gettext: Remove variables hooks on module unload

The gettext module does not entirely cleanup after itself in
its GRUB_MOD_FINI() leaving a few variables hooks in place.
It is not possible to unload gettext module because normal
module depends on it. Though fix the issues for completeness.

Fixes: CVE-2025-0622
Reported-by: B Horn <b@horn.uk>
Signed-off-by: B Horn <b@horn.uk>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

diff --git a/grub-core/gettext/gettext.c b/grub-core/gettext/gettext.c
index 7a1c14e4f33c94e741a9f9595515112c03998dac..e4f4f8ee66d031eef1e550c6d9a0bb40b7212cda 100644 (file)
--- a/grub-core/gettext/gettext.c
+++ b/grub-core/gettext/gettext.c
@@ -535,6 +535,10 @@ GRUB_MOD_INIT (gettext)
 
 GRUB_MOD_FINI (gettext)
 {
+  grub_register_variable_hook ("locale_dir", NULL, NULL);
+  grub_register_variable_hook ("secondary_locale_dir", NULL, NULL);
+  grub_register_variable_hook ("lang", NULL, NULL);
+
   grub_gettext_delete_list (&main_context);
   grub_gettext_delete_list (&secondary_context);