vfio/pci: make an array larger

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

The problem is that pci_cap_length[] was defined as large enough to
hold "PCI_CAP_ID_AF + 1" elements.  The code in vfio_cap_init() assumes
it has PCI_CAP_ID_MAX + 1 elements.  Originally, PCI_CAP_ID_AF and
PCI_CAP_ID_MAX were the same but then we introduced PCI_CAP_ID_EA in
commit f80b0ba95964 ("PCI: Add Enhanced Allocation register entries")
so now the array is too small.

Let's fix this by making the array size PCI_CAP_ID_MAX + 1.  And let's
make a similar change to pci_ext_cap_length[] for consistency.  Also
both these arrays can be made const.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
index a8657ef6382fb49dba38d3523a14d99e140519ae..fe2b470d7ec6b33c8fd75ffbfccb1168a6975ca2 100644 (file)
--- 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 const 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,
@@ -74,7 +74,7 @@ static u8 pci_cap_length[] = {
  *   0: Removed or masked from the user visible capabilty list
  *   FF: Variable length
  */
-static u16 pci_ext_cap_length[] = {
+static const u16 pci_ext_cap_length[PCI_EXT_CAP_ID_MAX + 1] = {
        [PCI_EXT_CAP_ID_ERR]    =       PCI_ERR_ROOT_COMMAND,
        [PCI_EXT_CAP_ID_VC]     =       0xFF,
        [PCI_EXT_CAP_ID_DSN]    =       PCI_EXT_CAP_DSN_SIZEOF,