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 0D479C433F5 for ; Mon, 13 Dec 2021 10:19:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244824AbhLMKTt (ORCPT ); Mon, 13 Dec 2021 05:19:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238787AbhLMKQa (ORCPT ); Mon, 13 Dec 2021 05:16:30 -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 026C2C0497C8; Mon, 13 Dec 2021 01:55:47 -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 BEB2FB80E20; Mon, 13 Dec 2021 09:55:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E2794C34603; Mon, 13 Dec 2021 09:55:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1639389344; bh=JZokK1IX38ZQX0xQOH972lDk/0kw0DYe0LPRBfNa570=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Uchl/IHwFU0JkwAQcAKAZUr56ZpBQrxroNIvlJdmnS5oRhcz03Z4yJ6gdJq4eudWJ PTIYgINcOTHBnT2fB05/vpBKkLqe3M0cMJAYHo9MW1QGfEu/Mu4BFdGbm3N2ND7Qfa GS2aBBiM7MQaO2DLngnhTeU9+KAilzDFePnAB4/E= 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 5.15 068/171] ALSA: pcm: oss: Limit the period size to 16MB Date: Mon, 13 Dec 2021 10:29:43 +0100 Message-Id: <20211213092947.363252054@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 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 @@ -1962,7 +1962,7 @@ 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;