[PATCH 03/11] PCI: pci_stub: Suppress kernel DMA ownership auto-claiming

From: Lu Baolu
Date: Sun Nov 14 2021 - 21:14:41 EST


pci_stub allows the admin to block driver binding on a device and make
it permanently shared with userspace. Since pci_stub does not do DMA,
it is safe. However the admin must understand that using pci_stub allows
userspace to attack whatever device it was bound to.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/pci/pci-stub.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/pci/pci-stub.c b/drivers/pci/pci-stub.c
index e408099fea52..6324c68602b4 100644
--- a/drivers/pci/pci-stub.c
+++ b/drivers/pci/pci-stub.c
@@ -36,6 +36,9 @@ static struct pci_driver stub_driver = {
.name = "pci-stub",
.id_table = NULL, /* only dynamic id's */
.probe = pci_stub_probe,
+ .driver = {
+ .suppress_auto_claim_dma_owner = true,
+ },
};

static int __init pci_stub_init(void)
--
2.25.1