Re: [PATCH RFC] brcmfmac: sanitize DMI strings v2

From: Kalle Valo
Date: Mon May 06 2019 - 08:27:16 EST

Hans de Goede <hdegoede@xxxxxxxxxx> writes:

> If we're going to do some filtering, then I suggest we play it safe and also
> disallow other chars which may be used as a separator somewhere, specifically
> ':' and ','.
> Currently upstream linux-firmware has these files which rely on the DMI
> matching:
> brcmfmac4330-sdio.Prowise-PT301.txt
> brcmfmac43430-sdio.Hampoo-D2D3_Vi8A1.txt
> brcmfmac43430a0-sdio.ONDA-V80 PLUS.txt
> The others are either part of the DMI override table for devices with unsuitable
> DMI strings like "Default String"; or are device-tree based.
> So as long as we don't break those 3 (or break the ONDA one but get a symlink
> in place) we can sanitize a bit more then just non-printable and '/'.
> Kalle, Arend, what is your opinion on this?
> Note I do not expect the ONDA V80 Plus to have a lot of Linux users,
> but it definitely has some.

To me having spaces in filenames is a bad idea, but on the other hand we
do have the "don't break existing setups" rule, so it's not so simple. I
vote for not allowing spaces, I think that's the best for the long run,
but don't know what Arend thinks.

Maybe we could do some kind of fallback mechanism, like first trying the
sanitised filename and if that's not found then we try the old filename
with spaces? And if that old filename works we print a big fat warning
that the user should update the file and that the old "filename with
spaces" support is going away soon?

Kalle Valo