From patchwork Thu Dec 1 10:41:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13061194 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 4024EC43217 for ; Thu, 1 Dec 2022 10:43:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230514AbiLAKnM (ORCPT ); Thu, 1 Dec 2022 05:43:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51252 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230478AbiLAKmn (ORCPT ); Thu, 1 Dec 2022 05:42:43 -0500 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C5BF62ADC; Thu, 1 Dec 2022 02:42:34 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.229]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4NNCC93B8dz9v7Yy; Thu, 1 Dec 2022 18:35:33 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCHcm_phIhjrxuvAA--.49496S3; Thu, 01 Dec 2022 11:42:06 +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 v7 1/6] reiserfs: Switch to security_inode_init_security() Date: Thu, 1 Dec 2022 11:41:20 +0100 Message-Id: <20221201104125.919483-2-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> References: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCHcm_phIhjrxuvAA--.49496S3 X-Coremail-Antispam: 1UD129KBjvJXoWxZF13CFWkJw1ktF48uryfWFg_yoW5Jw4rpF 43K3W7Krs8JF1Igr1Sya13W3WfKrWfKw47JrsxKryDAanrJr1rtry0yw13u34rGrZ7Jr1I qw4Ivw43Cws8JwUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBYb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGw A2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8JVWxJwA2z4x0Y4vEx4A2jsIE14v26r4j6F4UM28EF7xvwVC2z280aVCY1x0267AKxVW8 Jr0_Cr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_ Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64 vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8G jcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r4a6rW5MIIYrxkI7VAKI48JMIIF0xvE2I x0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK 8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I 0E14v26r4UJVWxJrUvcSsGvfC2KfnxnUUI43ZEXa7IU8-TmDUUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAQANBF1jj4YhwwAAsd X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@vger.kernel.org From: Roberto Sassu In preparation for removing security_old_inode_init_security(), switch to security_inode_init_security(). 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 857a65b05726..0ba96757681d 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 Thu Dec 1 10:41:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13061195 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 DD9A0C4321E for ; Thu, 1 Dec 2022 10:43:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230463AbiLAKne (ORCPT ); Thu, 1 Dec 2022 05:43:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50522 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230146AbiLAKnD (ORCPT ); Thu, 1 Dec 2022 05:43:03 -0500 Received: from frasgout12.his.huawei.com (frasgout12.his.huawei.com [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 70DAB286D9; Thu, 1 Dec 2022 02:42:44 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.227]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4NNCCv1ZgLz9xFY9; Thu, 1 Dec 2022 18:36:11 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCHcm_phIhjrxuvAA--.49496S4; Thu, 01 Dec 2022 11:42:16 +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 v7 2/6] ocfs2: Switch to security_inode_init_security() Date: Thu, 1 Dec 2022 11:41:21 +0100 Message-Id: <20221201104125.919483-3-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> References: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCHcm_phIhjrxuvAA--.49496S4 X-Coremail-Antispam: 1UD129KBjvJXoWxtw4kKF1UJw1rCrW5Aw1fZwb_yoW7Xr1Upa 1ftFnxtr4rJFyUWryftr45ua1S9rWrGrZrGrs3G34DZFn8Cr1ftry0yr15ua45XrWDJFyk tr4Fkrsxuan8J37anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUB2b4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV WxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ Gr1j6F4UJwAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ew Av7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY 6r1j6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxAIw28IcxkI7V AKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCj r7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY6x IIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcVCF 04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7 CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuYvjxUFa9-UUUUU X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgANBF1jj4IjiwAAsQ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@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, modify the handling of the return value from ocfs2_init_security_get(). As security_inode_init_security() does not return -EOPNOTSUPP, remove this case and directly handle the error if the return value is not zero. However, the previous case of receiving -EOPNOTSUPP should be still taken into account, as security_inode_init_security() could return zero without setting xattrs and ocfs2 would consider it as if the xattr was set. Instead, if