diff options
Diffstat (limited to 'drivers/base/firmware_loader/main.c')
| -rw-r--r-- | drivers/base/firmware_loader/main.c | 247 |
1 files changed, 166 insertions, 81 deletions
diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index 017c4cdb219e..4ebdca9e4da4 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -93,6 +93,7 @@ static inline struct fw_priv *to_fw_priv(struct kref *ref) DEFINE_MUTEX(fw_lock); struct firmware_cache fw_cache; +bool fw_load_abort_all; void fw_state_init(struct fw_priv *fw_priv) { @@ -493,9 +494,9 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, const void *in_buffer)) { size_t size; - int i, len; + int i, len, maxlen = 0; int rc = -ENOENT; - char *path; + char *path, *nt = NULL; size_t msize = INT_MAX; void *buffer = NULL; @@ -518,8 +519,17 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, if (!fw_path[i][0]) continue; - len = snprintf(path, PATH_MAX, "%s/%s%s", - fw_path[i], fw_priv->fw_name, suffix); + /* strip off \n from customized path */ + maxlen = strlen(fw_path[i]); + if (i == 0) { + nt = strchr(fw_path[i], '\n'); + if (nt) + maxlen = nt - fw_path[i]; + } + + len = snprintf(path, PATH_MAX, "%.*s/%s%s", + maxlen, fw_path[i], + fw_priv->fw_name, suffix); if (len >= PATH_MAX) { rc = -ENAMETOOLONG; break; @@ -541,12 +551,16 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, file_size_ptr, READING_FIRMWARE); if (rc < 0) { - if (rc != -ENOENT) - dev_warn(device, "loading %s failed with error %d\n", - path, rc); - else - dev_dbg(device, "loading %s failed for no such file or directory.\n", - path); + if (!(fw_priv->opt_flags & FW_OPT_NO_WARN)) { + if (rc != -ENOENT) + dev_warn(device, + "loading %s failed with error %d\n", + path, rc); + else + dev_dbg(device, + "loading %s failed for no such file or directory.\n", + path); + } continue; } size = rc; @@ -791,6 +805,23 @@ static void fw_abort_batch_reqs(struct firmware *fw) mutex_unlock(&fw_lock); } +#if defined(CONFIG_FW_LOADER_DEBUG) +#include <crypto/sha2.h> + +static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device) +{ + u8 digest[SHA256_DIGEST_SIZE]; + + sha256(fw->data, fw->size, digest); + dev_dbg(device, "Loaded FW: %s, sha256: %*phN\n", + name, SHA256_DIGEST_SIZE, digest); +} +#else +static void fw_log_firmware_info(const struct firmware *fw, const char *name, + struct device *device) +{} +#endif + /* called from request_firmware() and request_firmware_work_func() */ static int _request_firmware(const struct firmware **firmware_p, const char *name, @@ -798,8 +829,6 @@ _request_firmware(const struct firmware **firmware_p, const char *name, size_t offset, u32 opt_flags) { struct firmware *fw = NULL; - struct cred *kern_cred = NULL; - const struct cred *old_cred; bool nondirect = false; int ret; @@ -811,6 +840,25 @@ _request_firmware(const struct firmware **firmware_p, const char *name, goto out; } + + /* + * Reject firmware file names with ".." path components. + * There are drivers that construct firmware file names from + * device-supplied strings, and we don't want some device to be + * able to tell us "I would like to be sent my firmware from + * ../../../etc/shadow, please". + * + * This intentionally only looks at the firmware name, not at + * the firmware base directory or at symlink contents. + */ + if (name_contains_dotdot(name)) { + dev_warn(device, + "Firmware load for '%s' refused, path contains '..' component\n", + name); + ret = -EINVAL; + goto out; + } + ret = _request_firmware_prepare(&fw, name, device, buf, size, offset, opt_flags); if (ret <= 0) /* error or already assigned */ @@ -821,51 +869,46 @@ _request_firmware(const struct firmware **firmware_p, const char *name, * called by a driver when serving an unrelated request from userland, we use * the kernel credentials to read the file. */ - kern_cred = prepare_kernel_cred(&init_task); - if (!kern_cred) { - ret = -ENOMEM; - goto out; - } - old_cred = override_creds(kern_cred); + scoped_with_kernel_creds() { + ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL); - ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL); - - /* Only full reads can support decompression, platform, and sysfs. */ - if (!