qemu/0090-virtiofsd-Prevent-multiply-running-with-same-vhost_u.patch
Cole Robinson 1d442bb612 qemu-4.2.0-4.fc32
virtio-fs support from upstream
2020-01-28 10:36:21 -05:00

128 lines
3.8 KiB
Diff

From: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Date: Mon, 27 Jan 2020 19:01:59 +0000
Subject: [PATCH] virtiofsd: Prevent multiply running with same
vhost_user_socket
MIME-Version: 1.0
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virtiofsd can run multiply even if the vhost_user_socket is same path.
]# ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu -o source=/tmp/share &
[1] 244965
virtio_session_mount: Waiting for vhost-user socket connection...
]# ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu -o source=/tmp/share &
[2] 244966
virtio_session_mount: Waiting for vhost-user socket connection...
]#
The user will get confused about the situation and maybe the cause of the
unexpected problem. So it's better to prevent the multiple running.
Create a regular file under localstatedir directory to exclude the
vhost_user_socket. To create and lock the file, use qemu_write_pidfile()
because the API has some sanity checks and file lock.
Signed-off-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Applied fixes from Stefan's review and moved osdep include
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
(cherry picked from commit 96814800d2b49d18737c36e021c387697ec40c62)
---
tools/virtiofsd/fuse_lowlevel.c | 1 +
tools/virtiofsd/fuse_virtio.c | 49 ++++++++++++++++++++++++++++++++-
2 files changed, 49 insertions(+), 1 deletion(-)
diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
index 440508a6ec..aac282f278 100644
--- a/tools/virtiofsd/fuse_lowlevel.c
+++ b/tools/virtiofsd/fuse_lowlevel.c
@@ -18,6 +18,7 @@
#include <assert.h>
#include <errno.h>
+#include <glib.h>
#include <limits.h>
#include <stdbool.h>
#include <stddef.h>
diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c
index e7bd772805..b7948def27 100644
--- a/tools/virtiofsd/fuse_virtio.c
+++ b/tools/virtiofsd/fuse_virtio.c
@@ -13,11 +13,12 @@
#include "qemu/osdep.h"
#include "qemu/iov.h"
-#include "fuse_virtio.h"
+#include "qapi/error.h"
#include "fuse_i.h"
#include "standard-headers/linux/fuse.h"
#include "fuse_misc.h"
#include "fuse_opt.h"
+#include "fuse_virtio.h"
#include <assert.h>
#include <errno.h>
@@ -743,6 +744,42 @@ int virtio_loop(struct fuse_session *se)
return 0;
}
+static void strreplace(char *s, char old, char new)
+{
+ for (; *s; ++s) {
+ if (*s == old) {
+ *s = new;
+ }
+ }
+}
+
+static bool fv_socket_lock(struct fuse_session *se)
+{
+ g_autofree gchar *sk_name = NULL;
+ g_autofree gchar *pidfile = NULL;
+ g_autofree gchar *dir = NULL;
+ Error *local_err = NULL;
+
+ dir = qemu_get_local_state_pathname("run/virtiofsd");
+
+ if (g_mkdir_with_parents(dir, S_IRWXU) < 0) {
+ fuse_log(FUSE_LOG_ERR, "%s: Failed to create directory %s: %s",
+ __func__, dir, strerror(errno));
+ return false;
+ }
+
+ sk_name = g_strdup(se->vu_socket_path);
+ strreplace(sk_name, '/', '.');
+ pidfile = g_strdup_printf("%s/%s.pid", dir, sk_name);
+
+ if (!qemu_write_pidfile(pidfile, &local_err)) {
+ error_report_err(local_err);
+ return false;
+ }
+
+ return true;
+}
+
static int fv_create_listen_socket(struct fuse_session *se)
{
struct sockaddr_un un;
@@ -758,6 +795,16 @@ static int fv_create_listen_socket(struct fuse_session *se)
return -1;
}
+ if (!strlen(se->vu_socket_path)) {
+ fuse_log(FUSE_LOG_ERR, "Socket path is empty\n");
+ return -1;
+ }
+
+ /* Check the vu_socket_path is already used */
+ if (!fv_socket_lock(se)) {
+ return -1;
+ }
+
/*
* Create the Unix socket to communicate with qemu
* based on QEMU's vhost-user-bridge