[PATCH] IOMUX: Fix access past end of console_devices

[Andy Shevchenko]

On Wed, Mar 30, 2022 at 7:49 PM Sean Anderson <seanga2 at gmail.com> wrote:
>
> We should only access console_devices[file][i] once we have checked that
> i < cd_count[file]. Otherwise, we will access uninitialized memory at the end of
> the loop. console_devices[file][i] should not be NULL, but putting the
> assignment in the loop condition allows us to ensure that i is checked
> beforehand. This isn't a bug, but it does make valgrind stop complaining.

> Fixes: 400797cad3 ("IOMUX: Split out for_each_console_dev() helper macro")

Has this been tested? See below.

...

>  #define for_each_console_dev(i, file, dev)             \
> -       for (i = 0, dev = console_devices[file][i];     \

When we enter the loop, the dev is assigned and perhaps valid

> -            i < cd_count[file];                        \
> -            i++, dev = console_devices[file][i])
> +       for (i = 0; i < cd_count[file] &&               \

Not the case anymore.

> +               (dev = console_devices[file][i]); i++)



-- 
With Best Regards,
Andy Shevchenko