Revert "Always rename an interface to its name specified in config if no NamePolicy...

This reverts commit 55b6530baacf4658a183b15b010a8cf3483fde08.

This commit description says "Always rename an interface to its name specified
in config if no NamePolicy= is specified", but it does much more:
1. It completely changes the meaning of NamePolicy=kernel. Before, it meant that an interface
   with type==NAMEPOLICY_KERNEL would not be renamed. After, the kernel name only works as
   a fallback, if no policy matches.
2. The "if no NamePolicy= is specified" part is not true at all, the interface will be renamed
   according to the specified NamePolicy=.

After 55b6530baacf, the should_rename() function is named very misleadingly: it is only used
to mean "respect kernel predictable name if no naming policy matches".

Let's revert, and start with a clean slate. This fixes #11436.

diff --git a/src/udev/net/link-config.c b/src/udev/net/link-config.c
index 537cc0cdd998c0b5966efe46e9a6890eacafc92c..3a5077ca6aa56115f658482920215f02201d33a8 100644 (file)
--- a/src/udev/net/link-config.c
+++ b/src/udev/net/link-config.c
@@ -310,11 +310,16 @@ static bool should_rename(sd_device *device, bool respect_predictable) {
                 return true;
 
         switch (type) {
+        case NET_NAME_USER:
+        case NET_NAME_RENAMED:
+                /* these were already named by userspace, do not touch again */
+                return false;
         case NET_NAME_PREDICTABLE:
                 /* the kernel claims to have given a predictable name */
                 if (respect_predictable)
                         return false;
                 _fallthrough_;
+        case NET_NAME_ENUM:
         default:
                 /* the name is known to be bad, or of an unknown type */
                 return true;
@@ -435,8 +440,12 @@ int link_config_apply(link_config_ctx *ctx, link_config *config,
                 }
         }
 
-        if (!new_name && should_rename(device, respect_predictable))
-                new_name = config->name;
+        if (should_rename(device, respect_predictable)) {
+                /* if not set by policy, fall back manually set name */
+                if (!new_name)
+                        new_name = config->name;
+        } else
+                new_name = NULL;
 
         switch (config->mac_policy) {
                 case MACPOLICY_PERSISTENT: