[PATCH] - make sure that EFI variable data size is always 64 bit

[PATCH] - make sure that EFI variable data size is always 64 bit

[Matthew Garrett]

The EFI spec states that the data size of an EFI variable is 64 bits. 
"unsigned long", on the other hand, isn't on IA32.

diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
index bda5bce..488c24c 100644
--- a/drivers/firmware/efivars.c
+++ b/drivers/firmware/efivars.c
@@ -110,7 +110,7 @@ static LIST_HEAD(efivar_list);
 struct efi_variable {
 	efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
 	efi_guid_t    VendorGuid;
-	unsigned long DataSize;
+	__u64	      DataSize;
 	__u8          Data[1024];
 	efi_status_t  Status;
 	__u32         Attributes;
diff --git a/include/linux/efi.h b/include/linux/efi.h
index 9e97bc2..3f0a179 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -163,7 +163,7 @@ typedef efi_status_t efi_get_wakeup_time
 					    efi_time_t *tm);
 typedef efi_status_t efi_set_wakeup_time_t (efi_bool_t enabled, efi_time_t *tm);
 typedef efi_status_t efi_get_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,
-					 unsigned long *data_size, void *data);
+					 __u64 *data_size, void *data);
 typedef efi_status_t efi_get_next_variable_t (unsigned long *name_size, efi_char16_t *name,
 					      efi_guid_t *vendor);
 typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor, 

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: [PATCH] - make sure that EFI variable data size is always 64 bit

[Matt Domsch]

On Sun, Mar 19, 2006 at 06:43:25PM +0000, Matthew Garrett wrote:
> The EFI spec states that the data size of an EFI variable is 64 bits. 
> "unsigned long", on the other hand, isn't on IA32.
> 
> diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
> index bda5bce..488c24c 100644
> --- a/drivers/firmware/efivars.c
> +++ b/drivers/firmware/efivars.c
> @@ -110,7 +110,7 @@ static LIST_HEAD(efivar_list);
>  struct efi_variable {
>  	efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
>  	efi_guid_t    VendorGuid;
> -	unsigned long DataSize;
> +	__u64	      DataSize;
>  	__u8          Data[1024];
>  	efi_status_t  Status;
>  	__u32         Attributes;
> diff --git a/include/linux/efi.h b/include/linux/efi.h
> index 9e97bc2..3f0a179 100644
> --- a/include/linux/efi.h
> +++ b/include/linux/efi.h
> @@ -163,7 +163,7 @@ typedef efi_status_t efi_get_wakeup_time
>  					    efi_time_t *tm);
>  typedef efi_status_t efi_set_wakeup_time_t (efi_bool_t enabled, efi_time_t *tm);
>  typedef efi_status_t efi_get_variable_t (efi_char16_t *name, efi_guid_t *vendor, u32 *attr,
> -					 unsigned long *data_size, void *data);
> +					 __u64 *data_size, void *data);
>  typedef efi_status_t efi_get_next_variable_t (unsigned long *name_size, efi_char16_t *name,
>  					      efi_guid_t *vendor);
>  typedef efi_status_t efi_set_variable_t (efi_char16_t *name, efi_guid_t *vendor, 



NAK.  efibootmgr, the main userspace consumer of this struct, also
thinks this is an "unsigned long".   This wasn't specified up through
EFI 1.10, which I complained about (it, and efi_status_t being defined
as an unsigned long) both force userspace consumers of this struct to
match size of the kernel (i.e. compile a 32-bit binary for 32-bit kernel,
and compile a 64-bit binary for 64-bit kernel).

-Matt


-- 
Matt Domsch
Software Architect
Dell Linux Solutions linux.dell.com & www.dell.com/linux
Linux on Dell mailing lists @ http://lists.us.dell.com

Re: [PATCH] - make sure that EFI variable data size is always 64 bit

[Matthew Garrett]

On Sun, Mar 19, 2006 at 03:29:01PM -0600, Matt Domsch wrote:

> NAK.  efibootmgr, the main userspace consumer of this struct, also
> thinks this is an "unsigned long".

