Re: [PATCH v2] PCI: kirin: Fix buffer overflow

[Mauro Carvalho Chehab <mchehab+huawei@kernel.org>]

Em Fri, 19 Jul 2024 15:21:53 +0300
Alexandra Diupina <adiupina@astralinux.ru> escreveu:

> In kirin_pcie_parse_port() pcie->num_slots is compared to
> pcie->gpio_id_reset size (MAX_PCI_SLOTS). Need to fix
> condition to pcie->num_slots + 1 >= MAX_PCI_SLOTS and move
> pcie->num_slots increment lower to avoid out-of-bounds
> array access.
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
> 
> Fixes: b22dbbb24571 ("PCI: kirin: Support PERST# GPIOs for HiKey970 external PEX 8606 bridge")
> Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>

LGTM.

Reviewed-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

> ---
> v2: some changes
>  drivers/pci/controller/dwc/pcie-kirin.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-kirin.c b/drivers/pci/controller/dwc/pcie-kirin.c
> index d5523f302102..deab1e653b9a 100644
> --- a/drivers/pci/controller/dwc/pcie-kirin.c
> +++ b/drivers/pci/controller/dwc/pcie-kirin.c
> @@ -412,12 +412,12 @@ static int kirin_pcie_parse_port(struct kirin_pcie *pcie,
>  			if (pcie->gpio_id_reset[i] < 0)
>  				continue;
>  
> -			pcie->num_slots++;
> -			if (pcie->num_slots > MAX_PCI_SLOTS) {
> +			if (pcie->num_slots + 1 >= MAX_PCI_SLOTS) {
>  				dev_err(dev, "Too many PCI slots!\n");
>  				ret = -EINVAL;
>  				goto put_node;
>  			}
> +			pcie->num_slots++;
>  
>  			ret = of_pci_get_devfn(child);
>  			if (ret < 0) {



Thanks,
Mauro