From f6698f2b03b0db76aff7298ed4de1f9a0e22cc26 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Fri, 25 Sep 2020 13:51:29 +0100 Subject: [PATCH] tools/virtiofsd: add support for --socket-group MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If you like running QEMU as a normal user (very common for TCG runs) but you have to run virtiofsd as a root user you run into connection problems. Adding support for an optional --socket-group allows the users to keep using the command line. Signed-off-by: Alex Bennée Reviewed-by: Stefan Hajnoczi Message-Id: <20200925125147.26943-2-alex.bennee@linaro.org> Signed-off-by: Dr. David Alan Gilbert dgilbert: Split long line --- docs/tools/virtiofsd.rst | 4 ++++ tools/virtiofsd/fuse_i.h | 1 + tools/virtiofsd/fuse_lowlevel.c | 6 ++++++ tools/virtiofsd/fuse_virtio.c | 21 +++++++++++++++++++-- 4 files changed, 30 insertions(+), 2 deletions(-) diff --git a/docs/tools/virtiofsd.rst b/docs/tools/virtiofsd.rst index ae02938a95..7ecee49834 100644 --- a/docs/tools/virtiofsd.rst +++ b/docs/tools/virtiofsd.rst @@ -87,6 +87,10 @@ Options Listen on vhost-user UNIX domain socket at PATH. +.. option:: --socket-group=GROUP + + Set the vhost-user UNIX domain socket gid to GROUP. + .. option:: --fd=FDNUM Accept connections from vhost-user UNIX domain socket file descriptor FDNUM. diff --git a/tools/virtiofsd/fuse_i.h b/tools/virtiofsd/fuse_i.h index 1240828208..492e002181 100644 --- a/tools/virtiofsd/fuse_i.h +++ b/tools/virtiofsd/fuse_i.h @@ -68,6 +68,7 @@ struct fuse_session { size_t bufsize; int error; char *vu_socket_path; + char *vu_socket_group; int vu_listen_fd; int vu_socketfd; struct fv_VuDev *virtio_dev; diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c index 2dd36ec03b..4d1ba2925d 100644 --- a/tools/virtiofsd/fuse_lowlevel.c +++ b/tools/virtiofsd/fuse_lowlevel.c @@ -2523,6 +2523,7 @@ static const struct fuse_opt fuse_ll_opts[] = { LL_OPTION("--debug", debug, 1), LL_OPTION("allow_root", deny_others, 1), LL_OPTION("--socket-path=%s", vu_socket_path, 0), + LL_OPTION("--socket-group=%s", vu_socket_group, 0), LL_OPTION("--fd=%d", vu_listen_fd, 0), LL_OPTION("--thread-pool-size=%d", thread_pool_size, 0), FUSE_OPT_END @@ -2630,6 +2631,11 @@ struct fuse_session *fuse_session_new(struct fuse_args *args, "fuse: --socket-path and --fd cannot be given together\n"); goto out4; } + if (se->vu_socket_group && !se->vu_socket_path) { + fuse_log(FUSE_LOG_ERR, + "fuse: --socket-group can only be used with --socket-path\n"); + goto out4; + } se->bufsize = FUSE_MAX_MAX_PAGES * getpagesize() + FUSE_BUFFER_HEADER_SIZE; diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c index d5c8e98253..89f537f79b 100644 --- a/tools/virtiofsd/fuse_virtio.c +++ b/tools/virtiofsd/fuse_virtio.c @@ -31,6 +31,8 @@ #include #include #include +#include +#include #include #include "contrib/libvhost-user/libvhost-user.h" @@ -924,15 +926,30 @@ static int fv_create_listen_socket(struct fuse_session *se) /* * Unfortunately bind doesn't let you set the mask on the socket, - * so set umask to 077 and restore it later. + * so set umask appropriately and restore it later. */ - old_umask = umask(0077); + if (se->vu_socket_group) { + old_umask = umask(S_IROTH | S_IWOTH | S_IXOTH); + } else { + old_umask = umask(S_IRGRP | S_IWGRP | S_IXGRP | + S_IROTH | S_IWOTH | S_IXOTH); + } if (bind(listen_sock, (struct sockaddr *)&un, addr_len) == -1) { fuse_log(FUSE_LOG_ERR, "vhost socket bind: %m\n"); close(listen_sock); umask(old_umask); return -1; } + if (se->vu_socket_group) { + struct group *g = getgrnam(se->vu_socket_group); + if (g) { + if (!chown(se->vu_socket_path, -1, g->gr_gid)) { + fuse_log(FUSE_LOG_WARNING, + "vhost socket failed to set group to %s (%d)\n", + se->vu_socket_group, g->gr_gid); + } + } + } umask(old_umask); if (listen(listen_sock, 1) == -1) {