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 53162C2BA83 for ; Fri, 14 Feb 2020 17:15:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2CC84222C2 for ; Fri, 14 Feb 2020 17:15:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581700557; bh=Kg5IVRnEpP2SMZz+UVMqxwQ0BK2QI7KyO+6LMZWsYPg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ZH0VMq3TJVi0jIV4PLqmKqL9UsE3dbrI/YNHG1L9Wbuf+/iJDSqdIFUCh0jLqKQWA 8F/uo4gKg6jQpexsl+Z7shtC4oHvqm6afSWGIEFlAYy3mmZdCJIi3zf8TCSUlWJUP1 ioM8azkEhvfzIpjPjPzz3AaB64FoY5tByvoeXc3c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391565AbgBNQMD (ORCPT ); Fri, 14 Feb 2020 11:12:03 -0500 Received: from mail.kernel.org ([198.145.29.99]:39214 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391913AbgBNQMD (ORCPT ); Fri, 14 Feb 2020 11:12:03 -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 5A07B246A4; Fri, 14 Feb 2020 16:12:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581696723; bh=Kg5IVRnEpP2SMZz+UVMqxwQ0BK2QI7KyO+6LMZWsYPg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g9JdIMJ0RVAyi7YobJzlbm7ps7RngpgYYFkAasqkNmZjQ9hRr1gYl1LI6cVBZsOWA okBk/Rsm691wpEUom/4m9QxjJ/73eOeFGBEblIRMIL7Jjb+1JTWe3SG3Ogzxhrx5Wy aKcrM1WWIVx2lf8xzjEbSKbFFqdZm8HuIz8Iil8o= 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 4.19 011/252] ALSA: ctl: allow TLV read operation for callback type of element in locked case Date: Fri, 14 Feb 2020 11:07:46 -0500 Message-Id: <20200214161147.15842-11-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214161147.15842-1-sashal@kernel.org> References: <20200214161147.15842-1-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 649d3217590ed..d1312f14d78fb 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -1468,8 +1468,9 @@ 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