Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

[firefly-linux-kernel-4.4.55.git] / security / keys / keyctl.c

diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
index 0f5b3f0272995dc7057f1306c346468174d3e464..3364fbf46807bb384e61a761f2f6f2fab9ebb888 100644 (file)
--- a/security/keys/keyctl.c
+++ b/security/keys/keyctl.c
@@ -1106,7 +1106,7 @@ long keyctl_instantiate_key_iov(key_serial_t id,
        struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
        long ret;
 
-       if (_payload_iov == 0 || ioc == 0)
+       if (!_payload_iov || !ioc)
                goto no_payload;
 
        ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc,
@@ -1456,7 +1456,7 @@ long keyctl_session_to_parent(void)
 {
        struct task_struct *me, *parent;
        const struct cred *mycred, *pcred;
-       struct task_work *newwork, *oldwork;
+       struct callback_head *newwork, *oldwork;
        key_ref_t keyring_r;
        struct cred *cred;
        int ret;
@@ -1466,19 +1466,17 @@ long keyctl_session_to_parent(void)
                return PTR_ERR(keyring_r);
 
        ret = -ENOMEM;
-       newwork = kmalloc(sizeof(struct task_work), GFP_KERNEL);
-       if (!newwork)
-               goto error_keyring;
 
        /* our parent is going to need a new cred struct, a new tgcred struct
         * and new security data, so we allocate them here to prevent ENOMEM in
         * our parent */
        cred = cred_alloc_blank();
        if (!cred)
-               goto error_newwork;
+               goto error_keyring;
+       newwork = &cred->rcu;
 
        cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r);
-       init_task_work(newwork, key_change_session_keyring, cred);
+       init_task_work(newwork, key_change_session_keyring);
 
        me = current;
        rcu_read_lock();
@@ -1488,6 +1486,7 @@ long keyctl_session_to_parent(void)
        oldwork = NULL;
        parent = me->real_parent;
 
+       task_lock(parent);
        /* the parent mustn't be init and mustn't be a kernel thread */
        if (parent->pid <= 1 || !parent->mm)
                goto unlock;
@@ -1531,20 +1530,15 @@ long keyctl_session_to_parent(void)
        if (!ret)
                newwork = NULL;
 unlock:
+       task_unlock(parent);
        write_unlock_irq(&tasklist_lock);
        rcu_read_unlock();
-       if (oldwork) {
-               put_cred(oldwork->data);
-               kfree(oldwork);
-       }
-       if (newwork) {
-               put_cred(newwork->data);
-               kfree(newwork);
-       }
+       if (oldwork)
+               put_cred(container_of(oldwork, struct cred, rcu));
+       if (newwork)
+               put_cred(cred);
        return ret;
 
-error_newwork:
-       kfree(newwork);
 error_keyring:
        key_ref_put(keyring_r);
        return ret;