Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Baoquan He]

On 03/15/17 at 02:13pm, Baoquan He wrote:
> PING!
> 
> Is there any suggestion for this code bug fix?
> 
> Boris added comment in patch 1/2 thread that it can also be fixed by
> swapping the naming - EFI_VA_START and EFI_VA_END. As he said the
> swapping can remove the confusion about the naming, while the con is
> changing it now could confuse more people who have the current
> mental picture of the mapping direction.

If swapping the naming is suggested, I can post v2 to change efi code.
Both of them is fine to me.

> 
> And there's also a well known similar use case, stack, like stack_end
> naming in arch/x86/boot/main.c which is the low addr boundary of stack
> region.
> 
> Any idea?
> 
> Thanks
> Baoquan
> 
> On 03/08/17 at 03:47pm, Baoquan He wrote:
> > EFI allocates runtime services regions top-down, starting from EFI_VA_START
> > to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
> > EFI region. The upper boundary of memory regions randomized by KASLR should
> > be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
> > 
> > Correct it in this patch.
> > 
> > Signed-off-by: Baoquan He 
> > ---
> >  arch/x86/mm/kaslr.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
> > index 887e571..aed2064 100644
> > --- a/arch/x86/mm/kaslr.c
> > +++ b/arch/x86/mm/kaslr.c
> > @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = 
> > __PAGE_OFFSET_BASE;
> >  #if defined(CONFIG_X86_ESPFIX64)
> >  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
> >  #elif defined(CONFIG_EFI)
> > -static const unsigned long vaddr_end = EFI_VA_START;
> > +static const unsigned long vaddr_end = EFI_VA_END;
> >  #else
> >  static const unsigned long vaddr_end = __START_KERNEL_map;
> >  #endif
> > @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
> >  */
> > BUILD_BUG_ON(vaddr_start >= vaddr_end);
> > BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
> > -vaddr_end >= EFI_VA_START);
> > +vaddr_end >= EFI_VA_END);
> > BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
> >   IS_ENABLED(CONFIG_EFI)) &&
> >  vaddr_end >= __START_KERNEL_map);
> > -- 
> > 2.5.5
> > 

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Baoquan He]

On 03/15/17 at 02:13pm, Baoquan He wrote:
> PING!
> 
> Is there any suggestion for this code bug fix?
> 
> Boris added comment in patch 1/2 thread that it can also be fixed by
> swapping the naming - EFI_VA_START and EFI_VA_END. As he said the
> swapping can remove the confusion about the naming, while the con is
> changing it now could confuse more people who have the current
> mental picture of the mapping direction.

If swapping the naming is suggested, I can post v2 to change efi code.
Both of them is fine to me.

> 
> And there's also a well known similar use case, stack, like stack_end
> naming in arch/x86/boot/main.c which is the low addr boundary of stack
> region.
> 
> Any idea?
> 
> Thanks
> Baoquan
> 
> On 03/08/17 at 03:47pm, Baoquan He wrote:
> > EFI allocates runtime services regions top-down, starting from EFI_VA_START
> > to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
> > EFI region. The upper boundary of memory regions randomized by KASLR should
> > be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
> > 
> > Correct it in this patch.
> > 
> > Signed-off-by: Baoquan He 
> > ---
> >  arch/x86/mm/kaslr.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
> > index 887e571..aed2064 100644
> > --- a/arch/x86/mm/kaslr.c
> > +++ b/arch/x86/mm/kaslr.c
> > @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = 
> > __PAGE_OFFSET_BASE;
> >  #if defined(CONFIG_X86_ESPFIX64)
> >  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
> >  #elif defined(CONFIG_EFI)
> > -static const unsigned long vaddr_end = EFI_VA_START;
> > +static const unsigned long vaddr_end = EFI_VA_END;
> >  #else
> >  static const unsigned long vaddr_end = __START_KERNEL_map;
> >  #endif
> > @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
> >  */
> > BUILD_BUG_ON(vaddr_start >= vaddr_end);
> > BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
> > -vaddr_end >= EFI_VA_START);
> > +vaddr_end >= EFI_VA_END);
> > BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
> >   IS_ENABLED(CONFIG_EFI)) &&
> >  vaddr_end >= __START_KERNEL_map);
> > -- 
> > 2.5.5
> > 

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Baoquan He]

PING!

