It is possible to safely use the same handler for multiple signals, but doing so increases the likelihood of a security vulnerability. The delivered signal is masked and is not delivered until the registered signal handler exits. However, if this same handler is registered to handle a different signal, execution of the handler may be interrupted by this new signal. If a signal handler is constructed with the expectation that it cannot be interrupted, a vulnerability might exist. To eliminate this attack vector, each signal handler should be registered to handle only one type of signal.
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