Re: [PATCH v3] phy: exynos5-usbdrd: Use dynamic phy_cfg size to prevent OOB access

[Manivannan Sadhasivam]

On 2026-10-20 12:05 +0530, Selvarasu Ganesan wrote:
> The probe loop currently iterates using EXYNOS5_DRDPHYS_NUM (2),
> creating both UTMI and PIPE3 PHY instances regardless of the SoC
> capability. Several SoCs (Exynos2200, Exynos7870, Exynos850, Exynos990,
> and ExynosAutoV920) provide phy_cfg arrays containing only a single
> element.
> 
> On these SoCs, when the loop reaches index 1, the driver reads past the
> end of the rodata array, populating the second PHY instance with garbage
> data. Since the configuration structure contains critical function
> pointers (phy_isol, phy_init, set_refclk), any subsequent access to this
> PHY instance via exynos5_usbdrd_phy_xlate could result in a kernel oops.
> 
> Fix this by adding 'n_phy_cfg' to struct exynos5_usbdrd_phy_drvdata to
> store the actual size of the phy_cfg array for each SoC. Update the
> probe loop and the xlate function to bound their access against this
> value instead of the hardcoded EXYNOS5_DRDPHYS_NUM.
> 
> Fixes: 59025887fb08 ("phy: Add new Exynos5 USB 3.0 PHY driver")
> Cc: stable@xxxxxxxxxxxxxxx
> Assisted-by: LLM
> Signed-off-by: Selvarasu Ganesan <selvarasu.g@xxxxxxxxxxx>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>

- Mani