Is there any suggestion for this code bug fix?

Boris added comment in patch 1/2 thread that it can also be fixed by
swapping the naming - EFI_VA_START and EFI_VA_END. As he said the
swapping can remove the confusion about the naming, while the con is
changing it now could confuse more people who have the current
mental picture of the mapping direction.

And there's also a well known similar use case, stack, like stack_end
naming in arch/x86/boot/main.c which is the low addr boundary of stack
region.

Any idea?

Thanks
Baoquan

On 03/08/17 at 03:47pm, Baoquan He wrote:
> EFI allocates runtime services regions top-down, starting from EFI_VA_START
> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
> EFI region. The upper boundary of memory regions randomized by KASLR should
> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
> 
> Correct it in this patch.
> 
> Signed-off-by: Baoquan He 
> ---
>  arch/x86/mm/kaslr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
> index 887e571..aed2064 100644
> --- a/arch/x86/mm/kaslr.c
> +++ b/arch/x86/mm/kaslr.c
> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
>  #if defined(CONFIG_X86_ESPFIX64)
>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>  #elif defined(CONFIG_EFI)
> -static const unsigned long vaddr_end = EFI_VA_START;
> +static const unsigned long vaddr_end = EFI_VA_END;
>  #else
>  static const unsigned long vaddr_end = __START_KERNEL_map;
>  #endif
> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>*/
>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
> -  vaddr_end >= EFI_VA_START);
> +  vaddr_end >= EFI_VA_END);
>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
> IS_ENABLED(CONFIG_EFI)) &&
>vaddr_end >= __START_KERNEL_map);
> -- 
> 2.5.5
> 

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Baoquan He]

PING!

Is there any suggestion for this code bug fix?

Boris added comment in patch 1/2 thread that it can also be fixed by
swapping the naming - EFI_VA_START and EFI_VA_END. As he said the
swapping can remove the confusion about the naming, while the con is
changing it now could confuse more people who have the current
mental picture of the mapping direction.

And there's also a well known similar use case, stack, like stack_end
naming in arch/x86/boot/main.c which is the low addr boundary of stack
region.

Any idea?

Thanks
Baoquan

On 03/08/17 at 03:47pm, Baoquan He wrote:
> EFI allocates runtime services regions top-down, starting from EFI_VA_START
> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
> EFI region. The upper boundary of memory regions randomized by KASLR should
> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
> 
> Correct it in this patch.
> 
> Signed-off-by: Baoquan He 
> ---
>  arch/x86/mm/kaslr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
> index 887e571..aed2064 100644
> --- a/arch/x86/mm/kaslr.c
> +++ b/arch/x86/mm/kaslr.c
> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
>  #if defined(CONFIG_X86_ESPFIX64)
>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>  #elif defined(CONFIG_EFI)
> -static const unsigned long vaddr_end = EFI_VA_START;
> +static const unsigned long vaddr_end = EFI_VA_END;
>  #else
>  static const unsigned long vaddr_end = __START_KERNEL_map;
>  #endif
> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>*/
>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
> -  vaddr_end >= EFI_VA_START);
> +  vaddr_end >= EFI_VA_END);
>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
> IS_ENABLED(CONFIG_EFI)) &&
>vaddr_end >= __START_KERNEL_map);
> -- 
> 2.5.5
> 

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Thomas Garnier]

Thanks for the change.

