cred: add get_cred_many and put_cred_many

[linux-block.git] / kernel / cred.c

diff --git a/kernel/cred.c b/kernel/cred.c
index 98cb4eca23fb2fb2722b9e5d00d4a3f8ab51fd23..9398e534b997b8370012bfac7ff3893bba0f102a 100644 (file)
--- a/kernel/cred.c
+++ b/kernel/cred.c
@@ -162,23 +162,29 @@ EXPORT_SYMBOL(__put_cred);
  */
 void exit_creds(struct task_struct *tsk)
 {
-       struct cred *cred;
+       struct cred *real_cred, *cred;
 
        kdebug("exit_creds(%u,%p,%p,{%d,%d})", tsk->pid, tsk->real_cred, tsk->cred,
               atomic_read(&tsk->cred->usage),
               read_cred_subscribers(tsk->cred));
 
-       cred = (struct cred *) tsk->real_cred;
+       real_cred = (struct cred *) tsk->real_cred;
        tsk->real_cred = NULL;
-       validate_creds(cred);
-       alter_cred_subscribers(cred, -1);
-       put_cred(cred);
 
        cred = (struct cred *) tsk->cred;
        tsk->cred = NULL;
+
        validate_creds(cred);
-       alter_cred_subscribers(cred, -1);
-       put_cred(cred);
+       if (real_cred == cred) {
+               alter_cred_subscribers(cred, -2);
+               put_cred_many(cred, 2);
+       } else {
+               validate_creds(real_cred);
+               alter_cred_subscribers(real_cred, -1);
+               put_cred(real_cred);
+               alter_cred_subscribers(cred, -1);
+               put_cred(cred);
+       }
 
 #ifdef CONFIG_KEYS_REQUEST_CACHE
        key_put(tsk->cached_requested_key);
@@ -355,8 +361,7 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
 #endif
                clone_flags & CLONE_THREAD
            ) {
-               p->real_cred = get_cred(p->cred);
-               get_cred(p->cred);
+               p->real_cred = get_cred_many(p->cred, 2);
                alter_cred_subscribers(p->cred, 2);
                kdebug("share_creds(%p{%d,%d})",
                       p->cred, atomic_read(&p->cred->usage),
@@ -520,8 +525,7 @@ int commit_creds(struct cred *new)
                proc_id_connector(task, PROC_EVENT_GID);
 
        /* release the old obj and subj refs both */
-       put_cred(old);
-       put_cred(old);
+       put_cred_many(old, 2);
        return 0;
 }
 EXPORT_SYMBOL(commit_creds);