode, struct inode *dir, * contiguous, there is enough space for security.evm, and that there is * a terminator at the end of the array. */ - for (xattr = xattrs; xattr->name != NULL; xattr++) - ; + for (xattr = xattrs; xattr->name != NULL; xattr++) { + if (evm_protected_xattr(xattr->name)) + evm_protected_xattrs = true; + } + + /* EVM xattr not needed. */ + if (!evm_protected_xattrs) + return -EOPNOTSUPP; evm_xattr = xattr;