Acked-by: Thomas Garnier 

On Wed, Mar 8, 2017 at 12:35 AM, Bhupesh Sharma  wrote:
> On Wed, Mar 8, 2017 at 1:48 PM, Dave Young  wrote:
>> On 03/08/17 at 03:47pm, Baoquan He wrote:
>>> EFI allocates runtime services regions top-down, starting from EFI_VA_START
>>> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
>>> EFI region. The upper boundary of memory regions randomized by KASLR should
>>> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
>>>
>>> Correct it in this patch.
>>>
>>> Signed-off-by: Baoquan He 
>>> ---
>>>  arch/x86/mm/kaslr.c | 4 ++--
>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
>>> index 887e571..aed2064 100644
>>> --- a/arch/x86/mm/kaslr.c
>>> +++ b/arch/x86/mm/kaslr.c
>>> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = 
>>> __PAGE_OFFSET_BASE;
>>>  #if defined(CONFIG_X86_ESPFIX64)
>>>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>>>  #elif defined(CONFIG_EFI)
>>> -static const unsigned long vaddr_end = EFI_VA_START;
>>> +static const unsigned long vaddr_end = EFI_VA_END;
>>>  #else
>>>  static const unsigned long vaddr_end = __START_KERNEL_map;
>>>  #endif
>>> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>>>*/
>>>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>>>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
>>> -  vaddr_end >= EFI_VA_START);
>>> +  vaddr_end >= EFI_VA_END);
>>>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
>>> IS_ENABLED(CONFIG_EFI)) &&
>>>vaddr_end >= __START_KERNEL_map);
>>> --
>>> 2.5.5
>>>
>>
>> Acked-by: Dave Young 
>>
>
> Thanks Bao for this fix. This makes the KASLR code consistent with
> Address space markers hints in [1]
>
> [1] http://lxr.free-electrons.com/source/arch/x86/mm/dump_pagetables.c#L82
>
> Reviewed-by: Bhupesh Sharma 
>
> Regards,
> Bhupesh



-- 
Thomas

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Thomas Garnier]

Thanks for the change.

Acked-by: Thomas Garnier 

On Wed, Mar 8, 2017 at 12:35 AM, Bhupesh Sharma  wrote:
> On Wed, Mar 8, 2017 at 1:48 PM, Dave Young  wrote:
>> On 03/08/17 at 03:47pm, Baoquan He wrote:
>>> EFI allocates runtime services regions top-down, starting from EFI_VA_START
>>> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
>>> EFI region. The upper boundary of memory regions randomized by KASLR should
>>> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
>>>
>>> Correct it in this patch.
>>>
>>> Signed-off-by: Baoquan He 
>>> ---
>>>  arch/x86/mm/kaslr.c | 4 ++--
>>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
>>> index 887e571..aed2064 100644
>>> --- a/arch/x86/mm/kaslr.c
>>> +++ b/arch/x86/mm/kaslr.c
>>> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = 
>>> __PAGE_OFFSET_BASE;
>>>  #if defined(CONFIG_X86_ESPFIX64)
>>>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>>>  #elif defined(CONFIG_EFI)
>>> -static const unsigned long vaddr_end = EFI_VA_START;
>>> +static const unsigned long vaddr_end = EFI_VA_END;
>>>  #else
>>>  static const unsigned long vaddr_end = __START_KERNEL_map;
>>>  #endif
>>> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>>>*/
>>>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>>>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
>>> -  vaddr_end >= EFI_VA_START);
>>> +  vaddr_end >= EFI_VA_END);
>>>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
>>> IS_ENABLED(CONFIG_EFI)) &&
>>>vaddr_end >= __START_KERNEL_map);
>>> --
>>> 2.5.5
>>>
>>
>> Acked-by: Dave Young 
>>
>
> Thanks Bao for this fix. This makes the KASLR code consistent with
> Address space markers hints in [1]
>
> [1] http://lxr.free-electrons.com/source/arch/x86/mm/dump_pagetables.c#L82
>
> Reviewed-by: Bhupesh Sharma 
>
> Regards,
> Bhupesh



-- 
Thomas

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Bhupesh Sharma]

