From: Jiri Bohac <jbohac@suse.cz>
Date: Mon, 19 Aug 2019 17:17:45 -0700
Subject: kexec_file: Restrict at runtime if the kernel is locked down
Patch-mainline: v5.4-rc1
Git-commit: 155bdd30af17e90941589b5db4dab9a29b28c112
References: jsc#SLE-9870

When KEXEC_SIG is not enabled, kernel should not load images through
kexec_file systemcall if the kernel is locked down.

[Modified by David Howells to fit with modifications to the previous patch
 and to return -EPERM if the kernel is locked down for consistency with
 other lockdowns. Modified by Matthew Garrett to remove the IMA
 integration, which will be replaced by integrating with the IMA
 architecture policy patches.]

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
 kernel/kexec_file.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -208,7 +208,7 @@ kimage_validate_signature(struct kimage
 			return ret;
 		}
 
-		return 0;
+		return security_locked_down(LOCKDOWN_KEXEC);
 
 		/* All other errors are fatal, including nomem, unparseable
 		 * signatures and signature check failures - even if signatures