github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-05-12 16:18:45 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity

PCI: use generic driver_override infrastructure

Browse Source 
When a driver is probed through __driver_attach(), the bus' match()
callback is called without the device lock held, thus accessing the
driver_override field without a lock, which can cause a UAF.

Fix this by using the driver-core driver_override infrastructure taking
care of proper locking internally.

Note that calling match() from __driver_attach() without the device lock
held is intentional. [1]

Link: https://lore.kernel.org/driver-core/DGRGTIRHA62X.3RY09D9SOK77P@kernel.org/ [1]
Reported-by: Gui-Dong Han <hanguidong02@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220789
Fixes: 782a985d7a ("PCI: Introduce new device binding path using pci_dev.driver_override")
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex@shazbot.org>
Tested-by: Gui-Dong Han <hanguidong02@gmail.com>
Reviewed-by: Gui-Dong Han <hanguidong02@gmail.com>
Link: https://patch.msgid.link/20260324005919.2408620-6-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
This commit is contained in:
Danilo Krummrich 2026-03-24 01:59:09 +01:00
parent 1cf996ac30
commit 10a4206a24
6 changed files with 13 additions and 44 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
drivers/pci/pci-driver.c
View File

@ -138,9 +138,11 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
{
struct pci_dynid *dynid;
const struct pci_device_id *found_id = NULL, *ids;
int ret;
/* When driver_override is set, only bind to the matching driver */
if (dev->driver_override && strcmp(dev->driver_override, drv->name))
ret = device_match_driver_override(&dev->dev, &drv->driver);
if (ret == 0)
return NULL;
/* Look at the dynamic ids first, before the static ones */
@ -164,7 +166,7 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
* matching.
*/
if (found_id->override_only) {
if (dev->driver_override)
if (ret > 0)
return found_id;
} else {
return found_id;
@ -172,7 +174,7 @@ static const struct pci_device_id *pci_match_device(struct pci_driver *drv,
}
/* driver_override will always match, send a dummy id */
if (dev->driver_override)
if (ret > 0)
return &pci_device_id_any;
return NULL;
}
@ -452,7 +454,7 @@ static int __pci_device_probe(struct pci_driver *drv, struct pci_dev *pci_dev)
static inline bool pci_device_can_probe(struct pci_dev *pdev)
{
return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||
pdev->driver_override);
device_has_driver_override(&pdev->dev));
}
#else
static inline bool pci_device_can_probe(struct pci_dev *pdev)
@ -1722,6 +1724,7 @@ static const struct cpumask *pci_device_irq_get_affinity(struct device *dev,
const struct bus_type pci_bus_type = {
.name = "pci",
.driver_override = true,
.match = pci_bus_match,
.uevent = pci_uevent,
.probe = pci_device_probe,

28
drivers/pci/pci-sysfs.c
View File

@ -615,33 +615,6 @@ static ssize_t devspec_show(struct device *dev,
static DEVICE_ATTR_RO(devspec);
#endif
static ssize_t driver_override_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct pci_dev *pdev = to_pci_dev(dev);
int ret;
ret = driver_set_override(dev, &pdev->driver_override, buf, count);
if (ret)
return ret;
return count;
}
static ssize_t driver_override_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct pci_dev *pdev = to_pci_dev(dev);
ssize_t len;
device_lock(dev);
len = sysfs_emit(buf, "%s\n", pdev->driver_override);
device_unlock(dev);
return len;
}
static DEVICE_ATTR_RW(driver_override);
static struct attribute *pci_dev_attrs[] = {
&dev_attr_power_state.attr,
&dev_attr_resource.attr,
@ -669,7 +642,6 @@ static struct attribute *pci_dev_attrs[] = {
#ifdef CONFIG_OF
&dev_attr_devspec.attr,
#endif
&dev_attr_driver_override.attr,
&dev_attr_ari_enabled.attr,
NULL,
};

1
drivers/pci/probe.c
View File

@ -2488,7 +2488,6 @@ static void pci_release_dev(struct device *dev)
pci_release_of_node(pci_dev);
pcibios_release_device(pci_dev);
pci_bus_put(pci_dev->bus);
kfree(pci_dev->driver_override);
bitmap_free(pci_dev->dma_alias_mask);
dev_dbg(dev, "device released\n");
kfree(pci_dev);

5
drivers/vfio/pci/vfio_pci_core.c
View File

@ -1987,9 +1987,8 @@ static int vfio_pci_bus_notifier(struct notifier_block *nb,
pdev->is_virtfn && physfn == vdev->pdev) {
pci_info(vdev->pdev, "Captured SR-IOV VF %s driver_override\n",
pci_name(pdev));
pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
vdev->vdev.ops->name);
WARN_ON(!pdev->driver_override);
WARN_ON(device_set_driver_override(&pdev->dev,
vdev->vdev.ops->name));
} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
pdev->is_virtfn && physfn == vdev->pdev) {
struct pci_driver *drv = pci_dev_driver(pdev);

6
drivers/xen/xen-pciback/pci_stub.c
View File

@ -598,6 +598,8 @@ static int pcistub_seize(struct pci_dev *dev,
return err;
}
static struct pci_driver xen_pcibk_pci_driver;
/* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
* other functions that take the sysfs lock. */
static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
@ -609,8 +611,8 @@ static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
match = pcistub_match(dev);
if ((dev->driver_override &&
!strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
if (device_match_driver_override(&dev->dev,
&xen_pcibk_pci_driver.driver) > 0 ||
match) {
if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL

6
include/linux/pci.h
View File

@ -575,12 +575,6 @@ struct pci_dev {
u8 supported_speeds; /* Supported Link Speeds Vector */
phys_addr_t rom; /* Physical address if not from BAR */
size_t romlen; /* Length if not from BAR */
/*
* Driver name to force a match. Do not set directly, because core
* frees it. Use driver_set_override() to set or clear it.
*/
const char *driver_override;
unsigned long priv_flags; /* Private flags for the PCI driver */
/* These methods index pci_reset_fn_methods[] */