Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
PCI: use generic driver_override infrastructure
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: 782a985d7af2 ("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>
+13
-44
+7
-4
drivers/pci/pci-driver.c
+7
-4
drivers/pci/pci-driver.c
···
138
138
{
139
139
struct pci_dynid *dynid;
140
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const struct pci_device_id *found_id = NULL, *ids;
141
+
int ret;
141
142
142
143
/* When driver_override is set, only bind to the matching driver */
143
-
if (dev->driver_override && strcmp(dev->driver_override, drv->name))
144
+
ret = device_match_driver_override(&dev->dev, &drv->driver);
145
+
if (ret == 0)
144
146
return NULL;
145
147
146
148
/* Look at the dynamic ids first, before the static ones */
···
166
164
* matching.
167
165
*/
168
166
if (found_id->override_only) {
169
-
if (dev->driver_override)
167
+
if (ret > 0)
170
168
return found_id;
171
169
} else {
172
170
return found_id;
···
174
172
}
175
173
176
174
/* driver_override will always match, send a dummy id */
177
-
if (dev->driver_override)
175
+
if (ret > 0)
178
176
return &pci_device_id_any;
179
177
return NULL;
180
178
}
···
454
452
static inline bool pci_device_can_probe(struct pci_dev *pdev)
455
453
{
456
454
return (!pdev->is_virtfn || pdev->physfn->sriov->drivers_autoprobe ||
457
-
pdev->driver_override);
455
+
device_has_driver_override(&pdev->dev));
458
456
}
459
457
#else
460
458
static inline bool pci_device_can_probe(struct pci_dev *pdev)
···
1724
1722
1725
1723
const struct bus_type pci_bus_type = {
1726
1724
.name = "pci",
1725
+
.driver_override = true,
1727
1726
.match = pci_bus_match,
1728
1727
.uevent = pci_uevent,
1729
1728
.probe = pci_device_probe,
-28
drivers/pci/pci-sysfs.c
-28
drivers/pci/pci-sysfs.c
···
615
615
static DEVICE_ATTR_RO(devspec);
616
616
#endif
617
617
618
-
static ssize_t driver_override_store(struct device *dev,
619
-
struct device_attribute *attr,
620
-
const char *buf, size_t count)
621
-
{
622
-
struct pci_dev *pdev = to_pci_dev(dev);
623
-
int ret;
624
-
625
-
ret = driver_set_override(dev, &pdev->driver_override, buf, count);
626
-
if (ret)
627
-
return ret;
628
-
629
-
return count;
630
-
}
631
-
632
-
static ssize_t driver_override_show(struct device *dev,
633
-
struct device_attribute *attr, char *buf)
634
-
{
635
-
struct pci_dev *pdev = to_pci_dev(dev);
636
-
ssize_t len;
637
-
638
-
device_lock(dev);
639
-
len = sysfs_emit(buf, "%s\n", pdev->driver_override);
640
-
device_unlock(dev);
641
-
return len;
642
-
}
643
-
static DEVICE_ATTR_RW(driver_override);
644
-
645
618
static struct attribute *pci_dev_attrs[] = {
646
619
&dev_attr_power_state.attr,
647
620
&dev_attr_resource.attr,
···
642
669
#ifdef CONFIG_OF
643
670
&dev_attr_devspec.attr,
644
671
#endif
645
-
&dev_attr_driver_override.attr,
646
672
&dev_attr_ari_enabled.attr,
647
673
NULL,
648
674
};
-1
drivers/pci/probe.c
-1
drivers/pci/probe.c
+2
-3
drivers/vfio/pci/vfio_pci_core.c
+2
-3
drivers/vfio/pci/vfio_pci_core.c
···
1987
1987
pdev->is_virtfn && physfn == vdev->pdev) {
1988
1988
pci_info(vdev->pdev, "Captured SR-IOV VF %s driver_override\n",
1989
1989
pci_name(pdev));
1990
-
pdev->driver_override = kasprintf(GFP_KERNEL, "%s",
1991
-
vdev->vdev.ops->name);
1992
-
WARN_ON(!pdev->driver_override);
1990
+
WARN_ON(device_set_driver_override(&pdev->dev,
1991
+
vdev->vdev.ops->name));
1993
1992
} else if (action == BUS_NOTIFY_BOUND_DRIVER &&
1994
1993
pdev->is_virtfn && physfn == vdev->pdev) {
1995
1994
struct pci_driver *drv = pci_dev_driver(pdev);
+4
-2
drivers/xen/xen-pciback/pci_stub.c
+4
-2
drivers/xen/xen-pciback/pci_stub.c
···
598
598
return err;
599
599
}
600
600
601
+
static struct pci_driver xen_pcibk_pci_driver;
602
+
601
603
/* Called when 'bind'. This means we must _NOT_ call pci_reset_function or
602
604
* other functions that take the sysfs lock. */
603
605
static int pcistub_probe(struct pci_dev *dev, const struct pci_device_id *id)
···
611
609
612
610
match = pcistub_match(dev);
613
611
614
-
if ((dev->driver_override &&
615
-
!strcmp(dev->driver_override, PCISTUB_DRIVER_NAME)) ||
612
+
if (device_match_driver_override(&dev->dev,
613
+
&xen_pcibk_pci_driver.driver) > 0 ||
616
614
match) {
617
615
618
616
if (dev->hdr_type != PCI_HEADER_TYPE_NORMAL
-6
include/linux/pci.h
-6
include/linux/pci.h
···
575
575
u8 supported_speeds; /* Supported Link Speeds Vector */
576
576
phys_addr_t rom; /* Physical address if not from BAR */
577
577
size_t romlen; /* Length if not from BAR */
578
-
/*
579
-
* Driver name to force a match. Do not set directly, because core
580
-
* frees it. Use driver_set_override() to set or clear it.
581
-
*/
582
-
const char *driver_override;
583
-
584
578
unsigned long priv_flags; /* Private flags for the PCI driver */
585
579
586
580
/* These methods index pci_reset_fn_methods[] */