From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dan Rosenberg Subject: [PATCH] sound/oss/opl3: validate voice and channel indexes Date: Wed, 23 Mar 2011 11:42:57 -0400 Message-ID: <1300894977.1968.37.camel@dan> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: perex@perex.cz, tiwai@suse.de Cc: alsa-devel@alsa-project.org, security@kernel.org, linux-kernel@vger.kernel.org List-Id: alsa-devel@alsa-project.org User-controllable indexes for voice and channel values may cause reading and writing beyond the bounds of their respective arrays, leading to potentially exploitable memory corruption. Validate these indexes. Signed-off-by: Dan Rosenberg Cc: stable@kernel.org --- sound/oss/opl3.c | 15 +++++++++++++-- 1 files changed, 13 insertions(+), 2 deletions(-) diff --git a/sound/oss/opl3.c b/sound/oss/opl3.c index 938c48c..e9d443e 100644 --- a/sound/oss/opl3.c +++ b/sound/oss/opl3.c @@ -849,6 +849,10 @@ static int opl3_load_patch(int dev, int format, const char __user *addr, static void opl3_panning(int dev, int voice, int value) { + + if (voice < 0 || voice >= devc->nr_voice) + return; + devc->voc[voice].panning = value; } @@ -1066,8 +1070,15 @@ static int opl3_alloc_voice(int dev, int chn, int note, struct voice_alloc_info static void opl3_setup_voice(int dev, int voice, int chn) { - struct channel_info *info = - &synth_devs[dev]->chn_info[chn]; + struct channel_info *info; + + if (voice < 0 || voice >= devc->nr_voice) + return; + + if (chn < 0 || chn > 15) + return; + + info = &synth_devs[dev]->chn_info[chn]; opl3_set_instr(dev, voice, info->pgm_num);