RE: [PATCH] PCI: endpoint: Fix NULL pointer dereference for ->get_features()

[Sriram Dash]

> From: Shradha Todi <shradha.t@xxxxxxxxxxx>
> Subject: [PATCH] PCI: endpoint: Fix NULL pointer dereference for -
> >get_features()
> 
> get_features ops of pci_epc_ops may return NULL, causing NULL pointer
> dereference in pci_epf_test_bind function. Let us add a check for
> pci_epc_feature pointer in pci_epf_test_bind before we access it to avoid any
> such NULL pointer dereference and return -ENOTSUPP in case pci_epc_feature
> is not found.
> 
> Reviewed-by: Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx>
> Signed-off-by: Sriram Dash <sriram.dash@xxxxxxxxxxx>
> Signed-off-by: Shradha Todi <shradha.t@xxxxxxxxxxx>
> ---

Hi Kishon,

Any update on this?


>  drivers/pci/endpoint/functions/pci-epf-test.c | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c
> b/drivers/pci/endpoint/functions/pci-epf-test.c
> index c9121b1b9fa9..af4537a487bf 100644
> --- a/drivers/pci/endpoint/functions/pci-epf-test.c
> +++ b/drivers/pci/endpoint/functions/pci-epf-test.c
> @@ -510,14 +510,17 @@ static int pci_epf_test_bind(struct pci_epf *epf)
>  		return -EINVAL;
> 
>  	epc_features = pci_epc_get_features(epc, epf->func_no);
> -	if (epc_features) {
> -		linkup_notifier = epc_features->linkup_notifier;
> -		msix_capable = epc_features->msix_capable;
> -		msi_capable = epc_features->msi_capable;
> -		test_reg_bar = pci_epc_get_first_free_bar(epc_features);
> -		pci_epf_configure_bar(epf, epc_features);
> +	if (!epc_features) {
> +		dev_err(dev, "epc_features not implemented\n");
> +		return -ENOTSUPP;
>  	}
> 
> +	linkup_notifier = epc_features->linkup_notifier;
> +	msix_capable = epc_features->msix_capable;
> +	msi_capable = epc_features->msi_capable;
> +	test_reg_bar = pci_epc_get_first_free_bar(epc_features);
> +	pci_epf_configure_bar(epf, epc_features);
> +
>  	epf_test->test_reg_bar = test_reg_bar;
>  	epf_test->epc_features = epc_features;
> 
> --
> 2.17.1