From patchwork Thu Nov 9 13:49:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nikita Kiryushin X-Patchwork-Id: 742615 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 5D6D61E529 for ; Thu, 9 Nov 2023 14:01:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=none X-Greylist: delayed 733 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Thu, 09 Nov 2023 06:01:44 PST Received: from relay163.nicmail.ru (relay163.nicmail.ru [91.189.117.7]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB35D2D77 for ; Thu, 9 Nov 2023 06:01:44 -0800 (PST) Received: from [10.28.138.148] (port=33836 helo=[192.168.95.111]) by relay.hosting.mail.nic.ru with esmtp (Exim 5.55) (envelope-from ) id 1r15PS-0005CE-BH; Thu, 09 Nov 2023 16:49:26 +0300 Received: from [87.245.155.195] (account kiryushin@ancud.ru HELO [192.168.95.111]) by incarp1101.mail.hosting.nic.ru (Exim 5.55) with id 1r15PS-00E7MJ-1K; Thu, 09 Nov 2023 16:49:26 +0300 Message-ID: <262a7526-9e0a-4688-85b4-8546a6580ad0@ancud.ru> Date: Thu, 9 Nov 2023 16:49:25 +0300 Precedence: bulk X-Mailing-List: linux-acpi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Nikita Kiryushin Subject: [PATCH] ACPI: video: check for error while searching for backlit device parent To: "Rafael J. Wysocki" Cc: Len Brown , Matthew Garrett , Andrew Morton , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org Content-Language: en-US X-MS-Exchange-Organization-SCL: -1 If acpi_get_parent called in acpi_video_dev_register_backlight fails (for example, acpi_ut_acquire_mutex fails inside acpi_get_parent), this can lead to incorrect (uninitialized) acpi_parent handler being passed to acpi_get_pci_dev for detecting parent pci device. Check acpi_get_parent result and set parent device only in case of success. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 9661e92c10a9 ("acpi: tie ACPI backlight devices to PCI devices if possible") Signed-off-by: Nikita Kiryushin --- drivers/acpi/acpi_video.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) 2.34.1 diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c index 0b7a01f38b65..1d550887349a 100644 --- a/drivers/acpi/acpi_video.c +++ b/drivers/acpi/acpi_video.c @@ -1717,12 +1717,12 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device) return; count++; - acpi_get_parent(device->dev->handle, &acpi_parent); - - pdev = acpi_get_pci_dev(acpi_parent); - if (pdev) { - parent = &pdev->dev; - pci_dev_put(pdev); + if (ACPI_SUCCESS(acpi_get_parent(device->dev->handle, &acpi_parent))) { + pdev = acpi_get_pci_dev(acpi_parent); + if (pdev) { + parent = &pdev->dev; + pci_dev_put(pdev); + } } memset(&props, 0, sizeof(struct backlight_properties)); --