staging: android: binder.c: Use more appropriate functions for euid retrieval

Instead of getting the reference to whole credential structure, use
task_euid() and current_euid() to get it.

Signed-off-by: Tair Rzayev <tair.rzayev@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/android/binder.c b/drivers/staging/android/binder.c
index e8dd7dd..989f809 100644 (file)
--- a/drivers/staging/android/binder.c
+++ b/drivers/staging/android/binder.c
@@ -1326,7 +1326,6 @@ static void binder_transaction(struct binder_proc *proc,
        struct binder_transaction *in_reply_to = NULL;
        struct binder_transaction_log_entry *e;
        uint32_t return_error;
-       const struct cred *cred = __task_cred(proc->tsk);
 
        e = binder_transaction_log_add(&binder_transaction_log);
        e->call_type = reply ? 2 : !!(tr->flags & TF_ONE_WAY);
@@ -1468,7 +1467,7 @@ static void binder_transaction(struct binder_proc *proc,
                t->from = thread;
        else
                t->from = NULL;
-       t->sender_euid = cred->euid;
+       t->sender_euid = task_euid(proc->tsk);
        t->to_proc = target_proc;
        t->to_thread = target_thread;
        t->code = tr->code;
@@ -2602,7 +2601,7 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
        struct binder_thread *thread;
        unsigned int size = _IOC_SIZE(cmd);
        void __user *ubuf = (void __user *)arg;
-       const struct cred *cred = current_cred();
+       kuid_t curr_euid = current_euid();
 
        /*pr_info("binder_ioctl: %d:%d %x %lx\n", proc->pid, current->pid, cmd, arg);*/
 
@@ -2688,15 +2687,16 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
                        goto err;
                }
                if (uid_valid(binder_context_mgr_uid)) {
-                       if (!uid_eq(binder_context_mgr_uid, cred->euid)) {
+                       if (!uid_eq(binder_context_mgr_uid, curr_euid)) {
                                pr_err("BINDER_SET_CONTEXT_MGR bad uid %d != %d\n",
-                                      from_kuid(&init_user_ns, cred->euid),
+                                      from_kuid(&init_user_ns, curr_euid),
                                       from_kuid(&init_user_ns, binder_context_mgr_uid));
                                ret = -EPERM;
                                goto err;
                        }
-               } else
-                       binder_context_mgr_uid = cred->euid;
+               } else {
+                       binder_context_mgr_uid = curr_euid;
+               }
                binder_context_mgr_node = binder_new_node(proc, 0, 0);
                if (binder_context_mgr_node == NULL) {
                        ret = -ENOMEM;