[PATCH 1/1] console: file should always be non-negative

[Simon Glass]

Hi Heinrich,

On Sat, 22 Oct 2022 at 03:49, Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
>
> We use the parameter file in console function to choose from an array after
> checking against MAX_FILES but we never check if the value of file is
> negative.
>
> Running ./u-boot -T -l and issuing the poweroff command has resulted in
> crashes because
>
> os_exit() results in std::ostream::flush() calling U-Boot's fflush with
> file being a pointer which when converted to int may be represented by a
> negative number.
>
> This shows that checking against MAX_FILES is not enough we have to ensure
> that the file argument is always positive.
>
> Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt at canonical.com>
> ---
>  common/console.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)

How about changing the 'file' parameter to a uint? It seems that this
is what it is supposed to be, from your checks.

Regards,
Simon