From patchwork Thu Oct 24 11:26:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 1182945 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="jGC4qO3Q"; 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 46zQR81CBYz9sQv for ; Thu, 24 Oct 2019 22:45:24 +1100 (AEDT) Received: from localhost ([::1]:40232 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNbYP-0005IE-MH for incoming@patchwork.ozlabs.org; Thu, 24 Oct 2019 07:45:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39252) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNbHR-00028h-G1 for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:27:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNbHP-0008Lh-O0 for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:27:49 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:42422 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 1iNbHP-0008LT-Jv for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:27:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571916467; 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=epYFexBAvojJruBQufHQ3wH4UK2rDrrqSsjxLR4oqMI=; b=jGC4qO3QM9S12lNtsOVfm+aUOwwBgcJ2fk5Reewm+xFWCyO186is6145jio1TAI1eYvPyw TjaBwxI2glGCJdJWt9tesY8A1I2xo2zXFBOJ/PJ31rVo409r0GwqP0OiWUCHrU+6Kcg4NN 9G7iQhQBnWyCsgOdH3my/pqgc404klU= 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-78-Gc9NGrtTOcaMrzlHZizrbA-1; Thu, 24 Oct 2019 07:27:37 -0400 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 0DB3A800D49; Thu, 24 Oct 2019 11:27:36 +0000 (UTC) Received: from dgilbert-t580.localhost (ovpn-117-248.ams2.redhat.com [10.36.117.248]) by smtp.corp.redhat.com (Postfix) with ESMTP id 899C11C93D; Thu, 24 Oct 2019 11:27:33 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, renzhen@linux.alibaba.com, eguan@linux.alibaba.com, ganesh.mahalingam@intel.com, m.mizuma@jp.fujitsu.com, mszeredi@redhat.com, misono.tomohiro@jp.fujitsu.com, tao.peng@linux.alibaba.com, piaojun@huawei.com, stefanha@redhat.com, vgoyal@redhat.com, mst@redhat.com, berrange@redhat.com Subject: [PATCH 03/25] virtiofsd: passthrough_ll: add ino_map to hide lo_inode pointers Date: Thu, 24 Oct 2019 12:26:56 +0100 Message-Id: <20191024112718.34657-4-dgilbert@redhat.com> In-Reply-To: <20191024112718.34657-1-dgilbert@redhat.com> References: <20191024112718.34657-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-MC-Unique: Gc9NGrtTOcaMrzlHZizrbA-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: 205.139.110.120 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 Do not expose lo_inode pointers to clients. Signed-off-by: Stefan Hajnoczi --- contrib/virtiofsd/passthrough_ll.c | 125 ++++++++++++++++++++++++----- 1 file changed, 105 insertions(+), 20 deletions(-) diff --git a/contrib/virtiofsd/passthrough_ll.c b/contrib/virtiofsd/passthrough_ll.c index 3093d1171e..f718c951f7 100644 --- a/contrib/virtiofsd/passthrough_ll.c +++ b/contrib/virtiofsd/passthrough_ll.c @@ -56,8 +56,8 @@ #define HAVE_POSIX_FALLOCATE 1 -/* We are re-using pointers to our `struct lo_inode` and `struct - lo_dirp` elements as inodes. This means that we must be able to +/* We are re-using pointers to our `struct lo_dirp` + elements as inodes. This means that we must be able to store uintptr_t values in a fuse_ino_t variable. The following incantation checks this condition at compile time. */ #if defined(__GNUC__) && (__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 6) && !defined __cplusplus @@ -71,7 +71,7 @@ struct _uintptr_to_must_hold_fuse_ino_t_dummy_struct \ struct lo_map_elem { union { - /* Element values will go here... */ + struct lo_inode *inode; ssize_t freelist; }; bool in_use; @@ -92,6 +92,7 @@ struct lo_inode { ino_t ino; dev_t dev; uint64_t refcount; /* protected by lo->mutex */ + fuse_ino_t fuse_ino; }; struct lo_cred { @@ -116,6 +117,7 @@ struct lo_data { int cache; int timeout_set; struct lo_inode root; /* protected by lo->mutex */ + struct lo_map ino_map; /* protected by lo->mutex */ }; static const struct fuse_opt lo_opts[] = { @@ -250,17 +252,38 @@ static void lo_map_remove(struct lo_map *map, size_t key) map->freelist = key; } +/* Assumes lo->mutex is held */ +static ssize_t lo_add_inode_mapping(fuse_req_t req, struct lo_inode *inode) +{ + struct lo_map_elem *elem; + + elem = lo_map_alloc_elem(&lo_data(req)->ino_map); + if (!elem) + return -1; + + elem->inode = inode; + return elem - lo_data(req)->ino_map.elems; +} + static struct lo_inode *lo_inode(fuse_req_t req, fuse_ino_t ino) { - if (ino == FUSE_ROOT_ID) - return &lo_data(req)->root; - else - return (struct lo_inode *) (uintptr_t) ino; + struct lo_data *lo = lo_data(req); + struct lo_map_elem *elem; + + pthread_mutex_lock(&lo->mutex); + elem = lo_map_get(&lo->ino_map, ino); + pthread_mutex_unlock(&lo->mutex); + + if (!elem) + return NULL; + + return elem->inode; } static int lo_fd(fuse_req_t req, fuse_ino_t ino) { - return lo_inode(req, ino)->fd; + struct lo_inode *inode = lo_inode(req, ino); + return inode ? inode->fd : -1; } static bool lo_debug(fuse_req_t req) @@ -330,10 +353,18 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, { int saverr; char procname[64]; - struct lo_inode *inode = lo_inode(req, ino); - int ifd = inode->fd; + struct lo_inode *inode; + int ifd; int res; + inode = lo_inode(req, ino); + if (!inode) { + fuse_reply_err(req, EBADF); + return; + } + + ifd = inode->fd; + if (valid & FUSE_SET_ATTR_MODE) { if (fi) { res = fchmod(fi->fh, attr->st_mode); @@ -456,6 +487,7 @@ static int lo_do_lookup(fuse_req_t req, fuse_ino_t parent, const char *name, inode->dev = e->attr.st_dev; pthread_mutex_lock(&lo->mutex); + inode->fuse_ino = lo_add_inode_mapping(req, inode); prev = &lo->root; next = prev->next; next->prev = inode; @@ -464,7 +496,7 @@ static int lo_do_lookup(fuse_req_t req, fuse_ino_t parent, const char *name, prev->next = inode; pthread_mutex_unlock(&lo->mutex); } - e->ino = (uintptr_t) inode; + e->ino = inode->fuse_ino; if (lo_debug(req)) fuse_log(FUSE_LOG_DEBUG, " %lli/%s -> %lli\n", @@ -546,10 +578,16 @@ static void lo_mknod_symlink(fuse_req_t req, fuse_ino_t parent, { int res; int saverr; - struct lo_inode *dir = lo_inode(req, parent); + struct lo_inode *dir; struct fuse_entry_param e; struct lo_cred old = {}; + dir = lo_inode(req, parent); + if (!dir) { + fuse_reply_err(req, EBADF); + return; + } + saverr = ENOMEM; saverr = lo_change_cred(req, &old); @@ -623,10 +661,16 @@ static void lo_link(fuse_req_t req, fuse_ino_t ino, fuse_ino_t parent, { int res; struct lo_data *lo = lo_data(req); - struct lo_inode *inode = lo_inode(req, ino); + struct lo_inode *inode; struct fuse_entry_param e; int saverr; + inode = lo_inode(req, ino); + if (!inode) { + fuse_reply_err(req, EBADF); + return; + } + memset(&e, 0, sizeof(struct fuse_entry_param)); e.attr_timeout = lo->timeout; e.entry_timeout = lo->timeout; @@ -642,7 +686,7 @@ static void lo_link(fuse_req_t