Don't allow null-terminated UCS-2/4 strings using the original API. #570
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Detect if the encoding is UCS-2/4 and the length is -1 in affected API functions and refuse to convert the string. If the string ends up being converted somehow, abort with an error message in DecodeDirect and ConvDirect. To convert a null terminated string in Decode/ConvDirect, a negative number corresponding to the width of the underlying character type for the encoding is expected; for example, if the encoding is "ucs-2" then a the size is expected to be -2. Also fix a 1-3 byte over-read in DecodeDirect when reading UCS-2/4 strings when a size is provided (found by OSS-Fuzz). Also fix a bug in DecodeDirect that caused DocumentChecker to return the wrong offsets when working with UCS-2/4 strings.
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More details available at: more details available at http://aspell.net/buffer-overread-ucs.txt |
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Detect if the encoding is UCS-2/4 and the length is -1 in affected API functions and refuse to convert the string. If the string ends up being converted somehow, abort with an error message in DecodeDirect and ConvDirect. To convert a null terminated string in Decode/ConvDirect, a negative number corresponding to the width of the underlying character type for the encoding is expected; for example, if the encoding is "ucs-2" then a the size is expected to be -2.
Also fix a 1-3 byte over-read in DecodeDirect when reading UCS-2/4 strings when a size is provided (found by OSS-Fuzz).
Also fix a bug in DecodeDirect that caused DocumentChecker to return the wrong offsets when working with UCS-2/4 strings.