Re: [PATCH 1/3] x86/MCE/AMD: Redo function to get SMCA bank type

2018-02-14 Thread Borislav Petkov 
On Wed, Feb 14, 2018 at 04:38:34PM +, Ghannam, Yazen wrote:
> I know that we're declaring smca_banks[] to have MAX_NR_BANKS items. But
> shouldn't we directly check that an index is within the bounds of the array?
> We'll have a bug if we check against MAX_NR_BANKS and the definition of
> smca_banks[] changes.

Then we don't need MAX_NR_BANKS. We either keep them in sync or kill it.

-- 
Regards/Gruss,
Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 
(AG Nürnberg)
--

RE: [PATCH 1/3] x86/MCE/AMD: Redo function to get SMCA bank type

2018-02-14 Thread Ghannam, Yazen 
> -Original Message-
> From: Borislav Petkov [mailto:b...@alien8.de]
> Sent: Thursday, February 8, 2018 10:05 AM
> To: Ghannam, Yazen 
> Cc: linux-e...@vger.kernel.org; linux-kernel@vger.kernel.org; b...@suse.de;
> tony.l...@intel.com; x...@kernel.org
> Subject: Re: [PATCH 1/3] x86/MCE/AMD: Redo function to get SMCA bank type
> 
> On Thu, Feb 01, 2018 at 12:48:11PM -0600, Yazen Ghannam wrote:
> >  arch/x86/kernel/cpu/mcheck/mce_amd.c | 15 +++
> >  1 file changed, 7 insertions(+), 8 deletions(-)
> >
> > diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c
> b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> > index 0f32ad242324..4e16afc0794d 100644
> > --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
> > +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> > @@ -110,14 +110,14 @@ const char *smca_get_long_name(enum
> smca_bank_types t)
> >  }
> >  EXPORT_SYMBOL_GPL(smca_get_long_name);
> >
> > -static enum smca_bank_types smca_get_bank_type(struct mce *m)
> > +static enum smca_bank_types smca_get_bank_type(unsigned int bank)
> >  {
> > struct smca_bank *b;
> >
> > -   if (m->bank >= N_SMCA_BANK_TYPES)
> > +   if (bank >= ARRAY_SIZE(smca_banks))
> 
> MAX_NR_BANKS
> 

I know that we're declaring smca_banks[] to have MAX_NR_BANKS items. But
shouldn't we directly check that an index is within the bounds of the array?
We'll have a bug if we check against MAX_NR_BANKS and the definition of
smca_banks[] changes.

Thanks,
Yazen

Re: [PATCH 1/3] x86/MCE/AMD: Redo function to get SMCA bank type

2018-02-08 Thread Borislav Petkov 
On Thu, Feb 01, 2018 at 12:48:11PM -0600, Yazen Ghannam wrote:
>  arch/x86/kernel/cpu/mcheck/mce_amd.c | 15 +++
>  1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c 
> b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> index 0f32ad242324..4e16afc0794d 100644
> --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
> +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
> @@ -110,14 +110,14 @@ const char *smca_get_long_name(enum smca_bank_types t)
>  }
>  EXPORT_SYMBOL_GPL(smca_get_long_name);
>  
> -static enum smca_bank_types smca_get_bank_type(struct mce *m)
> +static enum smca_bank_types smca_get_bank_type(unsigned int bank)
>  {
>   struct smca_bank *b;
>  
> - if (m->bank >= N_SMCA_BANK_TYPES)
> + if (bank >= ARRAY_SIZE(smca_banks))

MAX_NR_BANKS

-- 
Regards/Gruss,
Boris.

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