security_inode_init_security() returned zero, look at the xattr if it was set, and behave accordingly, i.e. set si->enable to zero to notify to the functions following ocfs2_init_security_get() that the xattr is not available (same as if security_old_inode_init_security() returned -EOPNOTSUPP). Signed-off-by: Roberto Sassu Reviewed-by: Casey Schaufler Acked-by: Joseph Qi --- fs/ocfs2/namei.c | 18 ++++++------------ fs/ocfs2/xattr.c | 30 ++++++++++++++++++++++++++---- 2 files changed, 32 insertions(+), 16 deletions(-) diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c index 05f32989bad6..55fba81cd2d1 100644 --- a/fs/ocfs2/namei.c +++ b/fs/ocfs2/namei.c @@ -242,6 +242,7 @@ static int ocfs2_mknod(struct user_namespace *mnt_userns, int want_meta = 0; int xattr_credits = 0; struct ocfs2_security_xattr_info si = { + .name = NULL, .enable = 1, }; int did_quota_inode = 0; @@ -315,12 +316,8 @@ static int ocfs2_mknod(struct user_namespace *mnt_userns, /* get security xattr */ status = ocfs2_init_security_get(inode, dir, &dentry->d_name, &si); if (status) { - if (status == -EOPNOTSUPP) - si.enable = 0; - else { - mlog_errno(status); - goto leave; - } + mlog_errno(status); + goto leave; } /* calculate meta data/clusters for setting security and acl xattr */ @@ -1805,6 +1802,7 @@ static int ocfs2_symlink(struct user_namespace *mnt_userns, 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; @@ -1875,12 +1873,8 @@ static int ocfs2_symlink(struct user_namespace *mnt_userns, /* get security xattr */ status = ocfs2_init_security_get(inode, dir, &dentry->d_name, &si); if (status) { - if (status == -EOPNOTSUPP) - si.enable = 0; - else { - mlog_errno(status); - goto bail; - } + mlog_errno(status); + goto bail; } /* calculate meta data/clusters for setting security xattr */ diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c index 95d0611c5fc7..55699c573541 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 Thu Dec 1 10:41:22 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13061196 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 0DF8AC43217 for ; Thu, 1 Dec 2022 10:43:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230501AbiLAKnh (ORCPT ); Thu, 1 Dec 2022 05:43:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51202 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230467AbiLAKnE (ORCPT ); Thu, 1 Dec 2022 05:43:04 -0500 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 833932CCB8; Thu, 1 Dec 2022 02:42:53 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4NNCCW6FwVz9v7Yy; Thu, 1 Dec 2022 18:35:51 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCHcm_phIhjrxuvAA--.49496S5; Thu, 01 Dec 2022 11:42:25 +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 v7 3/6] security: Remove security_old_inode_init_security() Date: Thu, 1 Dec 2022 11:41:22 +0100 Message-Id: <20221201104125.919483-4-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> References: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCHcm_phIhjrxuvAA--.49496S5 X-Coremail-Antispam: 1UD129KBjvJXoWxGrWUJw1UXryDJr1kuF48JFb_yoW5Gr4rpF 43t3WUGr1rJFyjgF10yF47u3WfKFWrKrZrJrZak3sxAFn3Zr1rtF1Fyr17CFyrJrW8Ww1I qw4a9r43Gr4DtrDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUB2b4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUWw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVWUJVWUCwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV WxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW8JVWxJwA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ Gr1j6F4UJwAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ew Av7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY 6r1j6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxAIw28IcxkI7V AKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCj r7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0EwIxGrwCI42IY6x IIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcVCF 04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7 CjxVAFwI0_Gr1j6F4UJbIYCTnIWIevJa73UjIFyTuYvjxUFYFCUUUUU X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgANBF1jj4IjiwABsR X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@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 ca1b7109c0db..c682fc96ed61 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); @@ -771,15 +768,6 @@ 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 79d82cb6e469..e2857446fd32 100644 --- a/security/security.c +++ b/security/security.c @@ -1132,17 +1132,6 @@ 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 int security_path_mknod(const struct path *dir, struct dentry *dentry, umode_t mode, unsigned int dev) From patchwork Thu Dec 1 10:41:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13061197 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 5D178C4708C for ; Thu, 1 Dec 2022 10:44:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230506AbiLAKoB (ORCPT ); Thu, 1 Dec 2022 05:44:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50564 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230481AbiLAKnN (ORCPT ); Thu, 1 Dec 2022 05:43:13 -0500 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 102CB32042; Thu, 1 Dec 2022 02:43:02 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.227]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4NNCCj0pFfz9xFfr; Thu, 1 Dec 2022 18:36:01 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCHcm_phIhjrxuvAA--.49496S6; Thu, 01 Dec 2022 11:42:34 +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 v7 4/6] security: Allow all LSMs to provide xattrs for inode_init_security hook Date: Thu, 1 Dec 2022 11:41:23 +0100 Message-Id: <20221201104125.919483-5-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> References: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCHcm_phIhjrxuvAA--.49496S6 X-Coremail-Antispam: 1UD129KBjvAXoW3Kr1DWw4kCrykJw4fJw1xAFb_yoW8XFW3Co WxJwsrZrW0gr17GrW5u3Z7JFZruayrWr4fAr1Fvr45A3ZIq34UCw1fXay8XF9xWryrKr48 t34Iya40qrWqqr95n29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7v73VFW2AGmfu7bjvjm3 AaLaJ3UjIYCTnIWjp_UUUYu7kC6x804xWl14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK 8VAvwI8IcIk0rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JF 0E3s1l82xGYIkIc2x26xkF7I0E14v26ryj6s0DM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vE j48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xIIjxv20xvEc7CjxV AFwI0_Cr0_Gr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF 0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVW8JVWxJwCI42IY6I8E87 Iv6xkF7I0E14v26r4UJVWxJrUvcSsGvfC2KfnxnUUI43ZEXa7IU13l1DUUUUU== X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgANBF1jj4IjiwACsS X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@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) 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 | 17 ++++-- security/security.c | 109 +++++++++++++++++++++++++++++----- security/selinux/hooks.c | 19 +++--- security/smack/smack_lsm.c | 33 ++++++---- 5 files changed, 140 insertions(+), 41 deletions(-) diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index ec119da1d89b..be344d0211f8 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 4ec80b96c22e..ba1655370643 100644 --- a/include/linux/lsm_hooks.h +++ b/include/linux/lsm_hooks.h @@ -229,18 +229,22 @@ * 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. + * is expected to allocate the value via kmalloc, with the caller + * being responsible for calling kfree after using it. * 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. * @inode contains the inode structure of the newly created inode. * @dir contains the inode structure of the parent directory. * @qstr contains the last path component of the new object - * @name will be set to the allocated name suffix (e.g. selinux). - * @value will be set to the allocated attribute value. - * @len will be set to the length of the value. - * Returns 0 if @name and @value have been successfully set, + * @xattrs contains the full array of xattrs provided by LSMs where + * ->name will be set to the name suffix (e.g. selinux). + * ->value will be set to the allocated attribute value. + * ->value_len will be set to the length of the value. + * Slots in @xattrs need to be reserved by LSMs by providing the number of + * the desired xattrs in the lbs_xattr field of the lsm_blob_sizes + * structure. + * Returns 0 if the requested slots in @xattrs have been successfully set, * -EOPNOTSUPP if no security attribute is needed, or * -ENOMEM on memory allocation failure. * @inode_init_security_anon: @@ -1624,6 +1628,7 @@ struct lsm_blob_sizes { int lbs_ipc; int lbs_msg_msg; int lbs_task; + int lbs_xattr; }; /* diff --git a/security/security.c b/security/security.c index e2857446fd32..36804609caaa 100644 --- a/security/security.c +++ b/security/security.c @@ -30,8 +30,6 @@ #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) @@ -210,6 +208,7 @@ 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. */ @@ -346,6 +345,7 @@ 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 @@ -1089,37 +1089,116 @@ 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; +} + 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 f553c370397e..57e5bc7c9ed8 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; @@ -6900,6 +6904,7 @@ 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 b6306d71c908..aa6ffa22bbba 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 attribute * * 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; @@ -4785,6 +4795,7 @@ 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 Thu Dec 1 10:41:24 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13061198 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 CD0BAC4321E for ; Thu, 1 Dec 2022 10:44:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229777AbiLAKoD (ORCPT ); Thu, 1 Dec 2022 05:44:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52050 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230482AbiLAKnO (ORCPT ); Thu, 1 Dec 2022 05:43:14 -0500 Received: from frasgout12.his.huawei.com (frasgout12.his.huawei.com [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D22792ADC; Thu, 1 Dec 2022 02:43:12 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.227]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4NNCDQ5pl7z9xFYD; Thu, 1 Dec 2022 18:36:38 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCHcm_phIhjrxuvAA--.49496S7; Thu, 01 Dec 2022 11:42:43 +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 v7 5/6] evm: Align evm_inode_init_security() definition with LSM infrastructure Date: Thu, 1 Dec 2022 11:41:24 +0100 Message-Id: <20221201104125.919483-6-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> References: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCHcm_phIhjrxuvAA--.49496S7 X-Coremail-Antispam: 1UD129KBjvJXoWxXF43tw1DXry7Kry5AF45Awb_yoWruw4rpa 13Ka4UCr1rJFyUWryFyF4xu3WSgFWrGr4UK393G34jyF1Dtr1xtrySyr15ury5X3y8GFnY qw42vr1rWwn8t3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI 42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z2 80aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07UZo7tUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgANBF1jj4IjiwADsT X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@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 | 20 +++++++++++++------- security/security.c | 5 ++--- 3 files changed, 21 insertions(+), 16 deletions(-) diff --git a/include/linux/evm.h b/include/linux/evm.h index aa63e0b3c0a2..3bb2ae9fe098 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -35,9 +35,9 @@ extern int evm_inode_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry, const char *xattr_name); extern void evm_inode_post_removexattr(struct dentry *dentry, const char *xattr_name); -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, @@ -108,9 +108,9 @@ static inline void evm_inode_post_removexattr(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 23d484e05e6f..0a312cafb7de 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -845,23 +845,29 @@ 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; + + for (xattr = xattrs; xattr->value != 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 36804609caaa..44ce579daec1 100644 --- a/security/security.c +++ b/security/security.c @@ -1190,9 +1190,8 @@ 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 Thu Dec 1 10:41:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13061199 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 28A6EC47088 for ; Thu, 1 Dec 2022 10:44:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230422AbiLAKof (ORCPT ); Thu, 1 Dec 2022 05:44:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230380AbiLAKnZ (ORCPT ); Thu, 1 Dec 2022 05:43:25 -0500 Received: from frasgout13.his.huawei.com (frasgout13.his.huawei.com [14.137.139.46]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8132EA13D2; Thu, 1 Dec 2022 02:43:21 -0800 (PST) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout13.his.huawei.com (SkyGuard) with ESMTP id 4NNCD34g9Rz9v7J7; Thu, 1 Dec 2022 18:36:19 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwCHcm_phIhjrxuvAA--.49496S8; Thu, 01 Dec 2022 11:42:52 +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 v7 6/6] evm: Support multiple LSMs providing an xattr Date: Thu, 1 Dec 2022 11:41:25 +0100 Message-Id: <20221201104125.919483-7-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> References: <20221201104125.919483-1-roberto.sassu@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: LxC2BwCHcm_phIhjrxuvAA--.49496S8 X-Coremail-Antispam: 1UD129KBjvJXoWxGryktFy8Jr45JrWUJFWfAFb_yoW5tFW5pa n8ta9rCrn5CFyUWr9IyF18uaySg3yrKw4UKwsxCr1jyFnrXrn2qryxtr15ur98Wr95Jrna yw40vw15Cw15t3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBvb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVWUCVW8JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv6xkF7I0E 14v26r4UJVWxJr1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrV C2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE 7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20x vY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I 3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_GFv_WrylIxkGc2Ij64vIr41lIx AIcVC0I7IYx2IY67AKxVWUCVW8JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJwCI 42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAIcVC2z2 80aVCY1x0267AKxVW8Jr0_Cr1UYxBIdaVFxhVjvjDU0xZFpf9x07UZo7tUUUUU= X-CM-SenderInfo: purev21wro2thvvxqx5xdzvxpfor3voofrz/1tbiAgANBF1jj4IjiwAEsU X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: selinux@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 f8b8c5004fc7..f799d72a59fa 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 708de9656bbd..68f99faac316 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 0a312cafb7de..1cf6871a0019 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); } @@ -851,14 +851,20 @@ 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; - for (xattr = xattrs; xattr->value != NULL; xattr++) - ; + for (xattr = xattrs; xattr->value != 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;