staging: xgifb: prevent video RAM size exceeding PCI window size

Add a sanity check for the video RAM size. It should fit into the
PCI window.

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/xgifb/XGI_main_26.c b/drivers/staging/xgifb/XGI_main_26.c
index ba6c347..98b8b09 100644 (file)
--- a/drivers/staging/xgifb/XGI_main_26.c
+++ b/drivers/staging/xgifb/XGI_main_26.c
@@ -1700,6 +1700,7 @@ static int __devinit xgifb_probe(struct pci_dev *pdev,
        struct fb_info *fb_info;
        struct xgifb_video_info *xgifb_info;
        struct xgi_hw_device_info *hw_info;
+       unsigned long video_size_max;
 
        fb_info = framebuffer_alloc(sizeof(*xgifb_info), &pdev->dev);
        if (!fb_info)
@@ -1720,6 +1721,7 @@ static int __devinit xgifb_probe(struct pci_dev *pdev,
        xgifb_info->subsysvendor = pdev->subsystem_vendor;
        xgifb_info->subsysdevice = pdev->subsystem_device;
 
+       video_size_max = pci_resource_len(pdev, 0);
        xgifb_info->video_base = pci_resource_start(pdev, 0);
        xgifb_info->mmio_base = pci_resource_start(pdev, 1);
        xgifb_info->mmio_size = pci_resource_len(pdev, 1);
@@ -1780,6 +1782,8 @@ static int __devinit xgifb_probe(struct pci_dev *pdev,
                        "Fatal error: Unable to determine RAM size.\n");
                ret = -ENODEV;
                goto error_disable;
+       } else if (xgifb_info->video_size > video_size_max) {
+               xgifb_info->video_size = video_size_max;
        }
 
        /* Enable PCI_LINEAR_ADDRESSING and MMIO_ENABLE  */