Re: [PATCH v2] rave-sp: Remove VLA

[Kees Cook]

On Mon, Apr 30, 2018 at 5:38 AM, Lee Jones  wrote:
> On Fri, 27 Apr 2018, Kyle Spiers wrote:
>
>> As part of the effort to remove VLAs from the kernel[1], this creates
>> constants for the checksum lengths of CCITT and 8B2C and changes
>> crc_calculated to be the maximum size of a checksum.
>>
>> https://lkml.org/lkml/2018/3/7/621
>>
>> Signed-off-by: Kyle Spiers 
>> ---
>>  drivers/mfd/rave-sp.c | 11 +--
>>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> Applied, thanks.
>
> Kees, do you want me to add your Ack?

Sure!

Reviewed-by: Kees Cook 

Thanks!

-Kees

>
>> diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c
>> index 5c858e784a89..4ce96b7137db 100644
>> --- a/drivers/mfd/rave-sp.c
>> +++ b/drivers/mfd/rave-sp.c
>> @@ -45,7 +45,9 @@
>>  #define RAVE_SP_DLE  0x10
>>
>>  #define RAVE_SP_MAX_DATA_SIZE64
>> -#define RAVE_SP_CHECKSUM_SIZE2  /* Worst case scenario on 
>> RDU2 */
>> +#define RAVE_SP_CHECKSUM_8B2C1
>> +#define RAVE_SP_CHECKSUM_CCITT   2
>> +#define RAVE_SP_CHECKSUM_SIZERAVE_SP_CHECKSUM_CCITT
>>  /*
>>   * We don't store STX, ETX and unescaped bytes, so Rx is only
>>   * DATA + CSUM
>> @@ -415,7 +417,12 @@ static void rave_sp_receive_frame(struct rave_sp *sp,
>>   const size_t payload_length  = length - checksum_length;
>>   const u8 *crc_reported   = [payload_length];
>>   struct device *dev   = >serdev->dev;
>> - u8 crc_calculated[checksum_length];
>> + u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
>> +
>> + if (unlikely(checksum_length > sizeof(crc_calculated))) {
>> + dev_warn(dev, "Checksum too long, dropping\n");
>> + return;
>> + }
>>
>>   print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE,
>>  16, 1, data, length, false);
>
> --
> Lee Jones [李琼斯]
> Linaro Services Technical Lead
> Linaro.org │ Open source software for ARM SoCs
> Follow Linaro: Facebook | Twitter | Blog



-- 
Kees Cook
Pixel Security

Re: [PATCH v2] rave-sp: Remove VLA

[Kees Cook]

On Mon, Apr 30, 2018 at 5:38 AM, Lee Jones  wrote:
> On Fri, 27 Apr 2018, Kyle Spiers wrote:
>
>> As part of the effort to remove VLAs from the kernel[1], this creates
>> constants for the checksum lengths of CCITT and 8B2C and changes
>> crc_calculated to be the maximum size of a checksum.
>>
>> https://lkml.org/lkml/2018/3/7/621
>>
>> Signed-off-by: Kyle Spiers 
>> ---
>>  drivers/mfd/rave-sp.c | 11 +--
>>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> Applied, thanks.
>
> Kees, do you want me to add your Ack?

Sure!

Reviewed-by: Kees Cook 

Thanks!

-Kees

>
>> diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c
>> index 5c858e784a89..4ce96b7137db 100644
>> --- a/drivers/mfd/rave-sp.c
>> +++ b/drivers/mfd/rave-sp.c
>> @@ -45,7 +45,9 @@
>>  #define RAVE_SP_DLE  0x10
>>
>>  #define RAVE_SP_MAX_DATA_SIZE64
>> -#define RAVE_SP_CHECKSUM_SIZE2  /* Worst case scenario on 
>> RDU2 */
>> +#define RAVE_SP_CHECKSUM_8B2C1
>> +#define RAVE_SP_CHECKSUM_CCITT   2
>> +#define RAVE_SP_CHECKSUM_SIZERAVE_SP_CHECKSUM_CCITT
>>  /*
>>   * We don't store STX, ETX and unescaped bytes, so Rx is only
>>   * DATA + CSUM
>> @@ -415,7 +417,12 @@ static void rave_sp_receive_frame(struct rave_sp *sp,
>>   const size_t payload_length  = length - checksum_length;
>>   const u8 *crc_reported   = [payload_length];
>>   struct device *dev   = >serdev->dev;
>> - u8 crc_calculated[checksum_length];
>> + u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
>> +
>> + if (unlikely(checksum_length > sizeof(crc_calculated))) {
>> + dev_warn(dev, "Checksum too long, dropping\n");
>> + return;
>> + }
>>
>>   print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE,
>>  16, 1, data, length, false);
>
> --
> Lee Jones [李琼斯]
> Linaro Services Technical Lead
> Linaro.org │ Open source software for ARM SoCs
> Follow Linaro: Facebook | Twitter | Blog



