[v2] PCI: kirin: Fix buffer overflow

[PATCH v2] PCI: kirin: Fix buffer overflow

Posted by Alexandra Diupina 1 year, 4 months ago

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>
---
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) {
-- 
2.30.2

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

Posted by Mauro Carvalho Chehab 1 year, 3 months ago

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

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

Posted by Alexandra Diupina 1 year, 3 months ago

just a friendly reminder


19/07/24 15:21, Alexandra Diupina пишет:
> 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>
> ---
> 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) {

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

Posted by Krzysztof Wilczyński 1 year, 3 months ago

Hello,

> just a friendly reminder

Would you mind sending a v2 as a standalone patch?  So that I can pick it
up via Patchwork and such.  I would be much obliged.

I wonder if Mauro would be willing to have another review of the new
iteration of the fix.  Just something that would be nice to have his
tag added.

	Krzysztof