Re: [PATCH] phy: fix compiler array bounds warning on settings[]

[Florian Fainelli]

2014-03-04 16:35 GMT-08:00 Bjorn Helgaas <bhelgaas@xxxxxxxxxx>:
> With -Werror=array-bounds, gcc v4.7.x warns that in phy_find_valid(), the
> settings[] "array subscript is above array bounds", I think because idx is
> a signed integer and if the caller supplied idx < 0, we pass the guard but
> still reference out of bounds.
>
> Fix this by making idx unsigned here and elsewhere.
>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>

Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx>

> ---
>  drivers/net/phy/phy.c |   11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
> index 19c9eca0ef26..76d96b9ebcdb 100644
> --- a/drivers/net/phy/phy.c
> +++ b/drivers/net/phy/phy.c
> @@ -164,9 +164,9 @@ static const struct phy_setting settings[] = {
>   *   of that setting.  Returns the index of the last setting if
>   *   none of the others match.
>   */
> -static inline int phy_find_setting(int speed, int duplex)
> +static inline unsigned int phy_find_setting(int speed, int duplex)
>  {
> -       int idx = 0;
> +       unsigned int idx = 0;
>
>         while (idx < ARRAY_SIZE(settings) &&
>                (settings[idx].speed != speed || settings[idx].duplex != duplex))
> @@ -185,7 +185,7 @@ static inline int phy_find_setting(int speed, int duplex)
>   *   the mask in features.  Returns the index of the last setting
>   *   if nothing else matches.
>   */
> -static inline int phy_find_valid(int idx, u32 features)
> +static inline unsigned int phy_find_valid(unsigned int idx, u32 features)
>  {
>         while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
>                 idx++;
> @@ -204,7 +204,7 @@ static inline int phy_find_valid(int idx, u32 features)
>  static void phy_sanitize_settings(struct phy_device *phydev)
>  {
>         u32 features = phydev->supported;
> -       int idx;
> +       unsigned int idx;
>
>         /* Sanitize settings based on PHY capabilities */
>         if ((features & SUPPORTED_Autoneg) == 0)
> @@ -954,7 +954,8 @@ int phy_init_eee(struct phy_device *phydev, bool clk_stop_enable)
>             (phydev->interface == PHY_INTERFACE_MODE_RGMII))) {
>                 int eee_lp, eee_cap, eee_adv;
>                 u32 lp, cap, adv;
> -               int idx, status;
> +               int status;
> +               unsigned int idx;
>
>                 /* Read phy status to properly get the right settings */
>                 status = phy_read_status(phydev);
>
> --
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Florian
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/