-- 
Kees Cook
Pixel Security

Re: [PATCH v2] rave-sp: Remove VLA

[Lee Jones]

On Fri, 27 Apr 2018, Kyle Spiers wrote:

> As part of the effort to remove VLAs from the kernel[1], this creates
> constants for the checksum lengths of CCITT and 8B2C and changes
> crc_calculated to be the maximum size of a checksum.
> 
> https://lkml.org/lkml/2018/3/7/621
> 
> Signed-off-by: Kyle Spiers 
> ---
>  drivers/mfd/rave-sp.c | 11 +--
>  1 file changed, 9 insertions(+), 2 deletions(-)

Applied, thanks.

Kees, do you want me to add your Ack?

> diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c
> index 5c858e784a89..4ce96b7137db 100644
> --- a/drivers/mfd/rave-sp.c
> +++ b/drivers/mfd/rave-sp.c
> @@ -45,7 +45,9 @@
>  #define RAVE_SP_DLE  0x10
>  
>  #define RAVE_SP_MAX_DATA_SIZE64
> -#define RAVE_SP_CHECKSUM_SIZE2  /* Worst case scenario on 
> RDU2 */
> +#define RAVE_SP_CHECKSUM_8B2C1
> +#define RAVE_SP_CHECKSUM_CCITT   2
> +#define RAVE_SP_CHECKSUM_SIZERAVE_SP_CHECKSUM_CCITT
>  /*
>   * We don't store STX, ETX and unescaped bytes, so Rx is only
>   * DATA + CSUM
> @@ -415,7 +417,12 @@ static void rave_sp_receive_frame(struct rave_sp *sp,
>   const size_t payload_length  = length - checksum_length;
>   const u8 *crc_reported   = [payload_length];
>   struct device *dev   = >serdev->dev;
> - u8 crc_calculated[checksum_length];
> + u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
> +
> + if (unlikely(checksum_length > sizeof(crc_calculated))) {
> + dev_warn(dev, "Checksum too long, dropping\n");
> + return;
> + }
>  
>   print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE,
>  16, 1, data, length, false);

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

Re: [PATCH v2] rave-sp: Remove VLA

[Lee Jones]

On Fri, 27 Apr 2018, Kyle Spiers wrote:

> As part of the effort to remove VLAs from the kernel[1], this creates
> constants for the checksum lengths of CCITT and 8B2C and changes
> crc_calculated to be the maximum size of a checksum.
> 
> https://lkml.org/lkml/2018/3/7/621
> 
> Signed-off-by: Kyle Spiers 
> ---
>  drivers/mfd/rave-sp.c | 11 +--
>  1 file changed, 9 insertions(+), 2 deletions(-)

Applied, thanks.

Kees, do you want me to add your Ack?

> diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c
> index 5c858e784a89..4ce96b7137db 100644
> --- a/drivers/mfd/rave-sp.c
> +++ b/drivers/mfd/rave-sp.c
> @@ -45,7 +45,9 @@
>  #define RAVE_SP_DLE  0x10
>  
>  #define RAVE_SP_MAX_DATA_SIZE64
> -#define RAVE_SP_CHECKSUM_SIZE2  /* Worst case scenario on 
> RDU2 */
> +#define RAVE_SP_CHECKSUM_8B2C1
> +#define RAVE_SP_CHECKSUM_CCITT   2
> +#define RAVE_SP_CHECKSUM_SIZERAVE_SP_CHECKSUM_CCITT
>  /*
>   * We don't store STX, ETX and unescaped bytes, so Rx is only
>   * DATA + CSUM
> @@ -415,7 +417,12 @@ static void rave_sp_receive_frame(struct rave_sp *sp,
>   const size_t payload_length  = length - checksum_length;
>   const u8 *crc_reported   = [payload_length];
>   struct device *dev   = >serdev->dev;
> - u8 crc_calculated[checksum_length];
> + u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
> +
> + if (unlikely(checksum_length > sizeof(crc_calculated))) {
> + dev_warn(dev, "Checksum too long, dropping\n");
> + return;
> + }
>  
>   print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE,
>  16, 1, data, length, false);

