[08/59] LSM: Use lsm_export in the kernel_ask_as hooks

Message ID	20190409213946.1667-9-casey@schaufler-ca.com (mailing list archive)
State	Not Applicable
Headers	show Return-Path: <selinux-owner@kernel.org> From: Casey Schaufler <casey@schaufler-ca.com> To: casey.schaufler@intel.com, jmorris@namei.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Cc: casey@schaufler-ca.com Subject: [PATCH 08/59] LSM: Use lsm_export in the kernel_ask_as hooks Date: Tue, 9 Apr 2019 14:38:55 -0700 Message-Id: <20190409213946.1667-9-casey@schaufler-ca.com> In-Reply-To: <20190409213946.1667-1-casey@schaufler-ca.com> References: <20190409213946.1667-1-casey@schaufler-ca.com> Sender: selinux-owner@vger.kernel.org Precedence: bulk
Series	LSM: Module stacking for AppArmor \| expand [00/59] LSM: Module stacking for AppArmor [01/59] LSM: Infrastructure management of the superblock [02/59] LSM: Infrastructure management of the sock security [03/59] LSM: Infrastructure management of the key security blob [04/59] LSM: Create an lsm_export data structure. [05/59] LSM: Use lsm_export in the inode_getsecid hooks [06/59] LSM: Use lsm_export in the cred_getsecid hooks [07/59] LSM: Use lsm_export in the ipc_getsecid and task_getsecid hooks [08/59] LSM: Use lsm_export in the kernel_ask_as hooks [09/59] LSM: Use lsm_export in the getpeersec_dgram hooks [10/59] LSM: Use lsm_export in the audit_rule_match hooks [11/59] LSM: Fix logical operation in lsm_export checks [12/59] LSM: Use lsm_export in the secid_to_secctx hooks [13/59] LSM: Use lsm_export in the secctx_to_secid hooks [14/59] LSM: Use lsm_export in security_audit_rule_match [15/59] LSM: Use lsm_export in security_kernel_act_as [16/59] LSM: Use lsm_export in security_socket_getpeersec_dgram [17/59] LSM: Use lsm_export in security_secctx_to_secid [18/59] LSM: Use lsm_export in security_secid_to_secctx [19/59] LSM: Use lsm_export in security_ipc_getsecid [20/59] LSM: Use lsm_export in security_task_getsecid [21/59] LSM: Use lsm_export in security_inode_getsecid [22/59] LSM: Use lsm_export in security_cred_getsecid [23/59] Audit: Change audit_sig_sid to audit_sig_lsm [24/59] Audit: Convert target_sid to an lsm_export structure [25/59] Audit: Convert osid to an lsm_export structure [26/59] IMA: Clean out lsm_export scaffolding [27/59] NET: Store LSM access information in the socket blob for UDS [28/59] NET: Remove scaffolding on secmarks [29/59] NET: Remove scaffolding on new secmarks [30/59] NET: Remove netfilter scaffolding for lsm_export [31/59] Netlabel: Replace secids with lsm_export [32/59] LSM: Remove lsm_export scaffolding functions [33/59] IMA: FIXUP prototype using lsm_export [34/59] Smack: Restore the release_secctx hook [35/59] AppArmor: Remove unnecessary hook stub [36/59] LSM: Limit calls to certain module hooks [37/59] LSM: Create a data structure for a security context [38/59] LSM: Use lsm_context in secid_to_secctx hooks [39/59] LSM: Use lsm_context in secctx_to_secid hooks [40/59] LSM: Use lsm_context in inode_getsecctx hooks [41/59] LSM: Use lsm_context in inode_notifysecctx hooks [42/59] LSM: Use lsm_context in dentry_init_security hooks [43/59] LSM: Use lsm_context in security_dentry_init_security [44/59] LSM: Use lsm_context in security_inode_notifysecctx [45/59] LSM: Use lsm_context in security_inode_getsecctx [46/59] LSM: Use lsm_context in security_secctx_to_secid [47/59] LSM: Use lsm_context in release_secctx hooks [48/59] LSM: Use lsm_context in security_release_secctx [49/59] LSM: Use lsm_context in security_secid_to_secctx [50/59] fs: remove lsm_context scaffolding [51/59] LSM: Add the release function to the lsm_context [52/59] LSM: Use lsm_context in inode_setsecctx hooks [53/59] LSM: Use lsm_context in security_inode_setsecctx [54/59] kernfs: remove lsm_context scaffolding [55/59] LSM: Remove unused macro [56/59] LSM: Special handling for secctx lsm hooks [57/59] SELinux: Use blob offset in current_sid [58/59] LSM: Specify which LSM to display with /proc/self/attr/display [59/59] AppArmor: Remove the exclusive flag

Message ID

20190409213946.1667-9-casey@schaufler-ca.com (mailing list archive)

State

Not Applicable

Headers

From: Casey Schaufler <casey@schaufler-ca.com>
To: casey.schaufler@intel.com, jmorris@namei.org,
        linux-security-module@vger.kernel.org, selinux@vger.kernel.org
Cc: casey@schaufler-ca.com
Subject: [PATCH 08/59] LSM: Use lsm_export in the kernel_ask_as hooks
Date: Tue,  9 Apr 2019 14:38:55 -0700
Message-Id: <20190409213946.1667-9-casey@schaufler-ca.com>
In-Reply-To: <20190409213946.1667-1-casey@schaufler-ca.com>
References: <20190409213946.1667-1-casey@schaufler-ca.com>
Sender: selinux-owner@vger.kernel.org
Precedence: bulk

