diff options
Diffstat (limited to 'drivers/firmware/efi/efivars.c')
-rw-r--r-- | drivers/firmware/efi/efivars.c | 192 |
1 files changed, 162 insertions, 30 deletions
diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c index 50ea412a25e6..463c56545ae8 100644 --- a/drivers/firmware/efi/efivars.c +++ b/drivers/firmware/efi/efivars.c @@ -69,6 +69,7 @@ #include <linux/module.h> #include <linux/slab.h> #include <linux/ucs2_string.h> +#include <linux/compat.h> #define EFIVARS_VERSION "0.08" #define EFIVARS_DATE "2004-May-17" @@ -86,6 +87,15 @@ static struct kset *efivars_kset; static struct bin_attribute *efivars_new_var; static struct bin_attribute *efivars_del_var; +struct compat_efi_variable { + efi_char16_t VariableName[EFI_VAR_NAME_LEN/sizeof(efi_char16_t)]; + efi_guid_t VendorGuid; + __u32 DataSize; + __u8 Data[1024]; + __u32 Status; + __u32 Attributes; +} __packed; + struct efivar_attribute { struct attribute attr; ssize_t (*show) (struct efivar_entry *entry, char *buf); @@ -189,45 +199,107 @@ efivar_data_read(struct efivar_entry *entry, char *buf) memcpy(buf, var->Data, var->DataSize); return var->DataSize; } -/* - * We allow each variable to be edited via rewriting the - * entire efi variable structure. - */ -static ssize_t -efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) -{ - struct efi_variable *new_var, *var = &entry->var; - int err; - if (count != sizeof(struct efi_variable)) - return -EINVAL; - - new_var = (struct efi_variable *)buf; +static inline int +sanity_check(struct efi_variable *var, efi_char16_t *name, efi_guid_t vendor, + unsigned long size, u32 attributes, u8 *data) +{ /* * If only updating the variable data, then the name * and guid should remain the same */ - if (memcmp(new_var->VariableName, var->VariableName, sizeof(var->VariableName)) || - efi_guidcmp(new_var->VendorGuid, var->VendorGuid)) { + if (memcmp(name, var->VariableName, sizeof(var->VariableName)) || + efi_guidcmp(vendor, var->VendorGuid)) { printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n"); return -EINVAL; } - if ((new_var->DataSize <= 0) || (new_var->Attributes == 0)){ + if ((size <= 0) || (attributes == 0)){ printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n"); return -EINVAL; } - if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || - efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { + if ((attributes & ~EFI_VARIABLE_MASK) != 0 || + efivar_validate(name, data, size) == false) { printk(KERN_ERR "efivars: Malformed variable content\n"); return -EINVAL; } - memcpy(&entry->var, new_var, count); + return 0; +} + +static inline bool is_compat(void) +{ + if (IS_ENABLED(CONFIG_COMPAT) && is_compat_task()) + return true; + + return false; +} + +static void +copy_out_compat(struct efi_variable *dst, struct compat_efi_variable *src) +{ + memcpy(dst->VariableName, src->VariableName, EFI_VAR_NAME_LEN); + memcpy(dst->Data, src->Data, sizeof(src->Data)); + + dst->VendorGuid = src->VendorGuid; + dst->DataSize = src->DataSize; + dst->Attributes = src->Attributes; +} + +/* + * We allow each variable to be edited via rewriting the + * entire efi variable structure. + */ +static ssize_t +efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) +{ + struct efi_variable *new_var, *var = &entry->var; + efi_char16_t *name; + unsigned long size; + efi_guid_t vendor; + u32 attributes; + u8 *data; + int err; + + if (is_compat()) { + struct compat_efi_variable *compat; + + if (count != sizeof(*compat)) + return -EINVAL; + + compat = (struct compat_efi_variable *)buf; + attributes = compat->Attributes; + vendor = compat->VendorGuid; + name = compat->VariableName; + size = compat->DataSize; + data = compat->Data; + + err = sanity_check(var, name, vendor, size, attributes, data); + if (err) + return err; + + copy_out_compat(&entry->var, compat); + } else { + if (count != sizeof(struct efi_variable)) + return -EINVAL; + + new_var = (struct efi_variable *)buf; - err = efivar_entry_set(entry, new_var->Attributes, - new_var->DataSize, new_var->Data, NULL); + attributes = new_var->Attributes; + vendor = new_var->VendorGuid; + name = new_var->VariableName; + size = new_var->DataSize; + data = new_var->Data; + + err = sanity_check(var, name, vendor, size, attributes, data); + if (err) + return err; + + memcpy(&entry->var, new_var, count); + } + + err = efivar_entry_set(entry, attributes, size, data, NULL); if (err) { printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err); return -EIO; @@ -240,6 +312,8 @@ static ssize_t efivar_show_raw(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; + struct compat_efi_variable *compat; + size_t size; if (!entry || !buf) return 0; @@ -249,9 +323,23 @@ efivar_show_raw(struct efivar_entry *entry, char *buf) &entry->var.DataSize, entry->var.Data)) return -EIO; - memcpy(buf, var, sizeof(*var)); + if (is_compat()) { + compat = (struct compat_efi_variable *)buf; + + size = sizeof(*compat); + memcpy(compat->VariableName, var->VariableName, + EFI_VAR_NAME_LEN); + memcpy(compat->Data, var->Data, sizeof(compat->Data)); + + compat->VendorGuid = var->VendorGuid; + compat->DataSize = var->DataSize; + compat->Attributes = var->Attributes; + } else { + size = sizeof(*var); + memcpy(buf, var, size); + } - return sizeof(*var); + return size; } /* @@ -326,15 +414,39 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t pos, size_t count) { + struct compat_efi_variable *compat = (struct compat_efi_variable *)buf; struct efi_variable *new_var = (struct efi_variable *)buf; struct efivar_entry *new_entry; + bool need_compat = is_compat(); + efi_char16_t *name; + unsigned long size; + u32 attributes; + u8 *data; int err; if (!capable(CAP_SYS_ADMIN)) return -EACCES; - if ((new_var->Attributes & ~EFI_VARIABLE_MASK) != 0 || - efivar_validate(new_var, new_var->Data, new_var->DataSize) == false) { + if (need_compat) { + if (count != sizeof(*compat)) + return -EINVAL; + + attributes = compat->Attributes; + name = compat->VariableName; + size = compat->DataSize; + data = compat->Data; + } else { + if (count != sizeof(*new_var)) + return -EINVAL; + + attributes = new_var->Attributes; + name = new_var->VariableName; + size = new_var->DataSize; + data = new_var->Data; + } + + if ((attributes & ~EFI_VARIABLE_MASK) != 0 || + efivar_validate(name, data, size) == false) { printk(KERN_ERR "efivars: Malformed variable content\n"); return -EINVAL; } @@ -343,10 +455,13 @@ static ssize_t efivar_create(struct file *filp, struct kobject *kobj, if (!new_entry) return -ENOMEM; - memcpy(&new_entry->var, new_var, sizeof(*new_var)); + if (need_compat) + copy_out_compat(&new_entry->var, compat); + else + memcpy(&new_entry->var, new_var, sizeof(*new_var)); - err = efivar_entry_set(new_entry, new_var->Attributes, new_var->DataSize, - new_var->Data, &efivar_sysfs_list); + err = efivar_entry_set(new_entry, attributes, size, + data, &efivar_sysfs_list); if (err) { if (err == -EEXIST) err = -EINVAL; @@ -369,15 +484,32 @@ static ssize_t efivar_delete(struct file *filp, struct kobject *kobj, char *buf, loff_t pos, size_t count) { struct efi_variable *del_var = (struct efi_variable *)buf; + struct compat_efi_variable *compat; struct efivar_entry *entry; + efi_char16_t *name; + efi_guid_t vendor; int err = 0; if (!capable(CAP_SYS_ADMIN)) return -EACCES; + if (is_compat()) { + if (count != sizeof(*compat)) + return -EINVAL; + + compat = (struct compat_efi_variable *)buf; + name = compat->VariableName; + vendor = compat->VendorGuid; + } else { + if (count != sizeof(*del_var)) + return -EINVAL; + + name = del_var->VariableName; + vendor = del_var->VendorGuid; + } + efivar_entry_iter_begin(); - entry = efivar_entry_find(del_var->VariableName, del_var->VendorGuid, - &efivar_sysfs_list, true); + entry = efivar_entry_find(name, vendor, &efivar_sysfs_list, true); if (!entry) err = -EINVAL; else if (__efivar_entry_delete(entry)) |