diff options
| -rw-r--r-- | arch/x86/platform/efi/efi_64.c | 80 |
1 files changed, 57 insertions, 23 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 58b0f801f66f..319148bd4b05 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -31,6 +31,7 @@ #include <linux/io.h> #include <linux/reboot.h> #include <linux/slab.h> +#include <linux/ucs2_string.h> #include <asm/setup.h> #include <asm/page.h> @@ -211,6 +212,35 @@ void efi_sync_low_kernel_mappings(void) memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries); } +/* + * Wrapper for slow_virt_to_phys() that handles NULL addresses. + */ +static inline phys_addr_t +virt_to_phys_or_null_size(void *va, unsigned long size) +{ + bool bad_size; + + if (!va) + return 0; + + if (virt_addr_valid(va)) + return virt_to_phys(va); + + /* + * A fully aligned variable on the stack is guaranteed not to + * cross a page bounary. Try to catch strings on the stack by + * checking that 'size' is a power of two. + */ + bad_size = size > PAGE_SIZE || !is_power_of_2(size); + + WARN_ON(!IS_ALIGNED((unsigned long)va, size) || bad_size); + + return slow_virt_to_phys(va); +} + +#define virt_to_phys_or_null(addr) \ + virt_to_phys_or_null_size((addr), sizeof(*(addr))) + int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) { unsigned long pfn, text; @@ -494,8 +524,8 @@ static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc) spin_lock(&rtc_lock); - phys_tm = virt_to_phys(tm); - phys_tc = virt_to_phys(tc); + phys_tm = virt_to_phys_or_null(tm); + phys_tc = virt_to_phys_or_null(tc); status = efi_thunk(get_time, phys_tm, phys_tc); @@ -511,7 +541,7 @@ static efi_status_t efi_thunk_set_time(efi_time_t *tm) spin_lock(&rtc_lock); - phys_tm = virt_to_phys(tm); + phys_tm = virt_to_phys_or_null(tm); status = efi_thunk(set_time, phys_tm); @@ -529,9 +559,9 @@ efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending, spin_lock(&rtc_lock); - phys_enabled = virt_to_phys(enabled); - phys_pending = virt_to_phys(pending); - phys_tm = virt_to_phys(tm); + phys_enabled = virt_to_phys_or_null(enabled); + phys_pending = virt_to_phys_or_null(pending); + phys_tm = virt_to_phys_or_null(tm); status = efi_thunk(get_wakeup_time, phys_enabled, phys_pending, phys_tm); @@ -549,7 +579,7 @@ efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) spin_lock(&rtc_lock); - phys_tm = virt_to_phys(tm); + phys_tm = virt_to_phys_or_null(tm); status = efi_thunk(set_wakeup_time, enabled, phys_tm); @@ -558,6 +588,10 @@ efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) return status; } +static unsigned long efi_name_size(efi_char16_t *name) +{ + return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1; +} static efi_status_t efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor, @@ -567,11 +601,11 @@ efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor, u32 phys_name, phys_vendor, phys_attr; u32 phys_data_size, phys_data; - phys_data_size = virt_to_phys(data_size); - phys_vendor = virt_to_phys(vendor); - phys_name = virt_to_phys(name); - phys_attr = virt_to_phys(attr); - phys_data = virt_to_phys(data); + phys_data_size = virt_to_phys_or_null(data_size); + phys_vendor = virt_to_phys_or_null(vendor); + phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); + phys_attr = virt_to_phys_or_null(attr); + phys_data = virt_to_phys_or_null_size(data, *data_size); status = efi_thunk(get_variable, phys_name, phys_vendor, phys_attr, phys_data_size, phys_data); @@ -586,9 +620,9 @@ efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor, u32 phys_name, phys_vendor, phys_data; efi_status_t status; - phys_name = virt_to_phys(name); - phys_vendor = virt_to_phys(vendor); - phys_data = virt_to_phys(data); + phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); + phys_vendor = virt_to_phys_or_null(vendor); + phys_data = virt_to_phys_or_null_size(data, data_size); /* If data_size is > sizeof(u32) we've got problems */ status = efi_thunk(set_variable, phys_name, phys_vendor, @@ -605,9 +639,9 @@ efi_thunk_get_next_variable(unsigned long *name_size, efi_status_t status; u32 phys_name_size, phys_name, phys_vendor; - phys_name_size = virt_to_phys(name_size); - phys_vendor = virt_to_phys(vendor); - phys_name = virt_to_phys(name); + phys_name_size = virt_to_phys_or_null(name_size); + phys_vendor = virt_to_phys_or_null(vendor); + phys_name = virt_to_phys_or_null_size(name, *name_size); status = efi_thunk(get_next_variable, phys_name_size, phys_name, phys_vendor); @@ -621,7 +655,7 @@ efi_thunk_get_next_high_mono_count(u32 *count) efi_status_t status; u32 phys_count; - phys_count = virt_to_phys(count); + phys_count = virt_to_phys_or_null(count); status = efi_thunk(get_next_high_mono_count, phys_count); return status; @@ -633,7 +667,7 @@ efi_thunk_reset_system(int reset_type, efi_status_t status, { u32 phys_data; - phys_data = virt_to_phys(data); + phys_data = virt_to_phys_or_null_size(data, data_size); efi_thunk(reset_system, reset_type, status, data_size, phys_data); } @@ -661,9 +695,9 @@ efi_thunk_query_variable_info(u32 attr, u64 *storage_space, if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) return EFI_UNSUPPORTED; - phys_storage = virt_to_phys(storage_space); - phys_remaining = virt_to_phys(remaining_space); - phys_max = virt_to_phys(max_variable_size); + phys_storage = virt_to_phys_or_null(storage_space); + phys_remaining = virt_to_phys_or_null(remaining_space); + phys_max = virt_to_phys_or_null(max_variable_size); status = efi_thunk(query_variable_info, attr, phys_storage, phys_remaining, phys_max); |