The "index" variable is used as an index into the usbphyc->phys[] array
which has usbphyc->nphys elements.  So if it is equal to usbphyc->nphys
then it is one element out of bounds.  The "index" comes from the
device tree so it's data that we trust and it's unlikely to be wrong,
however it's obviously still worth fixing the bug.  Change the > to >=.

Fixes: 94c358da3a05 ("phy: stm32: add support for STM32 USB PHY Controller (USBPHYC)")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/phy/st/phy-stm32-usbphyc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/phy/st/phy-stm32-usbphyc.c b/drivers/phy/st/phy-stm32-usbphyc.c
index 27fe92f73f33..b44afbff8616 100644
--- a/drivers/phy/st/phy-stm32-usbphyc.c
+++ b/drivers/phy/st/phy-stm32-usbphyc.c
@@ -712,7 +712,7 @@ static int stm32_usbphyc_probe(struct platform_device *pdev)
 		}
 
 		ret = of_property_read_u32(child, "reg", &index);
-		if (ret || index > usbphyc->nphys) {
+		if (ret || index >= usbphyc->nphys) {
 			dev_err(&phy->dev, "invalid reg property: %d\n", ret);
 			if (!ret)
 				ret = -EINVAL;
-- 
2.51.0

On Tue, 09 Dec 2025 09:53:36 +0300, Dan Carpenter wrote:
> The "index" variable is used as an index into the usbphyc->phys[] array
> which has usbphyc->nphys elements.  So if it is equal to usbphyc->nphys
> then it is one element out of bounds.  The "index" comes from the
> device tree so it's data that we trust and it's unlikely to be wrong,
> however it's obviously still worth fixing the bug.  Change the > to >=.
> 
> 
> [...]

Applied, thanks!

[1/1] phy: stm32-usphyc: Fix off by one in probe()
      commit: cabd25b57216ddc132efbcc31f972baa03aad15a

Best regards,
-- 
~Vinod

On 12/9/25 07:53, Dan Carpenter wrote:
> The "index" variable is used as an index into the usbphyc->phys[] array
> which has usbphyc->nphys elements.  So if it is equal to usbphyc->nphys
> then it is one element out of bounds.  The "index" comes from the
> device tree so it's data that we trust and it's unlikely to be wrong,
> however it's obviously still worth fixing the bug.  Change the > to >=.
> 
> Fixes: 94c358da3a05 ("phy: stm32: add support for STM32 USB PHY Controller (USBPHYC)")
> Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>

Hi Dan, thanks for your patch.

Reviewed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>

> ---
>   drivers/phy/st/phy-stm32-usbphyc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/phy/st/phy-stm32-usbphyc.c b/drivers/phy/st/phy-stm32-usbphyc.c
> index 27fe92f73f33..b44afbff8616 100644
> --- a/drivers/phy/st/phy-stm32-usbphyc.c
> +++ b/drivers/phy/st/phy-stm32-usbphyc.c
> @@ -712,7 +712,7 @@ static int stm32_usbphyc_probe(struct platform_device *pdev)
>   		}
>   
>   		ret = of_property_read_u32(child, "reg", &index);
> -		if (ret || index > usbphyc->nphys) {
> +		if (ret || index >= usbphyc->nphys) {
>   			dev_err(&phy->dev, "invalid reg property: %d\n", ret);
>   			if (!ret)
>   				ret = -EINVAL;