From patchwork Thu Jan 23 11:57:27 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: 1227909 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.a=rsa-sha256 header.s=mimecast20190719 header.b=g0J/jzy7; 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 483MyT4rgqz9sSR for ; Fri, 24 Jan 2020 00:08:01 +1100 (AEDT) Received: from localhost ([::1]:56766 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iucDH-0002fC-95 for incoming@patchwork.ozlabs.org; Thu, 23 Jan 2020 08:07:59 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:40549) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iub96-0002RD-Ad for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:37 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iub93-0005Ay-WE for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:35 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:27351 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 1iub93-0005Ao-Sc for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:33 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579780773; 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=kbq3LSVzyExiiVOzHu3bKtutkgWgmaw58V7faRhc0rA=; b=g0J/jzy7HZsaCUQoUG2mOkR7vDiogUfqY6To7av+ZSMrrGZZT6aU+wgUIwWDRJcOEp9IVi WbA2nVXCAc7I07vxUanNlZXbh40n2ZkFQ38dAorOODs7qZ7wubpwrNF+ivm+LaPQK234Yo /TzYHiWZixrzqNJw4o7CwhU+JloDqVI= 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-367-gdvGZBrcPtax7SjSTNT_-Q-1; Thu, 23 Jan 2020 06:59:32 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 58B581088380 for ; Thu, 23 Jan 2020 11:59:31 +0000 (UTC) Received: from dgilbert-t580.localhost (unknown [10.36.118.0]) by smtp.corp.redhat.com (Postfix) with ESMTP id A3EB41CB; Thu, 23 Jan 2020 11:59:30 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com Subject: [PULL 037/111] virtiofsd: passthrough_ll: add dirp_map to hide lo_dirp pointers Date: Thu, 23 Jan 2020 11:57:27 +0000 Message-Id: <20200123115841.138849-38-dgilbert@redhat.com> In-Reply-To: <20200123115841.138849-1-dgilbert@redhat.com> References: <20200123115841.138849-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: gdvGZBrcPtax7SjSTNT_-Q-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: 207.211.31.120 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_dirp pointers to clients. Signed-off-by: Stefan Hajnoczi Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 103 +++++++++++++++++++++++-------- 1 file changed, 76 insertions(+), 27 deletions(-) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index a3ebf74eab..5f5a72fdbb 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -56,27 +56,10 @@ #include "passthrough_helpers.h" -/* - * We are re-using pointers to our `struct lo_inode` - * 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 -_Static_assert(sizeof(fuse_ino_t) >= sizeof(uintptr_t), - "fuse_ino_t too small to hold uintptr_t values!"); -#else -struct _uintptr_to_must_hold_fuse_ino_t_dummy_struct { - unsigned _uintptr_to_must_hold_fuse_ino_t - : ((sizeof(fuse_ino_t) >= sizeof(uintptr_t)) ? 