Skip to content

Commit

Permalink
Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/l…
Browse files Browse the repository at this point in the history 
…inux/kernel/git/tip/tip

Pull EFI fixes from Ingo Molnar:
 "Three fixes to EFI mixed boot mode, mostly related to x86-64 vmap
  stacks activated years ago, bug-fixed recently for EFI, which had
  knock-on effects of various 1:1 mapping assumptions in mixed mode.

  There's also a READ_ONCE() fix for reading an mmap-ed EFI firmware
  data field only once, out of caution"

* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi: READ_ONCE rng seed size before munmap
  efi/x86: Handle by-ref arguments covering multiple pages in mixed mode
  efi/x86: Remove support for EFI time and counter services in mixed mode
  efi/x86: Align GUIDs to their size in the mixed mode runtime wrapper
  • Loading branch information
Linus Torvalds committed Mar 2, 2020
2 parents 98d54f8 + be36f9e commit e130a92
Show file tree
Hide file tree
Showing 2 changed files with 54 additions and 101 deletions.
151 changes: 52 additions & 99 deletions arch/x86/platform/efi/efi_64.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -180,24 +180,21 @@ void efi_sync_low_kernel_mappings(void)
static inline phys_addr_t
virt_to_phys_or_null_size(void *va, unsigned long size)
{
bool bad_size;
phys_addr_t pa;

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);
pa = slow_virt_to_phys(va);

WARN_ON(!IS_ALIGNED((unsigned long)va, size) || bad_size);
/* check if the object crosses a page boundary */
if (WARN_ON((pa ^ (pa + size - 1)) & PAGE_MASK))
return 0;

return slow_virt_to_phys(va);
return pa;
}

#define virt_to_phys_or_null(addr) \
Expand Down Expand Up @@ -568,85 +565,25 @@ efi_thunk_set_virtual_address_map(unsigned long memory_map_size,

static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc)
{
efi_status_t status;
u32 phys_tm, phys_tc;
unsigned long flags;

spin_lock(&rtc_lock);
spin_lock_irqsave(&efi_runtime_lock, flags);

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);

spin_unlock_irqrestore(&efi_runtime_lock, flags);
spin_unlock(&rtc_lock);

return status;
return EFI_UNSUPPORTED;
}

static efi_status_t efi_thunk_set_time(efi_time_t *tm)
{
efi_status_t status;
u32 phys_tm;
unsigned long flags;

spin_lock(&rtc_lock);
spin_lock_irqsave(&efi_runtime_lock, flags);

phys_tm = virt_to_phys_or_null(tm);

status = efi_thunk(set_time, phys_tm);

spin_unlock_irqrestore(&efi_runtime_lock, flags);
spin_unlock(&rtc_lock);

return status;
return EFI_UNSUPPORTED;
}

static efi_status_t
efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending,
efi_time_t *tm)
{
efi_status_t status;
u32 phys_enabled, phys_pending, phys_tm;
unsigned long flags;

spin_lock(&rtc_lock);
spin_lock_irqsave(&efi_runtime_lock, flags);

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);

spin_unlock_irqrestore(&efi_runtime_lock, flags);
spin_unlock(&rtc_lock);

return status;
return EFI_UNSUPPORTED;
}

static efi_status_t
efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
{
efi_status_t status;
u32 phys_tm;
unsigned long flags;

spin_lock(&rtc_lock);
spin_lock_irqsave(&efi_runtime_lock, flags);

phys_tm = virt_to_phys_or_null(tm);

status = efi_thunk(set_wakeup_time, enabled, phys_tm);

spin_unlock_irqrestore(&efi_runtime_lock, flags);
spin_unlock(&rtc_lock);

return status;
return EFI_UNSUPPORTED;
}

static unsigned long efi_name_size(efi_char16_t *name)
Expand All @@ -658,21 +595,28 @@ static efi_status_t
efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor,
u32 *attr, unsigned long *data_size, void *data)
{
u8 buf[24] __aligned(8);
efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
efi_status_t status;
u32 phys_name, phys_vendor, phys_attr;
u32 phys_data_size, phys_data;
unsigned long flags;

spin_lock_irqsave(&efi_runtime_lock, flags);