req, fuse_ino_t ino, fuse_ino_t parent, pthread_mutex_lock(&lo->mutex); inode->refcount++; pthread_mutex_unlock(&lo->mutex); - e.ino = (uintptr_t) inode; + e.ino = inode->fuse_ino; if (lo_debug(req)) fuse_log(FUSE_LOG_DEBUG, " %lli/%s -> %lli\n", @@ -708,10 +752,10 @@ static void unref_inode(struct lo_data *lo, struct lo_inode *inode, uint64_t n) next->prev = prev; prev->next = next; + lo_map_remove(&lo->ino_map, inode->fuse_ino); pthread_mutex_unlock(&lo->mutex); close(inode->fd); free(inode); - } else { pthread_mutex_unlock(&lo->mutex); } @@ -720,7 +764,11 @@ static void unref_inode(struct lo_data *lo, struct lo_inode *inode, uint64_t n) static void lo_forget_one(fuse_req_t req, fuse_ino_t ino, uint64_t nlookup) { struct lo_data *lo = lo_data(req); - struct lo_inode *inode = lo_inode(req, ino); + struct lo_inode *inode; + + inode = lo_inode(req, ino); + if (!inode) + return; if (lo_debug(req)) { fuse_log(FUSE_LOG_DEBUG, " forget %lli %lli -%lli\n", @@ -1161,10 +1209,16 @@ static void lo_getxattr(fuse_req_t req, fuse_ino_t ino, const char *name, { char *value = NULL; char procname[64]; - struct lo_inode *inode = lo_inode(req, ino); + struct lo_inode *inode; ssize_t ret; int saverr; + inode = lo_inode(req, ino); + if (!inode) { + fuse_reply_err(req, EBADF); + return; + } + saverr = ENOSYS; if (!lo_data(req)->xattr) goto out; @@ -1217,10 +1271,16 @@ static void lo_listxattr(fuse_req_t req, fuse_ino_t ino, size_t size) { char *value = NULL; char procname[64]; - struct lo_inode *inode = lo_inode(req, ino); + struct lo_inode *inode; ssize_t ret; int saverr; + inode = lo_inode(req, ino); + if (!inode) { + fuse_reply_err(req, EBADF); + return; + } + saverr = ENOSYS; if (!lo_data(req)->xattr) goto out; @@ -1273,10 +1333,16 @@ static void lo_setxattr(fuse_req_t req, fuse_ino_t ino, const char *name, const char *value, size_t size, int flags) { char procname[64]; - struct lo_inode *inode = lo_inode(req, ino); + struct lo_inode *inode; ssize_t ret; int saverr; + inode = lo_inode(req, ino); + if (!inode) { + fuse_reply_err(req, EBADF); + return; + } + saverr = ENOSYS; if (!lo_data(req)->xattr) goto out; @@ -1304,10 +1370,16 @@ out: static void lo_removexattr(fuse_req_t req, fuse_ino_t ino, const char *name) { char procname[64]; - struct lo_inode *inode = lo_inode(req, ino); + struct lo_inode *inode; ssize_t ret; int saverr; + inode = lo_inode(req, ino); + if (!inode) { + fuse_reply_err(req, EBADF); + return; + } + saverr = ENOSYS; if (!lo_data(req)->xattr) goto out; @@ -1411,6 +1483,7 @@ int main(int argc, char *argv[]) struct fuse_cmdline_opts opts; struct lo_data lo = { .debug = 0, .writeback = 0 }; + struct lo_map_elem *root_elem; int ret = -1; /* Don't mask creation mode, kernel already did that */ @@ -1419,8 +1492,18 @@ int main(int argc, char *argv[]) pthread_mutex_init(&lo.mutex, NULL); lo.root.next = lo.root.prev = &lo.root; lo.root.fd = -1; + lo.root.fuse_ino = FUSE_ROOT_ID; lo.cache = CACHE_NORMAL; + /* Set up the ino map like this: + * [0] Reserved (will not be used) + * [1] Root inode + */ + lo_map_init(&lo.ino_map); + lo_map_reserve(&lo.ino_map, 0)->in_use = false; + root_elem = lo_map_reserve(&lo.ino_map, lo.root.fuse_ino); + root_elem->inode = &lo.root; + if (fuse_parse_cmdline(&args, &opts) != 0) return 1; if (opts.show_help) { @@ -1514,6 +1597,8 @@ err_out2: err_out1: fuse_opt_free_args(&args); + lo_map_destroy(&lo.ino_map); + if (lo.root.fd >= 0) close(lo.root.fd);