From: Changbin Du <changbin.du@xxxxxxxxx>
If we detected a invalid PCI ROM (e.g. Invalid PCI ROM header signature),
we should unmap it immediately and fail. It doesn't make any sense that
return a mapped area with size of 0.
I have seen this case on Intel GVTg vGPU, which have 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@xxxxxxxxx>
---
drivers/pci/rom.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c
index b6edb18..1f5e6af 100644
--- a/drivers/pci/rom.c
+++ b/drivers/pci/rom.c
@@ -147,12 +147,8 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size)
return NULL;
rom = ioremap(start, *size);
- if (!rom) {
- /* restore enable if ioremap fails */
- if (!(res->flags & IORESOURCE_ROM_ENABLE))
- pci_disable_rom(pdev);
- return NULL;
- }
+ if (!rom)
+ goto err_ioremap;
/*
* Try to find the true size of the ROM since sometimes the PCI window
@@ -160,7 +156,18 @@ 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))
+ pci_disable_rom(pdev);
+ return NULL;
}
EXPORT_SYMBOL(pci_map_rom);
--
2.7.4
