From patchwork Tue Sep 11 11:11:24 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 1437081 Return-Path: X-Original-To: patchwork-linux-media@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id D978FDFAF3 for ; Tue, 11 Sep 2012 11:11:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758234Ab2IKLLu (ORCPT ); Tue, 11 Sep 2012 07:11:50 -0400 Received: from rcsinet15.oracle.com ([148.87.113.117]:37104 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757783Ab2IKLLu (ORCPT ); Tue, 11 Sep 2012 07:11:50 -0400 Received: from ucsinet22.oracle.com (ucsinet22.oracle.com [156.151.31.94]) by rcsinet15.oracle.com (Sentrion-MTA-4.2.2/Sentrion-MTA-4.2.2) with ESMTP id q8BBBNIs007125 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 11 Sep 2012 11:11:24 GMT Received: from acsmt356.oracle.com (acsmt356.oracle.com [141.146.40.156]) by ucsinet22.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id q8BBBMeS002975 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Tue, 11 Sep 2012 11:11:23 GMT Received: from abhmt115.oracle.com (abhmt115.oracle.com [141.146.116.67]) by acsmt356.oracle.com (8.12.11.20060308/8.12.11) with ESMTP id q8BBBMmA001585; Tue, 11 Sep 2012 06:11:22 -0500 Received: from elgon.mountain (/41.212.103.53) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 11 Sep 2012 04:11:21 -0700 Date: Tue, 11 Sep 2012 14:11:24 +0300 From: Dan Carpenter To: Maxim Levitsky Cc: Mauro Carvalho Chehab , linux-media@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [patch v3] [media] rc: divide by zero bugs in s_tx_carrier() Message-ID: <20120911111124.GA22259@elgon.mountain> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20120909222629.GA28355@pequod.mess.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet22.oracle.com [156.151.31.94] Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org "carrier" comes from a get_user() in ir_lirc_ioctl(). We need to test that it's not zero before using it as a divisor. It might have been nice to test for this ir_lirc_ioctl() but the mceusb driver uses zero to disable carrier modulation. The bug in redrat3 is a little more subtle. The ->carrier is passed to mod_freq_to_val() which uses it as a divisor. Signed-off-by: Dan Carpenter --- v2: tried to add the check to ir_lirc_ioctl() but that doesn't work. v3: the same as v1 except that I've added a fix for redrat3 as well. -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/media/rc/ene_ir.c b/drivers/media/rc/ene_ir.c index 647dd95..d05ac15 100644 --- a/drivers/media/rc/ene_ir.c +++ b/drivers/media/rc/ene_ir.c @@ -881,10 +881,13 @@ static int ene_set_tx_mask(struct rc_dev *rdev, u32 tx_mask) static int ene_set_tx_carrier(struct rc_dev *rdev, u32 carrier) { struct ene_device *dev = rdev->priv; - u32 period = 2000000 / carrier; + u32 period; dbg("TX: attempt to set tx carrier to %d kHz", carrier); + if (carrier == 0) + return -EINVAL; + period = 2000000 / carrier; if (period && (period > ENE_CIRMOD_PRD_MAX || period < ENE_CIRMOD_PRD_MIN)) { diff --git a/drivers/media/rc/nuvoton-cir.c b/drivers/media/rc/nuvoton-cir.c index 699eef3..2ea913a 100644 --- a/drivers/media/rc/nuvoton-cir.c +++ b/drivers/media/rc/nuvoton-cir.c @@ -517,6 +517,9 @@ static int nvt_set_tx_carrier(struct rc_dev *dev, u32 carrier) struct nvt_dev *nvt = dev->priv; u16 val; + if (carrier == 0) + return -EINVAL; + nvt_cir_reg_write(nvt, 1, CIR_CP); val = 3000000 / (carrier) - 1; nvt_cir_reg_write(nvt, val & 0xff, CIR_CC); diff --git a/drivers/media/rc/redrat3.c b/drivers/media/rc/redrat3.c index 2878b0e..bf8bc74 100644 --- a/drivers/media/rc/redrat3.c +++ b/drivers/media/rc/redrat3.c @@ -890,6 +890,9 @@ static int redrat3_set_tx_carrier(struct rc_dev *rcdev, u32 carrier) struct device *dev = rr3->dev; rr3_dbg(dev, "Setting modulation frequency to %u", carrier); + if (carrier == 0) + return -EINVAL; + rr3->carrier = carrier; return carrier;