-- 
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog

[PATCH v2] rave-sp: Remove VLA

[Kyle Spiers]

As part of the effort to remove VLAs from the kernel[1], this creates
constants for the checksum lengths of CCITT and 8B2C and changes
crc_calculated to be the maximum size of a checksum.

https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Kyle Spiers 
---
 drivers/mfd/rave-sp.c | 11 +--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c
index 5c858e784a89..4ce96b7137db 100644
--- a/drivers/mfd/rave-sp.c
+++ b/drivers/mfd/rave-sp.c
@@ -45,7 +45,9 @@
 #define RAVE_SP_DLE0x10
 
 #define RAVE_SP_MAX_DATA_SIZE  64
-#define RAVE_SP_CHECKSUM_SIZE  2  /* Worst case scenario on RDU2 */
+#define RAVE_SP_CHECKSUM_8B2C  1
+#define RAVE_SP_CHECKSUM_CCITT 2
+#define RAVE_SP_CHECKSUM_SIZE  RAVE_SP_CHECKSUM_CCITT
 /*
  * We don't store STX, ETX and unescaped bytes, so Rx is only
  * DATA + CSUM
@@ -415,7 +417,12 @@ static void rave_sp_receive_frame(struct rave_sp *sp,
const size_t payload_length  = length - checksum_length;
const u8 *crc_reported   = [payload_length];
struct device *dev   = >serdev->dev;
-   u8 crc_calculated[checksum_length];
+   u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
+
+   if (unlikely(checksum_length > sizeof(crc_calculated))) {
+   dev_warn(dev, "Checksum too long, dropping\n");
+   return;
+   }
 
print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE,
   16, 1, data, length, false);
-- 
2.17.0.441.gb46fe60e1d-goog

[PATCH v2] rave-sp: Remove VLA

[Kyle Spiers]

As part of the effort to remove VLAs from the kernel[1], this creates
constants for the checksum lengths of CCITT and 8B2C and changes
crc_calculated to be the maximum size of a checksum.

https://lkml.org/lkml/2018/3/7/621

Signed-off-by: Kyle Spiers 
---
 drivers/mfd/rave-sp.c | 11 +--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/rave-sp.c b/drivers/mfd/rave-sp.c
index 5c858e784a89..4ce96b7137db 100644
--- a/drivers/mfd/rave-sp.c
+++ b/drivers/mfd/rave-sp.c
@@ -45,7 +45,9 @@
 #define RAVE_SP_DLE0x10
 
 #define RAVE_SP_MAX_DATA_SIZE  64
-#define RAVE_SP_CHECKSUM_SIZE  2  /* Worst case scenario on RDU2 */
+#define RAVE_SP_CHECKSUM_8B2C  1
+#define RAVE_SP_CHECKSUM_CCITT 2
+#define RAVE_SP_CHECKSUM_SIZE  RAVE_SP_CHECKSUM_CCITT
 /*
  * We don't store STX, ETX and unescaped bytes, so Rx is only
  * DATA + CSUM
@@ -415,7 +417,12 @@ static void rave_sp_receive_frame(struct rave_sp *sp,
const size_t payload_length  = length - checksum_length;
const u8 *crc_reported   = [payload_length];
struct device *dev   = >serdev->dev;
-   u8 crc_calculated[checksum_length];
+   u8 crc_calculated[RAVE_SP_CHECKSUM_SIZE];
+
+   if (unlikely(checksum_length > sizeof(crc_calculated))) {
+   dev_warn(dev, "Checksum too long, dropping\n");
+   return;
+   }
 
print_hex_dump(KERN_DEBUG, "rave-sp rx: ", DUMP_PREFIX_NONE,
   16, 1, data, length, false);
-- 
2.17.0.441.gb46fe60e1d-goog