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 886A1C433EF for ; Mon, 13 Dec 2021 09:32:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233771AbhLMJc1 (ORCPT ); Mon, 13 Dec 2021 04:32:27 -0500 Received: from sin.source.kernel.org ([145.40.73.55]:57498 "EHLO sin.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233749AbhLMJc0 (ORCPT ); Mon, 13 Dec 2021 04:32:26 -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 sin.source.kernel.org (Postfix) with ESMTPS id 56EC8CE0E70; Mon, 13 Dec 2021 09:32:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0943CC341C5; Mon, 13 Dec 2021 09:32:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1639387943; bh=JxDh5+dF5yuAZa4Kyw/coyL1JTx+vvOLIjUo3sieyVY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rxpw8JhUqq20zxYufZjGMa8vstUl/S8/rfSYy/i1EWgbg8XPZUtGwTHpFcdtQ13ce vl74aNhxRMTE+tUIENsf3a35J6MU1sMGsVp0XG8Rf4acaVVQ4xmwnoJgOdJFlQc9jA jtMfXRm8oMYgBJ923I1/BL+VotC0IaHvsxa/pyCY= 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 4.4 13/37] ALSA: pcm: oss: Limit the period size to 16MB Date: Mon, 13 Dec 2021 10:29:51 +0100 Message-Id: <20211213092925.803120967@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211213092925.380184671@linuxfoundation.org> References: <20211213092925.380184671@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: stable@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 @@ -2018,7 +2018,7 @@ 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;