From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753225AbZKPPwg (ORCPT ); Mon, 16 Nov 2009 10:52:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753000AbZKPPwf (ORCPT ); Mon, 16 Nov 2009 10:52:35 -0500 Received: from fg-out-1718.google.com ([72.14.220.156]:58744 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751882AbZKPPwe (ORCPT ); Mon, 16 Nov 2009 10:52:34 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:subject :content-type:content-transfer-encoding; b=MkKJTpPLcvDv0BUKquKnhr/Ke94OTL8MN7baXF2wV66Ts+yGPWW/4uqwt91DbRGB+o kwAwZvxBN3mm4sg80cy7uoGohT4X59Rh0tKKvlRcikkHtQ/RKIeMnNC4mKPb/VhH0t6a dkJik3bSGAUyZYYbnKhpOUSffitod1C1EQO7Y= Message-ID: <4B01782E.80802@gmail.com> Date: Mon, 16 Nov 2009 17:05:02 +0100 From: Roel Kluin User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.4pre) Gecko/20091014 Fedora/3.0-2.8.b4.fc11 Thunderbird/3.0b4 MIME-Version: 1.0 To: Jaroslav Kysela , Takashi Iwai , alsa-devel@alsa-project.org, Andrew Morton , LKML Subject: [PATCH] OSS: keep index within bounds of midi_devs[] Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When the {orig,midi}_dev equals num_midis, that's one too large already. Signed-off-by: Roel Kluin --- In MIDIbuf_open() sound/oss/midibuf.c:166 if (num_midis > MAX_MIDI_DEV) { printk(KERN_ERR "midi: Too many midi interfaces\n"); num_midis = MAX_MIDI_DEV; } num_midis is at most MAX_MIDI_DEV. `git grep -n MAX_MIDI_DEV' and note that when the index equals num_midis this causes reads/writes outside array bounds for midi_devs, midi2synth, dev_conf and others (below check in patch). sound/oss/midi_synth.c | 2 +- sound/oss/mpu401.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/sound/oss/midi_synth.c b/sound/oss/midi_synth.c index 9e45098..3bc7104 100644 --- a/sound/oss/midi_synth.c +++ b/sound/oss/midi_synth.c @@ -426,7 +426,7 @@ midi_synth_open(int dev, int mode) int err; struct midi_input_info *inc; - if (orig_dev < 0 || orig_dev > num_midis || midi_devs[orig_dev] == NULL) + if (orig_dev < 0 || orig_dev >= num_midis || midi_devs[orig_dev] == NULL) return -ENXIO; midi2synth[orig_dev] = dev; diff --git a/sound/oss/mpu401.c b/sound/oss/mpu401.c index 734b8f9..0af9d24 100644 --- a/sound/oss/mpu401.c +++ b/sound/oss/mpu401.c @@ -770,7 +770,7 @@ static int mpu_synth_ioctl(int dev, unsigned int cmd, void __user *arg) midi_dev = synth_devs[dev]->midi_dev; - if (midi_dev < 0 || midi_dev > num_midis || midi_devs[midi_dev] == NULL) + if (midi_dev < 0 || midi_dev >= num_midis || midi_devs[midi_dev] == NULL) return -ENXIO; devc = &dev_conf[midi_dev];