From 3ce5852ec6add45a28fe1706e9163351940e905c Mon Sep 17 00:00:00 2001

From: Peter Jones <pjones@redhat.com>

Date: Mon, 2 Oct 2017 18:25:29 -0400

Subject: [PATCH 1/3] Make get_cert_list() not complain about cert lists that

 aren't present.

Signed-off-by: Peter Jones <pjones@redhat.com>

---

 security/integrity/platform_certs/load_uefi.c | 37 ++++++++++++++++++++++---------------

 1 file changed, 22 insertions(+), 15 deletions(-)

diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c

index 81b19c52832b..e188f3ecbce3 100644

--- a/security/integrity/platform_certs/load_uefi.c

+++ b/security/integrity/platform_certs/load_uefi.c

@@ -38,8 +38,8 @@ static __init bool uefi_check_ignore_db(void)

 /*

  * Get a certificate list blob from the named EFI variable.

  */

-static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid,

-				  unsigned long *size)

+static __init int get_cert_list(efi_char16_t *name, efi_guid_t *guid,

+				  unsigned long *size , void **cert_list)

 {

 	efi_status_t status;

 	unsigned long lsize = 4;

@@ -47,24 +47,31 @@ static __init void *get_cert_list(efi_char16_t *name, efi_guid_t *guid,

 	void *db;

 	status = efi.get_variable(name, guid, NULL, &lsize, &tmpdb);

+	if (status == EFI_NOT_FOUND) {

+		*size = 0;

+		*cert_list = NULL;

+		return 0;

+	}

+

 	if (status != EFI_BUFFER_TOO_SMALL) {

 		pr_err("Couldn't get size: 0x%lx\n", status);

-		return NULL;

+		return efi_status_to_err(status);

 	}

 	db = kmalloc(lsize, GFP_KERNEL);

 	if (!db)

-		return NULL;

+		return -ENOMEM;

 	status = efi.get_variable(name, guid, NULL, &lsize, db);

 	if (status != EFI_SUCCESS) {

 		kfree(db);

 		pr_err("Error reading db var: 0x%lx\n", status);

-		return NULL;

+		return efi_status_to_err(status);

 	}

 	*size = lsize;

-	return db;

+	*cert_list = db;

+	return 0;

 }

 /*

@@ -153,10 +160,10 @@ static int __init load_uefi_certs(void)

 	 * an error if we can't get them.

 	 */

 	if (!uefi_check_ignore_db()) {

-		db = get_cert_list(L"db", &secure_var, &dbsize);

-		if (!db) {

+		rc = get_cert_list(L"db", &secure_var, &dbsize, &db);

+		if (rc < 0) {

 			pr_err("MODSIGN: Couldn't get UEFI db list\n");

-		} else {

+		} else if (dbsize != 0) {

 			rc = parse_efi_signature_list("UEFI:db",

 					db, dbsize, get_handler_for_db);

 			if (rc)

@@ -166,10 +173,10 @@ static int __init load_uefi_certs(void)

 		}

 	}

-	mok = get_cert_list(L"MokListRT", &mok_var, &moksize);

-	if (!mok) {

+	rc = get_cert_list(L"MokListRT", &mok_var, &moksize, &mok;;

+	if (rc < 0) {

 		pr_info("Couldn't get UEFI MokListRT\n");

-	} else {

+	} else if (moksize != 0) {

 		rc = parse_efi_signature_list("UEFI:MokListRT",

 					      mok, moksize, get_handler_for_db);

 		if (rc)

@@ -177,10 +184,10 @@ static int __init load_uefi_certs(void)

 		kfree(mok);

 	}

-	dbx = get_cert_list(L"dbx", &secure_var, &dbxsize);

-	if (!dbx) {

+	rc = get_cert_list(L"dbx", &secure_var, &dbxsize, &dbx;;

+	if (rc < 0) {

 		pr_info("Couldn't get UEFI dbx list\n");

-	} else {

+	} else if (dbxsize != 0) {

 		rc = parse_efi_signature_list("UEFI:dbx",

 					      dbx, dbxsize,

 					      get_handler_for_dbx);