*vnd = *vendor;

phys_data_size = virt_to_phys_or_null(data_size);
phys_vendor = virt_to_phys_or_null(vendor);
phys_vendor = virt_to_phys_or_null(vnd);
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);
if (!phys_name || (data && !phys_data))
status = EFI_INVALID_PARAMETER;
else
status = efi_thunk(get_variable, phys_name, phys_vendor,
phys_attr, phys_data_size, phys_data);

spin_unlock_irqrestore(&efi_runtime_lock, flags);

Expand All @@ -683,19 +627,25 @@ static efi_status_t
efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor,
u32 attr, unsigned long data_size, void *data)
{
u8 buf[24] __aligned(8);
efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
u32 phys_name, phys_vendor, phys_data;
efi_status_t status;
unsigned long flags;

spin_lock_irqsave(&efi_runtime_lock, flags);

*vnd = *vendor;

phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
phys_vendor = virt_to_phys_or_null(vendor);
phys_vendor = virt_to_phys_or_null(vnd);
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,
attr, data_size, phys_data);
if (!phys_name || !phys_data)
status = EFI_INVALID_PARAMETER;
else
status = efi_thunk(set_variable, phys_name, phys_vendor,
attr, data_size, phys_data);

spin_unlock_irqrestore(&efi_runtime_lock, flags);

Expand All @@ -707,20 +657,26 @@ efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
u32 attr, unsigned long data_size,
void *data)
{
u8 buf[24] __aligned(8);
efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
u32 phys_name, phys_vendor, phys_data;
efi_status_t status;
unsigned long flags;

if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
return EFI_NOT_READY;

*vnd = *vendor;

phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
phys_vendor = virt_to_phys_or_null(vendor);
phys_vendor = virt_to_phys_or_null(vnd);
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,
attr, data_size, phys_data);
if (!phys_name || !phys_data)
status = EFI_INVALID_PARAMETER;
else
status = efi_thunk(set_variable, phys_name, phys_vendor,
attr, data_size, phys_data);

spin_unlock_irqrestore(&efi_runtime_lock, flags);

Expand All @@ -732,39 +688,36 @@ efi_thunk_get_next_variable(unsigned long *name_size,
efi_char16_t *name,
efi_guid_t *vendor)
{
u8 buf[24] __aligned(8);
efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
efi_status_t status;
u32 phys_name_size, phys_name, phys_vendor;
unsigned long flags;

spin_lock_irqsave(&efi_runtime_lock, flags);

*vnd = *vendor;

phys_name_size = virt_to_phys_or_null(name_size);
phys_vendor = virt_to_phys_or_null(vendor);
phys_vendor = virt_to_phys_or_null(vnd);
phys_name = virt_to_phys_or_null_size(name, *name_size);

status = efi_thunk(get_next_variable, phys_name_size,
phys_name, phys_vendor);
if (!phys_name)
status = EFI_INVALID_PARAMETER;
else
status = efi_thunk(get_next_variable, phys_name_size,
phys_name, phys_vendor);

spin_unlock_irqrestore(&efi_runtime_lock, flags);

*vendor = *vnd;
return status;
}

static efi_status_t
efi_thunk_get_next_high_mono_count(u32 *count)
{
efi_status_t status;
u32 phys_count;
unsigned long flags;

spin_lock_irqsave(&efi_runtime_lock, flags);

phys_count = virt_to_phys_or_null(count);
status = efi_thunk(get_next_high_mono_count, phys_count);

spin_unlock_irqrestore(&efi_runtime_lock, flags);

return status;
return EFI_UNSUPPORTED;
}

static void
Expand Down
4 changes: 2 additions & 2 deletions drivers/firmware/efi/efi.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -552,7 +552,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,

seed = early_memremap(efi.rng_seed, sizeof(*seed));
if (seed != NULL) {
size = seed->size;
size = READ_ONCE(seed->size);
early_memunmap(seed, sizeof(*seed));
} else {
pr_err("Could not map UEFI random seed!\n");
Expand All @@ -562,7 +562,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
sizeof(*seed) + size);
if (seed != NULL) {
pr_notice("seeding entropy pool\n");
add_bootloader_randomness(seed->bits, seed->size);
add_bootloader_randomness(seed->bits, size);
early_memunmap(seed, sizeof(*seed) + size);
} else {
pr_err("Could not map UEFI random seed!\n");
Expand Down

0 comments on commit e130a92

Please sign in to comment.