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=ham 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 E3BF4C35640 for ; Fri, 21 Feb 2020 08:02:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B8481206ED for ; Fri, 21 Feb 2020 08:02:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272137; bh=CqYiNBMlMWHKkp/lCav82O14317gOiqR2e73IbrS+zI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Oqx7lr6d+Vu16Sdb/Pi4lSyMPsNNPlBBfXFtcTcstio9UJ9obG08ewF+nkaCX3c5X 5e+29TCmOLTYsk6I55mKyT2soyKYkYiBnNKK319xPRPCI7JembJGdy54L9TNzOCUwk b2xB+lU8pn7xBRTnRVQOmcQsr9RR1FAZB5kMaKl0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731102AbgBUICQ (ORCPT ); Fri, 21 Feb 2020 03:02:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:34612 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731312AbgBUICK (ORCPT ); Fri, 21 Feb 2020 03:02:10 -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 E91772073A; Fri, 21 Feb 2020 08:02:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582272130; bh=CqYiNBMlMWHKkp/lCav82O14317gOiqR2e73IbrS+zI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hMvXp/MQ56wr9rMQ6/mn9FE8GqbCsdPEAZh8wAVGuD6DHaR/zoUTHSSCeIFSUwycT vKG6FY+DAvAXh8dnTZh7YFCdd3XuKRGF6qjTwYTMTHRPdkkkK+s5bKfSkb1qGC8A0s lNtlHPO7e38HUhJs2aFVmkFI7BCqNGlYFvhihc7A= 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 5.4 027/344] ALSA: ctl: allow TLV read operation for callback type of element in locked case Date: Fri, 21 Feb 2020 08:37:06 +0100 Message-Id: <20200221072351.630672854@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200221072349.335551332@linuxfoundation.org> References: <20200221072349.335551332@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