(opt_flags & FW_OPT_PARTIAL)) - nondirect = true; + /* Only full reads can support decompression, platform, and sysfs. */ + if (!(opt_flags & FW_OPT_PARTIAL)) + nondirect = true; #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD - if (ret == -ENOENT && nondirect) - ret = fw_get_filesystem_firmware(device, fw->priv, ".zst", - fw_decompress_zstd); + if (ret == -ENOENT && nondirect) + ret = fw_get_filesystem_firmware(device, fw->priv, ".zst", + fw_decompress_zstd); #endif #ifdef CONFIG_FW_LOADER_COMPRESS_XZ - if (ret == -ENOENT && nondirect) - ret = fw_get_filesystem_firmware(device, fw->priv, ".xz", - fw_decompress_xz); + if (ret == -ENOENT && nondirect) + ret = fw_get_filesystem_firmware(device, fw->priv, ".xz", + fw_decompress_xz); #endif - if (ret == -ENOENT && nondirect) - ret = firmware_fallback_platform(fw->priv); + if (ret == -ENOENT && nondirect) + ret = firmware_fallback_platform(fw->priv); - if (ret) { - if (!(opt_flags & FW_OPT_NO_WARN)) - dev_warn(device, - "Direct firmware load for %s failed with error %d\n", - name, ret); - if (nondirect) - ret = firmware_fallback_sysfs(fw, name, device, - opt_flags, ret); - } else - ret = assign_fw(fw, device); - - revert_creds(old_cred); - put_cred(kern_cred); + if (ret) { + if (!(opt_flags & FW_OPT_NO_WARN)) + dev_warn(device, + "Direct firmware load for %s failed with error %d\n", + name, ret); + if (nondirect) + ret = firmware_fallback_sysfs(fw, name, device, + opt_flags, ret); + } else { + ret = assign_fw(fw, device); + } + } - out: +out: if (ret < 0) { fw_abort_batch_reqs(fw); release_firmware(fw); fw = NULL; + } else { + fw_log_firmware_info(fw, name, device); } *firmware_p = fw; @@ -886,6 +929,8 @@ _request_firmware(const struct firmware **firmware_p, const char *name, * @name will be used as $FIRMWARE in the uevent environment and * should be distinctive enough not to be confused with any other * firmware image for this or any other device. + * It must not contain any ".." path components - "foo/bar..bin" is + * allowed, but "foo/../bar.bin" is not. * * Caller must hold the reference count of @device. * @@ -985,8 +1030,8 @@ EXPORT_SYMBOL_GPL(firmware_request_platform); /** * firmware_request_cache() - cache firmware for suspend so resume can use it - * @name: name of firmware file * @device: device for which firmware should be cached for + * @name: name of firmware file * * There are some devices with an optimization that enables the device to not * require loading firmware on system reboot. This optimization may still @@ -1112,34 +1157,11 @@ static void request_firmware_work_func(struct work_struct *work) kfree(fw_work); } -/** - * request_firmware_nowait() - asynchronous version of request_firmware - * @module: module requesting the firmware - * @uevent: sends uevent to copy the firmware image if this flag - * is non-zero else the firmware copy must be done manually. - * @name: name of firmware file - * @device: device for which firmware is being loaded - * @gfp: allocation flags - * @context: will be passed over to @cont, and - * @fw may be %NULL if firmware request fails. - * @cont: function will be called asynchronously when the firmware - * request is over. - * - * Caller must hold the reference count of @device. - * - * Asynchronous variant of request_firmware() for user contexts: - * - sleep for as small periods as possible since it may - * increase kernel boot time of built-in device drivers - * requesting firmware in their ->probe() methods, if - * @gfp is GFP_KERNEL. - * - * - can't sleep at all if @gfp is GFP_ATOMIC. - **/ -int -request_firmware_nowait( + +static int _request_firmware_nowait( struct module *module, bool uevent, const char *name, struct device *device, gfp_t gfp, void *context, - void (*cont)(const struct firmware *fw, void *context)) + void (*cont)(const struct firmware *fw, void *context), bool nowarn) { struct firmware_work *fw_work; @@ -1157,7 +1179,8 @@ request_firmware_nowait( fw_work->context = context; fw_work->cont = cont; fw_work->opt_flags = FW_OPT_NOWAIT | - (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER); + (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER) | + (nowarn ? FW_OPT_NO_WARN : 0); if (!uevent && fw_cache_is_setup(device, name)) { kfree_const(fw_work->name); @@ -1176,8 +1199,66 @@ request_firmware_nowait( schedule_work(&fw_work->work); return 0; } + +/** + * request_firmware_nowait() - asynchronous version of request_firmware + * @module: module requesting the firmware + * @uevent: sends uevent to copy the firmware image if this flag + * is non-zero else the firmware copy must be done manually. + * @name: name of firmware file + * @device: device for which firmware is being loaded + * @gfp: allocation flags + * @context: will be passed over to @cont, and + * @fw may be %NULL if firmware request fails. + * @cont: function will be called asynchronously when the firmware + * request is over. + * + * Caller must hold the reference count of @device. + * + * Asynchronous variant of request_firmware() for user contexts: + * - sleep for as small periods as possible since it may + * increase kernel boot time of built-in device drivers + * requesting firmware in their ->probe() methods, if + * @gfp is GFP_KERNEL. + * + * - can't sleep at all if @gfp is GFP_ATOMIC. + **/ +int request_firmware_nowait( + struct module *module, bool uevent, + const char *name, struct device *device, gfp_t gfp, void *context, + void (*cont)(const struct firmware *fw, void *context)) +{ + return _request_firmware_nowait(module, uevent, name, device, gfp, + context, cont, false); + +} EXPORT_SYMBOL(request_firmware_nowait); +/** + * firmware_request_nowait_nowarn() - async version of request_firmware_nowarn + * @module: module requesting the firmware + * @name: name of firmware file + * @device: device for which firmware is being loaded + * @gfp: allocation flags + * @context: will be passed over to @cont, and + * @fw may be %NULL if firmware request fails. + * @cont: function will be called asynchronously when the firmware + * request is over. + * + * Similar in function to request_firmware_nowait(), but doesn't print a warning + * when the firmware file could not be found and always sends a uevent to copy + * the firmware image. + */ +int firmware_request_nowait_nowarn( + struct module *module, const char *name, + struct device *device, gfp_t gfp, void *context, + void (*cont)(const struct firmware *fw, void *context)) +{ + return _request_firmware_nowait(module, FW_ACTION_UEVENT, name, device, + gfp, context, cont, true); +} +EXPORT_SYMBOL_GPL(firmware_request_nowait_nowarn); + #ifdef CONFIG_FW_CACHE static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain); @@ -1469,10 +1550,10 @@ static int fw_pm_notify(struct notifier_block *notify_block, case PM_SUSPEND_PREPARE: case PM_RESTORE_PREPARE: /* - * kill pending fallback requests with a custom fallback - * to avoid stalling suspend. + * Here, kill pending fallback requests will only kill + * non-uevent firmware request to avoid stalling suspend. */ - kill_pending_fw_fallback_reqs(true); + kill_pending_fw_fallback_reqs(false); device_cache_fw_images(); break; @@ -1495,16 +1576,20 @@ static int fw_pm_notify(struct notifier_block *notify_block, } /* stop caching firmware once syscore_suspend is reached */ -static int fw_suspend(void) +static int fw_suspend(void *data) { fw_cache.state = FW_LOADER_NO_CACHE; return 0; } -static struct syscore_ops fw_syscore_ops = { +static const struct syscore_ops fw_syscore_ops = { .suspend = fw_suspend, }; +static struct syscore fw_syscore = { + .ops = &fw_syscore_ops, +}; + static int __init register_fw_pm_ops(void) { int ret; @@ -1520,14 +1605,14 @@ static int __init register_fw_pm_ops(void) if (ret) return ret; - register_syscore_ops(&fw_syscore_ops); + register_syscore(&fw_syscore); return ret; } static inline void unregister_fw_pm_ops(void) { - unregister_syscore_ops(&fw_syscore_ops); + unregister_syscore(&fw_syscore); unregister_pm_notifier(&fw_cache.pm_notify); } #else @@ -1557,7 +1642,7 @@ static int fw_shutdown_notify(struct notifier_block *unused1, * Kill all pending fallback requests to avoid both stalling shutdown, * and avoid a deadlock with the usermode_lock. */ - kill_pending_fw_fallback_reqs(false); + kill_pending_fw_fallback_reqs(true); return NOTIFY_DONE; } |
