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 DA4B8C43219 for ; Mon, 18 Apr 2022 14:17:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244404AbiDROTn (ORCPT ); Mon, 18 Apr 2022 10:19:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344402AbiDROSC (ORCPT ); Mon, 18 Apr 2022 10:18:02 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 15C2649FBD; Mon, 18 Apr 2022 06:13:53 -0700 (PDT) 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 90211B80EE5; Mon, 18 Apr 2022 13:13:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C06CEC385A1; Mon, 18 Apr 2022 13:13:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1650287631; bh=3emzYE6OqH2X4RboyukyTjyLdp+12K93UJSU5EGJ9Eg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sfr+w1N+0Nsfw+ThL683ILA5kqJa9BtuqHMJpIAcm8ghbIfq7JL6ShPbkQ+wpnDoa 2krFyGHbkQVOTbSQISU20KNe5o9ymBMtxnwBFGO+D91pgC3vlupeVbtYn4mSa8ega9 RzoRQV3RrhWfJKhCT79MgxzphjP1pO24AkdBtSo8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Fabio M. De Francesco" , Takashi Iwai , syzbot+205eb15961852c2c5974@syzkaller.appspotmail.com Subject: [PATCH 4.9 214/218] ALSA: pcm: Test for "silence" field in struct "pcm_format_data" Date: Mon, 18 Apr 2022 14:14:40 +0200 Message-Id: <20220418121208.408395990@linuxfoundation.org> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20220418121158.636999985@linuxfoundation.org> References: <20220418121158.636999985@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: Fabio M. De Francesco commit 2f7a26abb8241a0208c68d22815aa247c5ddacab upstream. Syzbot reports "KASAN: null-ptr-deref Write in snd_pcm_format_set_silence".[1] It is due to missing validation of the "silence" field of struct "pcm_format_data" in "pcm_formats" array. Add a test for valid "pat" and, if it is not so, return -EINVAL. [1] https://lore.kernel.org/lkml/000000000000d188ef05dc2c7279@google.com/ Reported-and-tested-by: syzbot+205eb15961852c2c5974@syzkaller.appspotmail.com Signed-off-by: Fabio M. De Francesco Cc: Link: https://lore.kernel.org/r/20220409012655.9399-1-fmdefrancesco@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/core/pcm_misc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/sound/core/pcm_misc.c +++ b/sound/core/pcm_misc.c @@ -412,7 +412,7 @@ int snd_pcm_format_set_silence(snd_pcm_f return 0; width = pcm_formats[(INT)format].phys; /* physical width */ pat = pcm_formats[(INT)format].silence; - if (! width) + if (!width || !pat) return -EINVAL; /* signed or 1 byte data */ if (pcm_formats[(INT)format].signd == 1 || width <= 8) {