1 : -1); -}; -#endif - struct lo_map_elem { union { struct lo_inode *inode; + struct lo_dirp *dirp; ssize_t freelist; }; bool in_use; @@ -123,6 +106,7 @@ struct lo_data { int timeout_set; struct lo_inode root; /* protected by lo->mutex */ struct lo_map ino_map; /* protected by lo->mutex */ + struct lo_map dirp_map; /* protected by lo->mutex */ }; static const struct fuse_opt lo_opts[] = { @@ -252,6 +236,20 @@ 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_dirp_mapping(fuse_req_t req, struct lo_dirp *dirp) +{ + struct lo_map_elem *elem; + + elem = lo_map_alloc_elem(&lo_data(req)->dirp_map); + if (!elem) { + return -1; + } + + elem->dirp = dirp; + return elem - lo_data(req)->dirp_map.elems; +} + /* Assumes lo->mutex is held */ static ssize_t lo_add_inode_mapping(fuse_req_t req, struct lo_inode *inode) { @@ -861,9 +859,19 @@ struct lo_dirp { off_t offset; }; -static struct lo_dirp *lo_dirp(struct fuse_file_info *fi) +static struct lo_dirp *lo_dirp(fuse_req_t req, struct fuse_file_info *fi) { - return (struct lo_dirp *)(uintptr_t)fi->fh; + struct lo_data *lo = lo_data(req); + struct lo_map_elem *elem; + + pthread_mutex_lock(&lo->mutex); + elem = lo_map_get(&lo->dirp_map, fi->fh); + pthread_mutex_unlock(&lo->mutex); + if (!elem) { + return NULL; + } + + return elem->dirp; } static void lo_opendir(fuse_req_t req, fuse_ino_t ino, @@ -873,6 +881,7 @@ static void lo_opendir(fuse_req_t req, fuse_ino_t ino, struct lo_data *lo = lo_data(req); struct lo_dirp *d; int fd; + ssize_t fh; d = calloc(1, sizeof(struct lo_dirp)); if (d == NULL) { @@ -892,7 +901,14 @@ static void lo_opendir(fuse_req_t req, fuse_ino_t ino, d->offset = 0; d->entry = NULL; - fi->fh = (uintptr_t)d; + pthread_mutex_lock(&lo->mutex); + fh = lo_add_dirp_mapping(req, d); + pthread_mutex_unlock(&lo->mutex); + if (fh == -1) { + goto out_err; + } + + fi->fh = fh; if (lo->cache == CACHE_ALWAYS) { fi->keep_cache = 1; } @@ -903,6 +919,9 @@ out_errno: error = errno; out_err: if (d) { + if (d->dp) { + closedir(d->dp); + } if (fd != -1) { close(fd); } @@ -920,17 +939,21 @@ static int is_dot_or_dotdot(const char *name) static void lo_do_readdir(fuse_req_t req, fuse_ino_t ino, size_t size, off_t offset, struct fuse_file_info *fi, int plus) { - struct lo_dirp *d = lo_dirp(fi); - char *buf; + struct lo_dirp *d; + char *buf = NULL; char *p; size_t rem = size; - int err; + int err = ENOMEM; (void)ino; + d = lo_dirp(req, fi); + if (!d) { + goto error; + } + buf = calloc(1, size); if (!buf) { - err = ENOMEM; goto error; } p = buf; @@ -1028,8 +1051,21 @@ static void lo_readdirplus(fuse_req_t req, fuse_ino_t ino, size_t size, static void lo_releasedir(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info *fi) { - struct lo_dirp *d = lo_dirp(fi); + struct lo_data *lo = lo_data(req); + struct lo_dirp *d; + (void)ino; + + d = lo_dirp(req, fi); + if (!d) { + fuse_reply_err(req, EBADF); + return; + } + + pthread_mutex_lock(&lo->mutex); + lo_map_remove(&lo->dirp_map, fi->fh); + pthread_mutex_unlock(&lo->mutex); + closedir(d->dp); free(d); fuse_reply_err(req, 0); @@ -1081,8 +1117,18 @@ static void lo_fsyncdir(fuse_req_t req, fuse_ino_t ino, int datasync, struct fuse_file_info *fi) { int res; - int fd = dirfd(lo_dirp(fi)->dp); + struct lo_dirp *d; + int fd; + (void)ino; + + d = lo_dirp(req, fi); + if (!d) { + fuse_reply_err(req, EBADF); + return; + } + + fd = dirfd(d->dp); if (datasync) { res = fdatasync(fd); } else { @@ -1614,6 +1660,8 @@ int main(int argc, char *argv[]) root_elem = lo_map_reserve(&lo.ino_map, lo.root.fuse_ino); root_elem->inode = &lo.root; + lo_map_init(&lo.dirp_map); + if (fuse_parse_cmdline(&args, &opts) != 0) { return 1; } @@ -1710,6 +1758,7 @@ err_out2: err_out1: fuse_opt_free_args(&args); + lo_map_destroy(&lo.dirp_map); lo_map_destroy(&lo.ino_map); if (lo.root.fd >= 0) {