Fix use-after-free and memory leak in mqtt_pit.c#20
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juandiego-bmu wants to merge 2 commits intohoneynet:mainfrom
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Fix use-after-free and memory leak in mqtt_pit.c#20juandiego-bmu wants to merge 2 commits intohoneynet:mainfrom
juandiego-bmu wants to merge 2 commits intohoneynet:mainfrom
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When disconnectClient() is called inside the packet processing switch, it frees the client struct. But break only exits the switch, not the for loop — so the code after the loop still accesses the freed client (reading bytesWrittenToBuffer, calling memmove on client->buffer). Added a clientDisconnected flag that breaks out of both the switch and the for loop, and guards the post-loop buffer cleanup so it only runs when the client is still alive. Also added free(arr) to sendPubrel() which was leaking a small allocation on every call. Fixes honeynet#19
lookupClient() can return NULL if the fd is not found in the hash table. The code on line 873 used the return value immediately without checking, which would cause a NULL pointer dereference. Now we safely remove the fd from epoll and close it if the client is not found.
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Fixes the use-after-free and the
sendPubrel()memory leak reported in #19.Use-after-free in packet processing loop
When
disconnectClient()is called inside the switch (DISCONNECT, CONNECT failure, PUBCOMP, PING), it frees the client struct. Butbreakonly exits the switch, not theforloop — so after the loop, lines like:are accessing freed memory. Also, if there are multiple MQTT packets in one TCP segment, the loop keeps iterating and reads
client->bufferagain.Fix: added a
clientDisconnectedflag that breaks out of both the switch and the for loop, and wraps the post-loop buffer cleanup inif (!clientDisconnected).Memory leak in
sendPubrel()sendPubrel()callsmallocbut neverfrees the buffer. Addedfree(arr)before both return paths, matching the pattern used bysendConnack.Fixes #19