From: Michal Wajdeczko Date: Tue, 22 Jul 2025 14:10:55 +0000 (+0200) Subject: drm/xe/configfs: Enforce canonical device names X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=400a6da1e967c4f117e4757412df06dcfaea0e6a;p=users%2Fjedix%2Flinux-maple.git drm/xe/configfs: Enforce canonical device names 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 Cc: Lucas De Marchi Reviewed-by: Lucas De Marchi Link: https://lore.kernel.org/r/20250722141059.30707-3-michal.wajdeczko@intel.com Signed-off-by: Lucas De Marchi --- diff --git a/drivers/gpu/drm/xe/xe_configfs.c b/drivers/gpu/drm/xe/xe_configfs.c index e9b46a2d0019..f5ce48a0adc8 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);