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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 271EBC3B1B5 for ; Fri, 14 Feb 2020 18:21:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F09F6222C2 for ; Fri, 14 Feb 2020 18:21:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581704499; bh=CqYiNBMlMWHKkp/lCav82O14317gOiqR2e73IbrS+zI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=hCQoXwivmANixQF/uH7IWo8wGpqiEvQfBkvtDdWeW5kdqThTPrE5OJB58MrHgqxlc epSZxM4X3F5/gFFDgj4gRPWlBqCpwHqc5UTp6VMrokibpexbbQnUGTKsLRbjtw4GC8 KLtrvOtecGQJZuFM4S0zNH3wduB1jtyHoBgd0pOs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730123AbgBNPtm (ORCPT ); Fri, 14 Feb 2020 10:49:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:52694 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730060AbgBNPti (ORCPT ); Fri, 14 Feb 2020 10:49:38 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F018A24654; Fri, 14 Feb 2020 15:49:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581695377; bh=CqYiNBMlMWHKkp/lCav82O14317gOiqR2e73IbrS+zI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y9yjBnN3Cc3qspPMg5aXvaIoMyk+Be8a0Vqyaj8jpw6j1KVGJEh87/wmYdLpSfIw3 0gCzp8i6T5HwWSAaj1VqQ9c6nvzv0J3vqolBwD7y9J+OLmEqhMHvDhtrUTPYPEZ64o 47CXTMKrc8Qjzm4mdwNVHPK6Oc8+Ud3MYJLqJsvM= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Takashi Sakamoto , Jaroslav Kysela , Takashi Iwai , Sasha Levin , alsa-devel@alsa-project.org Subject: [PATCH AUTOSEL 5.5 033/542] ALSA: ctl: allow TLV read operation for callback type of element in locked case Date: Fri, 14 Feb 2020 10:40:25 -0500 Message-Id: <20200214154854.6746-33-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214154854.6746-1-sashal@kernel.org> References: <20200214154854.6746-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Takashi Sakamoto [ Upstream commit d61fe22c2ae42d9fd76c34ef4224064cca4b04b0 ] A design of ALSA control core allows applications to execute three operations for TLV feature; read, write and command. Furthermore, it allows driver developers to process the operations by two ways; allocated array or callback function. In the former, read operation is just allowed, thus developers uses the latter when device driver supports variety of models or the target model is expected to dynamically change information stored in TLV container. The core also allows applications to lock any element so that the other applications can't perform write operation to the element for element value and TLV information. When the element is locked, write and command operation for TLV information are prohibited as well as element value. Any read operation should be allowed in the case. At present, when an element has callback function for TLV information, TLV read operation returns EPERM if the element is locked. On the other hand, the read operation is success when an element has allocated array for TLV information. In both cases, read operation is success for element value expectedly. This commit fixes the bug. This change can be backported to v4.14 kernel or later. Signed-off-by: Takashi Sakamoto Reviewed-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20191223093347.15279-1-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/core/control.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/sound/core/control.c b/sound/core/control.c index 7a4d8690ce41f..08ca7666e84cf 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1430,8 +1430,9 @@ static int call_tlv_handler(struct snd_ctl_file *file, int op_flag, if (kctl->tlv.c == NULL) return -ENXIO; - /* When locked, this is unavailable. */ - if (vd->owner != NULL && vd->owner != file) + /* Write and command operations are not allowed for locked element. */ + if (op_flag != SNDRV_CTL_TLV_OP_READ && + vd->owner != NULL && vd->owner != file) return -EPERM; return kctl->tlv.c(kctl, op_flag, size, buf); -- 2.20.1