apparmor: use common fn to clear task_context for domain transitions

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Steve Beattie <sbeattie@ubuntu.com>

3 files changed, 20 insertions, 16 deletions

diff --git a/security/apparmor/context.c b/security/apparmor/context.c
index 611e6ce70b03..3f911afa2bb9 100644
--- a/security/apparmor/context.c
+++ b/security/apparmor/context.c
@@ -105,16 +105,12 @@ int aa_replace_current_profile(struct aa_profile *profile)
                 return -ENOMEM;
 
         cxt = new->security;
-        if (unconfined(profile) || (cxt->profile->ns != profile->ns)) {
+        if (unconfined(profile) || (cxt->profile->ns != profile->ns))
                 /* if switching to unconfined or a different profile namespace
                  * clear out context state
                  */
-                aa_put_profile(cxt->previous);
-                aa_put_profile(cxt->onexec);
-                cxt->previous = NULL;
-                cxt->onexec = NULL;
-                cxt->token = 0;
-        }
+                aa_clear_task_cxt_trans(cxt);
+
         /* be careful switching cxt->profile, when racing replacement it
          * is possible that cxt->profile->replacedby is the reference keeping
          * @profile valid, so make sure to get its reference before dropping
@@ -222,11 +218,10 @@ int aa_restore_previous_profile(u64 token)
                 aa_get_profile(cxt->profile);
                 aa_put_profile(cxt->previous);
         }
-        /* clear exec && prev information when restoring to previous context */
+        /* ref has been transfered so avoid putting ref in clear_task_cxt */
         cxt->previous = NULL;
-        cxt->token = 0;
-        aa_put_profile(cxt->onexec);
-        cxt->onexec = NULL;
+        /* clear exec && prev information when restoring to previous context */
+        aa_clear_task_cxt_trans(cxt);
 
         commit_creds(new);
         return 0;
diff --git a/security/apparmor/domain.c b/security/apparmor/domain.c
index fb47d5b71ea6..07fcb09b990f 100644
--- a/security/apparmor/domain.c
+++ b/security/apparmor/domain.c
@@ -512,11 +512,7 @@ x_clear:
         cxt->profile = new_profile;
 
         /* clear out all temporary/transitional state from the context */
-        aa_put_profile(cxt->previous);
-        aa_put_profile(cxt->onexec);
-        cxt->previous = NULL;
-        cxt->onexec = NULL;
-        cxt->token = 0;
+        aa_clear_task_cxt_trans(cxt);
 
 audit:
         error = aa_audit_file(profile, &perms, GFP_KERNEL, OP_EXEC, MAY_EXEC,
diff --git a/security/apparmor/include/context.h b/security/apparmor/include/context.h
index 1e9443a58877..4cecad313227 100644
--- a/security/apparmor/include/context.h
+++ b/security/apparmor/include/context.h
@@ -160,4 +160,17 @@ static inline struct aa_profile *aa_current_profile(void)
         return profile;
 }
 
+/**
+ * aa_clear_task_cxt_trans - clear transition tracking info from the cxt
+ * @cxt: task context to clear (NOT NULL)
+ */
+static inline void aa_clear_task_cxt_trans(struct aa_task_cxt *cxt)
+{
+        aa_put_profile(cxt->previous);
+        aa_put_profile(cxt->onexec);
+        cxt->previous = NULL;
+        cxt->onexec = NULL;
+        cxt->token = 0;
+}
+
 #endif /* __AA_CONTEXT_H */