diff mbox

ARM: mvebu: declare asm symbols as character arrays in pmsu.c

Message ID 20180620043109.1190-1-ethan@ethantuttle.com (mailing list archive)
State New, archived
Headers show

Commit Message

Ethan Tuttle June 20, 2018, 4:31 a.m. UTC
With CONFIG_FORTIFY_SOURCE, memcpy uses the declared size of operands to
detect buffer overflows.  If src or dest is declared as a char, attempts to
copy more than byte will result in a fortify_panic().

Address this problem in mvebu_setup_boot_addr_wa() by declaring
mvebu_boot_wa_start and mvebu_boot_wa_end as character arrays.  Also remove
a couple addressof operators to avoid "arithmetic on pointer to an
incomplete type" compiler error.

See commit 54a7d50b9205 ("x86: mark kprobe templates as character arrays,
not single characters") for a similar fix.

Fixes "detected buffer overflow in memcpy" error during init on some mvebu
systems (armada-370-xp, armada-375):

(fortify_panic) from (mvebu_setup_boot_addr_wa+0xb0/0xb4)
(mvebu_setup_boot_addr_wa) from (mvebu_v7_cpu_pm_init+0x154/0x204)
(mvebu_v7_cpu_pm_init) from (do_one_initcall+0x7c/0x1a8)
(do_one_initcall) from (kernel_init_freeable+0x1bc/0x254)
(kernel_init_freeable) from (kernel_init+0x8/0x114)
(kernel_init) from (ret_from_fork+0x14/0x2c)

Signed-off-by: Ethan Tuttle <ethan@ethantuttle.com>
Tested-by: Ethan Tuttle <ethan@ethantuttle.com>
---
 arch/arm/mach-mvebu/pmsu.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Gregory CLEMENT June 27, 2018, 6:20 a.m. UTC | #1
Hi Ethan,
 
 On mar., juin 19 2018, Ethan Tuttle <ethan@ethantuttle.com> wrote:

> With CONFIG_FORTIFY_SOURCE, memcpy uses the declared size of operands to
> detect buffer overflows.  If src or dest is declared as a char, attempts to
> copy more than byte will result in a fortify_panic().
>
> Address this problem in mvebu_setup_boot_addr_wa() by declaring
> mvebu_boot_wa_start and mvebu_boot_wa_end as character arrays.  Also remove
> a couple addressof operators to avoid "arithmetic on pointer to an
> incomplete type" compiler error.
>
> See commit 54a7d50b9205 ("x86: mark kprobe templates as character arrays,
> not single characters") for a similar fix.
>
> Fixes "detected buffer overflow in memcpy" error during init on some mvebu
> systems (armada-370-xp, armada-375):
>
> (fortify_panic) from (mvebu_setup_boot_addr_wa+0xb0/0xb4)
> (mvebu_setup_boot_addr_wa) from (mvebu_v7_cpu_pm_init+0x154/0x204)
> (mvebu_v7_cpu_pm_init) from (do_one_initcall+0x7c/0x1a8)
> (do_one_initcall) from (kernel_init_freeable+0x1bc/0x254)
> (kernel_init_freeable) from (kernel_init+0x8/0x114)
> (kernel_init) from (ret_from_fork+0x14/0x2c)
>
> Signed-off-by: Ethan Tuttle <ethan@ethantuttle.com>
> Tested-by: Ethan Tuttle <ethan@ethantuttle.com>

Out of curiosity on which platform did you test it?

Applied on mvebu/arm

Thanks,

Gregory



> ---
>  arch/arm/mach-mvebu/pmsu.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
> index 27a78c80e5b1..73d5d72dfc3e 100644
> --- a/arch/arm/mach-mvebu/pmsu.c
> +++ b/arch/arm/mach-mvebu/pmsu.c
> @@ -116,8 +116,8 @@ void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
>  		PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
>  }
>  
> -extern unsigned char mvebu_boot_wa_start;
> -extern unsigned char mvebu_boot_wa_end;
> +extern unsigned char mvebu_boot_wa_start[];
> +extern unsigned char mvebu_boot_wa_end[];
>  
>  /*
>   * This function sets up the boot address workaround needed for SMP
> @@ -130,7 +130,7 @@ int mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,
>  			     phys_addr_t resume_addr_reg)
>  {
>  	void __iomem *sram_virt_base;
> -	u32 code_len = &mvebu_boot_wa_end - &mvebu_boot_wa_start;
> +	u32 code_len = mvebu_boot_wa_end - mvebu_boot_wa_start;
>  
>  	mvebu_mbus_del_window(BOOTROM_BASE, BOOTROM_SIZE);
>  	mvebu_mbus_add_window_by_id(crypto_eng_target, crypto_eng_attribute,
> -- 
> 2.17.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
Ethan Tuttle June 27, 2018, 2:39 p.m. UTC | #2
Hi Gregory.

