Guard getNode() NULL result in set() and operator[] - #69
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… crash) getNode() reads AND writes a shared node cache (lastNodeGot / lastIndexGot / isCached) on every access. If two contexts (e.g. an ISR/RX-task producer and a main-loop consumer, as in ESP32Marauder's device lists) call into the list concurrently, that cache can be corrupted so getNode() walks off the end and returns NULL for an in-range index. set() and operator[] then dereferenced that NULL unconditionally (getNode(index)->data), crashing with a NULL write/read. get() already null-checks (returns T()), so only these two paths crash. Add the same guard: set() returns false, operator[] returns a static default-constructed fallback. No behavior change on the normal (non-corrupted) path.
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getNode()reads and writes a shared node cache (lastNodeGot/lastIndexGot/isCached) on every access, so concurrent access from two contexts can corrupt it and make it returnNULLfor an in-range index.set()andoperator[]then dereferenced that NULL unconditionally (getNode(index)->data) and crashed.get()already null-checks; this adds the same guard to the other two paths (set()returns false,operator[]returns a static default fallback). No change on the normal path.Found while auditing ESP32Marauder (which vendors this lib and calls it 'thread safe') for cross-task races.