On Wed, Mar 8, 2017 at 1:48 PM, Dave Young  wrote:
> On 03/08/17 at 03:47pm, Baoquan He wrote:
>> EFI allocates runtime services regions top-down, starting from EFI_VA_START
>> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
>> EFI region. The upper boundary of memory regions randomized by KASLR should
>> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
>>
>> Correct it in this patch.
>>
>> Signed-off-by: Baoquan He 
>> ---
>>  arch/x86/mm/kaslr.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
>> index 887e571..aed2064 100644
>> --- a/arch/x86/mm/kaslr.c
>> +++ b/arch/x86/mm/kaslr.c
>> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = 
>> __PAGE_OFFSET_BASE;
>>  #if defined(CONFIG_X86_ESPFIX64)
>>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>>  #elif defined(CONFIG_EFI)
>> -static const unsigned long vaddr_end = EFI_VA_START;
>> +static const unsigned long vaddr_end = EFI_VA_END;
>>  #else
>>  static const unsigned long vaddr_end = __START_KERNEL_map;
>>  #endif
>> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>>*/
>>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
>> -  vaddr_end >= EFI_VA_START);
>> +  vaddr_end >= EFI_VA_END);
>>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
>> IS_ENABLED(CONFIG_EFI)) &&
>>vaddr_end >= __START_KERNEL_map);
>> --
>> 2.5.5
>>
>
> Acked-by: Dave Young 
>

Thanks Bao for this fix. This makes the KASLR code consistent with
Address space markers hints in [1]

[1] http://lxr.free-electrons.com/source/arch/x86/mm/dump_pagetables.c#L82

Reviewed-by: Bhupesh Sharma 

Regards,
Bhupesh

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Bhupesh Sharma]

On Wed, Mar 8, 2017 at 1:48 PM, Dave Young  wrote:
> On 03/08/17 at 03:47pm, Baoquan He wrote:
>> EFI allocates runtime services regions top-down, starting from EFI_VA_START
>> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
>> EFI region. The upper boundary of memory regions randomized by KASLR should
>> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
>>
>> Correct it in this patch.
>>
>> Signed-off-by: Baoquan He 
>> ---
>>  arch/x86/mm/kaslr.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
>> index 887e571..aed2064 100644
>> --- a/arch/x86/mm/kaslr.c
>> +++ b/arch/x86/mm/kaslr.c
>> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = 
>> __PAGE_OFFSET_BASE;
>>  #if defined(CONFIG_X86_ESPFIX64)
>>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>>  #elif defined(CONFIG_EFI)
>> -static const unsigned long vaddr_end = EFI_VA_START;
>> +static const unsigned long vaddr_end = EFI_VA_END;
>>  #else
>>  static const unsigned long vaddr_end = __START_KERNEL_map;
>>  #endif
>> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>>*/
>>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
>> -  vaddr_end >= EFI_VA_START);
>> +  vaddr_end >= EFI_VA_END);
>>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
>> IS_ENABLED(CONFIG_EFI)) &&
>>vaddr_end >= __START_KERNEL_map);
>> --
>> 2.5.5
>>
>
> Acked-by: Dave Young 
>

Thanks Bao for this fix. This makes the KASLR code consistent with
Address space markers hints in [1]

[1] http://lxr.free-electrons.com/source/arch/x86/mm/dump_pagetables.c#L82

Reviewed-by: Bhupesh Sharma 

Regards,
Bhupesh

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Dave Young]

On 03/08/17 at 03:47pm, Baoquan He wrote:
> EFI allocates runtime services regions top-down, starting from EFI_VA_START
> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
> EFI region. The upper boundary of memory regions randomized by KASLR should
> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
> 
> Correct it in this patch.
> 
> Signed-off-by: Baoquan He 
> ---
>  arch/x86/mm/kaslr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
> index 887e571..aed2064 100644
> --- a/arch/x86/mm/kaslr.c
> +++ b/arch/x86/mm/kaslr.c
> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
>  #if defined(CONFIG_X86_ESPFIX64)
>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>  #elif defined(CONFIG_EFI)
> -static const unsigned long vaddr_end = EFI_VA_START;
> +static const unsigned long vaddr_end = EFI_VA_END;
>  #else
>  static const unsigned long vaddr_end = __START_KERNEL_map;
>  #endif
> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>*/
>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
> -  vaddr_end >= EFI_VA_START);
> +  vaddr_end >= EFI_VA_END);
>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
> IS_ENABLED(CONFIG_EFI)) &&
>vaddr_end >= __START_KERNEL_map);
> -- 
> 2.5.5
> 

