From patchwork Thu Jul 11 11:18:49 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xu Kuohai X-Patchwork-Id: 13730483 X-Patchwork-Delegate: paul@paul-moore.com Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) (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 4A22916B392; Thu, 11 Jul 2024 11:14:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.56 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720696447; cv=none; b=n7AtKVriJHJ8Z3c3Qf9YFQAfPVzLMuwUusYZBNVA53sj9UWPIpNXMxpRp7bBiAPgHzYos6OSRLq7JOUDlM/s9F3usKv3YozSYx1A6iCgJF5sJuJ3IpuC2f7K/3zd9hkm5wZ+CVChFC00TUaqVAJjLltQg2k0e9Pakr7OffKe+ik= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720696447; c=relaxed/simple; bh=F2DBOYAey1NBHWQhzeFhHSb9csczr8YPT8WbPlwEQb8=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Q9qXJ8nuAWzDi1gG86V1vEtBhUpiB1e2CaoIn/ywzpq5K+I3e4ofbX3ZCUUeDJlKFgPL2BLDUgU94IG8XxtUCi0h05pQ4IGgin8ReBLQCxPGHGVGlG2Fg/yoAza3RtSSD/sjEZXFPmsGG00R3XItd4znS7mDRmgFxDEm5UHxmUk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com; spf=pass smtp.mailfrom=huaweicloud.com; arc=none smtp.client-ip=45.249.212.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=huaweicloud.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huaweicloud.com Received: from mail.maildlp.com (unknown [172.19.93.142]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4WKXCr713pz4f3jrw; Thu, 11 Jul 2024 19:13:44 +0800 (CST) Received: from mail02.huawei.com (unknown [10.116.40.128]) by mail.maildlp.com (Postfix) with ESMTP id 9C8D41A0187; Thu, 11 Jul 2024 19:13:56 +0800 (CST) Received: from k01.huawei.com (unknown [10.67.174.197]) by APP4 (Coremail) with SMTP id gCh0CgCHjPVxvo9mulQgBw--.25300S3; Thu, 11 Jul 2024 19:13:56 +0800 (CST) From: Xu Kuohai To: bpf@vger.kernel.org, netdev@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-integrity@vger.kernel.org, apparmor@lists.ubuntu.com, selinux@vger.kernel.org Cc: Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Martin KaFai Lau , Eduard Zingerman , Song Liu , Yonghong Song , John Fastabend , KP Singh , Stanislav Fomichev , Hao Luo , Jiri Olsa , Matt Bobrowski , Brendan Jackman , Paul Moore , James Morris , "Serge E . Hallyn" , Khadija Kamran , Casey Schaufler , Ondrej Mosnacek , Kees Cook , John Johansen , Lukas Bulwahn , Roberto Sassu , Shung-Hsi Yu , Edward Cree , Alexander Viro , Christian Brauner , Trond Myklebust , Anna Schumaker , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Stephen Smalley Subject: [PATCH bpf-next v4 01/20] lsm: Refactor return value of LSM hook vm_enough_memory Date: Thu, 11 Jul 2024 19:18:49 +0800 Message-Id: <20240711111908.3817636-2-xukuohai@huaweicloud.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20240711111908.3817636-1-xukuohai@huaweicloud.com> References: <20240711111908.3817636-1-xukuohai@huaweicloud.com> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgCHjPVxvo9mulQgBw--.25300S3 X-Coremail-Antispam: 1UD129KBjvJXoWxur48GF1DAw17Kr47ur1rWFg_yoW7Gr4kpF s5Ka13KrWvkFyxZrs7GanxC3W3t34fWF4UGrWUu34Fk3ZFvr17KF4UAw1Y9r1UtrW8tasF qFW29rs3Ca1qq37anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBFb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8Jr0_Cr1UM28EF7xvwVC2z280aVAFwI0_GcCE3s1l84ACjcxK6I8E87Iv6xkF7I0E14v2 6rxl6s0DM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMc Ij6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8JwAm72CE4IkC6x0Yz7v_ Jr0_Gr1lF7xvr2IYc2Ij64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l42xK82IYc2Ij64 vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8G jcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26rWY6r4UJwCIc40Y0x0EwIxGrwCI42IY6x IIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVWxJVW8Jr1lIxAIcVCF 04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7 CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07UAHUDUUUUU= X-CM-SenderInfo: 50xn30hkdlqx5xdzvxpfor3voofrz/ From: Xu Kuohai To be consistent with most LSM hooks, convert the return value of hook vm_enough_memory to 0 or a negative error code. Before: - Hook vm_enough_memory returns 1 if permission is granted, 0 if not. - LSM_RET_DEFAULT(vm_enough_memory_mm) is 1. After: - Hook vm_enough_memory reutrns 0 if permission is granted, negative error code if not. - LSM_RET_DEFAULT(vm_enough_memory_mm) is 