Re: [PATCH net] net: phy: dp83869: fix memory corruption when enabling fiber

From: Sverdlin, Alexander
Date: Wed Oct 02 2024 - 12:47:47 EST


On Wed, 2024-10-02 at 18:18 +0200, Ingo van Lil wrote:
> When configuring the fiber port, the DP83869 PHY driver incorrectly
> calls linkmode_set_bit() with a bit mask (1 << 10) rather than a bit
> number (10). This corrupts some other memory location -- in case of
> arm64 the priv pointer in the same structure.
>
> Since the advertising flags are updated from supported at the end of the
> function the incorrect line isn't needed at all and can be removed.
>
> Fixes: a29de52ba2a1 ("net: dp83869: Add ability to advertise Fiber connection")
> Signed-off-by: Ingo van Lil <inguin@xxxxxx>

You've probably forgot "v2" in the [PATCH], nevertheless,

Reviewed-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxxxx>

> ---
>  drivers/net/phy/dp83869.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/drivers/net/phy/dp83869.c b/drivers/net/phy/dp83869.c
> index d7aaefb5226b..5f056d7db83e 100644
> --- a/drivers/net/phy/dp83869.c
> +++ b/drivers/net/phy/dp83869.c
> @@ -645,7 +645,6 @@ static int dp83869_configure_fiber(struct phy_device *phydev,
>        phydev->supported);
>
>   linkmode_set_bit(ETHTOOL_LINK_MODE_FIBRE_BIT, phydev->supported);
> - linkmode_set_bit(ADVERTISED_FIBRE, phydev->advertising);
>
>   if (dp83869->mode == DP83869_RGMII_1000_BASE) {
>   linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,

--
Alexander Sverdlin
Siemens AG
www.siemens.com