From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965537AbdJQS0d (ORCPT ); Tue, 17 Oct 2017 14:26:33 -0400 Received: from esa7.dell-outbound.iphmx.com ([68.232.153.96]:19818 "EHLO esa7.dell-outbound.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934584AbdJQSWG (ORCPT ); Tue, 17 Oct 2017 14:22:06 -0400 X-LoopCount0: from 10.208.86.39 X-IronPort-AV: E=Sophos;i="5.43,391,1503378000"; d="scan'208";a="161471153" X-DLP: DLP_GlobalPCIDSS From: Mario Limonciello To: dvhart@infradead.org, Andy Shevchenko Cc: LKML , platform-driver-x86@vger.kernel.org, Andy Lutomirski , quasisec@google.com, pali.rohar@gmail.com, rjw@rjwysocki.net, mjg59@google.com, hch@lst.de, Greg KH , Alan Cox , Mario Limonciello Subject: [PATCH v9 02/17] platform/x86: dell-wmi: increase severity of some failures Date: Tue, 17 Oct 2017 13:21:46 -0500 Message-Id: X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is a lot of error checking in place for the format of the WMI descriptor buffer, but some of the potentially raised issues should be considered critical failures. If the buffer size or header don't match, this is a good indication that the buffer format changed in a way that the rest of the data should not be relied upon. For the remaining data set vectors, continue to notate a warning in undefined results, but as those are fields that the descriptor intended to refer to other applications, don't fail if they're new values. Signed-off-by: Mario Limonciello Reviewed-by: Edward O'Callaghan --- drivers/platform/x86/dell-wmi.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c index 1fbef560ca67..2cfaaa8faf0a 100644 --- a/drivers/platform/x86/dell-wmi.c +++ b/drivers/platform/x86/dell-wmi.c @@ -657,17 +657,18 @@ static int dell_wmi_check_descriptor_buffer(struct wmi_device *wdev) dev_err(&wdev->dev, "Dell descriptor buffer has invalid length (%d)\n", obj->buffer.length); - if (obj->buffer.length < 16) { - ret = -EINVAL; - goto out; - } + ret = -EINVAL; + goto out; } buffer = (u32 *)obj->buffer.pointer; - if (buffer[0] != 0x4C4C4544 && buffer[1] != 0x494D5720) - dev_warn(&wdev->dev, "Dell descriptor buffer has invalid signature (%*ph)\n", + if (buffer[0] != 0x4C4C4544 && buffer[1] != 0x494D5720) { + dev_err(&wdev->dev, "Dell descriptor buffer has invalid signature (%*ph)\n", 8, buffer); + ret = -EINVAL; + goto out; + } if (buffer[2] != 0 && buffer[2] != 1) dev_warn(&wdev->dev, "Dell descriptor buffer has unknown version (%d)\n", -- 2.14.1