From nobody Sun Jun 14 14:31:22 2026 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) (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 228A01E9906; Fri, 3 Apr 2026 09:03:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.187 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775206983; cv=none; b=gLsFjR6O9n1ksH1kPkb4Ra0LRb8+oPuSPJIHIjj6KJGJU9gt8yZQ9nXjpTeGZcYdBT0m+XwRMD0NNpGwe/WiKBWi3oGOv1KCmE3xWbR78LPUm1PqnvZURJtmRazj8HWbN+nmRXQaJRdC3cQzTHKZ25FbU494Xxvc2Q4eMSmpOZk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775206983; c=relaxed/simple; bh=oHgnLsESaBzRthoqqqnf/65q1igUK2snZTuYNKRSvp8=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=gu17JeSTmnGhwTw+EAW2ixx7upXsly/PzNEWVUewZ/1TXQTR1eqfwgDdFkSkETqA8uibY1+ZdtE6K29dixZM/16a78yf4Z/hVuIZs6u0zVylKdzCqjD+7DuEe0zi9jaweD19bO2okmXvSeIOsPIV6O/K633BZn67DziLwIJHtA0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=h-partners.com; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b=kSXOA/yB; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b=kSXOA/yB; arc=none smtp.client-ip=45.249.212.187 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=h-partners.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b="kSXOA/yB"; dkim=pass (1024-bit key) header.d=h-partners.com header.i=@h-partners.com header.b="kSXOA/yB" dkim-signature: v=1; a=rsa-sha256; d=h-partners.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=anOT8bGurbxJptjoEKZ9kahhNJjJfa6fle0uyAj5Kfg=; b=kSXOA/yB8dxuRwSYPfihcWkqqJZtmTpX+9u4odSGiWi1mGq1Dv3FznK5lf4gI0meMd4gU0esJ Qedum3ktzSbjOwh83//riv+PyEQ6Qxi1Ti78A+cTdn8/eFYDKLAP4hFBtJPn/DSeMWSbsEIIhuO 9AaqGU30GpRV9DORnvs61bE= Received: from canpmsgout03.his.huawei.com (unknown [172.19.92.159]) by szxga01-in.huawei.com (SkyGuard) with ESMTPS id 4fnCRL38rsz1BG6X; Fri, 3 Apr 2026 17:02:38 +0800 (CST) dkim-signature: v=1; a=rsa-sha256; d=h-partners.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=anOT8bGurbxJptjoEKZ9kahhNJjJfa6fle0uyAj5Kfg=; b=kSXOA/yB8dxuRwSYPfihcWkqqJZtmTpX+9u4odSGiWi1mGq1Dv3FznK5lf4gI0meMd4gU0esJ Qedum3ktzSbjOwh83//riv+PyEQ6Qxi1Ti78A+cTdn8/eFYDKLAP4hFBtJPn/DSeMWSbsEIIhuO 9AaqGU30GpRV9DORnvs61bE= Received: from mail.maildlp.com (unknown [172.19.162.197]) by canpmsgout03.his.huawei.com (SkyGuard) with ESMTPS id 4fnCJv1XnrzpTJn; Fri, 3 Apr 2026 16:57:03 +0800 (CST) Received: from dggemv705-chm.china.huawei.com (unknown [10.3.19.32]) by mail.maildlp.com (Postfix) with ESMTPS id A82EA40576; Fri, 3 Apr 2026 17:02:54 +0800 (CST) Received: from kwepemn100009.china.huawei.com (7.202.194.112) by dggemv705-chm.china.huawei.com (10.3.19.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 3 Apr 2026 17:02:54 +0800 Received: from localhost.localdomain (10.50.163.32) by kwepemn100009.china.huawei.com (7.202.194.112) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Fri, 3 Apr 2026 17:02:53 +0800 From: Huisong Li To: , CC: , , , , , , , , , , Subject: [PATCH] ACPI: processor: idle: Fix NULL pointer dereference in hotplug path Date: Fri, 3 Apr 2026 17:02:53 +0800 Message-ID: <20260403090253.998322-1-lihuisong@huawei.com> X-Mailer: git-send-email 2.33.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: kwepems500002.china.huawei.com (7.221.188.17) To kwepemn100009.china.huawei.com (7.202.194.112) Content-Type: text/plain; charset="utf-8" A cpuidle_device might fail to register during boot, but the system can continue to run. In such cases, acpi_processor_hotplug() can trigger a NULL pointer dereference when accessing the per-cpu acpi_cpuidle_device. So add NULL pointer check for the per-cpu acpi_cpuidle_device in acpi_processor_hotplug. Signed-off-by: Huisong Li --- drivers/acpi/processor_idle.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 479995a4c48a..2adaee0f32ed 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -1267,16 +1267,15 @@ static int acpi_processor_get_power_info(struct acp= i_processor *pr) =20 int acpi_processor_hotplug(struct acpi_processor *pr) { + struct cpuidle_device *dev =3D per_cpu(acpi_cpuidle_device, pr->id); int ret =3D 0; - struct cpuidle_device *dev; =20 if (disabled_by_idle_boot_param()) return 0; =20 - if (!pr->flags.power_setup_done) + if (!pr->flags.power_setup_done || !dev) return -ENODEV; =20 - dev =3D per_cpu(acpi_cpuidle_device, pr->id); cpuidle_pause_and_lock(); cpuidle_disable_device(dev); ret =3D acpi_processor_get_power_info(pr); --=20 2.33.0