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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 E91ADC35642 for ; Fri, 21 Feb 2020 08:49:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C20E820722 for ; Fri, 21 Feb 2020 08:49:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582274982; bh=CqYiNBMlMWHKkp/lCav82O14317gOiqR2e73IbrS+zI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0QZW+hge7Fx8W1fq+INW/AYPRPM7fEmLU9VagpU4ovH54c2fto/9s9Cee2Ge5CdhR H7hphDCHs3EEUn0tAKkj3CrV1uN77NI1hDpScA64AUMZ+oZUTUv1EuQecgmPCH+YF0 5eb1jNe5kHJp1f9tVbRbwjaGiHbNvaqiuByE6Cig= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727107AbgBUHpB (ORCPT ); Fri, 21 Feb 2020 02:45:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:39990 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728208AbgBUHpB (ORCPT ); Fri, 21 Feb 2020 02:45:01 -0500 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 DE448222C4; Fri, 21 Feb 2020 07:44:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582271100; bh=CqYiNBMlMWHKkp/lCav82O14317gOiqR2e73IbrS+zI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q5qnbLbsXZrQSl3BDKtpj9wK3vkWvDP5EDAGG+2gT605+chwOlSBkxCY8hz+VuYjz XDQn7K09j3Sh4ob+ja4DeA3kk8roN7vPxIQER1Z5mNZ+VW+Djd81xNepw2KZlRT7sw ayZklIBm3YvJMVBVt0MT9606dEvqX+VD/1Nb1ewo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Takashi Sakamoto , Jaroslav Kysela , Takashi Iwai , Sasha Levin Subject: [PATCH 5.5 032/399] ALSA: ctl: allow TLV read operation for callback type of element in locked case Date: Fri, 21 Feb 2020 08:35:57 +0100 Message-Id: <20200221072405.496012264@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200221072402.315346745@linuxfoundation.org> References: <20200221072402.315346745@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 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