On secure boot enabled systems, the bootloader verifies the kernel
image and possibly the initramfs signatures based on a set of keys. A
soft reboot(kexec) of the system, with the same kernel image and
initramfs, requires access to the original keys to verify the
signatures.
This patch allows IMA-appraisal access to those original keys, now
loaded on the platform keyring, needed for verifying the kernel image
and initramfs signatures.
Signed-off-by: Nayna Jain <nayna@xxxxxxxxxxxxx>
Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
---
security/integrity/ima/ima_appraise.c | 11 ++++++++++-
1 file changed, 10 insertions(+), 1 deletion(-)
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index deec1804a00a..9c13585e7d3e 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -294,7 +294,16 @@ int ima_appraise_measurement(enum ima_hooks func,
iint->ima_hash->length);
if (rc == -EOPNOTSUPP) {
status = INTEGRITY_UNKNOWN;
- } else if (rc) {
+ break;
+ }
+ if (rc && func == KEXEC_KERNEL_CHECK)
+ rc = integrity_digsig_verify(
+ INTEGRITY_KEYRING_PLATFORM,
+ (const char *)xattr_value,
+ xattr_len,
+ iint->ima_hash->digest,
+ iint->ima_hash->length);
+ if (rc) {
cause = "invalid-signature";
status = INTEGRITY_FAIL;
} else {
--
2.13.6
