Re: [patch] vfio: make an array larger

walter harms
2015-11-04T21:49:14Z

Am 04.11.2015 14:26, schrieb Dan Carpenter:
> Smatch complains about a possible out of bounds error:
>
> drivers/vfio/pci/vfio_pci_config.c:1241 vfio_cap_init()
> error: buffer overflow 'pci_cap_length' 20 <= 20
>
> Fix this by making the array larger.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>
> diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
> index ff75ca3..001d48a 100644
> --- a/drivers/vfio/pci/vfio_pci_config.c
> +++ b/drivers/vfio/pci/vfio_pci_config.c
> @@ -46,7 +46,7 @@
> * 0: Removed from the user visible capability list
> * FF: Variable length
> */
> -static u8 pci_cap_length[] = {
> +static u8 pci_cap_length[PCI_CAP_ID_MAX + 1] = {
> [PCI_CAP_ID_BASIC] = PCI_STD_HEADER_SIZEOF, /* pci config header */
> [PCI_CAP_ID_PM] = PCI_PM_SIZEOF,
> [PCI_CAP_ID_AGP] = PCI_AGP_SIZEOF,

(i am sorry Dave)

I am not sure if that is the way to go.
this define make me feel uneasy,
#define PCI_CAP_ID_MAX PCI_CAP_ID_AF

Would it be possible to ARRAY_SIZE(pci_cap_length) instead of PCI_CAP_ID_MAX ?
Then that would grow automatically with the array. And its more clear what
is actually happening.

re,
wh

>