Re: [U-Boot] [PATCH v3] arm: socfpga: mailbox: Fix off-by-one error on command length checking

[Marek Vasut]

On 4/22/19 3:20 AM, Ley Foon Tan wrote:
> On Sun, Apr 21, 2019 at 4:30 PM Marek Vasut  wrote:
>>
>> On 4/19/19 10:52 PM, Simon Goldschmidt wrote:
>>>
>>>
>>> Marek Vasut mailto:ma...@denx.de>> schrieb am Fr., 19.
>>> Apr. 2019, 11:29:
>>>
>>> On 4/19/19 8:17 AM, Ley Foon Tan wrote:
>>> > A mailbox command contains 1-DWORD header + arguments. The "len"
>>> variable
>>> > only contains the length of the arguments, but not the 1-DWORD header.
>>> > Include the length of header when checking the ring buffer space to
>>> > prevent off-by-one error.
>>>
>>> How long is a DWORD ? Windows API (which we have nothing to do with)
>>> defines that as 32bit type, "typedef unsigned long DWORD;", see [1].
>>> But the patch below fixes an off-by-one error , not off by four error ?
>>>
>>>
>>> As all the macros for that mailbox seem to do u32 index access only, I'd
>>> be ok with the commit message if it didn't use the term 'DWORD'...
>>
>> Does that mean MBOX_CMD_BUFFER_SIZE is not in byte units, but in u32 units ?
> Yes, it is in u32 unit. One slot location is u32.
> How about change DWORD to u32 in commit message?

Yes please. It would also make sense to add a comment into the code that
len is not in bytes, but u32 units .

-- 
Best regards,
Marek Vasut
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

Re: [U-Boot] [PATCH v3] arm: socfpga: mailbox: Fix off-by-one error on command length checking

[Ley Foon Tan]

On Sun, Apr 21, 2019 at 4:30 PM Marek Vasut  wrote:
>
> On 4/19/19 10:52 PM, Simon Goldschmidt wrote:
> >
> >
> > Marek Vasut mailto:ma...@denx.de>> schrieb am Fr., 19.
> > Apr. 2019, 11:29:
> >
> > On 4/19/19 8:17 AM, Ley Foon Tan wrote:
> > > A mailbox command contains 1-DWORD header + arguments. The "len"
> > variable
> > > only contains the length of the arguments, but not the 1-DWORD header.
> > > Include the length of header when checking the ring buffer space to
> > > prevent off-by-one error.
> >
> > How long is a DWORD ? Windows API (which we have nothing to do with)
> > defines that as 32bit type, "typedef unsigned long DWORD;", see [1].
> > But the patch below fixes an off-by-one error , not off by four error ?
> >
> >
> > As all the macros for that mailbox seem to do u32 index access only, I'd
> > be ok with the commit message if it didn't use the term 'DWORD'...
>
> Does that mean MBOX_CMD_BUFFER_SIZE is not in byte units, but in u32 units ?
Yes, it is in u32 unit. One slot location is u32.
How about change DWORD to u32 in commit message?


Regards
Ley Foon
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

Re: [U-Boot] [PATCH v3] arm: socfpga: mailbox: Fix off-by-one error on command length checking

[Marek Vasut]

On 4/19/19 10:52 PM, Simon Goldschmidt wrote:
> 
> 
> Marek Vasut mailto:ma...@denx.de>> schrieb am Fr., 19.
> Apr. 2019, 11:29:
> 
> On 4/19/19 8:17 AM, Ley Foon Tan wrote:
> > A mailbox command contains 1-DWORD header + arguments. The "len"
> variable
> > only contains the length of the arguments, but not the 1-DWORD header.
> > Include the length of header when checking the ring buffer space to
> > prevent off-by-one error.
> 
> How long is a DWORD ? Windows API (which we have nothing to do with)
> defines that as 32bit type, "typedef unsigned long DWORD;", see [1].
> But the patch below fixes an off-by-one error , not off by four error ?
> 
> 
> As all the macros for that mailbox seem to do u32 index access only, I'd
> be ok with the commit message if it didn't use the term 'DWORD'...

Does that mean MBOX_CMD_BUFFER_SIZE is not in byte units, but in u32 units ?

> Regards,
> Simon
> 
> 
> [1]
> 
> https://docs.microsoft.com/en-us/windows/desktop/winprog/windows-data-types
> 
> > Signed-off-by: Ley Foon Tan  >
> > Signed-off-by: Chee Hong Ang  >
> > ---
> > v2->v3:
> > - Update commit description.
> > ---
> >  arch/arm/mach-socfpga/mailbox_s10.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/mach-socfpga/mailbox_s10.c
> b/arch/arm/mach-socfpga/mailbox_s10.c
> > index 3c33223936..8363c93e90 100644
> > --- a/arch/arm/mach-socfpga/mailbox_s10.c
> > +++ b/arch/arm/mach-socfpga/mailbox_s10.c
> > @@ -59,7 +59,7 @@ static __always_inline int
> mbox_fill_cmd_circular_buff(u32 header, u32 len,
> >        */
> >       if (((cin + 1) % MBOX_CMD_BUFFER_SIZE) == cout ||
> >           ((MBOX_CMD_BUFFER_SIZE - cin + cout - 1) %
> > -          MBOX_CMD_BUFFER_SIZE) < len)
> > +          MBOX_CMD_BUFFER_SIZE) < (len + 1))
> >               return -ENOMEM;
> > 
> >       /* write header to circular buffer */
> >
> 
> 
> -- 
> Best regards,
> Marek Vasut
> 


