From patchwork Sat Jun 10 07:57:37 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roberto Sassu X-Patchwork-Id: 13274763 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3986BBA20 for ; Sat, 10 Jun 2023 07:59:08 +0000 (UTC) Received: from frasgout12.his.huawei.com (unknown [14.137.139.154]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D31E3A86; Sat, 10 Jun 2023 00:59:02 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.18.147.228]) by frasgout12.his.huawei.com (SkyGuard) with ESMTP id 4QdVQY13Jdz9xFrN; Sat, 10 Jun 2023 15:47:01 +0800 (CST) Received: from huaweicloud.com (unknown [10.204.63.22]) by APP1 (Coremail) with SMTP id LxC2BwBH0AsGLYRklC8oAw--.4566S5; Sat, 10 Jun 2023 08:58:36 +0100 (CET) From: Roberto Sassu To: zohar@linux.ibm.com, dmitry.kasatkin@gmail.com, paul@paul-moore.com, jmorris@namei.org, serge@hallyn.com, stephen.smalley.work@gmail.com, eparis@parisplace.org, casey@schaufler-ca.com Cc: linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, bpf@vger.kernel.org, kpsingh@kernel.org, keescook@chromium.org, nicolas.bouchinet@clip-os.org, Roberto Sassu Subject: [PATCH v12 3/4] evm: Align evm_inode_init_security() definition with LSM infrastructure Date: Sat, 10 Jun 2023 09:57:37 +0200 Message-Id: <20230610075738.3273764-4-roberto.sassu@huaweicloud.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230610075738.3273764-1-roberto.sassu@huaweicloud.com> References: <20230610075738.3273764-1-roberto.sassu@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: LxC2BwBH0AsGLYRklC8oAw--.4566S5 X-Coremail-Antispam: 1UD129KBjvJXoWxXF43tw1kKw15Kr1kur48WFg_yoWrCF1xpF Zxt3WUCr1rJFyUWryFyF47u3WSgFWrGr4Dt393G34jyF1Dtr1xtFW0yr15uryrXrW8JrnY qw429r1rWwn0y3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 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/1tbiAgAEBF1jj4qCJAABse X-CFilter-Loop: Reflected X-Spam-Status: No, score=-0.9 required=5.0 tests=BAYES_00,KHOP_HELO_FCRDNS, MAY_BE_FORGED,PDS_RDNS_DYNAMIC_FP,RDNS_DYNAMIC,SPF_HELO_NONE,SPF_NONE, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net 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 the xattr array allocated by security_inode_init_security(), and the number of xattrs filled by previously invoked LSMs. Use the newly introduced lsm_get_xattr_slot() to position EVM correctly in the xattrs array, like a regular LSM, and to increment the number of filled slots. For now, the LSM infrastructure allocates enough xattrs slots to store the EVM xattr, without using the reservation mechanism. Signed-off-by: Roberto Sassu Reviewed-by: Mimi Zohar Acked-by: Mimi Zohar --- include/linux/evm.h | 14 ++++++++------ security/integrity/evm/evm_main.c | 16 ++++++++++------ security/security.c | 4 ++-- 3 files changed, 20 insertions(+), 14 deletions(-) diff --git a/include/linux/evm.h b/include/linux/evm.h index 7dc1ee74169..01fc495a83e 100644 --- a/include/linux/evm.h +++ b/include/linux/evm.h @@ -56,9 +56,10 @@ 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); + +int evm_inode_init_security(struct inode *inode, struct inode *dir, + const struct qstr *qstr, struct xattr *xattrs, + int *xattr_count); 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 +158,10 @@ 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, + int *xattr_count) { return 0; } diff --git a/security/integrity/evm/evm_main.c b/security/integrity/evm/evm_main.c index cf24c525558..475196ce712 100644 --- a/security/integrity/evm/evm_main.c +++ b/security/integrity/evm/evm_main.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include @@ -864,23 +865,26 @@ 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, + int *xattr_count) { struct evm_xattr *xattr_data; + struct xattr *evm_xattr; int rc; - if (!(evm_initialized & EVM_INIT_HMAC) || - !evm_protected_xattr(lsm_xattr->name)) + if (!(evm_initialized & EVM_INIT_HMAC) || !xattrs || + !evm_protected_xattr(xattrs->name)) return 0; + evm_xattr = lsm_get_xattr_slot(xattrs, xattr_count); + 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 d5ef7df1ce4..819294d91ad 100644 --- a/security/security.c +++ b/security/security.c @@ -1645,8 +1645,8 @@ int security_inode_init_security(struct inode *inode, struct inode *dir, if (!xattr_count) goto out; - ret = evm_inode_init_security(inode, new_xattrs, - &new_xattrs[xattr_count]); + ret = evm_inode_init_security(inode, dir, qstr, new_xattrs, + &xattr_count); if (ret) goto out; ret = initxattrs(inode, new_xattrs, fs_data);