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=-4.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY 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 3784DCA9EAF for ; Thu, 24 Oct 2019 12:12:56 +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 0041820856 for ; Thu, 24 Oct 2019 12:12:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="hr9IPC/6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0041820856 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]:40720 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNbz4-0007sa-ID for qemu-devel@archiver.kernel.org; Thu, 24 Oct 2019 08:12:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39263) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNbHX-0002MP-0A for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:27:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNbHU-0008NN-Cr for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:27:53 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:33757 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 1iNbHU-0008N5-8f for qemu-devel@nongnu.org; Thu, 24 Oct 2019 07:27:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1571916471; 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=zmdeBxGXJeXKGEo7YlK7OvPYcpMZQjpGIwy7oqHxlkg=; b=hr9IPC/6Ls4y7udWpPdll8bv4DsZ4CRorzx28yqth1sfIS7jJl3KXRjoW0b7VTVNOwvaiG P0sRU/RWOgRAlx43plEXz+B0bH9WHn+QQED5nR2ZiBXvN869jyYYKI/c+lPJAak0M0NPEI tT6OnfgY0w1KikrbD/opba38wyTwVOE= 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-118-i-rabJQhPwmiND5h1IXgng-1; Thu, 24 Oct 2019 07:27:47 -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 71EDF800D4C; Thu, 24 Oct 2019 11:27:46 +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 29177166A0; Thu, 24 Oct 2019 11:27:39 +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 05/25] virtiofsd: passthrough_ll: add fd_map to hide file descriptors Date: Thu, 24 Oct 2019 12:26:58 +0100 Message-Id: <20191024112718.34657-6-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: i-rabJQhPwmiND5h1IXgng-1 X-Mimecast-Spam-Score: 0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Stefan Hajnoczi Do not expose file descriptor numbers to clients. This prevents the abuse of internal file descriptors (like stdin/stdout). Signed-off-by: Stefan Hajnoczi --- contrib/virtiofsd/passthrough_ll.c | 113 +++++++++++++++++++++++------ 1 file changed, 92 insertions(+), 21 deletions(-) diff --git a/contrib/virtiofsd/passthrough_ll.c b/contrib/virtiofsd/passthr= ough_ll.c index 9f82166079..a71fbff143 100644 --- a/contrib/virtiofsd/passthrough_ll.c +++ b/contrib/virtiofsd/passthrough_ll.c @@ -60,6 +60,7 @@ struct lo_map_elem { =09union { =09=09struct lo_inode *inode; =09=09struct lo_dirp *dirp; +=09=09int fd; =09=09ssize_t freelist; =09}; =09bool in_use; @@ -107,6 +108,7 @@ struct lo_data { =09struct lo_inode root; /* protected by lo->mutex */ =09struct lo_map ino_map; /* protected by lo->mutex */ =09struct lo_map dirp_map; /* protected by lo->mutex */ +=09struct lo_map fd_map; /* protected by lo->mutex */ }; =20 static const struct fuse_opt lo_opts[] =3D { @@ -241,6 +243,19 @@ static void lo_map_remove(struct lo_map *map, size_t k= ey) =09map->freelist =3D key; } =20 +/* Assumes lo->mutex is held */ +static ssize_t lo_add_fd_mapping(fuse_req_t req, int fd) +{ +=09struct lo_map_elem *elem; + +=09elem =3D lo_map_alloc_elem(&lo_data(req)->fd_map); +=09if (!elem) +=09=09return -1; + +=09elem->fd =3D fd; +=09return elem - lo_data(req)->fd_map.elems; +} + /* Assumes lo->mutex is held */ static ssize_t lo_add_dirp_mapping(fuse_req_t