Commit 3c8069b0 authored by Russell Currey's avatar Russell Currey Committed by Michael Ellerman
Browse files

integrity/powerpc: Improve error handling & reporting when loading certs 



A few improvements to load_powerpc.c:

 - include integrity.h for the pr_fmt()
 - move all error reporting out of get_cert_list()
 - use ERR_PTR() to better preserve error detail
 - don't use pr_err() for missing keys

Reviewed-by: default avatarMimi Zohar <zohar@linux.ibm.com>
Signed-off-by: default avatarRussell Currey <ruscur@russell.cc>
Signed-off-by: default avatarAndrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230210080401.345462-26-ajd@linux.ibm.com
parent ccadf154

security/integrity/platform_certs/load_powerpc.c

+20 −6
Original line number Diff line number Diff line
@@ -14,9 +14,15 @@ 
#include <asm/secure_boot.h>

#include <asm/secvar.h>

#include "keyring_handler.h"

#include "../integrity.h"



/*

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

 *

 * Returns:

 *  - a pointer to a kmalloc'd buffer containing the cert list on success

 *  - NULL if the key does not exist

 *  - an ERR_PTR on error

 */

static __init void *get_cert_list(u8 *key, unsigned long keylen, u64 *size)

{
@@ -25,19 +31,19 @@ static __init void *get_cert_list(u8 *key, unsigned long keylen, u64 *size) 


	rc = secvar_ops->get(key, keylen, NULL, size);

	if (rc) {

		pr_err("Couldn't get size: %d\n", rc);

		if (rc == -ENOENT)

			return NULL;

		return ERR_PTR(rc);

	}



	db = kmalloc(*size, GFP_KERNEL);

	if (!db)

		return NULL;

		return ERR_PTR(-ENOMEM);



	rc = secvar_ops->get(key, keylen, db, size);

	if (rc) {

		kfree(db);

		pr_err("Error reading %s var: %d\n", key, rc);

		return NULL;

		return ERR_PTR(rc);

	}



	return db;
@@ -69,7 +75,11 @@ static int __init load_powerpc_certs(void) 
	 */

	db = get_cert_list("db", 3, &dbsize);

	if (!db) {

		pr_err("Couldn't get db list from firmware\n");

		pr_info("Couldn't get db list from firmware\n");

	} else if (IS_ERR(db)) {

		rc = PTR_ERR(db);

		pr_err("Error reading db from firmware: %d\n", rc);

		return rc;

	} else {

		rc = parse_efi_signature_list("powerpc:db", db, dbsize,

					      get_handler_for_db);
@@ -81,6 +91,10 @@ static int __init load_powerpc_certs(void) 
	dbx = get_cert_list("dbx", 4,  &dbxsize);

	if (!dbx) {

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

	} else if (IS_ERR(dbx)) {

		rc = PTR_ERR(dbx);

		pr_err("Error reading dbx from firmware: %d\n", rc);

		return rc;

	} else {

		rc = parse_efi_signature_list("powerpc:dbx", dbx, dbxsize,

					      get_handler_for_dbx);