Re: [PATCH net 1/2] net: dsa: realtek: fix out-of-bounds access

[Linus Walleij]

On Wed, Mar 15, 2023 at 2:09 PM Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> wrote:

> The probe function sets priv->chip_data to (void *)priv + sizeof(*priv)
> with the expectation that priv has enough trailing space.
>
> However, only realtek-smi actually allocated this chip_data space.
> Do likewise in realtek-mdio to fix out-of-bounds accesses.
>
> Fixes: aac94001067d ("net: dsa: realtek: add new mdio interface for drivers")
> Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>

Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

That this worked for so long is kind of scary, and the reason why we run Kasan
over so much code, I don't know if Kasan would have found this one.

Rewriting the whole world in Rust will fix this problem, but it will
take a while...

Yours,
Linus Walleij