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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,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 2D09AC28CC6 for ; Tue, 4 Jun 2019 23:33:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F04C8206C1 for ; Tue, 4 Jun 2019 23:33:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559691204; bh=Imy2Xfwwpn+5OIUkIvfTfUuzhktvygkHS8+PLdzSwQE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=RvxQ8UFy4DxrnXQQWY8c48YWiTLA4nhd2VuGHtCUg5137EtX9sfjohTZK2ZITkilF aNNTveD+UCYk4ffdn54uqKTZnAViLA4gr+v2IyrTiifIK4RkqwKiQZe2IlUwHq0t6K k8VvddiCpXvDqgru9dHY5VWZa7lLaTbg9k3HTzhU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726682AbfFDXWY (ORCPT ); Tue, 4 Jun 2019 19:22:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:60604 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726663AbfFDXWY (ORCPT ); Tue, 4 Jun 2019 19:22:24 -0400 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 084D12085A; Tue, 4 Jun 2019 23:22:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559690543; bh=Imy2Xfwwpn+5OIUkIvfTfUuzhktvygkHS8+PLdzSwQE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=S2QMIvSwEGl7RFCpAbQtZN88N644FfUdkTHs4f+0eR1rnzPSb2rVZDCfT2X2OqCNg y1+OOt9Mykl3x2ea61KEqCpTFem/j6BvmXcedNtCo/1fe2Rp2EYTt63CIOqXcomoSM /Xx/G2o54d9+AoNbq5122PRiaXc0pZerNaAuYZpg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Takashi Iwai , syzbot+47ded6c0f23016cde310@syzkaller.appspotmail.com, Sasha Levin Subject: [PATCH AUTOSEL 5.1 04/60] Revert "ALSA: seq: Protect in-kernel ioctl calls with mutex" Date: Tue, 4 Jun 2019 19:21:14 -0400 Message-Id: <20190604232212.6753-4-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190604232212.6753-1-sashal@kernel.org> References: <20190604232212.6753-1-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 Iwai [ Upstream commit f0654ba94e33699b295ce4f3dc73094db6209035 ] This reverts commit feb689025fbb6f0aa6297d3ddf97de945ea4ad32. The fix attempt was incorrect, leading to the mutex deadlock through the close of OSS sequencer client. The proper fix needs more consideration, so let's revert it now. Fixes: feb689025fbb ("ALSA: seq: Protect in-kernel ioctl calls with mutex") Reported-by: syzbot+47ded6c0f23016cde310@syzkaller.appspotmail.com Signed-off-by: Takashi Iwai Signed-off-by: Sasha Levin --- sound/core/seq/seq_clientmgr.c | 9 ++------- 1 file changed, 2 insertions(+), 7 deletions(-) diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c index 8599f2937ac1..c99e1b77a45b 100644 --- a/sound/core/seq/seq_clientmgr.c +++ b/sound/core/seq/seq_clientmgr.c @@ -2337,19 +2337,14 @@ int snd_seq_kernel_client_ctl(int clientid, unsigned int cmd, void *arg) { const struct ioctl_handler *handler; struct snd_seq_client *client; - int err; client = clientptr(clientid); if (client == NULL) return -ENXIO; for (handler = ioctl_handlers; handler->cmd > 0; ++handler) { - if (handler->cmd == cmd) { - mutex_lock(&client->ioctl_mutex); - err = handler->func(client, arg); - mutex_unlock(&client->ioctl_mutex); - return err; - } + if (handler->cmd == cmd) + return handler->func(client, arg); } pr_debug("ALSA: seq unknown ioctl() 0x%x (type='%c', number=0x%02x)\n", -- 2.20.1