File 0011-commands-pgp-Unregister-the-check_signatures-hooks-o.patch of Package grub2
From a496d7fbb80826b341ec1a578704dd574b716d68 Mon Sep 17 00:00:00 2001
From: B Horn <b@horn.uk>
Date: Fri, 1 Nov 2024 19:24:29 +0000
Subject: [PATCH 11/20] commands/pgp: Unregister the "check_signatures" hooks
on module unload
If the hooks are not removed they can be called after the module has
been unloaded leading to an use-after-free.
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>
---
grub-core/commands/pgp.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/grub-core/commands/pgp.c b/grub-core/commands/pgp.c
index 847a5046a5..fa3ef5c754 100644
--- a/grub-core/commands/pgp.c
+++ b/grub-core/commands/pgp.c
@@ -982,6 +982,8 @@ GRUB_MOD_INIT(pgp)
GRUB_MOD_FINI(pgp)
{
+ grub_register_variable_hook ("check_signatures", NULL, NULL);
+ grub_env_unset ("check_signatures");
grub_verifier_unregister (&grub_pubkey_verifier);
grub_unregister_extcmd (cmd);
grub_unregister_extcmd (cmd_trust);
--
2.48.1