Names of user-provided fw_cfg items are supposed to start
with "opt/". However FW_CFG_DATA_GENERATOR items are generated
by QEMU, so allow the "etc/" namespace in this specific case.
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <
20200623172726.21040-5-philmd@redhat.com>
Use of names not beginning with "opt/" is potentially dangerous and
entirely unsupported. QEMU will warn if you try.
+Use of names not beginning with "opt/" is tolerated with 'gen_id' (that
+is, the warning is suppressed), but you must know exactly what you're
+doing.
+
All externally provided fw_cfg items are read-only to the guest.
FW_CFG_MAX_FILE_PATH - 1);
return -1;
}
- if (strncmp(name, "opt/", 4) != 0) {
+ if (nonempty_str(gen_id)) {
+ /*
+ * In this particular case where the content is populated
+ * internally, the "etc/" namespace protection is relaxed,
+ * so do not emit a warning.
+ */
+ } else if (strncmp(name, "opt/", 4) != 0) {
warn_report("externally provided fw_cfg item names "
"should be prefixed with \"opt/\"");
}