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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 0845DC433FF for ; Thu, 1 Aug 2019 17:03:59 +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 CCA3B20B7C for ; Thu, 1 Aug 2019 17:03:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CCA3B20B7C 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+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57826 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1htEUc-0004vh-3e for qemu-devel@archiver.kernel.org; Thu, 01 Aug 2019 13:03:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35227) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1htEQh-0002Dq-Rc for qemu-devel@nongnu.org; Thu, 01 Aug 2019 12:59:52 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1htEQg-0000Cz-Qn for qemu-devel@nongnu.org; Thu, 01 Aug 2019 12:59:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58430) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1htELl-0005T7-U9 for qemu-devel@nongnu.org; Thu, 01 Aug 2019 12:54:48 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 256613149676; Thu, 1 Aug 2019 16:54:36 +0000 (UTC) Received: from localhost (ovpn-116-232.ams2.redhat.com [10.36.116.232]) by smtp.corp.redhat.com (Postfix) with ESMTP id 67D0B608C2; Thu, 1 Aug 2019 16:54:31 +0000 (UTC) From: Stefan Hajnoczi To: virtio-fs@redhat.com, qemu-devel@nongnu.org Date: Thu, 1 Aug 2019 17:54:08 +0100 Message-Id: <20190801165409.20121-4-stefanha@redhat.com> In-Reply-To: <20190801165409.20121-1-stefanha@redhat.com> References: <20190801165409.20121-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.49]); Thu, 01 Aug 2019 16:54:36 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 3/4] virtiofsd: fix lo_destroy() resource leaks 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: , Cc: Liu Bo , "Dr. David Alan Gilbert" , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Now that lo_destroy() is serialized we can call unref_inode() so that all inode resources are freed. Signed-off-by: Stefan Hajnoczi --- contrib/virtiofsd/passthrough_ll.c | 43 ++++++++++++++---------------- 1 file changed, 20 insertions(+), 23 deletions(-) diff --git a/contrib/virtiofsd/passthrough_ll.c b/contrib/virtiofsd/passt= hrough_ll.c index a81c01d0d1..02a5e97326 100644 --- a/contrib/virtiofsd/passthrough_ll.c +++ b/contrib/virtiofsd/passthrough_ll.c @@ -1340,28 +1340,6 @@ static void unref_inode(struct lo_data *lo, struct= lo_inode *inode, uint64_t n) } } =20 -static int unref_all_inodes_cb(gpointer key, gpointer value, - gpointer user_data) -{ - struct lo_inode *inode =3D value; - struct lo_data *lo =3D user_data; - - inode->nlookup =3D 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 nlook= up) { struct lo_data *lo =3D lo_data(req); @@ -2462,6 +2440,18 @@ static void lo_removemapping(fuse_req_t req, struc= t fuse_session *se, fuse_reply_err(req, ret); } =20 +static int destroy_inode_cb(gpointer key, gpointer value, gpointer user_= data) +{ + struct lo_inode *inode =3D value; + struct lo_data *lo =3D user_data; + + /* inode->nlookup is normally protected by lo->mutex but see the + * comment in lo_destroy(). + */ + unref_inode(lo, inode, inode->nlookup); + return TRUE; +} + static void lo_destroy(void *userdata, struct fuse_session *se) { struct lo_data *lo =3D (struct lo_data*) userdata; @@ -2475,7 +2465,14 @@ static void lo_destroy(void *userdata, struct fuse= _session *se) fuse_err("%s: unmap during destroy failed\n", __= func__); } } - unref_all_inodes(lo); + + /* Normally lo->mutex must be taken when traversing lo->inodes b= ut + * lo_destroy() is a serialized request so no races are possible= here. + * + * In addition, we cannot acquire lo->mutex since destroy_inode_= cb() takes it + * too and this would result in a recursive lock. + */ + g_hash_table_foreach_remove(lo->inodes, destroy_inode_cb, lo); } =20 static struct fuse_lowlevel_ops lo_oper =3D { --=20 2.21.0