Series

LSM: Module stacking for AppArmor | expand

Commit Message

Casey Schaufler April 9, 2019, 9:38 p.m. UTC

Convert the kernel_ask_as hooks to use the lsm_export
structure instead of a u32 secid. There is some scaffolding
involved that will be removed when security_kernel_ask_as()
is updated.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/lsm_hooks.h  |  4 ++--
 security/security.c        | 15 ++++++++++++++-
 security/selinux/hooks.c   | 17 ++++++++++++++---
 security/smack/smack_lsm.c | 12 +++++++++++-
 4 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 544671f44dfa..85b8217ce2f2 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -578,7 +578,7 @@ 
  * @kernel_act_as:
  *	Set the credentials for a kernel service to act as (subjective context).
  *	@new points to the credentials to be modified.
- *	@secid specifies the security ID to be set
+ *	@l specifies the security data to be set
  *	The current task must be the one that nominated @secid.
  *	Return 0 if successful.
  * @kernel_create_files_as:
@@ -1606,7 +1606,7 @@  union security_list_options {
 				gfp_t gfp);
 	void (*cred_transfer)(struct cred *new, const struct cred *old);
 	void (*cred_getsecid)(const struct cred *c, struct lsm_export *l);
-	int (*kernel_act_as)(struct cred *new, u32 secid);
+	int (*kernel_act_as)(struct cred *new, struct lsm_export *l);
 	int (*kernel_create_files_as)(struct cred *new, struct inode *inode);
 	int (*kernel_module_request)(char *kmod_name);
 	int (*kernel_load_data)(enum kernel_load_data_id id);
diff --git a/security/security.c b/security/security.c
index 802557ff6f60..3a766755b722 100644
--- a/security/security.c
+++ b/security/security.c
@@ -742,6 +742,15 @@  static inline void lsm_export_secid(struct lsm_export *data, u32 *secid)
 	}
 }
 
+static inline void lsm_export_to_all(struct lsm_export *data, u32 secid)
+{
+	data->selinux = secid;
+	data->smack = secid;
+	data->apparmor = secid;
+	data->flags = LSM_EXPORT_SELINUX | LSM_EXPORT_SMACK |
+		      LSM_EXPORT_APPARMOR;
+}
+
 /* Security operations */
 
 int security_binder_set_context_mgr(struct task_struct *mgr)
@@ -1647,7 +1656,11 @@  EXPORT_SYMBOL(security_cred_getsecid);
 
 int security_kernel_act_as(struct cred *new, u32 secid)
 {
-	return call_int_hook(kernel_act_as, 0, new, secid);
+	struct lsm_export data = { .flags = LSM_EXPORT_NONE };
+
+	lsm_export_to_all(&data, secid);
+
+	return call_int_hook(kernel_act_as, 0, new, &data);
 }
 
 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index c82108793fb5..8d4334f68a65 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -222,6 +222,14 @@  static inline void selinux_export_secid(struct lsm_export *l, u32 secid)
 	l->flags |= LSM_EXPORT_SELINUX;
 }
 
+static inline void selinux_import_secid(struct lsm_export *l, u32 *secid)
+{
+	if (l->flags | LSM_EXPORT_SELINUX)
+		*secid = l->selinux;
+	else
+		*secid = SECSID_NULL;
+}
+
 /*
  * get the security ID of a set of credentials
  */
@@ -3773,19 +3781,22 @@  static void selinux_cred_getsecid(const struct cred *c, struct lsm_export *l)
  * set the security data for a kernel service
  * - all the creation contexts are set to unlabelled
  */
-static int selinux_kernel_act_as(struct cred *new, u32 secid)
+static int selinux_kernel_act_as(struct cred *new, struct lsm_export *l)
 {
 	struct task_security_struct *tsec = selinux_cred(new);
+	u32 nsid;
 	u32 sid = current_sid();
 	int ret;
 
+	selinux_import_secid(l, &nsid);
+
 	ret = avc_has_perm(&selinux_state,
-			   sid, secid,
+			   sid, nsid,
 			   SECCLASS_KERNEL_SERVICE,
 			   KERNEL_SERVICE__USE_AS_OVERRIDE,
 			   NULL);
 	if (ret == 0) {
-		tsec->sid = secid;
+		tsec->sid = nsid;
 		tsec->create_sid = 0;
 		tsec->keycreate_sid = 0;
 		tsec->sockcreate_sid = 0;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 13ac3045a388..da85d607d40a 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -475,6 +475,14 @@  static inline void smack_export_secid(struct lsm_export *l, u32 secid)
 	l->flags |= LSM_EXPORT_SMACK;
 }
 
+static inline void smack_import_secid(struct lsm_export *l, u32 *secid)
+{
+	if (l->flags | LSM_EXPORT_SMACK)
+		*secid = l->smack;
+	else
+		*secid = 0;
+}
+
 /*
  * LSM hooks.
  * We he, that is fun!
@@ -1997,10 +2005,12 @@  static void smack_cred_getsecid(const struct cred *cred, struct lsm_export *l)
  *
  * Set the security data for a kernel service.
  */
-static int smack_kernel_act_as(struct cred *new, u32 secid)
+static int smack_kernel_act_as(struct cred *new, struct lsm_export *l)
 {
+	u32 secid;
 	struct task_smack *new_tsp = smack_cred(new);
 
+	smack_import_secid(l, &secid);
 	new_tsp->smk_task = smack_from_secid(secid);
 	return 0;
 }

[08/59] LSM: Use lsm_export in the kernel_ask_as hooks

Commit Message

Patch