[PATCH 14/58] LSM: Use lsm_export in security_kernel_act_as

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, keescook@chromium.org,
	john.johansen@canonical.com, penguin-kernel@i-love.sakura.ne.jp,
	paul@paul-moore.com, sds@tycho.nsa.gov
Subject: [PATCH 14/58] LSM: Use lsm_export in security_kernel_act_as
Date: Fri, 31 May 2019 16:31:05 -0700	[thread overview]
Message-ID: <20190531233149.715-15-casey@schaufler-ca.com> (raw)
In-Reply-To: <20190531233149.715-1-casey@schaufler-ca.com>

From: Casey Schaufler <cschaufler@schaufler-ca.com>

Convert security_kernel_act_as to use the lsm_export structure
instead of a u32 secid. There is some scaffolding involved
that will be removed when the related data is updated.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/cred.h     |  3 ++-
 include/linux/security.h |  5 +++--
 kernel/cred.c            | 10 ++++++----
 security/security.c      |  8 ++------
 4 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/include/linux/cred.h b/include/linux/cred.h
index efb6edf32de7..9305298eca17 100644
--- a/include/linux/cred.h
+++ b/include/linux/cred.h
@@ -22,6 +22,7 @@
 
 struct cred;
 struct inode;
+struct lsm_export;
 
 /*
  * COW Supplementary groups list
@@ -165,7 +166,7 @@ extern const struct cred *override_creds(const struct cred *);
 extern void revert_creds(const struct cred *);
 extern struct cred *prepare_kernel_cred(struct task_struct *);
 extern int change_create_files_as(struct cred *, struct inode *);
-extern int set_security_override(struct cred *, u32);
+extern int set_security_override(struct cred *, struct lsm_export *);
 extern int set_security_override_from_ctx(struct cred *, const char *);
 extern int set_create_files_as(struct cred *, struct inode *);
 extern int cred_fscmp(const struct cred *, const struct cred *);
diff --git a/include/linux/security.h b/include/linux/security.h
index ea2c6c4e88db..7369cdc3a681 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -378,7 +378,7 @@ void security_cred_free(struct cred *cred);
 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
 void security_transfer_creds(struct cred *new, const struct cred *old);
 void security_cred_getsecid(const struct cred *c, u32 *secid);
-int security_kernel_act_as(struct cred *new, u32 secid);
+int security_kernel_act_as(struct cred *new, struct lsm_export *l);
 int security_kernel_create_files_as(struct cred *new, struct inode *inode);
 int security_kernel_module_request(char *kmod_name);
 int security_kernel_load_data(enum kernel_load_data_id id);
@@ -961,7 +961,8 @@ static inline void security_transfer_creds(struct cred *new,
 {
 }
 
-static inline int security_kernel_act_as(struct cred *cred, u32 secid)
+static inline int security_kernel_act_as(struct cred *cred,
+					 struct lsm_export *l)
 {
 	return 0;
 }
diff --git a/kernel/cred.c b/kernel/cred.c
index 45d77284aed0..40a3fde22667 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -701,14 +701,14 @@ EXPORT_SYMBOL(prepare_kernel_cred);
 /**
  * set_security_override - Set the security ID in a set of credentials
  * @new: The credentials to alter
- * @secid: The LSM security ID to set
+ * @l: The LSM security information to set
  *
  * Set the LSM security ID in a set of credentials so that the subjective
  * security is overridden when an alternative set of credentials is used.
  */
-int set_security_override(struct cred *new, u32 secid)
+int set_security_override(struct cred *new, struct lsm_export *l)
 {
-	return security_kernel_act_as(new, secid);
+	return security_kernel_act_as(new, l);
 }
 EXPORT_SYMBOL(set_security_override);
 
@@ -724,6 +724,7 @@ EXPORT_SYMBOL(set_security_override);
  */
 int set_security_override_from_ctx(struct cred *new, const char *secctx)
 {
+	struct lsm_export le;
 	u32 secid;
 	int ret;
 
@@ -731,7 +732,8 @@ int set_security_override_from_ctx(struct cred *new, const char *secctx)
 	if (ret < 0)
 		return ret;
 
-	return set_security_override(new, secid);
+	lsm_export_to_all(&le, secid);
+	return set_security_override(new, &le);
 }
 EXPORT_SYMBOL(set_security_override_from_ctx);
 
diff --git a/security/security.c b/security/security.c
index 1e819ecf26ff..edaaaef54239 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1615,13 +1615,9 @@ void security_cred_getsecid(const struct cred *c, u32 *secid)
 }
 EXPORT_SYMBOL(security_cred_getsecid);
 
-int security_kernel_act_as(struct cred *new, u32 secid)
+int security_kernel_act_as(struct cred *new, struct lsm_export *l)
 {
-	struct lsm_export data = { .flags = LSM_EXPORT_NONE };
-
-	lsm_export_to_all(&data, secid);
-
-	return call_int_hook(kernel_act_as, 0, new, &data);
+	return call_int_hook(kernel_act_as, 0, new, l);
 }
 
 int security_kernel_create_files_as(struct cred *new, struct inode *inode)
-- 
2.19.1

