diff --git a/hw/net/xen_nic.c b/hw/net/xen_nic.c
index 5c815b4f0c..7d92c2d022 100644
--- a/hw/net/xen_nic.c
+++ b/hw/net/xen_nic.c
@@ -296,9 +296,8 @@ static int net_init(struct XenLegacyDevice *xendev)
     netdev->nic = qemu_new_nic(&net_xen_info, &netdev->conf,
                                "xen", NULL, netdev);
 
-    snprintf(qemu_get_queue(netdev->nic)->info_str,
-             sizeof(qemu_get_queue(netdev->nic)->info_str),
-             "nic: xenbus vif macaddr=%s", netdev->mac);
+    qemu_set_info_str(qemu_get_queue(netdev->nic),
+                      "nic: xenbus vif macaddr=%s", netdev->mac);
 
     /* fill info */
     xenstore_write_be_int(&netdev->xendev, "feature-rx-copy", 1);
diff --git a/include/net/net.h b/include/net/net.h
index 025dbf1e14..3db75ff841 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -177,6 +177,7 @@ ssize_t qemu_send_packet_async(NetClientState *nc, const uint8_t *buf,
 void qemu_purge_queued_packets(NetClientState *nc);
 void qemu_flush_queued_packets(NetClientState *nc);
 void qemu_flush_or_purge_queued_packets(NetClientState *nc, bool purge);
+void qemu_set_info_str(NetClientState *nc, const char *fmt, ...);
 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6]);
 bool qemu_has_ufo(NetClientState *nc);
 bool qemu_has_vnet_hdr(NetClientState *nc);
diff --git a/net/l2tpv3.c b/net/l2tpv3.c
index af373e5c30..350041a0d6 100644
--- a/net/l2tpv3.c
+++ b/net/l2tpv3.c
@@ -723,8 +723,7 @@ int net_init_l2tpv3(const Netdev *netdev,
 
     l2tpv3_read_poll(s, true);
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "l2tpv3: connected");
+    qemu_set_info_str(&s->nc, "l2tpv3: connected");
     return 0;
 outerr:
     qemu_del_net_client(nc);
diff --git a/net/net.c b/net/net.c
index 128a90f1fd..f29a59cd7f 100644
--- a/net/net.c
+++ b/net/net.c
@@ -141,13 +141,20 @@ char *qemu_mac_strdup_printf(const uint8_t *macaddr)
                            macaddr[3], macaddr[4], macaddr[5]);
 }
 
+void qemu_set_info_str(NetClientState *nc, const char *fmt, ...)
+{
+    va_list ap;
+
+    va_start(ap, fmt);
+    vsnprintf(nc->info_str, sizeof(nc->info_str), fmt, ap);
+    va_end(ap);
+}
+
 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6])
 {
-    snprintf(nc->info_str, sizeof(nc->info_str),
-             "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
-             nc->model,
-             macaddr[0], macaddr[1], macaddr[2],
-             macaddr[3], macaddr[4], macaddr[5]);
+    qemu_set_info_str(nc, "model=%s,macaddr=%02x:%02x:%02x:%02x:%02x:%02x",
+                      nc->model, macaddr[0], macaddr[1], macaddr[2],
+                      macaddr[3], macaddr[4], macaddr[5]);
 }
 
 static int mac_table[256] = {0};
diff --git a/net/slirp.c b/net/slirp.c
index 8679be6444..14a8d59277 100644
--- a/net/slirp.c
+++ b/net/slirp.c
@@ -611,9 +611,8 @@ static int net_slirp_init(NetClientState *peer, const char *model,
 
     nc = qemu_new_net_client(&net_slirp_info, peer, model, name);
 
-    snprintf(nc->info_str, sizeof(nc->info_str),
-             "net=%s,restrict=%s", inet_ntoa(net),
-             restricted ? "on" : "off");
+    qemu_set_info_str(nc, "net=%s,restrict=%s", inet_ntoa(net),
+                      restricted ? "on" : "off");
 
     s = DO_UPCAST(SlirpState, nc, nc);
 
diff --git a/net/socket.c b/net/socket.c
index bfd8596250..ade1ecf38b 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -179,7 +179,7 @@ static void net_socket_send(void *opaque)
         s->fd = -1;
         net_socket_rs_init(&s->rs, net_socket_rs_finalize, false);
         s->nc.link_down = true;
-        memset(s->nc.info_str, 0, sizeof(s->nc.info_str));
+        qemu_set_info_str(&s->nc, "");
 
         return;
     }
@@ -387,16 +387,15 @@ static NetSocketState *net_socket_fd_init_dgram(NetClientState *peer,
     /* mcast: save bound address as dst */
     if (is_connected && mcast != NULL) {
         s->dgram_dst = saddr;
-        snprintf(nc->info_str, sizeof(nc->info_str),
-                 "socket: fd=%d (cloned mcast=%s:%d)",
-                 fd, inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+        qemu_set_info_str(nc, "socket: fd=%d (cloned mcast=%s:%d)", fd,
+                          inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
     } else {
         if (sa_type == SOCKET_ADDRESS_TYPE_UNIX) {
             s->dgram_dst.sin_family = AF_UNIX;
         }
 
-        snprintf(nc->info_str, sizeof(nc->info_str),
-                 "socket: fd=%d %s", fd, SocketAddressType_str(sa_type));
+        qemu_set_info_str(nc, "socket: fd=%d %s", fd,
+                          SocketAddressType_str(sa_type));
     }
 
     return s;
@@ -430,7 +429,7 @@ static NetSocketState *net_socket_fd_init_stream(NetClientState *peer,
 
     nc = qemu_new_net_client(&net_socket_info, peer, model, name);
 
