From: Feng Tang <feng.tang@intel.com>
To: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, "H . Peter Anvin" <hpa@zytor.com>,
Dave Hansen <dave.hansen@intel.com>,
x86@kernel.org, linux-kernel@vger.kernel.org,
nivedita@alum.mit.edu, thomas.lendacky@amd.com,
yazen.ghannam@amd.com, wei.huang2@amd.com
Subject: Re: [PATCH v4] tools/x86: Add a kcpuid tool to show raw CPU features
Date: Tue, 19 Jan 2021 20:56:39 +0800 [thread overview]
Message-ID: <20210119125639.GA7976@shbuild999.sh.intel.com> (raw)
In-Reply-To: <20210119091116.GA27433@zn.tnic>
On Tue, Jan 19, 2021 at 10:11:16AM +0100, Borislav Petkov wrote:
> On Tue, Jan 19, 2021 at 01:19:42PM +0800, Feng Tang wrote:
> > Sorry, after testing on more platforms, the following is needed to fix
> > a potential array overflow ((a full patch with fix is also attached)
> >
> > diff --git a/tools/arch/x86/kcpuid/kcpuid.c b/tools/arch/x86/kcpuid/kcpuid.c
> > index 3ea607b..bf68335 100644
> > --- a/tools/arch/x86/kcpuid/kcpuid.c
> > +++ b/tools/arch/x86/kcpuid/kcpuid.c
> > @@ -329,7 +329,8 @@ static int parse_line(char *line)
> > range = leafs_basic;
> >
> > index &= 0x7FFFFFFF;
> > - if ((int)index > range->nr)
> > + /* range->nr equals to max index plus 1 */
> > + if ((int)index >= range->nr)
>
> That comment is basically repeating the code. What it should do is
> explain *why* that test is being done or not be there at all.
Right! So this is better?
/* Skip line parsing for non-existing indexes */
Thanks,
Feng
> --
> Regards/Gruss,
> Boris.
>
> https://people.kernel.org/tglx/notes-about-netiquette
next prev parent reply other threads:[~2021-01-19 13:11 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-18 7:35 [PATCH v4] tools/x86: Add a kcpuid tool to show raw CPU features Feng Tang
2021-01-19 5:19 ` Feng Tang
2021-01-19 9:11 ` Borislav Petkov
2021-01-19 12:56 ` Feng Tang [this message]
2021-01-19 13:10 ` Borislav Petkov
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