0. Signed-off-by: Xu Kuohai --- include/linux/lsm_hook_defs.h | 2 +- include/linux/security.h | 2 +- security/commoncap.c | 11 +++-------- security/security.c | 11 +++++------ security/selinux/hooks.c | 15 ++++----------- 5 files changed, 14 insertions(+), 27 deletions(-) diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h index 44488b1ab9a9..e6e6f8473955 100644 --- a/include/linux/lsm_hook_defs.h +++ b/include/linux/lsm_hook_defs.h @@ -48,7 +48,7 @@ LSM_HOOK(int, 0, quota_on, struct dentry *dentry) LSM_HOOK(int, 0, syslog, int type) LSM_HOOK(int, 0, settime, const struct timespec64 *ts, const struct timezone *tz) -LSM_HOOK(int, 1, vm_enough_memory, struct mm_struct *mm, long pages) +LSM_HOOK(int, 0, vm_enough_memory, struct mm_struct *mm, long pages) LSM_HOOK(int, 0, bprm_creds_for_exec, struct linux_binprm *bprm) LSM_HOOK(int, 0, bprm_creds_from_file, struct linux_binprm *bprm, const struct file *file) LSM_HOOK(int, 0, bprm_check_security, struct linux_binprm *bprm) diff --git a/include/linux/security.h b/include/linux/security.h index de3af33e6ff5..454f96307cb9 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -634,7 +634,7 @@ static inline int security_settime64(const struct timespec64 *ts, static inline int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) { - return __vm_enough_memory(mm, pages, cap_vm_enough_memory(mm, pages)); + return __vm_enough_memory(mm, pages, !cap_vm_enough_memory(mm, pages)); } static inline int security_bprm_creds_for_exec(struct linux_binprm *bprm) diff --git a/security/commoncap.c b/security/commoncap.c index 162d96b3a676..cefad323a0b1 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -1396,17 +1396,12 @@ int cap_task_prctl(int option, unsigned long arg2, unsigned long arg3, * Determine whether the allocation of a new virtual mapping by the current * task is permitted. * - * Return: 1 if permission is granted, 0 if not. + * Return: 0 if permission granted, negative error code if not. */ int cap_vm_enough_memory(struct mm_struct *mm, long pages) { - int cap_sys_admin = 0; - - if (cap_capable(current_cred(), &init_user_ns, - CAP_SYS_ADMIN, CAP_OPT_NOAUDIT) == 0) - cap_sys_admin = 1; - - return cap_sys_admin; + return cap_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN, + CAP_OPT_NOAUDIT); } /** diff --git a/security/security.c b/security/security.c index e5ca08789f74..3475f0cab3da 100644 --- a/security/security.c +++ b/security/security.c @@ -1115,15 +1115,14 @@ int security_vm_enough_memory_mm(struct mm_struct *mm, long pages) int rc; /* - * The module will respond with a positive value if - * it thinks the __vm_enough_memory() call should be - * made with the cap_sys_admin set. If all of the modules - * agree that it should be set it will. If any module - * thinks it should not be set it won't. + * The module will respond with 0 if it thinks the __vm_enough_memory() + * call should be made with the cap_sys_admin set. If all of the modules + * agree that it should be set it will. If any module thinks it should + * not be set it won't. */ hlist_for_each_entry(hp, &security_hook_heads.vm_enough_memory, list) { rc = hp->hook.vm_enough_memory(mm, pages); - if (rc <= 0) { + if (rc < 0) { cap_sys_admin = 0; break; } diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 7eed331e90f0..9cd5a8f1f6a3 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2202,23 +2202,16 @@ static int selinux_syslog(int type) } /* - * Check that a process has enough memory to allocate a new virtual - * mapping. 0 means there is enough memory for the allocation to - * succeed and -ENOMEM implies there is not. + * Check permission for allocating a new virtual mapping. Returns + * 0 if permission is granted, negative error code if not. * * Do not audit the selinux permission check, as this is applied to all * processes that allocate mappings. */ static int selinux_vm_enough_memory(struct mm_struct *mm, long pages) { - int rc, cap_sys_admin = 0; - - rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN, - CAP_OPT_NOAUDIT, true); - if (rc == 0) - cap_sys_admin = 1; - - return cap_sys_admin; + return cred_has_capability(current_cred(), CAP_SYS_ADMIN, + CAP_OPT_NOAUDIT, true); } /* binprm security operations */