req, struct lo_dirp *dirp) { @@ -350,6 +365,21 @@ static int utimensat_empty_nofollow(struct lo_inode *i= node, =09return utimensat(AT_FDCWD, procname, tv, 0); } =20 +static int lo_fi_fd(fuse_req_t req, struct fuse_file_info *fi) +{ +=09struct lo_data *lo =3D lo_data(req); +=09struct lo_map_elem *elem; + +=09pthread_mutex_lock(&lo->mutex); +=09elem =3D lo_map_get(&lo->fd_map, fi->fh); +=09pthread_mutex_unlock(&lo->mutex); + +=09if (!elem) +=09=09return -1; + +=09return elem->fd; +} + static void lo_setattr(fuse_req_t req, fuse_ino_t ino, struct stat *attr, =09=09 int valid, struct fuse_file_info *fi) { @@ -358,6 +388,7 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, = struct stat *attr, =09struct lo_inode *inode; =09int ifd; =09int res; +=09int fd; =20 =09inode =3D lo_inode(req, ino); =09if (!inode) { @@ -367,9 +398,13 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino,= struct stat *attr, =20 =09ifd =3D inode->fd; =20 +=09/* If fi->fh is invalid we'll report EBADF later */ +=09if (fi) +=09=09fd =3D lo_fi_fd(req, fi); + =09if (valid & FUSE_SET_ATTR_MODE) { =09=09if (fi) { -=09=09=09res =3D fchmod(fi->fh, attr->st_mode); +=09=09=09res =3D fchmod(fd, attr->st_mode); =09=09} else { =09=09=09sprintf(procname, "/proc/self/fd/%i", ifd); =09=09=09res =3D chmod(procname, attr->st_mode); @@ -390,7 +425,7 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, = struct stat *attr, =09} =09if (valid & FUSE_SET_ATTR_SIZE) { =09=09if (fi) { -=09=09=09res =3D ftruncate(fi->fh, attr->st_size); +=09=09=09res =3D ftruncate(fd, attr->st_size); =09=09} else { =09=09=09sprintf(procname, "/proc/self/fd/%i", ifd); =09=09=09res =3D truncate(procname, attr->st_size); @@ -417,7 +452,7 @@ static void lo_setattr(fuse_req_t req, fuse_ino_t ino, = struct stat *attr, =09=09=09tv[1] =3D attr->st_mtim; =20 =09=09if (fi) -=09=09=09res =3D futimens(fi->fh, tv); +=09=09=09res =3D futimens(fd, tv); =09=09else =09=09=09res =3D utimensat_empty_nofollow(inode, tv); =09=09if (res =3D=3D -1) @@ -1041,7 +1076,18 @@ static void lo_create(fuse_req_t req, fuse_ino_t par= ent, const char *name, =09lo_restore_cred(&old); =20 =09if (!err) { -=09=09fi->fh =3D fd; +=09=09ssize_t fh; + +=09=09pthread_mutex_lock(&lo->mutex); +=09=09fh =3D lo_add_fd_mapping(req, fd); +=09=09pthread_mutex_unlock(&lo->mutex); +=09=09if (fh =3D=3D -1) { +=09=09=09close(fd); +=09=09=09fuse_reply_err(req, ENOMEM); +=09=09=09return; +=09=09} + +=09=09fi->fh =3D fh; =09=09err =3D lo_do_lookup(req, parent, name, &e); =09} =09if (lo->cache =3D=3D CACHE_NEVER) @@ -1082,6 +1128,7 @@ static void lo_fsyncdir(fuse_req_t req, fuse_ino_t in= o, int datasync, static void lo_open(fuse_req_t req, fuse_ino_t ino, struct fuse_file_info = *fi) { =09int fd; +=09ssize_t fh; =09char buf[64]; =09struct lo_data *lo =3D lo_data(req); =20 @@ -1110,7 +1157,16 @@ static void lo_open(fuse_req_t req, fuse_ino_t ino, = struct fuse_file_info *fi) =09if (fd =3D=3D -1) =09=09return (void) fuse_reply_err(req, errno); =20 -=09fi->fh =3D fd; +=09pthread_mutex_lock(&lo->mutex); +=09fh =3D lo_add_fd_mapping(req, fd); +=09pthread_mutex_unlock(&lo->mutex); +=09if (fh =3D=3D -1) { +=09=09close(fd); +=09=09fuse_reply_err(req, ENOMEM); +=09=09return; +=09} + +=09fi->fh =3D fh; =09if (lo->cache =3D=3D CACHE_NEVER) =09=09fi->direct_io =3D 1; =09else if (lo->cache =3D=3D CACHE_ALWAYS) @@ -1120,9 +1176,18 @@ static void lo_open(fuse_req_t req, fuse_ino_t ino, = struct fuse_file_info *fi) =20 static void lo_release(fuse_req_t req, fuse_ino_t ino, struct fuse_file_in= fo *fi) { +=09struct lo_data *lo =3D lo_data(req); +=09int