3 files changed, 23 insertions, 2 deletions
diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index 17e90a8994..e5847dce00 100644
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -900,6 +900,26 @@ bool ifname_valid(const char *p) {
         return true;
 }
 
+bool address_label_valid(const char *p) {
+
+        if (isempty(p))
+                return false;
+
+        if (strlen(p) >= IFNAMSIZ)
+                return false;
+
+        while (*p) {
+                if ((uint8_t) *p >= 127U)
+                        return false;
+
+                if ((uint8_t) *p <= 31U)
+                        return false;
+                p++;
+        }
+
+        return true;
+}
+
 int getpeercred(int fd, struct ucred *ucred) {
         socklen_t n = sizeof(struct ucred);
         struct ucred u;
diff --git a/src/basic/socket-util.h b/src/basic/socket-util.h
index 3c42e220e5..73c3a339fc 100644
--- a/src/basic/socket-util.h
+++ b/src/basic/socket-util.h
@@ -126,6 +126,7 @@ int ip_tos_to_string_alloc(int i, char **s);
 int ip_tos_from_string(const char *s);
 
 bool ifname_valid(const char *p);
+bool address_label_valid(const char *p);
 
 int getpeercred(int fd, struct ucred *ucred);
 int getpeersec(int fd, char **ret);
diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index e34793e50b..2e6c763aba 100644
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -821,8 +821,8 @@ int config_parse_label(
         if (r < 0)
                 return r;
 
-        if (strlen(rvalue) >= IFNAMSIZ) {
-                log_syntax(unit, LOG_ERR, filename, line, 0, "Interface label is too long, ignoring assignment: %s", rvalue);
+        if (!address_label_valid(rvalue)) {
+                log_syntax(unit, LOG_ERR, filename, line, 0, "Interface label is too long or invalid, ignoring assignment: %s", rvalue);
                 return 0;
         }