Hm. My copy of efibootmgr has:

typedef struct _efi_variable_t {
        efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
        efi_guid_t    VendorGuid;
        uint64_t         DataSize;
        uint8_t          Data[1024];
        efi_status_t  Status;
        uint32_t         Attributes;
} __attribute__((packed)) efi_variable_t;

which certainly makes it look like it's expecting a 64-bit value. But 
checking the spec does seem to suggest that datasize is a native value, 
so presumably it's an efibootmgr bug rather than a kernel one? In that 
case, this ought to be dropped.

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: [PATCH] - make sure that EFI variable data size is always 64 bit

[Matt Domsch]

On Sun, Mar 19, 2006 at 09:33:01PM +0000, Matthew Garrett wrote:
> On Sun, Mar 19, 2006 at 03:29:01PM -0600, Matt Domsch wrote:
> 
> > NAK.  efibootmgr, the main userspace consumer of this struct, also
> > thinks this is an "unsigned long".
> 
> Hm. My copy of efibootmgr has:
> 
> typedef struct _efi_variable_t {
>         efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
>         efi_guid_t    VendorGuid;
>         uint64_t         DataSize;
>         uint8_t          Data[1024];
>         efi_status_t  Status;
>         uint32_t         Attributes;
> } __attribute__((packed)) efi_variable_t;
> 
> which certainly makes it look like it's expecting a 64-bit value. But 
> checking the spec does seem to suggest that datasize is a native value, 
> so presumably it's an efibootmgr bug rather than a kernel one? In that 
> case, this ought to be dropped.

Sorry, I did mean to post a link to the latest efibootmgr that has
this fixed:

Home page: http://linux.dell.com/efibootmgr/

For distros that care about 32-bit EFI, please upgrade to efibootmgr 0.5.3.
http://linux.dell.com/efibootmgr/efibootmgr-0.5.3.tar.gz
http://linux.dell.com/efibootmgr/efibootmgr-0.5.3.tar.gz.sign
http://linux.dell.com/efibootmgr/ChangeLog

Thanks,
Matt

-- 
Matt Domsch
Software Architect
Dell Linux Solutions linux.dell.com & www.dell.com/linux
Linux on Dell mailing lists @ http://lists.us.dell.com

Re: [PATCH] - make sure that EFI variable data size is always 64 bit

[Matthew Garrett]

On Sun, Mar 19, 2006 at 04:49:40PM -0600, Matt Domsch wrote:

> Sorry, I did mean to post a link to the latest efibootmgr that has
> this fixed:

Thanks - the copy I had was rather older than I thought. Sorry about the 
confusion.

-- 
Matthew Garrett | mjg59@srcf.ucam.org

Re: [PATCH] - make sure that EFI variable data size is always 64 bit

[Pavel Machek]

On Ne 19-03-06 18:43:25, Matthew Garrett wrote:
> The EFI spec states that the data size of an EFI variable is 64 bits. 
> "unsigned long", on the other hand, isn't on IA32.
> 
> diff --git a/drivers/firmware/efivars.c b/drivers/firmware/efivars.c
> index bda5bce..488c24c 100644
> --- a/drivers/firmware/efivars.c
> +++ b/drivers/firmware/efivars.c
> @@ -110,7 +110,7 @@ static LIST_HEAD(efivar_list);
>  struct efi_variable {
>  	efi_char16_t  VariableName[1024/sizeof(efi_char16_t)];
>  	efi_guid_t    VendorGuid;
> -	unsigned long DataSize;
> +	__u64	      DataSize;
>  	__u8          Data[1024];
>  	efi_status_t  Status;
>  	__u32         Attributes;

Please, use u64 (not __u64).

									Pavel

-- 
86:        {