fix: cap advertised max buffer size at 2^24 - 1 - #45
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The 16 MiB constant (16 << 20) is exactly 2^24, but the serprog length field is 24-bit little-endian, so it wrapped to zero: QWrNMaxLen and QRdNMaxLen replied with a maximum length of 0. Use 2^24 - 1 so the advertised maximum is representable.
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The 16 MiB constant (16 << 20) is exactly 2^24, but the serprog length field is 24-bit little-endian, so it wrapped to zero: QWrNMaxLen and QRdNMaxLen replied with a maximum length of 0. Use 2^24 - 1 so the advertised maximum is representable.
FWIW, flashrom works around this bug: https://github.com/flashrom/flashrom/blob/main/programmers/serprog.c#L784-L785