From patchwork Thu Dec 12 16:39:02 2019 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: 1208734 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.b="UKJkDTZA"; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 47YhMl5cLrz9sPT for ; Fri, 13 Dec 2019 04:57:23 +1100 (AEDT) Received: from localhost ([::1]:35096 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifSiH-0000OI-7q for incoming@patchwork.ozlabs.org; Thu, 12 Dec 2019 12:57:21 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:39060) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ifRXC-00082F-C8 for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:41:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ifRXB-00059j-3V for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:41:50 -0500 Received: from us-smtp-2.mimecast.com ([205.139.110.61]:53565 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ifRXA-00058x-V5 for qemu-devel@nongnu.org; Thu, 12 Dec 2019 11:41:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1576168908; 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=aFXzRnUUfN49Blvfmm9LqBuOUa1ZI4A1nWCoxa8Wcjs=; b=UKJkDTZA7MuD7D5Paf0Tb+xaHJ0sXstX4MVYR1Zo7iPZ61udEdXh0zcyqGHr/3KmUwbol7 dYvicjCr34wxdoGMGzCymPnT6q5VluW7RG6PuTy2qJfoYE6cH2Qwzi7BJ+6kmZs04G4fM5 Bej3AfciizgvS01KARCzVNMAywvB/s4= 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-8-7FKnJ5RHOTCq64rgankW6A-1; Thu, 12 Dec 2019 11:41:47 -0500 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 52BFD107ACCC for ; Thu, 12 Dec 2019 16:41:46 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-116-226.ams2.redhat.com [10.36.116.226]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7A04460BE1; Thu, 12 Dec 2019 16:41:45 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com, vgoyal@redhat.com Subject: [PATCH 102/104] virtiofsd: fix lo_destroy() resource leaks Date: Thu, 12 Dec 2019 16:39:02 +0000 Message-Id: <20191212163904.159893-103-dgilbert@redhat.com> In-Reply-To: <20191212163904.159893-1-dgilbert@redhat.com> References: <20191212163904.159893-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-MC-Unique: 7FKnJ5RHOTCq64rgankW6A-1 X-Mimecast-Spam-Score: 0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Stefan Hajnoczi Now that lo_destroy() is serialized we can call unref_inode() so that all inode resources are freed. Signed-off-by: Stefan Hajnoczi Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Philippe Mathieu-Daudé --- tools/virtiofsd/passthrough_ll.c | 41 ++++++++++++++++---------------- 1 file changed, 20 insertions(+), 21 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 1bf251a91d..38f4948e61 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -1355,26 +1355,6 @@ static void unref_inode_lolocked(struct lo_data *lo, struct lo_inode *inode, } } -static int unref_all_inodes_cb(gpointer key, gpointer value, gpointer user_data) -{ - struct lo_inode *inode = value; - struct lo_data *lo = user_data; - - inode->nlookup = 0; - lo_map_remove(&lo->ino_map, inode->fuse_ino); - close(inode->fd); - lo_inode_put(lo, &inode); /* Drop our refcount from lo_do_lookup() */ - - return TRUE; -} - -static void unref_all_inodes(struct lo_data *lo) -{ - pthread_mutex_lock(&lo->mutex); - g_hash_table_foreach_remove(lo->inodes, unref_all_inodes_cb, lo); - pthread_mutex_unlock(&lo->mutex); -} - static void lo_forget_one(fuse_req_t req, fuse_ino_t ino, uint64_t nlookup) { struct lo_data *lo = lo_data(req); @@ -2460,7 +2440,26 @@ static void lo_lseek(fuse_req_t req, fuse_ino_t ino, off_t off, int whence, static void lo_destroy(void *userdata) { struct lo_data *lo = (struct lo_data *)userdata; - unref_all_inodes(lo); + + /* + * Normally lo->mutex must be taken when traversing lo->inodes but + * lo_destroy() is a serialized request so no races are possible here. + * + * In addition, we cannot acquire lo->mutex since unref_inode() takes it + * too and this would result in a recursive lock. + */ + while (true) { + GHashTableIter iter; + gpointer key, value; + + g_hash_table_iter_init(&iter, lo->inodes); + if (!g_hash_table_iter_next(&iter, &key, &value)) { + break; + } + + struct lo_inode *inode = value; + unref_inode_lolocked(lo, inode, inode->nlookup); + } } static struct fuse_lowlevel_ops lo_oper = {