test_firmware: Test platform fw loading on non-EFI systems

On non-EFI systems, it wasn't possible to test the platform firmware
loader because it will have never set "checked_fw" during __init.
Instead, allow the test code to override this check. Additionally split
the declarations into a private symbol namespace so there is greater
enforcement of the symbol visibility.

Fixes: 548193cba2 ("test_firmware: add support for firmware_request_platform")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200909225354.3118328-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Kees Cook 2020-09-09 15:53:54 -07:00 committed by Greg Kroah-Hartman
parent 1c30474826
commit baaabecfc8
3 changed files with 16 additions and 9 deletions

View File

@ -16,9 +16,9 @@
/* Exported for use by lib/test_firmware.c only */
LIST_HEAD(efi_embedded_fw_list);
EXPORT_SYMBOL_GPL(efi_embedded_fw_list);
static bool checked_for_fw;
EXPORT_SYMBOL_NS_GPL(efi_embedded_fw_list, TEST_FIRMWARE);
bool efi_embedded_fw_checked;
EXPORT_SYMBOL_NS_GPL(efi_embedded_fw_checked, TEST_FIRMWARE);
static const struct dmi_system_id * const embedded_fw_table[] = {
#ifdef CONFIG_TOUCHSCREEN_DMI
@ -116,14 +116,14 @@ void __init efi_check_for_embedded_firmwares(void)
}
}
checked_for_fw = true;
efi_embedded_fw_checked = true;
}
int efi_get_embedded_fw(const char *name, const u8 **data, size_t *size)
{
struct efi_embedded_fw *iter, *fw = NULL;
if (!checked_for_fw) {
if (!efi_embedded_fw_checked) {
pr_warn("Warning %s called while we did not check for embedded fw\n",
__func__);
return -ENOENT;

View File

@ -8,8 +8,8 @@
#define EFI_EMBEDDED_FW_PREFIX_LEN 8
/*
* This struct and efi_embedded_fw_list are private to the efi-embedded fw
* implementation they are in this header for use by lib/test_firmware.c only!
* This struct is private to the efi-embedded fw implementation.
* They are in this header for use by lib/test_firmware.c only!
*/
struct efi_embedded_fw {
struct list_head list;
@ -18,8 +18,6 @@ struct efi_embedded_fw {
size_t length;
};
extern struct list_head efi_embedded_fw_list;
/**
* struct efi_embedded_fw_desc - This struct is used by the EFI embedded-fw
* code to search for embedded firmwares.

View File

@ -26,6 +26,8 @@
#include <linux/vmalloc.h>
#include <linux/efi_embedded_fw.h>
MODULE_IMPORT_NS(TEST_FIRMWARE);
#define TEST_FIRMWARE_NAME "test-firmware.bin"
#define TEST_FIRMWARE_NUM_REQS 4
#define TEST_FIRMWARE_BUF_SIZE SZ_1K
@ -489,6 +491,9 @@ static ssize_t trigger_request_store(struct device *dev,
static DEVICE_ATTR_WO(trigger_request);
#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE
extern struct list_head efi_embedded_fw_list;
extern bool efi_embedded_fw_checked;
static ssize_t trigger_request_platform_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
@ -501,6 +506,7 @@ static ssize_t trigger_request_platform_store(struct device *dev,
};
struct efi_embedded_fw efi_embedded_fw;
const struct firmware *firmware = NULL;
bool saved_efi_embedded_fw_checked;
char *name;
int rc;
@ -513,6 +519,8 @@ static ssize_t trigger_request_platform_store(struct device *dev,
efi_embedded_fw.data = (void *)test_data;
efi_embedded_fw.length = sizeof(test_data);
list_add(&efi_embedded_fw.list, &efi_embedded_fw_list);
saved_efi_embedded_fw_checked = efi_embedded_fw_checked;
efi_embedded_fw_checked = true;
pr_info("loading '%s'\n", name);
rc = firmware_request_platform(&firmware, name, dev);
@ -530,6 +538,7 @@ static ssize_t trigger_request_platform_store(struct device *dev,
rc = count;
out:
efi_embedded_fw_checked = saved_efi_embedded_fw_checked;
release_firmware(firmware);
list_del(&efi_embedded_fw.list);
kfree(name);