diff mbox series

[46/58] LSM: Use lsm_context in release_secctx hooks

Message ID 20190531231020.628-47-casey@schaufler-ca.com (mailing list archive)
State New, archived
Headers show
Series LSM: Module stacking for AppArmor | expand

Commit Message

Casey Schaufler May 31, 2019, 11:10 p.m. UTC 
Convert SELinux, Smack and AppAror to use the lsm_context structure
instead of a context/secid pair. 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/lsm_hooks.h         | 3 +--
 security/apparmor/include/secid.h | 2 +-
 security/apparmor/secid.c         | 4 ++--
 security/security.c               | 6 +++++-
 security/selinux/hooks.c          | 4 ++--
 security/smack/smack_lsm.c        | 4 ++--
 6 files changed, 13 insertions(+), 10 deletions(-)

Comments

Kees Cook June 2, 2019, 2:27 a.m. UTC | #1 
On Fri, May 31, 2019 at 04:10:08PM -0700, Casey Schaufler wrote:
> -void apparmor_release_secctx(char *secdata, u32 seclen)
> +void apparmor_release_secctx(struct lsm_context *cp)
>  {
> -	kfree(secdata);
> +	kfree(cp->context);
>  }

Maybe better to have common helper?

void lsm_context_clear(struct lsm_context *cp)
{
    kfree(cp->context);
    cp->context = NULL;
    cp->len = 0;
}
Casey Schaufler June 3, 2019, 9:57 p.m. UTC | #2 
On 6/1/2019 7:27 PM, Kees Cook wrote:
> On Fri, May 31, 2019 at 04:10:08PM -0700, Casey Schaufler wrote:
>> -void apparmor_release_secctx(char *secdata, u32 seclen)
>> +void apparmor_release_secctx(struct lsm_context *cp)
>>  {
>> -	kfree(secdata);
>> +	kfree(cp->context);
>>  }
> Maybe better to have common helper?
>
> void lsm_context_clear(struct lsm_context *cp)
> {
>     kfree(cp->context);
>     cp->context = NULL;
>     cp->len = 0;
> }

The caller, security_release_secctx(), does a
lsm_context_init after the module specific code.
The helper wouldn't be generic, since Smack does
not do a kfree() on cp->context.
diff mbox series

Patch

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index d4ace7af4950..3a779a0f9e15 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1329,7 +1329,6 @@ 
  * @release_secctx:
  *	Release the security context.
  *	@secdata contains the security context.
- *	@seclen contains the length of the security context.
  *
  * Security hooks for Audit
  *
@@ -1663,7 +1662,7 @@  union security_list_options {
 	int (*secid_to_secctx)(struct lsm_export *l, struct lsm_context *cp);
 	int (*secctx_to_secid)(const struct lsm_context *cp,
 				struct lsm_export *l);
-	void (*release_secctx)(char *secdata, u32 seclen);
+	void (*release_secctx)(struct lsm_context *cp);
 
 	void (*inode_invalidate_secctx)(struct inode *inode);
 	int (*inode_notifysecctx)(struct inode *inode, struct lsm_context *cp);
diff --git a/security/apparmor/include/secid.h b/security/apparmor/include/secid.h
index acfcf99bff0e..a780e56d4f5b 100644
--- a/security/apparmor/include/secid.h
+++ b/security/apparmor/include/secid.h
@@ -29,7 +29,7 @@  struct aa_label *aa_secid_to_label(struct lsm_export *l);
 int apparmor_secid_to_secctx(struct lsm_export *l, struct lsm_context *cp);
 int apparmor_secctx_to_secid(const struct lsm_context *cp,
 			     struct lsm_export *l);
-void apparmor_release_secctx(char *secdata, u32 seclen);
+void apparmor_release_secctx(struct lsm_context *cp);
 
 
 int aa_alloc_secid(struct aa_label *label, gfp_t gfp);
diff --git a/security/apparmor/secid.c b/security/apparmor/secid.c
index 35df38592b6e..46c8b9a67ac7 100644
--- a/security/apparmor/secid.c
+++ b/security/apparmor/secid.c
@@ -123,9 +123,9 @@  int apparmor_secctx_to_secid(const struct lsm_context *cp, struct lsm_export *l)
 	return 0;
 }
 
-void apparmor_release_secctx(char *secdata, u32 seclen)
+void apparmor_release_secctx(struct lsm_context *cp)
 {
-	kfree(secdata);
+	kfree(cp->context);
 }
 
 /**
diff --git a/security/security.c b/security/security.c
index 44a4402073d7..029d2f4fe48c 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1996,7 +1996,11 @@  EXPORT_SYMBOL(security_secctx_to_secid);
 
 void security_release_secctx(char *secdata, u32 seclen)
 {
-	call_one_void_hook(release_secctx, secdata, seclen);
+	struct lsm_context lc;
+
+	lc.context = secdata;
+	lc.len = seclen;
+	call_one_void_hook(release_secctx, &lc);
 }
 EXPORT_SYMBOL(security_release_secctx);
 
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index fe09905d013c..332296f69f76 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6322,9 +6322,9 @@  static int selinux_secctx_to_secid(const struct lsm_context *cp,
 	return rc;
 }
 
-static void selinux_release_secctx(char *secdata, u32 seclen)
+static void selinux_release_secctx(struct lsm_context *cp)
 {
-	kfree(secdata);
+	kfree(cp->context);
 }
 
 static void selinux_inode_invalidate_secctx(struct inode *inode)
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 3d24503029e5..cf27905ccaa5 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4468,9 +4468,9 @@  static int smack_secctx_to_secid(const struct lsm_context *cp,
 }
 
 /*
- * There smack_release_secctx hook does nothing
+ * The smack_release_secctx hook does nothing
  */
-static void smack_release_secctx(char *secdata, u32 seclen)
+static void smack_release_secctx(struct lsm_context *cp)
 {
 }