[1.1.x] Bugfix for buffer-overflow in cardreader #10925
Merged
+3
−4
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Description
In
CardReader::diveToFile, the calculatedlen(length of the directory name) is not validated before being used tostrncpythe directory name to the array of fixed sizedosSubdirname[FILENAME_LENGTH].For overly long directory names, this results in a buffer-overflow which can be triggered by several SD card related G-Code instructions.
The same issue applies to the 2.0.x branch of Marlin.
Benefits
The error can be prevented by checking the resulting length of the directory name.