Re: [PATCH v2 0/2] ACPI: battery: Fix various string handling issues

[Rafael J. Wysocki]

On Mon, Jan 30, 2023 at 10:14 AM Armin Wolf <W_Armin@xxxxxx> wrote:
>
> Am 19.01.23 um 15:21 schrieb Armin Wolf:
>
> > On my Dell Inspiron 3505, the battery model name was displayed
> > differently than when running Windows. While i first suspected an
> > ACPI issue, it turned out that the real reason was the ACPI battery
> > driver failing to handle strings larger than 32 bytes.
> >
> > This caused the model name of the battery (35 bytes long, hex string)
> > to miss proper NUL-termination, resulting in a buffer overread later.
> > Luckily, a valid string was stored right after the now invalid string,
> > appending only the battery serial number to the original model name.
> >
> > The first patch fixes a potential buffer overread then handling buffers,
> > while the second patch finally increases the maximum string length to
> > avoid truncating such larger strings.
> >
> > The patch series was tested on a Dell Inspiron 3505 and appears
> > to work properly.
>
> Are there any outstanding issues with the patch series which need
> to be fixed for mainline inclusion?

I'll have a look shortly and let you know.

Thanks!

> > ---
> > Changes in v2:
> > - Drop first patch since it was already applied
> > - combine the second and third patch
> > - do not replace 0 with '\0'
> > - spell ACPI in capitals
> > - rework the buffer length hdanling
> >
> > Armin Wolf (2):
> >    ACPI: battery: Fix buffer overread if not NUL-terminated
> >    ACPI: battery: Increase maximum string length
> >
> >   drivers/acpi/battery.c | 35 +++++++++++++++++++++++------------
> >   1 file changed, 23 insertions(+), 12 deletions(-)
> >
> > --