On Mon, Jun 21, 2021 at 4:24 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> Commit 0ddcf3a6b442 ("platform/x86: think-lmi: Avoid potential read before
> start of the buffer") moved the lengt == 0 up to before stripping the '\n'
length
> which typically gets added when users echo a value to a sysfs-attribute
> from the shell.
>
> This avoids a potential buffer-underrun, but it also causes a behavioral
> change, prior to this change "echo > kbdlang", iow writing just a single
> '\n' would result in an EINVAL error, but after the change this gets
> accepted setting kbdlang to an empty string.
And why is it a problem?
I mean since we haven't yet released this in any of the kernels, the
ABIU can be adjusted one way or another.
> Re-add the length != 0 check after stripping the '\n' to reject this
> again, as before the change.
--
With Best Regards,
Andy Shevchenko
