[PATCH 2/2] Replace magic for trusting the secondary keyring with #define

From: Yannik Sembritzki
Date: Wed Aug 15 2018 - 15:43:27 EST


Signed-off-by: Yannik Sembritzki <yannik@xxxxxxxxxxxxx>
---
arch/x86/kernel/kexec-bzimage64.c | 2 +-
certs/system_keyring.c | 3 ++-
crypto/asymmetric_keys/pkcs7_key_type.c | 2 +-
include/linux/verification.h | 4 ++++
4 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index 74628275..97d199a3 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -532,7 +532,7 @@ static int bzImage64_cleanup(void *loader_data)
static int bzImage64_verify_sig(const char *kernel, unsigned long kernel_len)
{
return verify_pefile_signature(kernel, kernel_len,
- ((struct key *)1UL),
+ TRUST_SECONDARY_KEYRING,
VERIFYING_KEXEC_PE_SIGNATURE);
}
#endif
diff --git a/certs/system_keyring.c b/certs/system_keyring.c
index 6251d1b2..777ac7d2 100644
--- a/certs/system_keyring.c
+++ b/certs/system_keyring.c
@@ -15,6 +15,7 @@
#include <linux/cred.h>
#include <linux/err.h>
#include <linux/slab.h>
+#include <linux/verification.h>
#include <keys/asymmetric-type.h>
#include <keys/system_keyring.h>
#include <crypto/pkcs7.h>
@@ -230,7 +231,7 @@ int verify_pkcs7_signature(const void *data, size_t len,

if (!trusted_keys) {
trusted_keys = builtin_trusted_keys;
- } else if (trusted_keys == (void *)1UL) {
+ } else if (trusted_keys == TRUST_SECONDARY_KEYRING) {
#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
trusted_keys = secondary_trusted_keys;
#else
diff --git a/crypto/asymmetric_keys/pkcs7_key_type.c b/crypto/asymmetric_keys/pkcs7_key_type.c
index e284d9cb..0783e555 100644
--- a/crypto/asymmetric_keys/pkcs7_key_type.c
+++ b/crypto/asymmetric_keys/pkcs7_key_type.c
@@ -63,7 +63,7 @@ static int pkcs7_preparse(struct key_preparsed_payload *prep)

return verify_pkcs7_signature(NULL, 0,
prep->data, prep->datalen,
- (void *)1UL, usage,
+ TRUST_SECONDARY_KEYRING, usage,
pkcs7_view_content, prep);
}

diff --git a/include/linux/verification.h b/include/linux/verification.h
index a10549a6..5a7f2053 100644
--- a/include/linux/verification.h
+++ b/include/linux/verification.h
@@ -12,6 +12,10 @@
#ifndef _LINUX_VERIFICATION_H
#define _LINUX_VERIFICATION_H

+// Allow both builtin trusted keys and secondary trusted keys
+#ifndef TRUST_SECONDARY_KEYRING
+#define TRUST_SECONDARY_KEYRING ((struct key *)1UL)
+
/*
* The use to which an asymmetric key is being put.
*/
--
2.17.1