Acked-by: Dave Young 

Thanks
Dave

Re: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Dave Young]

On 03/08/17 at 03:47pm, Baoquan He wrote:
> EFI allocates runtime services regions top-down, starting from EFI_VA_START
> to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
> EFI region. The upper boundary of memory regions randomized by KASLR should
> be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.
> 
> Correct it in this patch.
> 
> Signed-off-by: Baoquan He 
> ---
>  arch/x86/mm/kaslr.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
> index 887e571..aed2064 100644
> --- a/arch/x86/mm/kaslr.c
> +++ b/arch/x86/mm/kaslr.c
> @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
>  #if defined(CONFIG_X86_ESPFIX64)
>  static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
>  #elif defined(CONFIG_EFI)
> -static const unsigned long vaddr_end = EFI_VA_START;
> +static const unsigned long vaddr_end = EFI_VA_END;
>  #else
>  static const unsigned long vaddr_end = __START_KERNEL_map;
>  #endif
> @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
>*/
>   BUILD_BUG_ON(vaddr_start >= vaddr_end);
>   BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
> -  vaddr_end >= EFI_VA_START);
> +  vaddr_end >= EFI_VA_END);
>   BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
> IS_ENABLED(CONFIG_EFI)) &&
>vaddr_end >= __START_KERNEL_map);
> -- 
> 2.5.5
> 

Acked-by: Dave Young 

Thanks
Dave

[PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Baoquan He]

EFI allocates runtime services regions top-down, starting from EFI_VA_START
to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
EFI region. The upper boundary of memory regions randomized by KASLR should
be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.

Correct it in this patch.

Signed-off-by: Baoquan He 
---
 arch/x86/mm/kaslr.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index 887e571..aed2064 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
 #if defined(CONFIG_X86_ESPFIX64)
 static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
 #elif defined(CONFIG_EFI)
-static const unsigned long vaddr_end = EFI_VA_START;
+static const unsigned long vaddr_end = EFI_VA_END;
 #else
 static const unsigned long vaddr_end = __START_KERNEL_map;
 #endif
@@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
 */
BUILD_BUG_ON(vaddr_start >= vaddr_end);
BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
-vaddr_end >= EFI_VA_START);
+vaddr_end >= EFI_VA_END);
BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
  IS_ENABLED(CONFIG_EFI)) &&
 vaddr_end >= __START_KERNEL_map);
-- 
2.5.5

[PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI

[Baoquan He]

EFI allocates runtime services regions top-down, starting from EFI_VA_START
to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of
EFI region. The upper boundary of memory regions randomized by KASLR should
be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START.

Correct it in this patch.

Signed-off-by: Baoquan He 
---
 arch/x86/mm/kaslr.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c
index 887e571..aed2064 100644
--- a/arch/x86/mm/kaslr.c
+++ b/arch/x86/mm/kaslr.c
@@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE;
 #if defined(CONFIG_X86_ESPFIX64)
 static const unsigned long vaddr_end = ESPFIX_BASE_ADDR;
 #elif defined(CONFIG_EFI)
-static const unsigned long vaddr_end = EFI_VA_START;
+static const unsigned long vaddr_end = EFI_VA_END;
 #else
 static const unsigned long vaddr_end = __START_KERNEL_map;
 #endif
@@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void)
 */
BUILD_BUG_ON(vaddr_start >= vaddr_end);
BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) &&
-vaddr_end >= EFI_VA_START);
+vaddr_end >= EFI_VA_END);
BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) ||
  IS_ENABLED(CONFIG_EFI)) &&
 vaddr_end >= __START_KERNEL_map);
-- 
2.5.5