3 files changed, 15 insertions, 2 deletions

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index c88485860a0a..388440e0d222 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -569,7 +569,7 @@ void pci_remove_legacy_files(struct pci_bus *b)
 
 #ifdef HAVE_PCI_MMAP
 
-static int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma)
+int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma)
 {
         unsigned long nr, start, size;
 
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 9de87e9f98f5..d3e65e29df51 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -10,6 +10,10 @@ extern int pci_uevent(struct device *dev, struct kobj_uevent_env *env);
 extern int pci_create_sysfs_dev_files(struct pci_dev *pdev);
 extern void pci_remove_sysfs_dev_files(struct pci_dev *pdev);
 extern void pci_cleanup_rom(struct pci_dev *dev);
+#ifdef HAVE_PCI_MMAP
+extern int pci_mmap_fits(struct pci_dev *pdev, int resno,
+                         struct vm_area_struct *vma);
+#endif
 
 /**
  * Firmware PM callbacks
diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
index e1098c302c45..7fb086d39617 100644
--- a/drivers/pci/proc.c
+++ b/drivers/pci/proc.c
@@ -252,11 +252,20 @@ static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
         const struct proc_dir_entry *dp = PDE(inode);
         struct pci_dev *dev = dp->data;
         struct pci_filp_private *fpriv = file->private_data;
-        int ret;
+        int i, ret;
 
         if (!capable(CAP_SYS_RAWIO))
                 return -EPERM;
 
+        /* Make sure the caller is mapping a real resource for this device */
+        for (i = 0; i < PCI_ROM_RESOURCE; i++) {
+                if (pci_mmap_fits(dev, i, vma))
+                        break;
+        }
+
+        if (i >= PCI_ROM_RESOURCE)
+                return -ENODEV;
+
         ret = pci_mmap_page_range(dev, vma,
                                   fpriv->mmap_state,
                                   fpriv->write_combine);