ANDROID: binder: fix proc->tsk check.

Commit c4ea41b ("binder: use group leader instead of open thread")'
was incomplete and didn't update a check in binder_mmap(), causing all
mmap() calls into the binder driver to fail.

Signed-off-by: Martijn Coenen <[email protected]>
Tested-by: John Stultz <[email protected]>
Cc: stable <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: Martijn Coenen

drivers/android/binder.c

@@ -3362,7 +3362,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma)
 	const char *failure_string;
 	struct binder_buffer *buffer;
 
-	if (proc->tsk != current)
+	if (proc->tsk != current->group_leader)
 		return -EINVAL;
 
 	if ((vma->vm_end - vma->vm_start) > SZ_4M)