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 82516C433FE for ; Mon, 13 Dec 2021 09:37:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233739AbhLMJhy (ORCPT ); Mon, 13 Dec 2021 04:37:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234638AbhLMJgb (ORCPT ); Mon, 13 Dec 2021 04:36:31 -0500 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CA3EC0617A2; Mon, 13 Dec 2021 01:36:28 -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 sin.source.kernel.org (Postfix) with ESMTPS id A8A07CE0E82; Mon, 13 Dec 2021 09:36:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52BA2C00446; Mon, 13 Dec 2021 09:36:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1639388184; bh=+PfCJkbJZsskR/GCh/m+ZdAW7iA2MMayYcLX+c/hYpk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OKupRid35xfXOsWUpIG0ZtqtShyTlGo/HjAdVvRUz4Wxfg36BGCbWDATOilRYNw4L /JxHnHIryLyqXAmdxdpZvq/D7QNUBP6q/vnSN0VhxAo534cn8LS91lcVfx/XGLbKhh xQy22kJaBiz/nvcq+JjIV56oDEX6+aCOERLNokS0= 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 4.14 16/53] ALSA: pcm: oss: Limit the period size to 16MB Date: Mon, 13 Dec 2021 10:29:55 +0100 Message-Id: <20211213092928.901248256@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20211213092928.349556070@linuxfoundation.org> References: <20211213092928.349556070@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;