Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0969EC433EF for ; Mon, 13 Dec 2021 10:00:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236656AbhLMKAB (ORCPT ); Mon, 13 Dec 2021 05:00:01 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:41598 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237407AbhLMJzo (ORCPT ); Mon, 13 Dec 2021 04:55:44 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CC692B80E23; Mon, 13 Dec 2021 09:55:42 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B2D5C34600; Mon, 13 Dec 2021 09:55:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1639389341; bh=nZULYzr+I9ZBDLmax1pe4YX3kNbyD0jEs3DKzJC9gu8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RUL9y3OWfQvz/nKIDHbKsUj+0qaMyS2hC6s7oVRM5YktHO2pEF2T60RnYkW8IaF2H +yvJ9jl0UwZAbb+WeqJrVOz7Q8gFEoKQAAEzFrfn0Upk2DpRWx258WJ3UDbDaox4jV Afq4R0Q4FseCNsMfm8HqHGo9+SuSR9a2b2ySa8a0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+bb348e9f9a954d42746f@syzkaller.appspotmail.com, Bixuan Cui , Takashi Iwai Subject: [PATCH 5.15 067/171] ALSA: pcm: oss: Fix negative period/buffer sizes Date: Mon, 13 Dec 2021 10:29:42 +0100 Message-Id: <20211213092947.330992093@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211213092945.091487407@linuxfoundation.org> References: <20211213092945.091487407@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Takashi Iwai commit 9d2479c960875ca1239bcb899f386970c13d9cfe upstream. The period size calculation in OSS layer may receive a negative value as an error, but the code there assumes only the positive values and handle them with size_t. Due to that, a too big value may be passed to the lower layers. This patch changes the code to handle with ssize_t and adds the proper error checks appropriately. Reported-by: syzbot+bb348e9f9a954d42746f@syzkaller.appspotmail.com Reported-by: Bixuan Cui Cc: Link: https://lore.kernel.org/r/1638270978-42412-1-git-send-email-cuibixuan@linux.alibaba.com Link: https://lore.kernel.org/r/20211201073606.11660-2-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/oss/pcm_oss.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) --- a/sound/core/oss/pcm_oss.c +++ b/sound/core/oss/pcm_oss.c @@ -147,7 +147,7 @@ snd_pcm_hw_param_value_min(const struct * * Return the maximum value for field PAR. */ -static unsigned int +static int snd_pcm_hw_param_value_max(const struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var, int *dir) { @@ -682,18 +682,24 @@ static int snd_pcm_oss_period_size(struc struct snd_pcm_hw_params *oss_params, struct snd_pcm_hw_params *slave_params) { - size_t s; - size_t oss_buffer_size, oss_period_size, oss_periods; - size_t min_period_size, max_period_size; + ssize_t s; + ssize_t oss_buffer_size; + ssize_t oss_period_size, oss_periods; + ssize_t min_period_size, max_period_size; struct snd_pcm_runtime *runtime = substream->runtime; size_t oss_frame_size; oss_frame_size = snd_pcm_format_physical_width(params_format(oss_params)) * params_channels(oss_params) / 8; + oss_buffer_size = snd_pcm_hw_param_value_max(slave_params, + SNDRV_PCM_HW_PARAM_BUFFER_SIZE, + NULL); + if (oss_buffer_size <= 0) + return -EINVAL; oss_buffer_size = snd_pcm_plug_client_size(substream, - snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_BUFFER_SIZE, NULL)) * oss_frame_size; - if (!oss_buffer_size) + oss_buffer_size * oss_frame_size); + if (oss_buffer_size <= 0) return -EINVAL; oss_buffer_size = rounddown_pow_of_two(oss_buffer_size); if (atomic_read(&substream->mmap_count)) { @@ -730,7 +736,7 @@ static int snd_pcm_oss_period_size(struc min_period_size = snd_pcm_plug_client_size(substream, snd_pcm_hw_param_value_min(slave_params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, NULL)); - if (min_period_size) { + if (min_period_size > 0) { min_period_size *= oss_frame_size; min_period_size = roundup_pow_of_two(min_period_size); if (oss_period_size < min_period_size) @@ -739,7 +745,7 @@ static int snd_pcm_oss_period_size(struc max_period_size = snd_pcm_plug_client_size(substream, snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, NULL)); - if (max_period_size) { + if (max_period_size > 0) { max_period_size *= oss_frame_size; max_period_size = rounddown_pow_of_two(max_period_size); if (oss_period_size > max_period_size) @@ -752,7 +758,7 @@ static int snd_pcm_oss_period_size(struc oss_periods = substream->oss.setup.periods; s = snd_pcm_hw_param_value_max(slave_params, SNDRV_PCM_HW_PARAM_PERIODS, NULL); - if (runtime->oss.maxfrags && s > runtime->oss.maxfrags) + if (s > 0 && runtime->oss.maxfrags && s > runtime->oss.maxfrags) s = runtime->oss.maxfrags; if (oss_periods > s) oss_periods = s;