6.17-stable review patch. If anyone has any objections, please let me know.
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From: Michal Wajdeczko michal.wajdeczko@intel.com
[ Upstream commit 400a6da1e967c4f117e4757412df06dcfaea0e6a ]
While we expect config directory names to match PCI device name, currently we are only scanning provided names for domain, bus, device and function numbers, without checking their format. This would pass slightly broken entries like:
/sys/kernel/config/xe/ ├── 0000:00:02.0000000000000 │ └── ... ├── 0000:00:02.0x │ └── ... ├── 0: 0: 2. 0 │ └── ... └── 0:0:2.0 └── ...
To avoid such mistakes, check if the name provided exactly matches the canonical PCI device address format, which we recreated from the parsed BDF data. Also simplify scanf format as it can't really catch all formatting errors.
Signed-off-by: Michal Wajdeczko michal.wajdeczko@intel.com Cc: Lucas De Marchi lucas.demarchi@intel.com Reviewed-by: Lucas De Marchi lucas.demarchi@intel.com Link: https://lore.kernel.org/r/20250722141059.30707-3-michal.wajdeczko@intel.com Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/xe/xe_configfs.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/xe/xe_configfs.c b/drivers/gpu/drm/xe/xe_configfs.c index 58c1f397c68c9..797508cc6eb17 100644 --- a/drivers/gpu/drm/xe/xe_configfs.c +++ b/drivers/gpu/drm/xe/xe_configfs.c @@ -259,12 +259,19 @@ static struct config_group *xe_config_make_device_group(struct config_group *gro unsigned int domain, bus, slot, function; struct xe_config_device *dev; struct pci_dev *pdev; + char canonical[16]; int ret;
- ret = sscanf(name, "%04x:%02x:%02x.%x", &domain, &bus, &slot, &function); + ret = sscanf(name, "%x:%x:%x.%x", &domain, &bus, &slot, &function); if (ret != 4) return ERR_PTR(-EINVAL);
+ ret = scnprintf(canonical, sizeof(canonical), "%04x:%02x:%02x.%d", domain, bus, + PCI_SLOT(PCI_DEVFN(slot, function)), + PCI_FUNC(PCI_DEVFN(slot, function))); + if (ret != 12 || strcmp(name, canonical)) + return ERR_PTR(-EINVAL); + pdev = pci_get_domain_bus_and_slot(domain, bus, PCI_DEVFN(slot, function)); if (!pdev) return ERR_PTR(-ENODEV);