From 0a8adf584759cbcbce5d88d419db01a8d0373abf Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 14 Jul 2014 14:38:12 -0700 Subject: test: add firmware_class loader test This provides a simple interface to trigger the firmware_class loader to test built-in, filesystem, and user helper modes. Additionally adds tests via the new interface to the selftests tree. Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- lib/Kconfig.debug | 13 ++++++ lib/Makefile | 1 + lib/test_firmware.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 131 insertions(+) create mode 100644 lib/test_firmware.c (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 7a638aa3545b..213cd9f7e957 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1649,6 +1649,19 @@ config TEST_BPF If unsure, say N. +config TEST_FIRMWARE + tristate "Test firmware loading via userspace interface" + default n + depends on FW_LOADER + help + This builds the "test_firmware" module that creates a userspace + interface for testing firmware loading. This can be used to + control the triggering of firmware loading without needing an + actual firmware-using device. The contents can be rechecked by + userspace. + + If unsure, say N. + source "samples/Kconfig" source "lib/Kconfig.kgdb" diff --git a/lib/Makefile b/lib/Makefile index ba967a19edba..230b4b1456d6 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o obj-$(CONFIG_TEST_MODULE) += test_module.o obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o obj-$(CONFIG_TEST_BPF) += test_bpf.o +obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o ifeq ($(CONFIG_DEBUG_KOBJECT),y) CFLAGS_kobject.o += -DDEBUG diff --git a/lib/test_firmware.c b/lib/test_firmware.c new file mode 100644 index 000000000000..86374c1c49a4 --- /dev/null +++ b/lib/test_firmware.c @@ -0,0 +1,117 @@ +/* + * This module provides an interface to trigger and test firmware loading. + * + * It is designed to be used for basic evaluation of the firmware loading + * subsystem (for example when validating firmware verification). It lacks + * any extra dependencies, and will not normally be loaded by the system + * unless explicitly requested by name. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +static DEFINE_MUTEX(test_fw_mutex); +static const struct firmware *test_firmware; + +static ssize_t test_fw_misc_read(struct file *f, char __user *buf, + size_t size, loff_t *offset) +{ + ssize_t rc = 0; + + mutex_lock(&test_fw_mutex); + if (test_firmware) + rc = simple_read_from_buffer(buf, size, offset, + test_firmware->data, + test_firmware->size); + mutex_unlock(&test_fw_mutex); + return rc; +} + +static const struct file_operations test_fw_fops = { + .owner = THIS_MODULE, + .read = test_fw_misc_read, +}; + +static struct miscdevice test_fw_misc_device = { + .minor = MISC_DYNAMIC_MINOR, + .name = "test_firmware", + .fops = &test_fw_fops, +}; + +static ssize_t trigger_request_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + int rc; + char *name; + + name = kzalloc(count + 1, GFP_KERNEL); + if (!name) + return -ENOSPC; + memcpy(name, buf, count); + + pr_info("loading '%s'\n", name); + + mutex_lock(&test_fw_mutex); + release_firmware(test_firmware); + test_firmware = NULL; + rc = request_firmware(&test_firmware, name, dev); + if (rc) + pr_info("load of '%s' failed: %d\n", name, rc); + pr_info("loaded: %zu\n", test_firmware ? test_firmware->size : 0); + mutex_unlock(&test_fw_mutex); + + kfree(name); + + return count; +} +static DEVICE_ATTR_WO(trigger_request); + +static int __init test_firmware_init(void) +{ + int rc; + + rc = misc_register(&test_fw_misc_device); + if (rc) { + pr_err("could not register misc device: %d\n", rc); + return rc; + } + rc = device_create_file(test_fw_misc_device.this_device, + &dev_attr_trigger_request); + if (rc) { + pr_err("could not create sysfs interface: %d\n", rc); + goto dereg; + } + + pr_warn("interface ready\n"); + + return 0; +dereg: + misc_deregister(&test_fw_misc_device); + return rc; +} + +module_init(test_firmware_init); + +static void __exit test_firmware_exit(void) +{ + release_firmware(test_firmware); + device_remove_file(test_fw_misc_device.this_device, + &dev_attr_trigger_request); + misc_deregister(&test_fw_misc_device); + pr_warn("removed interface\n"); +} + +module_exit(test_firmware_exit); + +MODULE_AUTHOR("Kees Cook "); +MODULE_LICENSE("GPL"); -- cgit v1.2.3