fs/iso9660: Fix multi-extent splicing on non-Rock-Ridge images

Author: Mintsuki

common/fs/iso9660.s2.c

@@ -425,10 +425,11 @@ struct file_handle *iso9660_open(struct volume *vol, const char *path) {
             uint64_t total_size = entry->extent_size.little;
             struct iso9660_directory_entry *e = entry;
 
+            // load_name returns false on the ISO-9660 fallback path but
+            // still populates the buffer; treat an empty buffer as the only
+            // "no usable name" case.
             char base_name[256];
-            if (!load_name(base_name, sizeof(base_name), entry)) {
-                base_name[0] = '\0';
-            }
+            load_name(base_name, sizeof(base_name), entry);
 
             while (e->flags & ISO9660_FLAG_MULTI_EXTENT) {
                 struct iso9660_directory_entry *next = iso9660_next_entry(e, buffer_end);
@@ -438,8 +439,8 @@ struct file_handle *iso9660_open(struct volume *vol, const char *path) {
                 // the file identifier of the first record. Refuse to splice
                 // in unrelated entries.
                 char next_name[256];
-                if (!load_name(next_name, sizeof(next_name), next)
-                 || strcmp(base_name, next_name) != 0) {
+                load_name(next_name, sizeof(next_name), next);
+                if (base_name[0] == '\0' || strcmp(base_name, next_name) != 0) {
                     break;
                 }
                 e = next;