From mboxrd@z Thu Jan 1 00:00:00 1970 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 5C17DC4332F for ; Mon, 13 Dec 2021 09:49:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235118AbhLMJtI (ORCPT ); Mon, 13 Dec 2021 04:49:08 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235303AbhLMJod (ORCPT ); Mon, 13 Dec 2021 04:44:33 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DFFDC061D5E; Mon, 13 Dec 2021 01:40:50 -0800 (PST) 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 C9ED2B80E19; Mon, 13 Dec 2021 09:40:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06CC1C00446; Mon, 13 Dec 2021 09:40:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1639388448; bh=+PfCJkbJZsskR/GCh/m+ZdAW7iA2MMayYcLX+c/hYpk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=EhCFpXuwauT4z2IkF6617okCEKKevUN6sJNSS0O9KgcWp6+jiji1NTu65ATm7DwoB cf+34QFTT+/QQ7742RqIzAqtHKoiomigOrPhXlarPQLdJPIxelqZh39rzTGLhK4zQz HC0a0a28tAa8qX78/OUKGWxnXq9BHmLSqQdl70Fk= 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 4.19 26/74] ALSA: pcm: oss: Limit the period size to 16MB Date: Mon, 13 Dec 2021 10:29:57 +0100 Message-Id: <20211213092931.680864627@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211213092930.763200615@linuxfoundation.org> References: <20211213092930.763200615@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 8839c8c0f77ab8fc0463f4ab8b37fca3f70677c2 upstream. Set the practical limit to the period size (the fragment shift in OSS) instead of a full 31bit; a too large value could lead to the exhaust of memory as we allocate temporary buffers of the period size, too. As of this patch, we set to 16MB limit, which should cover all use cases. 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/20211201073606.11660-3-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/oss/pcm_oss.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/core/oss/pcm_oss.c +++ b/sound/core/oss/pcm_oss.c @@ -1967,7 +1967,7 @@ static int snd_pcm_oss_set_fragment1(str if (runtime->oss.subdivision || runtime->oss.fragshift) return -EINVAL; fragshift = val & 0xffff; - if (fragshift >= 31) + if (fragshift >= 25) /* should be large enough */ return -EINVAL; runtime->oss.fragshift = fragshift; runtime->oss.maxfrags = (val >> 16) & 0xffff;