On Tue, Jun 26, 2018 at 11:20 PM, Gregory CLEMENT
<gregory.clement@bootlin.com> wrote:
> Hi Ethan,
>
>  On mar., juin 19 2018, Ethan Tuttle <ethan@ethantuttle.com> wrote:
>
>> With CONFIG_FORTIFY_SOURCE, memcpy uses the declared size of operands to
>> detect buffer overflows.  If src or dest is declared as a char, attempts to
>> copy more than byte will result in a fortify_panic().
>>
>> Address this problem in mvebu_setup_boot_addr_wa() by declaring
>> mvebu_boot_wa_start and mvebu_boot_wa_end as character arrays.  Also remove
>> a couple addressof operators to avoid "arithmetic on pointer to an
>> incomplete type" compiler error.
>>
>> See commit 54a7d50b9205 ("x86: mark kprobe templates as character arrays,
>> not single characters") for a similar fix.
>>
>> Fixes "detected buffer overflow in memcpy" error during init on some mvebu
>> systems (armada-370-xp, armada-375):
>>
>> (fortify_panic) from (mvebu_setup_boot_addr_wa+0xb0/0xb4)
>> (mvebu_setup_boot_addr_wa) from (mvebu_v7_cpu_pm_init+0x154/0x204)
>> (mvebu_v7_cpu_pm_init) from (do_one_initcall+0x7c/0x1a8)
>> (do_one_initcall) from (kernel_init_freeable+0x1bc/0x254)
>> (kernel_init_freeable) from (kernel_init+0x8/0x114)
>> (kernel_init) from (ret_from_fork+0x14/0x2c)
>>
>> Signed-off-by: Ethan Tuttle <ethan@ethantuttle.com>
>> Tested-by: Ethan Tuttle <ethan@ethantuttle.com>
>
> Out of curiosity on which platform did you test it?

I found the problem on my Mirabox after a kernel upgrade, and verified the fix
on the Mirabox as well.

I just observed in the code that the panic should also happen on armada-375,
didn't do any testing there.

BTW, just realizing I did not test with CONFIG_FORTIFY_SOURCE off.  But
I imagine it will work.  Let me know if you think that requires testing.

> Applied on mvebu/arm

Excellent!  Thank you.

Ethan

>
> Thanks,
>
> Gregory
>
>
>
>> ---
>>  arch/arm/mach-mvebu/pmsu.c | 6 +++---
>>  1 file changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
>> index 27a78c80e5b1..73d5d72dfc3e 100644
>> --- a/arch/arm/mach-mvebu/pmsu.c
>> +++ b/arch/arm/mach-mvebu/pmsu.c
>> @@ -116,8 +116,8 @@ void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
>>               PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
>>  }
>>
>> -extern unsigned char mvebu_boot_wa_start;
>> -extern unsigned char mvebu_boot_wa_end;
>> +extern unsigned char mvebu_boot_wa_start[];
>> +extern unsigned char mvebu_boot_wa_end[];
>>
>>  /*
>>   * This function sets up the boot address workaround needed for SMP
>> @@ -130,7 +130,7 @@ int mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,
>>                            phys_addr_t resume_addr_reg)
>>  {
>>       void __iomem *sram_virt_base;
>> -     u32 code_len = &mvebu_boot_wa_end - &mvebu_boot_wa_start;
>> +     u32 code_len = mvebu_boot_wa_end - mvebu_boot_wa_start;
>>
>>       mvebu_mbus_del_window(BOOTROM_BASE, BOOTROM_SIZE);
>>       mvebu_mbus_add_window_by_id(crypto_eng_target, crypto_eng_attribute,
>> --
>> 2.17.1
>>
>>
>> _______________________________________________
>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
> --
> Gregory Clement, Bootlin (formerly Free Electrons)
> Embedded Linux and Kernel engineering
> http://bootlin.com
Gregory CLEMENT June 28, 2018, 1:07 p.m. UTC | #3
Hi Ethan,
 
 On mer., juin 27 2018, Ethan Tuttle <ethan@ethantuttle.com> wrote:

