PCI: Fail pci_map_rom() if the option ROM is invalid

If we detect a invalid PCI option ROM (e.g., invalid ROM header signature),
we should unmap it immediately and fail. It doesn't make any sense to
return a mapped area with size of 0.

I have seen this case on Intel GVTg vGPU, which has no VBIOS. It will not
cause a real problem, but we should skip it as early as possible.

Signed-off-by: Changbin Du <changbin.du@intel.com>
[bhelgaas: split non-functional change into separate patch]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Changbin Du 2017-11-07 18:26:53 -06:00 committed by Bjorn Helgaas
parent a48a687d8c
commit a405f191f4

View File

@ -156,8 +156,13 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
* True size is important if the ROM is going to be copied.
*/
*size = pci_get_rom_size(pdev, rom, *size);
if (!*size)
goto invalid_rom;
return rom;
invalid_rom:
iounmap(rom);
err_ioremap:
/* restore enable if ioremap fails */
if (!(res->flags & IORESOURCE_ROM_ENABLE))