From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0B80E33D4E9; Wed, 20 May 2026 17:17:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297440; cv=none; b=FydMkGxnAemWhfbbnEDSjfVdzTl+Rd3t4CwtcBru3W4xfiAW9FmajotclLklm1vriRCrz0eNpTXg3OxoD+r1XFXrWn6I4BBP6SjdM3ghMB9pqP+TH0cO2cdC159Ji8mKERHM5vO42ifZx3mJhwOlw6eLakhKbMsY9nBM3dF0lDk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779297440; c=relaxed/simple; bh=dFKZDYioTUdcMqumyxhhrQd/VwVRsyBZO9Hqsa/3I4k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=n6n9nQ+oDYm+b1i6Es6bEFhE3Vdc+l6L4p/LOwvQ0HxSEE1fHX5uXwMKVtfzIiiDpAXGWUR/WstmbsxC/89dMMbYc6aGZvj56MILfQu7CJFt33GmfeliwF8rkqIViDMeUy4CT/Iyq4s5EOktW8kZDWJf3X3qTtDHtFqLAt2GmEg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UlU5jdA+; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="UlU5jdA+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 689011F00893; Wed, 20 May 2026 17:17:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779297438; bh=Tcg2dkYHEM/xLoqYeVSLNY4T8Nb+aQQzwNW6+L4/jwo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=UlU5jdA+P5O2f8DnUG/1BZ9YKAB7a3gubGmE37eE0YU+8D+m0eBZXhe3g3Ny6mxBM X5rCnYFQFVm69UYJF6Swh23w4NM2t2N9zWGSxcl8PpmshmYIjZ45rm7gD2My3T0a/k 3FXfQX+zsv7wT7nxBCIA4UKNQ6HaWxjgKbNbtARY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gui-Dong Han , Armin Wolf , =?UTF-8?q?Ilpo=20J=C3=A4rvinen?= , Danilo Krummrich , Sasha Levin Subject: [PATCH 6.18 031/957] platform/wmi: use generic driver_override infrastructure Date: Wed, 20 May 2026 18:08:34 +0200 Message-ID: <20260520162135.234488860@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162134.554764788@linuxfoundation.org> References: <20260520162134.554764788@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Danilo Krummrich [ Upstream commit 8a700b1fc94df4d847a04f14ebc7f8532592b367 ] 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 Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220789 Fixes: 12046f8c77e0 ("platform/x86: wmi: Add driver_override support") Reviewed-by: Armin Wolf Acked-by: Ilpo Järvinen Link: https://patch.msgid.link/20260324005919.2408620-7-dakr@kernel.org Signed-off-by: Danilo Krummrich Signed-off-by: Sasha Levin --- drivers/platform/x86/wmi.c | 36 +++++------------------------------- include/linux/wmi.h | 4 ---- 2 files changed, 5 insertions(+), 35 deletions(-) diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c index 4e86a422f05f1..6f8e96476fd07 100644 --- a/drivers/platform/x86/wmi.c +++ b/drivers/platform/x86/wmi.c @@ -702,39 +702,11 @@ static ssize_t expensive_show(struct device *dev, } static DEVICE_ATTR_RO(expensive); -static ssize_t driver_override_show(struct device *dev, struct device_attribute *attr, - char *buf) -{ - struct wmi_device *wdev = to_wmi_device(dev); - ssize_t ret; - - device_lock(dev); - ret = sysfs_emit(buf, "%s\n", wdev->driver_override); - device_unlock(dev); - - return ret; -} - -static ssize_t driver_override_store(struct device *dev, struct device_attribute *attr, - const char *buf, size_t count) -{ - struct wmi_device *wdev = to_wmi_device(dev); - int ret; - - ret = driver_set_override(dev, &wdev->driver_override, buf, count); - if (ret < 0) - return ret; - - return count; -} -static DEVICE_ATTR_RW(driver_override); - static struct attribute *wmi_attrs[] = { &dev_attr_modalias.attr, &dev_attr_guid.attr, &dev_attr_instance_count.attr, &dev_attr_expensive.attr, - &dev_attr_driver_override.attr, NULL }; ATTRIBUTE_GROUPS(wmi); @@ -803,7 +775,6 @@ static void wmi_dev_release(struct device *dev) { struct wmi_block *wblock = dev_to_wblock(dev); - kfree(wblock->dev.driver_override); kfree(wblock); } @@ -812,10 +783,12 @@ static int wmi_dev_match(struct device *dev, const struct device_driver *driver) const struct wmi_driver *wmi_driver = to_wmi_driver(driver); struct wmi_block *wblock = dev_to_wblock(dev); const struct wmi_device_id *id = wmi_driver->id_table; + int ret; /* When driver_override is set, only bind to the matching driver */ - if (wblock->dev.driver_override) - return !strcmp(wblock->dev.driver_override, driver->name); + ret = device_match_driver_override(dev, driver); + if (ret >= 0) + return ret; if (id == NULL) return 0; @@ -936,6 +909,7 @@ static struct class wmi_bus_class = { static const struct bus_type wmi_bus_type = { .name = "wmi", .dev_groups = wmi_groups, + .driver_override = true, .match = wmi_dev_match, .uevent = wmi_dev_uevent, .probe = wmi_dev_probe, diff --git a/include/linux/wmi.h b/include/linux/wmi.h index 10751c8e5e6a0..c20bb22133381 100644 --- a/include/linux/wmi.h +++ b/include/linux/wmi.h @@ -16,16 +16,12 @@ * struct wmi_device - WMI device structure * @dev: Device associated with this WMI device * @setable: True for devices implementing the Set Control Method - * @driver_override: Driver name to force a match; do not set directly, - * because core frees it; use driver_set_override() to - * set or clear it. * * This represents WMI devices discovered by the WMI driver core. */ struct wmi_device { struct device dev; bool setable; - const char *driver_override; }; /** -- 2.53.0