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} +/* + * User space can randomly change their names anyway, so locking for readers + * doesn't make sense. For writers, locking is probably necessary, as a race + * condition could lead to long-term mixed results. + */ char *__get_task_comm(char *buf, size_t buf_size, struct task_struct *tsk) { - task_lock(tsk); /* Always NUL terminated and zero-padded */ strscpy_pad(buf, tsk->comm, buf_size); - task_unlock(tsk); return buf; } EXPORT_SYMBOL_GPL(__get_task_comm); diff --git a/include/linux/sched.h b/include/linux/sched.h index c75fd46506df..56a927393a38 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1083,7 +1083,7 @@ struct task_struct { * * - normally initialized setup_new_exec() * - access it with [gs]et_task_comm() - * - lock it with task_lock() + * - lock it with task_lock() for writing */ char comm[TASK_COMM_LEN];