ASoC: tas2781: bound firmware description string parsing

In the Linux kernel, the following vulnerability has been resolved: ASoC: tas2781: bound firmware description string parsing The TAS2781 firmware parser reads several variable-length description strings with strlen() before checking that the string terminator is present inside the firmware blob. A malformed firmware image without a NUL terminator can therefore make the parser walk past the end of the firmware buffer before the later size checks run. Add a small bounded string-length helper and use it for all description fields that are parsed from the firmware buffer. Keep the existing size checks for the fixed bytes that follow each string.

Where it's fixed