From: Danilo Krummrich <dakr@kernel.org> stable inclusion from stable-v6.12.80 commit 9a6086d2a828dd2ff74cf9abcae456670febd71f category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14259 CVE: CVE-2026-31527 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 2b38efc05bf7a8568ec74bfffea0f5cfa62bc01d ] 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: 3d713e0e382e ("driver core: platform: add device binding path 'driver_override'") Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/20260303115720.48783-5-dakr@kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Conflicts: drivers/base/platform.c drivers/bus/simple-pm-bus.c drivers/clk/imx/clk-scu.c [Context Conflicts] Signed-off-by: Lin Ruifeng <linruifeng4@huawei.com> --- drivers/base/platform.c | 37 +++++---------------------------- drivers/bus/simple-pm-bus.c | 4 ++-- drivers/clk/imx/clk-scu.c | 3 +-- drivers/slimbus/qcom-ngd-ctrl.c | 6 ++---- include/linux/platform_device.h | 5 ----- sound/soc/samsung/i2s.c | 6 +++--- 6 files changed, 13 insertions(+), 48 deletions(-) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 76bfcba25003..1cc9a876b3cd 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -561,7 +561,6 @@ static void platform_device_release(struct device *dev) kfree(pa->pdev.dev.platform_data); kfree(pa->pdev.mfd_cell); kfree(pa->pdev.resource); - kfree(pa->pdev.driver_override); kfree(pa); } @@ -1265,38 +1264,9 @@ static ssize_t numa_node_show(struct device *dev, } static DEVICE_ATTR_RO(numa_node); -static ssize_t driver_override_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct platform_device *pdev = to_platform_device(dev); - ssize_t len; - - device_lock(dev); - len = sysfs_emit(buf, "%s\n", pdev->driver_override); - device_unlock(dev); - - return len; -} - -static ssize_t driver_override_store(struct device *dev, - struct device_attribute *attr, - const char *buf, size_t count) -{ - struct platform_device *pdev = to_platform_device(dev); - int ret; - - ret = driver_set_override(dev, &pdev->driver_override, buf, count); - if (ret) - return ret; - - return count; -} -static DEVICE_ATTR_RW(driver_override); - static struct attribute *platform_dev_attrs[] = { &dev_attr_modalias.attr, &dev_attr_numa_node.attr, - &dev_attr_driver_override.attr, NULL, }; @@ -1336,10 +1306,12 @@ static int platform_match(struct device *dev, struct device_driver *drv) { struct platform_device *pdev = to_platform_device(dev); struct platform_driver *pdrv = to_platform_driver(drv); + int ret; /* When driver_override is set, only bind to the matching driver */ - if (pdev->driver_override) - return !strcmp(pdev->driver_override, drv->name); + ret = device_match_driver_override(dev, drv); + if (ret >= 0) + return ret; /* Attempt an OF style match first */ if (of_driver_match_device(dev, drv)) @@ -1482,6 +1454,7 @@ static const struct dev_pm_ops platform_dev_pm_ops = { struct bus_type platform_bus_type = { .name = "platform", .dev_groups = platform_dev_groups, + .driver_override = true, .match = platform_match, .uevent = platform_uevent, .probe = platform_probe, diff --git a/drivers/bus/simple-pm-bus.c b/drivers/bus/simple-pm-bus.c index aafcc481de91..cb71774400d4 100644 --- a/drivers/bus/simple-pm-bus.c +++ b/drivers/bus/simple-pm-bus.c @@ -36,7 +36,7 @@ static int simple_pm_bus_probe(struct platform_device *pdev) * that's not listed in simple_pm_bus_of_match. We don't want to do any * of the simple-pm-bus tasks for these devices, so return early. */ - if (pdev->driver_override) + if (device_has_driver_override(&pdev->dev)) return 0; match = of_match_device(dev->driver->of_match_table, dev); @@ -78,7 +78,7 @@ static int simple_pm_bus_remove(struct platform_device *pdev) { const void *data = of_device_get_match_data(&pdev->dev); - if (pdev->driver_override || data) + if (device_has_driver_override(&pdev->dev) || data) return 0; dev_dbg(&pdev->dev, "%s\n", __func__); diff --git a/drivers/clk/imx/clk-scu.c b/drivers/clk/imx/clk-scu.c index 564f549ec204..3a68576cdae7 100644 --- a/drivers/clk/imx/clk-scu.c +++ b/drivers/clk/imx/clk-scu.c @@ -700,8 +700,7 @@ struct clk_hw *imx_clk_scu_alloc_dev(const char *name, return ERR_PTR(ret); } - ret = driver_set_override(&pdev->dev, &pdev->driver_override, - "imx-scu-clk", strlen("imx-scu-clk")); + ret = device_set_driver_override(&pdev->dev, "imx-scu-clk"); if (ret) { platform_device_put(pdev); return ERR_PTR(ret); diff --git a/drivers/slimbus/qcom-ngd-ctrl.c b/drivers/slimbus/qcom-ngd-ctrl.c index fe3a96577f31..d0d289c49c8d 100644 --- a/drivers/slimbus/qcom-ngd-ctrl.c +++ b/drivers/slimbus/qcom-ngd-ctrl.c @@ -1537,10 +1537,8 @@ static int of_qcom_slim_ngd_register(struct device *parent, ngd->id = id; ngd->pdev->dev.parent = parent; - ret = driver_set_override(&ngd->pdev->dev, - &ngd->pdev->driver_override, - QCOM_SLIM_NGD_DRV_NAME, - strlen(QCOM_SLIM_NGD_DRV_NAME)); + ret = device_set_driver_override(&ngd->pdev->dev, + QCOM_SLIM_NGD_DRV_NAME); if (ret) { platform_device_put(ngd->pdev); kfree(ngd); diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 7a41c72c1959..8828b0d275d7 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -31,11 +31,6 @@ struct platform_device { struct resource *resource; const struct platform_device_id *id_entry; - /* - * 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; /* MFD cell pointer */ struct mfd_cell *mfd_cell; diff --git a/sound/soc/samsung/i2s.c b/sound/soc/samsung/i2s.c index 3af48c9b5ab7..925782e67673 100644 --- a/sound/soc/samsung/i2s.c +++ b/sound/soc/samsung/i2s.c @@ -1364,10 +1364,10 @@ static int i2s_create_secondary_device(struct samsung_i2s_priv *priv) if (!pdev_sec) return -ENOMEM; - pdev_sec->driver_override = kstrdup("samsung-i2s", GFP_KERNEL); - if (!pdev_sec->driver_override) { + ret = device_set_driver_override(&pdev_sec->dev, "samsung-i2s"); + if (ret) { platform_device_put(pdev_sec); - return -ENOMEM; + return ret; } ret = platform_device_add(pdev_sec); -- 2.43.0