No direct issues come from using the same handler for multiple signals, but it broadens your susceptibility to other vulnerabilities. For instance, if a signal handler is constructed with the expectation that it will only be executed once, but it is registered to catch multiple signals, then that the handler may perform an operation multiple times that should only be performed once. Depending on what the handler does, this may provide a means to exploit other vulnerabilities. To eliminate this attack vector, each signal handler should only be registered to handle one type of signal.
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