/* * 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 #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 = kstrndup(buf, count, GFP_KERNEL); if (!name) return -ENOSPC; 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); goto out; } pr_info("loaded: %zu\n", test_firmware->size); rc = count; out: mutex_unlock(&test_fw_mutex); kfree(name); return rc; } static DEVICE_ATTR_WO(trigger_request); static DECLARE_COMPLETION(async_fw_done); static void trigger_async_request_cb(const struct firmware *fw, void *context) { test_firmware = fw; complete(&async_fw_done); } static ssize_t trigger_async_request_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { int rc; char *name; name = kstrndup(buf, count, GFP_KERNEL); if (!name) return -ENOSPC; pr_info("loading '%s'\n", name); mutex_lock(&test_fw_mutex); release_firmware(test_firmware); test_firmware = NULL; rc = request_firmware_nowait(THIS_MODULE, 1, name, dev, GFP_KERNEL, NULL, trigger_async_request_cb); if (rc) { pr_info("async load of '%s' failed: %d\n", name, rc); kfree(name); goto out; } /* Free 'name' ASAP, to test for race conditions */ kfree(name); wait_for_completion(&async_fw_done); if (test_firmware) { pr_info("loaded: %zu\n", test_firmware->size); rc = count; } else { pr_err("failed to async load firmware\n"); rc = -ENODEV; } out: mutex_unlock(&test_fw_mutex); return rc; } static DEVICE_ATTR_WO(trigger_async_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; } rc = device_create_file(test_fw_misc_device.this_device, &dev_attr_trigger_async_request); if (rc) { pr_err("could not create async sysfs interface: %d\n", rc); goto remove_file; } pr_warn("interface ready\n"); return 0; remove_file: device_remove_file(test_fw_misc_device.this_device, &dev_attr_trigger_async_request); 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_async_request); 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"); lass='insertions'>+2 2017-02-03tcp: add tcp_mss_clamp() helperEric Dumazet4-23/+8 2017-02-02net: add LINUX_MIB_PFMEMALLOCDROP counterEric Dumazet2-2/+4 2017-02-02net: ipv4: remove fib_lookup.h from devinet.c include listDavid Ahern1-2/+0 2017-02-02net: remove useless pfmemalloc settingEric Dumazet1-1/+0 2017-02-02unix: add ioctl to open a unix socket file with O_PATHAndrey Vagin1-0/+41 2017-02-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller12-104/+93 2017-02-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds10-103/+86 2017-02-01net/sched: act_psample: Remove unnecessary ASSERT_RTNLYotam Gigi1-1/+0 2017-02-01net/sched: act_sample: Fix error path in initYotam Gigi1-1/+4 2017-02-01tcp: fix 0 divide in __tcp_select_window()Eric Dumazet1-2/+4 2017-02-01ipv6: pointer math error in ip6_tnl_parse_tlv_enc_lim()Dan Carpenter1-1/+1 2017-02-01net: ipv6: add NLM_F_APPEND in notifications when applicableDavid Ahern1-0/+3 2017-02-01net: reduce skb_warn_bad_offload() noiseEric Dumazet1-3/+9 2017-02-01net/sched: matchall: Fix configuration raceYotam Gigi1-82/+45 2017-02-01rtnetlink: Handle IFLA_MASTER parameter when processing rtnl_newlinkTheuns Verwoerd1-1/+6