commands: CmdPowerOn: Fix nlength return value in overflow case #130
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CmdPowerOn is supposed to return ATR and its length in buffer/nlength.
A bounds check is performed in the code, and truncates atr_len to the length of the received data (minus 10 bytes for the header). However, in that case, nlength in not updated, leading to a returned ATR with trailing garbage.
This is an edge, error case, that should never happen, and was introduced while fixing a potentially more serious buffer overrun in 2020.
Fixes: a382095 ("CmdPowerOn: fix a potention overrun with bogus ATR")