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=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 F0B3FC282CE for ; Tue, 4 Jun 2019 23:22:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C0CF220862 for ; Tue, 4 Jun 2019 23:22:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559690546; bh=Imy2Xfwwpn+5OIUkIvfTfUuzhktvygkHS8+PLdzSwQE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=qCiqf178Tud1TapViVgjkrmAX14fwx3umGlvgWRuUXSY1x8vuNaXV0TXgbnzo8WiL Sc+Ey3zhyPDivnG2nPVUFXOb8EzCrQCxkHYpbsCzjtBYOS2gSdsxKHIULWyuBg3wPu ZIrtNhF5wBbC7mL4OAZv/zTkHhQ7D56KeWNkJDf4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726708AbfFDXW0 (ORCPT ); Tue, 4 Jun 2019 19:22:26 -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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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