Fix: Cap DNS answer loop iterations to prevent DoS#1329
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felicityzhao9 wants to merge 2 commits intoFreeRTOS:mainfrom
Open
Fix: Cap DNS answer loop iterations to prevent DoS#1329felicityzhao9 wants to merge 2 commits intoFreeRTOS:mainfrom
felicityzhao9 wants to merge 2 commits intoFreeRTOS:mainfrom
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Description
In the current implementation, the loop iterates up to pxSet->usAnswers, which is derived directly from the packet header. The early-exit condition depends on usNumARecordsStored reaching ipconfigDNS_CACHE_ADDRESSES_PER_ENTRY, but this counter is only incremented when pxSet->xDoStore != pdFALSE. As a result, for unexpected replies, the counter never increases and the loop may continue iterating over all advertised answers and potentially perform excessive work.
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