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@xxxxxxxxxxxxxxxx>
---
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 62783a923136..800040050032 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:
@@ -1598,7 +1598,7 @@ 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..b88a51b6ca41 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..3b77a0324c3d 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;
}
--
2.19.1
