Re: [patch] vfio: make an array larger

[walter harms <wharms@bfs.de>]

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



>