Hi,

On 9/28/21 12:11 PM, Arnd Bergmann wrote:

On Tue, Sep 28, 2021 at 11:40 AM Hans de Goede [off-list ref] wrote:

quoted

On 9/27/21 8:33 PM, Linus Torvalds wrote:

quoted

On Mon, Sep 27, 2021 at 6:22 AM Arnd Bergmann [off-list ref] wrote:

quoted

More specifically, ' think '\377' may be either -1 or 255 depending on
the architecture.
On most architectures, 'char' is implicitly signed, but on some others
it is not.

Yeah. That code is just broken.

And Arnd, your patch may be "conceptually minimal", in that it keeps
thed broken code and makes it work. But it just dials up the oddity to
11.

Thank you for addressing it. I usually try to avoid overthinking changes
to "unusual" code like this, but your solution is clearly an improvement.

What really threw me off this time is that my first attempt to address
the warning was an exact revert of 9d682ea6bcc7 ("vboxsf: Fix the
check for the old binary mount-arguments struct"), which in turn
came from a tool that is usually correct and and that both Dan
and Al thought the original patch was correct when it looked like
it turned a working (though unusual) implementation  into a broken
one.

quoted

I agree that your suggestion is to be the best solution,
so how do we move forward with this, do I turn this into a
proper patch with you as the author and Arnd as Reported-by and
if yes may I add your Signed-off-by to the patch ?

It's already upstream, see d5f6545934c4 ("qnx4: work around gcc
false positive warning bug").

Ah, actually you mean: 9b3b353ef330 ("vboxfs: fix broken legacy mount
signature checking"), but other then that yes you're right it
is already upstream.

Thank you Arnd and thank you Linus.

Regards,

Hans