socket-util: refuse "all" and "default" as valid ifnames

Let's avoid collisions with special sysctls.

diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index 8267988ad9c7f469d7761507099dd53e4e801313..06387bdfd6d2cdb3bcdd5378ecd68eca6fb678c5 100644 (file)
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -736,6 +736,11 @@ bool ifname_valid_full(const char *p, IfnameValidFlags flags) {
         if (dot_or_dot_dot(p))
                 return false;
 
+        /* Let's refuse "all" and "default" as interface name, to avoid collisions with the special sysctl
+         * directories /proc/sys/net/{ipv4,ipv6}/conf/{all,default} */
+        if (STR_IN_SET(p, "all", "default"))
+                return false;
+
         for (const char *t = p; *t; t++) {
                 if ((unsigned char) *t >= 127U)
                         return false;