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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 36A0EC10F27 for ; Tue, 10 Mar 2020 12:47:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0B62B2468E for ; Tue, 10 Mar 2020 12:47:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583844475; bh=g9FrH39E2EWG7NdRwYJpo7nD4uRn8g79O8Prpmhhhqk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ous8LLRxEL2G2sOZ3FysUOpyvyRTqCA1CKsrAabPVAuZOl+Z2p+ZziazdlaouVVRs HU8eDTWEQcu0U0T2BsDbaOWw6GVMN5STMAHYhGtDKp1TT67aMysVshbS9kQgSo5uo5 mxXB1zeVX6Jd2XzsKfv0khaKnrxnJMgr1v4BZv5M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728235AbgCJMrx (ORCPT ); Tue, 10 Mar 2020 08:47:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:51704 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727978AbgCJMrt (ORCPT ); Tue, 10 Mar 2020 08:47:49 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BE9692468F; Tue, 10 Mar 2020 12:47:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583844468; bh=g9FrH39E2EWG7NdRwYJpo7nD4uRn8g79O8Prpmhhhqk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mVElWaV/JFFm63Fk+8DDaWij2MIB6aE47g1YVy7KJ/72Iw6MAFZDM5mrHuYt7mAxf TO/aQi1rOgrWY9XM/xGB4R0XFHjraVqfGrS633sRIoCQIha4GXZL8MtLEvq8SEGVjS 3PCXH+MNQjttQ+byQbmyhiA5bnzC0oqdAnMAf4Ew= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Takashi Iwai , Cezary Rojewski , Mark Brown Subject: [PATCH 4.9 78/88] ASoC: pcm: Fix possible buffer overflow in dpcm state sysfs output Date: Tue, 10 Mar 2020 13:39:26 +0100 Message-Id: <20200310123624.267419035@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200310123606.543939933@linuxfoundation.org> References: <20200310123606.543939933@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Takashi Iwai commit 6c89ffea60aa3b2a33ae7987de1e84bfb89e4c9e upstream. dpcm_show_state() invokes multiple snprintf() calls to concatenate formatted strings on the fixed size buffer. The usage of snprintf() is supposed for avoiding the buffer overflow, but it doesn't work as expected because snprintf() doesn't return the actual output size but the size to be written. Fix this bug by replacing all snprintf() calls with scnprintf() calls. Fixes: f86dcef87b77 ("ASoC: dpcm: Add debugFS support for DPCM") Signed-off-by: Takashi Iwai Acked-by: Cezary Rojewski Link: https://lore.kernel.org/r/20200218111737.14193-4-tiwai@suse.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- sound/soc/soc-pcm.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) --- a/sound/soc/soc-pcm.c +++ b/sound/soc/soc-pcm.c @@ -2979,16 +2979,16 @@ static ssize_t dpcm_show_state(struct sn ssize_t offset = 0; /* FE state */ - offset += snprintf(buf + offset, size - offset, + offset += scnprintf(buf + offset, size - offset, "[%s - %s]\n", fe->dai_link->name, stream ? "Capture" : "Playback"); - offset += snprintf(buf + offset, size - offset, "State: %s\n", + offset += scnprintf(buf + offset, size - offset, "State: %s\n", dpcm_state_string(fe->dpcm[stream].state)); if ((fe->dpcm[stream].state >= SND_SOC_DPCM_STATE_HW_PARAMS) && (fe->dpcm[stream].state <= SND_SOC_DPCM_STATE_STOP)) - offset += snprintf(buf + offset, size - offset, + offset += scnprintf(buf + offset, size - offset, "Hardware Params: " "Format = %s, Channels = %d, Rate = %d\n", snd_pcm_format_name(params_format(params)), @@ -2996,10 +2996,10 @@ static ssize_t dpcm_show_state(struct sn params_rate(params)); /* BEs state */ - offset += snprintf(buf + offset, size - offset, "Backends:\n"); + offset += scnprintf(buf + offset, size - offset, "Backends:\n"); if (list_empty(&fe->dpcm[stream].be_clients)) { - offset += snprintf(buf + offset, size - offset, + offset += scnprintf(buf + offset, size - offset, " No active DSP links\n"); goto out; } @@ -3008,16 +3008,16 @@ static ssize_t dpcm_show_state(struct sn struct snd_soc_pcm_runtime *be = dpcm->be; params = &dpcm->hw_params; - offset += snprintf(buf + offset, size - offset, + offset += scnprintf(buf + offset, size - offset, "- %s\n", be->dai_link->name); - offset += snprintf(buf + offset, size - offset, + offset += scnprintf(buf + offset, size - offset, " State: %s\n", dpcm_state_string(be->dpcm[stream].state)); if ((be->dpcm[stream].state >= SND_SOC_DPCM_STATE_HW_PARAMS) && (be->dpcm[stream].state <= SND_SOC_DPCM_STATE_STOP)) - offset += snprintf(buf + offset, size - offset, + offset += scnprintf(buf + offset, size - offset, " Hardware Params: " "Format = %s, Channels = %d, Rate = %d\n", snd_pcm_format_name(params_format(params)),