--- /dev/null
+diff -ruN vsftpd-3.0.3.orig/sysstr.c vsftpd-3.0.3/sysstr.c
+--- vsftpd-3.0.3.orig/sysstr.c 2020-11-17 09:47:03.872923383 +0100
++++ vsftpd-3.0.3/sysstr.c 2020-11-17 09:48:41.219754145 +0100
+@@ -74,19 +74,11 @@
+ int
+ str_open(const struct mystr* p_str, const enum EVSFSysStrOpenMode mode)
+ {
+- enum EVSFSysUtilOpenMode open_mode = kVSFSysUtilOpenUnknown;
+- switch (mode)
+- {
+- case kVSFSysStrOpenReadOnly:
+- open_mode = kVSFSysUtilOpenReadOnly;
+- break;
+- case kVSFSysStrOpenUnknown:
+- /* Fall through */
+- default:
+- bug("unknown mode value in str_open");
+- break;
+- }
+- return vsf_sysutil_open_file(str_getbuf(p_str), open_mode);
++ if (mode == kVSFSysStrOpenReadOnly)
++ return vsf_sysutil_open_file(str_getbuf(p_str), kVSFSysUtilOpenReadOnly);
++
++ bug("unknown mode value in str_open");
++ return -1;
+ }
+
+ int