-    snprintf(nc->info_str, sizeof(nc->info_str), "socket: fd=%d", fd);
+    qemu_set_info_str(nc, "socket: fd=%d", fd);
 
     s = DO_UPCAST(NetSocketState, nc, nc);
 
@@ -497,9 +496,8 @@ static void net_socket_accept(void *opaque)
     s->fd = fd;
     s->nc.link_down = false;
     net_socket_connect(s);
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: connection from %s:%d",
-             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: connection from %s:%d",
+                      inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
 }
 
 static int net_socket_listen_init(NetClientState *peer,
@@ -597,9 +595,8 @@ static int net_socket_connect_init(NetClientState *peer,
         return -1;
     }
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: connect to %s:%d",
-             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: connect to %s:%d",
+                      inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
     return 0;
 }
 
@@ -642,9 +639,8 @@ static int net_socket_mcast_init(NetClientState *peer,
 
     s->dgram_dst = saddr;
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: mcast=%s:%d",
-             inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: mcast=%s:%d",
+                      inet_ntoa(saddr.sin_addr), ntohs(saddr.sin_port));
     return 0;
 
 }
@@ -697,9 +693,8 @@ static int net_socket_udp_init(NetClientState *peer,
 
     s->dgram_dst = raddr;
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "socket: udp=%s:%d",
-             inet_ntoa(raddr.sin_addr), ntohs(raddr.sin_port));
+    qemu_set_info_str(&s->nc, "socket: udp=%s:%d", inet_ntoa(raddr.sin_addr),
+                      ntohs(raddr.sin_port));
     return 0;
 }
 
diff --git a/net/tap-win32.c b/net/tap-win32.c
index 7466f22e77..a49c28ba5d 100644
--- a/net/tap-win32.c
+++ b/net/tap-win32.c
@@ -789,8 +789,7 @@ static int tap_win32_init(NetClientState *peer, const char *model,
 
     s = DO_UPCAST(TAPState, nc, nc);
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-             "tap: ifname=%s", ifname);
+    qemu_set_info_str(&s->nc, "tap: ifname=%s", ifname);
 
     s->handle = handle;
 
diff --git a/net/tap.c b/net/tap.c
index e203d07a12..1210a0436d 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -630,8 +630,7 @@ int net_init_bridge(const Netdev *netdev, const char *name,
     }
     s = net_tap_fd_init(peer, "bridge", name, fd, vnet_hdr);
 
-    snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s,br=%s", helper,
-             br);
+    qemu_set_info_str(&s->nc, "helper=%s,br=%s", helper, br);
 
     return 0;
 }
@@ -690,14 +689,12 @@ static void net_init_tap_one(const NetdevTapOptions *tap, NetClientState *peer,
     }
 
     if (tap->has_fd || tap->has_fds) {
-        snprintf(s->nc.info_str, sizeof(s->nc.info_str), "fd=%d", fd);
+        qemu_set_info_str(&s->nc, "fd=%d", fd);
     } else if (tap->has_helper) {
-        snprintf(s->nc.info_str, sizeof(s->nc.info_str), "helper=%s",
-                 tap->helper);
+        qemu_set_info_str(&s->nc, "helper=%s", tap->helper);
     } else {
-        snprintf(s->nc.info_str, sizeof(s->nc.info_str),
-                 "ifname=%s,script=%s,downscript=%s", ifname, script,
-                 downscript);
+        qemu_set_info_str(&s->nc, "ifname=%s,script=%s,downscript=%s", ifname,
+                          script, downscript);
 
         if (strcmp(downscript, "no") != 0) {
             snprintf(s->down_script, sizeof(s->down_script), "%s", downscript);
diff --git a/net/vde.c b/net/vde.c
index 1083916bcf..c0a08662cc 100644
--- a/net/vde.c
+++ b/net/vde.c
@@ -98,8 +98,7 @@ static int net_vde_init(NetClientState *peer, const char *model,
 
     nc = qemu_new_net_client(&net_vde_info, peer, model, name);
 
-    snprintf(nc->info_str, sizeof(nc->info_str), "sock=%s,fd=%d",
-             sock, vde_datafd(vde));
+    qemu_set_info_str(nc, "sock=%s,fd=%d", sock, vde_datafd(vde));
 
     s = DO_UPCAST(VDEState, nc, nc);
 
diff --git a/net/vhost-user.c b/net/vhost-user.c
index b1a0247b59..3a6b90da86 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -341,8 +341,7 @@ static int net_vhost_user_init(NetClientState *peer, const char *device,
     user = g_new0(struct VhostUserState, 1);
     for (i = 0; i < queues; i++) {
         nc = qemu_new_net_client(&net_vhost_user_info, peer, device, name);
-        snprintf(nc->info_str, sizeof(nc->info_str), "vhost-user%d to %s",
-                 i, chr->label);
+        qemu_set_info_str(nc, "vhost-user%d to %s", i, chr->label);
         nc->queue_index = i;
         if (!nc0) {
             nc0 = nc;
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 9c1b25d782..854ebd61ae 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -544,7 +544,7 @@ static NetClientState *net_vhost_vdpa_init(NetClientState *peer,
         nc = qemu_new_net_control_client(&net_vhost_vdpa_cvq_info, peer,
                                          device, name);
     }
-    snprintf(nc->info_str, sizeof(nc->info_str), TYPE_VHOST_VDPA);
+    qemu_set_info_str(nc, TYPE_VHOST_VDPA);
     s = DO_UPCAST(VhostVDPAState, nc, nc);
 
     s->vhost_vdpa.device_fd = vdpa_device_fd;