Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754512AbbGFKJg (ORCPT ); Mon, 6 Jul 2015 06:09:36 -0400 Received: from mail-wg0-f45.google.com ([74.125.82.45]:33207 "EHLO mail-wg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754031AbbGFKJ3 (ORCPT ); Mon, 6 Jul 2015 06:09:29 -0400 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= To: Darren Hart , Matthew Garrett Cc: platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, Gabriele Mazzotta , =?UTF-8?q?Pali=20Roh=C3=A1r?= Subject: [PATCH v2 1/3] dell-laptop: Clear buffer before each SMBIOS call Date: Mon, 6 Jul 2015 12:08:55 +0200 Message-Id: <1436177337-13654-1-git-send-email-pali.rohar@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1435774101-12329-1-git-send-email-pali.rohar@gmail.com> References: <1435774101-12329-1-git-send-email-pali.rohar@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2035 Lines: 63 Make sure that before initializing SMBIOS call input buffer does not contain any garbage (e.g. values from previous SMBIOS call). This fix problem with passing undefined/random parameters to SMBIOS functions. Signed-off-by: Pali Rohár --- drivers/platform/x86/dell-laptop.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c index 35758cb..2caefb2 100644 --- a/drivers/platform/x86/dell-laptop.c +++ b/drivers/platform/x86/dell-laptop.c @@ -310,10 +310,15 @@ static DEFINE_MUTEX(buffer_mutex); static int hwswitch_state; +static void clear_buffer(void) +{ + memset(buffer, 0, sizeof(struct calling_interface_buffer)); +} + static void get_buffer(void) { mutex_lock(&buffer_mutex); - memset(buffer, 0, sizeof(struct calling_interface_buffer)); + clear_buffer(); } static void release_buffer(void) @@ -557,6 +562,8 @@ static int dell_rfkill_set(void *data, bool blocked) !(buffer->output[1] & BIT(16))) disable = 1; + clear_buffer(); + buffer->input[0] = (1 | (radio<<8) | (disable << 16)); dell_send_request(buffer, 17, 11); @@ -571,6 +578,7 @@ static void dell_rfkill_update_sw_state(struct rfkill *rfkill, int radio, if (status & BIT(0)) { /* Has hw-switch, sync sw_state to BIOS */ int block = rfkill_blocked(rfkill); + clear_buffer(); buffer->input[0] = (1 | (radio << 8) | (block << 16)); dell_send_request(buffer, 17, 11); } else { @@ -773,6 +781,7 @@ static int __init dell_setup_rfkill(void) get_buffer(); dell_send_request(buffer, 17, 11); status = buffer->output[1]; + clear_buffer(); buffer->input[0] = 0x2; dell_send_request(buffer, 17, 11); hwswitch_state = buffer->output[1]; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/