-- 
Best regards,
Marek Vasut
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

Re: [U-Boot] [PATCH v3] arm: socfpga: mailbox: Fix off-by-one error on command length checking

[Simon Goldschmidt]

Marek Vasut  schrieb am Fr., 19. Apr. 2019, 11:29:

> On 4/19/19 8:17 AM, Ley Foon Tan wrote:
> > A mailbox command contains 1-DWORD header + arguments. The "len" variable
> > only contains the length of the arguments, but not the 1-DWORD header.
> > Include the length of header when checking the ring buffer space to
> > prevent off-by-one error.
>
> How long is a DWORD ? Windows API (which we have nothing to do with)
> defines that as 32bit type, "typedef unsigned long DWORD;", see [1].
> But the patch below fixes an off-by-one error , not off by four error ?
>

As all the macros for that mailbox seem to do u32 index access only, I'd be
ok with the commit message if it didn't use the term 'DWORD'...

Regards,
Simon


> [1]
> https://docs.microsoft.com/en-us/windows/desktop/winprog/windows-data-types
>
> > Signed-off-by: Ley Foon Tan 
> > Signed-off-by: Chee Hong Ang 
> > ---
> > v2->v3:
> > - Update commit description.
> > ---
> >  arch/arm/mach-socfpga/mailbox_s10.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/arch/arm/mach-socfpga/mailbox_s10.c
> b/arch/arm/mach-socfpga/mailbox_s10.c
> > index 3c33223936..8363c93e90 100644
> > --- a/arch/arm/mach-socfpga/mailbox_s10.c
> > +++ b/arch/arm/mach-socfpga/mailbox_s10.c
> > @@ -59,7 +59,7 @@ static __always_inline int
> mbox_fill_cmd_circular_buff(u32 header, u32 len,
> >*/
> >   if (((cin + 1) % MBOX_CMD_BUFFER_SIZE) == cout ||
> >   ((MBOX_CMD_BUFFER_SIZE - cin + cout - 1) %
> > -  MBOX_CMD_BUFFER_SIZE) < len)
> > +  MBOX_CMD_BUFFER_SIZE) < (len + 1))
> >   return -ENOMEM;
> >
> >   /* write header to circular buffer */
> >
>
>
> --
> Best regards,
> Marek Vasut
>
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

Re: [U-Boot] [PATCH v3] arm: socfpga: mailbox: Fix off-by-one error on command length checking

[Marek Vasut]

On 4/19/19 8:17 AM, Ley Foon Tan wrote:
> A mailbox command contains 1-DWORD header + arguments. The "len" variable
> only contains the length of the arguments, but not the 1-DWORD header.
> Include the length of header when checking the ring buffer space to
> prevent off-by-one error.

How long is a DWORD ? Windows API (which we have nothing to do with)
defines that as 32bit type, "typedef unsigned long DWORD;", see [1].
But the patch below fixes an off-by-one error , not off by four error ?

[1]
https://docs.microsoft.com/en-us/windows/desktop/winprog/windows-data-types

> Signed-off-by: Ley Foon Tan 
> Signed-off-by: Chee Hong Ang 
> ---
> v2->v3:
> - Update commit description.
> ---
>  arch/arm/mach-socfpga/mailbox_s10.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm/mach-socfpga/mailbox_s10.c 
> b/arch/arm/mach-socfpga/mailbox_s10.c
> index 3c33223936..8363c93e90 100644
> --- a/arch/arm/mach-socfpga/mailbox_s10.c
> +++ b/arch/arm/mach-socfpga/mailbox_s10.c
> @@ -59,7 +59,7 @@ static __always_inline int mbox_fill_cmd_circular_buff(u32 
> header, u32 len,
>*/
>   if (((cin + 1) % MBOX_CMD_BUFFER_SIZE) == cout ||
>   ((MBOX_CMD_BUFFER_SIZE - cin + cout - 1) %
> -  MBOX_CMD_BUFFER_SIZE) < len)
> +  MBOX_CMD_BUFFER_SIZE) < (len + 1))
>   return -ENOMEM;
>  
>   /* write header to circular buffer */
> 


-- 
Best regards,
Marek Vasut
___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot

[U-Boot] [PATCH v3] arm: socfpga: mailbox: Fix off-by-one error on command length checking

[Ley Foon Tan]

A mailbox command contains 1-DWORD header + arguments. The "len" variable
only contains the length of the arguments, but not the 1-DWORD header.
Include the length of header when checking the ring buffer space to
prevent off-by-one error.

Signed-off-by: Ley Foon Tan 
Signed-off-by: Chee Hong Ang 
---
v2->v3:
- Update commit description.
---
 arch/arm/mach-socfpga/mailbox_s10.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/mach-socfpga/mailbox_s10.c 
b/arch/arm/mach-socfpga/mailbox_s10.c
index 3c33223936..8363c93e90 100644
--- a/arch/arm/mach-socfpga/mailbox_s10.c
+++ b/arch/arm/mach-socfpga/mailbox_s10.c
@@ -59,7 +59,7 @@ static __always_inline int mbox_fill_cmd_circular_buff(u32 
header, u32 len,
 */
if (((cin + 1) % MBOX_CMD_BUFFER_SIZE) == cout ||
((MBOX_CMD_BUFFER_SIZE - cin + cout - 1) %
-MBOX_CMD_BUFFER_SIZE) < len)
+MBOX_CMD_BUFFER_SIZE) < (len + 1))
return -ENOMEM;
 
/* write header to circular buffer */
-- 
2.19.0

___
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot