From patchwork Thu Jan 23 16:46:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 11349021 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2249592A for ; Thu, 23 Jan 2020 18:53:18 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E8C7821569 for ; Thu, 23 Jan 2020 18:53:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="LPq6Xjrw" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E8C7821569 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:35130 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iuhbQ-000207-Ib for patchwork-qemu-devel@patchwork.kernel.org; Thu, 23 Jan 2020 13:53:16 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:42286) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iufed-0005nb-EL for qemu-devel@nongnu.org; Thu, 23 Jan 2020 11:48:28 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iufec-0007pF-0a for qemu-devel@nongnu.org; Thu, 23 Jan 2020 11:48:27 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:43362 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iufeb-0007oW-Ti for qemu-devel@nongnu.org; Thu, 23 Jan 2020 11:48:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579798105; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xr5sJDBg9ZhH2lRGDj6MS3ljeG8AkiArnkJCqI0i0Aw=; b=LPq6XjrwY5907W719wqDR2erVCa9gA4r/BVAqvFE4JfHg0wN7DR1wxszB1WJgXz3iJxwBe qZMtk5FdpTPEok/4xKa2jSLTQjp+g+8eOrcn9keytv2JmHsn44h1HFh3vhiDxrFMRq4VNZ h822G0rZ3Y9Kb2QQVSl3PrlBSwR8uzE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-336-Ggtk970DPNKkNWsphsc0zA-1; Thu, 23 Jan 2020 11:48:23 -0500 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D8B3010883AD for ; Thu, 23 Jan 2020 16:48:22 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-116-110.ams2.redhat.com [10.36.116.110]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3005C2899A; Thu, 23 Jan 2020 16:48:22 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com Subject: [PULL 081/108] virtiofsd: Prevent multiply running with same vhost_user_socket Date: Thu, 23 Jan 2020 16:46:03 +0000 Message-Id: <20200123164630.91498-82-dgilbert@redhat.com> In-Reply-To: <20200123164630.91498-1-dgilbert@redhat.com> References: <20200123164630.91498-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: Ggtk970DPNKkNWsphsc0zA-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 205.139.110.61 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Masayoshi Mizuma virtiofsd can run multiply even if the vhost_user_socket is same path. ]# ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu -o source=/tmp/share & [1] 244965 virtio_session_mount: Waiting for vhost-user socket connection... ]# ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu -o source=/tmp/share & [2] 244966 virtio_session_mount: Waiting for vhost-user socket connection... ]# The user will get confused about the situation and maybe the cause of the unexpected problem. So it's better to prevent the multiple running. Create a regular file under localstatedir directory to exclude the vhost_user_socket. To create and lock the file, use qemu_write_pidfile() because the API has some sanity checks and file lock. Signed-off-by: Masayoshi Mizuma Signed-off-by: Dr. David Alan Gilbert Applied fixes from Stefan's review and moved osdep include Signed-off-by: Stefan Hajnoczi Reviewed-by: Daniel P. Berrangé Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/fuse_lowlevel.c | 1 + tools/virtiofsd/fuse_virtio.c | 49 ++++++++++++++++++++++++++++++++- 2 files changed, 49 insertions(+), 1 deletion(-) diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c index 440508a6ec..aac282f278 100644 --- a/tools/virtiofsd/fuse_lowlevel.c +++ b/tools/virtiofsd/fuse_lowlevel.c @@ -18,6 +18,7 @@ #include #include +#include #include #include #include diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c index e7bd772805..b7948def27 100644 --- a/tools/virtiofsd/fuse_virtio.c +++ b/tools/virtiofsd/fuse_virtio.c @@ -13,11 +13,12 @@ #include "qemu/osdep.h" #include "qemu/iov.h" -#include "fuse_virtio.h" +#include "qapi/error.h" #include "fuse_i.h" #include "standard-headers/linux/fuse.h" #include "fuse_misc.h" #include "fuse_opt.h" +#include "fuse_virtio.h" #include #include @@ -743,6 +744,42 @@ int virtio_loop(struct fuse_session *se) return 0; } +static void strreplace(char *s, char old, char new) +{ + for (; *s; ++s) { + if (*s == old) { + *s = new; + } + } +} + +static bool fv_socket_lock(struct fuse_session *se) +{ + g_autofree gchar *sk_name = NULL; + g_autofree gchar *pidfile = NULL; + g_autofree gchar *dir = NULL; + Error *local_err = NULL; + + dir = qemu_get_local_state_pathname("run/virtiofsd"); + + if (g_mkdir_with_parents(dir, S_IRWXU) < 0) { + fuse_log(FUSE_LOG_ERR, "%s: Failed to create directory %s: %s", + __func__, dir, strerror(errno)); + return false; + } + + sk_name = g_strdup(se->vu_socket_path); + strreplace(sk_name, '/', '.'); + pidfile = g_strdup_printf("%s/%s.pid", dir, sk_name); + + if (!qemu_write_pidfile(pidfile, &local_err)) { + error_report_err(local_err); + return false; + } + + return true; +} + static int fv_create_listen_socket(struct fuse_session *se) { struct sockaddr_un un; @@ -758,6 +795,16 @@ static int fv_create_listen_socket(struct fuse_session *se) return -1; } + if (!strlen(se->vu_socket_path)) { + fuse_log(FUSE_LOG_ERR, "Socket path is empty\n"); + return -1; + } + + /* Check the vu_socket_path is already used */ + if (!fv_socket_lock(se)) { + return -1; + } + /* * Create the Unix socket to communicate with qemu * based on QEMU's vhost-user-bridge