fd; + =09(void) ino; =20 -=09close(fi->fh); +=09fd =3D lo_fi_fd(req, fi); + +=09pthread_mutex_lock(&lo->mutex); +=09lo_map_remove(&lo->fd_map, fi->fh); +=09pthread_mutex_unlock(&lo->mutex); + +=09close(fd); =09fuse_reply_err(req, 0); } =20 @@ -1130,7 +1195,7 @@ static void lo_flush(fuse_req_t req, fuse_ino_t ino, = struct fuse_file_info *fi) { =09int res; =09(void) ino; -=09res =3D close(dup(fi->fh)); +=09res =3D close(dup(lo_fi_fd(req, fi))); =09fuse_reply_err(req, res =3D=3D -1 ? errno : 0); } =20 @@ -1155,7 +1220,7 @@ static void lo_fsync(fuse_req_t req, fuse_ino_t ino, = int datasync, =09=09if (fd =3D=3D -1) =09=09=09return (void) fuse_reply_err(req, errno); =09} else -=09=09fd =3D fi->fh; +=09=09fd =3D lo_fi_fd(req, fi); =20 =09if (datasync) =09=09res =3D fdatasync(fd); @@ -1176,7 +1241,7 @@ static void lo_read(fuse_req_t req, fuse_ino_t ino, s= ize_t size, =09=09=09"off=3D%lu)\n", ino, size, (unsigned long) offset); =20 =09buf.buf[0].flags =3D FUSE_BUF_IS_FD | FUSE_BUF_FD_SEEK; -=09buf.buf[0].fd =3D fi->fh; +=09buf.buf[0].fd =3D lo_fi_fd(req, fi); =09buf.buf[0].pos =3D offset; =20 =09fuse_reply_data(req, &buf, FUSE_BUF_SPLICE_MOVE); @@ -1191,7 +1256,7 @@ static void lo_write_buf(fuse_req_t req, fuse_ino_t i= no, =09struct fuse_bufvec out_buf =3D FUSE_BUFVEC_INIT(fuse_buf_size(in_buf)); =20 =09out_buf.buf[0].flags =3D FUSE_BUF_IS_FD | FUSE_BUF_FD_SEEK; -=09out_buf.buf[0].fd =3D fi->fh; +=09out_buf.buf[0].fd =3D lo_fi_fd(req, fi); =09out_buf.buf[0].pos =3D off; =20 =09if (lo_debug(req)) @@ -1234,7 +1299,8 @@ static void lo_fallocate(fuse_req_t req, fuse_ino_t i= no, int mode, =09=09return; =09} =20 -=09err =3D posix_fallocate(fi->fh, offset, length); +=09err =3D posix_fallocate(lo_fi_fd(req, fi), offset, +=09=09=09 length); #endif =20 =09fuse_reply_err(req, err); @@ -1246,7 +1312,7 @@ static void lo_flock(fuse_req_t req, fuse_ino_t ino, = struct fuse_file_info *fi, =09int res; =09(void) ino; =20 -=09res =3D flock(fi->fh, op); +=09res =3D flock(lo_fi_fd(req, fi), op); =20 =09fuse_reply_err(req, res =3D=3D -1 ? errno : 0); } @@ -1458,17 +1524,20 @@ static void lo_copy_file_range(fuse_req_t req, fuse= _ino_t ino_in, off_t off_in, =09=09=09 struct fuse_file_info *fi_out, size_t len, =09=09=09 int flags) { +=09int in_fd, out_fd; =09ssize_t res; =20 -=09if (lo_debug(req)) -=09=09fuse_log(FUSE_LOG_DEBUG, "lo_copy_file_range(ino=3D%" PRIu64 "/fd=3D= %lu, " -=09=09=09=09"off=3D%lu, ino=3D%" PRIu64 "/fd=3D%lu, " -=09=09=09=09"off=3D%lu, size=3D%zd, flags=3D0x%x)\n", -=09=09=09ino_in, fi_in->fh, off_in, ino_out, fi_out->fh, off_out, -=09=09=09len, flags); - -=09res =3D copy_file_range(fi_in->fh, &off_in, fi_out->fh, &off_out, len, -=09=09=09 flags); +=09in_fd =3D lo_fi_fd(req, fi_in); +=09out_fd =3D lo_fi_fd(req, fi_out); + +=09fuse_log(FUSE_LOG_DEBUG, +=09=09 "lo_copy_file_range(ino=3D%" PRIu64 "/fd=3D%d, " +=09=09 "off=3D%lu, ino=3D%" PRIu64 "/fd=3D%d, " +=09=09 "off=3D%lu, size=3D%zd, flags=3D0x%x)\n", +=09=09 ino_in, in_fd, off_in, ino_out, out_fd, off_out, len, +=09=09 flags); + +=09res =3D copy_file_range(in_fd, &off_in, out_fd, &off_out, len, flags); =09if (res < 0) =09=09fuse_reply_err(req, -errno); =09else @@ -1552,6 +1621,7 @@ int main(int argc, char *argv[]) =09root_elem->inode =3D &lo.root; =20 =09lo_map_init(&lo.dirp_map); +=09lo_map_init(&lo.fd_map); =20 =09if (fuse_parse_cmdline(&args, &opts) !=3D 0) =09=09return 1; @@ -1646,6 +1716,7 @@ err_out2: err_out1: =09fuse_opt_free_args(&args); =20 +=09lo_map_destroy(&lo.fd_map); =09lo_map_destroy(&lo.dirp_map); =09lo_map_destroy(&lo.ino_map); =20 --=20 2.23.0