There's three ways to access PCI BARs from userspace: /dev/mem, sysfs files, and the old proc interface. Two check against iomem_is_exclusive, proc never did. And with CONFIG_IO_STRICT_DEVMEM, this starts to matter, since we don't want random userspace having access to PCI BARs while a driver is loaded and using it.
Fix this by adding the same iomem_is_exclusive() check we already have on the sysfs side in pci_mmap_resource(). Acked-by: Bjorn Helgaas <[email protected]> References: 90a545e98126 ("restrict /dev/mem to idle io memory ranges") Signed-off-by: Daniel Vetter <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Kees Cook <[email protected]> Cc: Dan Williams <[email protected]> Cc: Andrew Morton <[email protected]> Cc: John Hubbard <[email protected]> Cc: Jérôme Glisse <[email protected]> Cc: Jan Kara <[email protected]> Cc: Dan Williams <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: Bjorn Helgaas <[email protected]> Cc: [email protected] Signed-off-by: Daniel Vetter <[email protected]> -- v2: Improve commit message (Bjorn) --- drivers/pci/proc.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c index d35186b01d98..3a2f90beb4cb 100644 --- a/drivers/pci/proc.c +++ b/drivers/pci/proc.c @@ -274,6 +274,11 @@ static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma) else return -EINVAL; } + + if (dev->resource[i].flags & IORESOURCE_MEM && + iomem_is_exclusive(dev->resource[i].start)) + return -EINVAL; + ret = pci_mmap_page_range(dev, i, vma, fpriv->mmap_state, write_combine); if (ret < 0) -- 2.29.2
