diff options
Diffstat (limited to 'drivers/vfio/pci/vfio_pci_config.c')
| -rw-r--r-- | drivers/vfio/pci/vfio_pci_config.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c index 97422aafaa7b..ea2745c1ac5e 100644 --- a/drivers/vfio/pci/vfio_pci_config.c +++ b/drivers/vfio/pci/vfio_pci_config.c @@ -313,6 +313,10 @@ static int vfio_virt_config_read(struct vfio_pci_core_device *vdev, int pos, return count; } +static struct perm_bits direct_ro_perms = { + .readfn = vfio_direct_config_read, +}; + /* Default capability regions to read-only, no-virtualization */ static struct perm_bits cap_perms[PCI_CAP_ID_MAX + 1] = { [0 ... PCI_CAP_ID_MAX] = { .readfn = vfio_direct_config_read } @@ -1897,9 +1901,17 @@ static ssize_t vfio_config_do_rw(struct vfio_pci_core_device *vdev, char __user cap_start = *ppos; } else { if (*ppos >= PCI_CFG_SPACE_SIZE) { - WARN_ON(cap_id > PCI_EXT_CAP_ID_MAX); + /* + * We can get a cap_id that exceeds PCI_EXT_CAP_ID_MAX + * if we're hiding an unknown capability at the start + * of the extended capability list. Use default, ro + * access, which will virtualize the id and next values. + */ + if (cap_id > PCI_EXT_CAP_ID_MAX) + perm = &direct_ro_perms; + else + perm = &ecap_perms[cap_id]; - perm = &ecap_perms[cap_id]; cap_start = vfio_find_cap_start(vdev, *ppos); } else { WARN_ON(cap_id > PCI_CAP_ID_MAX); |