> Hi Gregory.
>
> On Tue, Jun 26, 2018 at 11:20 PM, Gregory CLEMENT
> <gregory.clement@bootlin.com> wrote:
>> Hi Ethan,
>>
>>  On mar., juin 19 2018, Ethan Tuttle <ethan@ethantuttle.com> wrote:
>>
>>> With CONFIG_FORTIFY_SOURCE, memcpy uses the declared size of operands to
>>> detect buffer overflows.  If src or dest is declared as a char, attempts to
>>> copy more than byte will result in a fortify_panic().
>>>
>>> Address this problem in mvebu_setup_boot_addr_wa() by declaring
>>> mvebu_boot_wa_start and mvebu_boot_wa_end as character arrays.  Also remove
>>> a couple addressof operators to avoid "arithmetic on pointer to an
>>> incomplete type" compiler error.
>>>
>>> See commit 54a7d50b9205 ("x86: mark kprobe templates as character arrays,
>>> not single characters") for a similar fix.
>>>
>>> Fixes "detected buffer overflow in memcpy" error during init on some mvebu
>>> systems (armada-370-xp, armada-375):
>>>
>>> (fortify_panic) from (mvebu_setup_boot_addr_wa+0xb0/0xb4)
>>> (mvebu_setup_boot_addr_wa) from (mvebu_v7_cpu_pm_init+0x154/0x204)
>>> (mvebu_v7_cpu_pm_init) from (do_one_initcall+0x7c/0x1a8)
>>> (do_one_initcall) from (kernel_init_freeable+0x1bc/0x254)
>>> (kernel_init_freeable) from (kernel_init+0x8/0x114)
>>> (kernel_init) from (ret_from_fork+0x14/0x2c)
>>>
>>> Signed-off-by: Ethan Tuttle <ethan@ethantuttle.com>
>>> Tested-by: Ethan Tuttle <ethan@ethantuttle.com>
>>
>> Out of curiosity on which platform did you test it?
>
> I found the problem on my Mirabox after a kernel upgrade, and verified the fix
> on the Mirabox as well.
>
> I just observed in the code that the panic should also happen on armada-375,
> didn't do any testing there.
>
> BTW, just realizing I did not test with CONFIG_FORTIFY_SOURCE off.  But
> I imagine it will work.  Let me know if you think that requires
> testing.

No it's OK, thanks for extra information.

Gregory

>
>> Applied on mvebu/arm
>
> Excellent!  Thank you.
>
> Ethan
>
>>
>> Thanks,
>>
>> Gregory
>>
>>
>>
>>> ---
>>>  arch/arm/mach-mvebu/pmsu.c | 6 +++---
>>>  1 file changed, 3 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
>>> index 27a78c80e5b1..73d5d72dfc3e 100644
>>> --- a/arch/arm/mach-mvebu/pmsu.c
>>> +++ b/arch/arm/mach-mvebu/pmsu.c
>>> @@ -116,8 +116,8 @@ void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
>>>               PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
>>>  }
>>>
>>> -extern unsigned char mvebu_boot_wa_start;
>>> -extern unsigned char mvebu_boot_wa_end;
>>> +extern unsigned char mvebu_boot_wa_start[];
>>> +extern unsigned char mvebu_boot_wa_end[];
>>>
>>>  /*
>>>   * This function sets up the boot address workaround needed for SMP
>>> @@ -130,7 +130,7 @@ int mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,
>>>                            phys_addr_t resume_addr_reg)
>>>  {
>>>       void __iomem *sram_virt_base;
>>> -     u32 code_len = &mvebu_boot_wa_end - &mvebu_boot_wa_start;
>>> +     u32 code_len = mvebu_boot_wa_end - mvebu_boot_wa_start;
>>>
>>>       mvebu_mbus_del_window(BOOTROM_BASE, BOOTROM_SIZE);
>>>       mvebu_mbus_add_window_by_id(crypto_eng_target, crypto_eng_attribute,
>>> --
>>> 2.17.1
>>>
>>>
>>> _______________________________________________
>>> linux-arm-kernel mailing list
>>> linux-arm-kernel@lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
>> --
>> Gregory Clement, Bootlin (formerly Free Electrons)
>> Embedded Linux and Kernel engineering
>> http://bootlin.com
diff mbox

Patch

diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
index 27a78c80e5b1..73d5d72dfc3e 100644
--- a/arch/arm/mach-mvebu/pmsu.c
+++ b/arch/arm/mach-mvebu/pmsu.c
@@ -116,8 +116,8 @@  void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
 		PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
 }
 
-extern unsigned char mvebu_boot_wa_start;
-extern unsigned char mvebu_boot_wa_end;
+extern unsigned char mvebu_boot_wa_start[];
+extern unsigned char mvebu_boot_wa_end[];
 
 /*
  * This function sets up the boot address workaround needed for SMP
@@ -130,7 +130,7 @@  int mvebu_setup_boot_addr_wa(unsigned int crypto_eng_target,
 			     phys_addr_t resume_addr_reg)
 {
 	void __iomem *sram_virt_base;
-	u32 code_len = &mvebu_boot_wa_end - &mvebu_boot_wa_start;
+	u32 code_len = mvebu_boot_wa_end - mvebu_boot_wa_start;
 
 	mvebu_mbus_del_window(BOOTROM_BASE, BOOTROM_SIZE);
 	mvebu_mbus_add_window_by_id(crypto_eng_target, crypto_eng_attribute,